id,page,ref,title,content,breadcrumbs,references changelog:id33,changelog,id33,0.55 (2021-02-18),"Support for cross-database SQL queries and built-in support for serving via HTTPS. The new --crossdb command-line option causes Datasette to attach up to ten database files to the same /_memory database connection. This enables cross-database SQL queries, including the ability to use joins and unions to combine data from tables that exist in different database files. See Cross-database queries for details. ( #283 ) --ssl-keyfile and --ssl-certfile options can be used to specify a TLS certificate, allowing Datasette to serve traffic over https:// without needing to run it behind a separate proxy. ( #1221 ) The /:memory: page has been renamed (and redirected) to /_memory for consistency with the new /_internal database introduced in Datasette 0.54. ( #1205 ) Added plugin testing documentation on Using pdb for errors thrown inside Datasette . ( #1207 ) The official Datasette Docker image now uses Python 3.7.10, applying the latest security fix for that Python version. ( #1235 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/283"", ""label"": ""#283""}, {""href"": ""https://github.com/simonw/datasette/issues/1221"", ""label"": ""#1221""}, {""href"": ""https://github.com/simonw/datasette/issues/1205"", ""label"": ""#1205""}, {""href"": ""https://github.com/simonw/datasette/issues/1207"", ""label"": ""#1207""}, {""href"": ""https://hub.docker.com/r/datasetteproject/datasette"", ""label"": ""official Datasette Docker image""}, {""href"": ""https://www.python.org/downloads/release/python-3710/"", ""label"": ""the latest security fix""}, {""href"": ""https://github.com/simonw/datasette/issues/1235"", ""label"": ""#1235""}]" changelog:id34,changelog,id34,0.54.1 (2021-02-02),Fixed a bug where ?_search= and ?_sort= parameters were incorrectly duplicated when the filter form on the table page was re-submitted. ( #1214 ),"[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/1214"", ""label"": ""#1214""}]" changelog:id35,changelog,id35,0.54 (2021-01-25),"The two big new features in this release are the _internal SQLite in-memory database storing details of all connected databases and tables, and support for JavaScript modules in plugins and additional scripts. For additional commentary on this release, see Datasette 0.54, the annotated release notes .","[""Changelog""]","[{""href"": ""https://simonwillison.net/2021/Jan/25/datasette/"", ""label"": ""Datasette 0.54, the annotated release notes""}]" changelog:id36,changelog,id36,Other changes,"Datasette can now open multiple database files with the same name, e.g. if you run datasette path/to/one.db path/to/other/one.db . ( #509 ) datasette publish cloudrun now sets force_https_urls for every deployment, fixing some incorrect http:// links. ( #1178 ) Fixed a bug in the example nginx configuration in Running Datasette behind a proxy . ( #1091 ) The Datasette Ecosystem documentation page has been reduced in size in favour of the datasette.io tools and plugins directories. ( #1182 ) The request object now provides a request.full_path property, which returns the path including any query string. ( #1184 ) Better error message for disallowed PRAGMA clauses in SQL queries. ( #1185 ) datasette publish heroku now deploys using python-3.8.7 . New plugin testing documentation on Testing outbound HTTP calls with pytest-httpx . ( #1198 ) All ?_* query string parameters passed to the table page are now persisted in hidden form fields, so parameters such as ?_size=10 will be correctly passed to the next page when query filters are changed. ( #1194 ) Fixed a bug loading a database file called test-database (1).sqlite . ( #1181 )","[""Changelog"", ""0.54 (2021-01-25)""]","[{""href"": ""https://github.com/simonw/datasette/issues/509"", ""label"": ""#509""}, {""href"": ""https://github.com/simonw/datasette/issues/1178"", ""label"": ""#1178""}, {""href"": ""https://github.com/simonw/datasette/issues/1091"", ""label"": ""#1091""}, {""href"": ""https://datasette.io/tools"", ""label"": ""tools""}, {""href"": ""https://datasette.io/plugins"", ""label"": ""plugins""}, {""href"": ""https://github.com/simonw/datasette/issues/1182"", ""label"": ""#1182""}, {""href"": ""https://github.com/simonw/datasette/issues/1184"", ""label"": ""#1184""}, {""href"": ""https://github.com/simonw/datasette/issues/1185"", ""label"": ""#1185""}, {""href"": ""https://github.com/simonw/datasette/issues/1198"", ""label"": ""#1198""}, {""href"": ""https://github.com/simonw/datasette/issues/1194"", ""label"": ""#1194""}, {""href"": ""https://github.com/simonw/datasette/issues/1181"", ""label"": ""#1181""}]" changelog:id37,changelog,id37,0.53 (2020-12-10),"Datasette has an official project website now, at https://datasette.io/ . This release mainly updates the documentation to reflect the new site. New ?column__arraynotcontains= table filter. ( #1132 ) datasette serve has a new --create option, which will create blank database files if they do not already exist rather than exiting with an error. ( #1135 ) New ?_header=off option for CSV export which omits the CSV header row, documented here . ( #1133 ) ""Powered by Datasette"" link in the footer now links to https://datasette.io/ . ( #1138 ) Project news no longer lives in the README - it can now be found at https://datasette.io/news . ( #1137 )","[""Changelog""]","[{""href"": ""https://datasette.io/"", ""label"": ""https://datasette.io/""}, {""href"": ""https://github.com/simonw/datasette/issues/1132"", ""label"": ""#1132""}, {""href"": ""https://github.com/simonw/datasette/issues/1135"", ""label"": ""#1135""}, {""href"": ""https://github.com/simonw/datasette/issues/1133"", ""label"": ""#1133""}, {""href"": ""https://datasette.io/"", ""label"": ""https://datasette.io/""}, {""href"": ""https://github.com/simonw/datasette/issues/1138"", ""label"": ""#1138""}, {""href"": ""https://datasette.io/news"", ""label"": ""https://datasette.io/news""}, {""href"": ""https://github.com/simonw/datasette/issues/1137"", ""label"": ""#1137""}]" changelog:id38,changelog,id38,0.52.5 (2020-12-09),Fix for error caused by combining the _searchmode=raw and ?_search_COLUMN parameters. ( #1134 ),"[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/1134"", ""label"": ""#1134""}]" changelog:id39,changelog,id39,0.52.4 (2020-12-05),"Show pysqlite3 version on /-/versions , if installed. ( #1125 ) Errors output by Datasette (e.g. for invalid SQL queries) now go to stderr , not stdout . ( #1131 ) Fix for a startup error on windows caused by unnecessary from os import EX_CANTCREAT - thanks, Abdussamet Koçak. ( #1094 )","[""Changelog""]","[{""href"": ""https://github.com/coleifer/pysqlite3"", ""label"": ""pysqlite3""}, {""href"": ""https://github.com/simonw/datasette/issues/1125"", ""label"": ""#1125""}, {""href"": ""https://github.com/simonw/datasette/issues/1131"", ""label"": ""#1131""}, {""href"": ""https://github.com/simonw/datasette/issues/1094"", ""label"": ""#1094""}]" changelog:id4,changelog,id4,0.64.4 (2023-09-21),Fix for a crashing bug caused by viewing the table page for a named in-memory database. ( #2189 ),"[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/2189"", ""label"": ""#2189""}]" changelog:id40,changelog,id40,0.52.3 (2020-12-03),Fixed bug where static assets would 404 for Datasette installed on ARM Amazon Linux. ( #1124 ),"[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/1124"", ""label"": ""#1124""}]" changelog:id41,changelog,id41,0.52.2 (2020-12-02),"Generated columns from SQLite 3.31.0 or higher are now correctly displayed. ( #1116 ) Error message if you attempt to open a SpatiaLite database now suggests using --load-extension=spatialite if it detects that the extension is available in a common location. ( #1115 ) OPTIONS requests against the /database page no longer raise a 500 error. ( #1100 ) Databases larger than 32MB that are published to Cloud Run can now be downloaded. ( #749 ) Fix for misaligned cog icon on table and database pages. Thanks, Abdussamet Koçak. ( #1121 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/1116"", ""label"": ""#1116""}, {""href"": ""https://github.com/simonw/datasette/issues/1115"", ""label"": ""#1115""}, {""href"": ""https://github.com/simonw/datasette/issues/1100"", ""label"": ""#1100""}, {""href"": ""https://github.com/simonw/datasette/issues/749"", ""label"": ""#749""}, {""href"": ""https://github.com/simonw/datasette/issues/1121"", ""label"": ""#1121""}]" changelog:id42,changelog,id42,0.52.1 (2020-11-29),"Documentation on Testing plugins now recommends using datasette.client . ( #1102 ) Fix bug where compound foreign keys produced broken links. ( #1098 ) datasette --load-module=spatialite now also checks for /usr/local/lib/mod_spatialite.so . Thanks, Dan Peterson. ( #1114 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/1102"", ""label"": ""#1102""}, {""href"": ""https://github.com/simonw/datasette/issues/1098"", ""label"": ""#1098""}, {""href"": ""https://github.com/simonw/datasette/issues/1114"", ""label"": ""#1114""}]" changelog:id43,changelog,id43,0.52 (2020-11-28),"This release includes a number of changes relating to an internal rebranding effort: Datasette's configuration mechanism (things like datasette --config default_page_size:10 ) has been renamed to settings . New --setting default_page_size 10 option as a replacement for --config default_page_size:10 (note the lack of a colon). The --config option is deprecated but will continue working until Datasette 1.0. ( #992 ) The /-/config introspection page is now /-/settings , and the previous page redirects to the new one. ( #1103 ) The config.json file in Configuration directory mode is now called settings.json . ( #1104 ) The undocumented datasette.config() internal method has been replaced by a documented .setting(key) method. ( #1107 ) Also in this release: New plugin hook: database_actions(datasette, actor, database, request) , which adds menu items to a new cog menu shown at the top of the database page. ( #1077 ) datasette publish cloudrun has a new --apt-get-install option that can be used to install additional Ubuntu packages as part of the deployment. This is useful for deploying the new datasette-ripgrep plugin . ( #1110 ) Swept the documentation to remove words that minimize involved difficulty. ( #1089 ) And some bug fixes: Foreign keys linking to rows with blank label columns now display as a hyphen, allowing those links to be clicked. ( #1086 ) Fixed bug where row pages could sometimes 500 if the underlying queries exceeded a time limit. ( #1088 ) Fixed a bug where the table action menu could appear partially obscured by the edge of the page. ( #1084 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/992"", ""label"": ""#992""}, {""href"": ""https://github.com/simonw/datasette/issues/1103"", ""label"": ""#1103""}, {""href"": ""https://github.com/simonw/datasette/issues/1104"", ""label"": ""#1104""}, {""href"": ""https://github.com/simonw/datasette/issues/1107"", ""label"": ""#1107""}, {""href"": ""https://github.com/simonw/datasette/issues/1077"", ""label"": ""#1077""}, {""href"": ""https://github.com/simonw/datasette-ripgrep"", ""label"": ""datasette-ripgrep plugin""}, {""href"": ""https://github.com/simonw/datasette/issues/1110"", ""label"": ""#1110""}, {""href"": ""https://github.com/simonw/datasette/issues/1089"", ""label"": ""#1089""}, {""href"": ""https://github.com/simonw/datasette/issues/1086"", ""label"": ""#1086""}, {""href"": ""https://github.com/simonw/datasette/issues/1088"", ""label"": ""#1088""}, {""href"": ""https://github.com/simonw/datasette/issues/1084"", ""label"": ""#1084""}]" changelog:id44,changelog,id44,0.51.1 (2020-10-31),Improvements to the new Binary data documentation page.,"[""Changelog""]",[] changelog:id45,changelog,id45,0.51 (2020-10-31),"A new visual design, plugin hooks for adding navigation options, better handling of binary data, URL building utility methods and better support for running Datasette behind a proxy.","[""Changelog""]",[] changelog:id46,changelog,id46,Smaller changes,"Wide tables shown within Datasette now scroll horizontally ( #998 ). This is achieved using a new
element which may impact the implementation of some plugins (for example this change to datasette-cluster-map ). New debug-menu permission. ( #1068 ) Removed --debug option, which didn't do anything. ( #814 ) Link: HTTP header pagination. ( #1014 ) x button for clearing filters. ( #1016 ) Edit SQL button on canned queries, ( #1019 ) --load-extension=spatialite shortcut. ( #1028 ) scale-in animation for column action menu. ( #1039 ) Option to pass a list of templates to .render_template() is now documented. ( #1045 ) New datasette.urls.static_plugins() method. ( #1033 ) datasette -o option now opens the most relevant page. ( #976 ) datasette --cors option now enables access to /database.db downloads. ( #1057 ) Database file downloads now implement cascading permissions, so you can download a database if you have view-database-download permission even if you do not have permission to access the Datasette instance. ( #1058 ) New documentation on Designing URLs for your plugin . ( #1053 )","[""Changelog"", ""0.51 (2020-10-31)""]","[{""href"": ""https://github.com/simonw/datasette/issues/998"", ""label"": ""#998""}, {""href"": ""https://github.com/simonw/datasette-cluster-map/commit/fcb4abbe7df9071c5ab57defd39147de7145b34e"", ""label"": ""this change to datasette-cluster-map""}, {""href"": ""https://github.com/simonw/datasette/issues/1068"", ""label"": ""#1068""}, {""href"": ""https://github.com/simonw/datasette/issues/814"", ""label"": ""#814""}, {""href"": ""https://github.com/simonw/datasette/issues/1014"", ""label"": ""#1014""}, {""href"": ""https://github.com/simonw/datasette/issues/1016"", ""label"": ""#1016""}, {""href"": ""https://github.com/simonw/datasette/issues/1019"", ""label"": ""#1019""}, {""href"": ""https://github.com/simonw/datasette/issues/1028"", ""label"": ""#1028""}, {""href"": ""https://github.com/simonw/datasette/issues/1039"", ""label"": ""#1039""}, {""href"": ""https://github.com/simonw/datasette/issues/1045"", ""label"": ""#1045""}, {""href"": ""https://github.com/simonw/datasette/issues/1033"", ""label"": ""#1033""}, {""href"": ""https://github.com/simonw/datasette/issues/976"", ""label"": ""#976""}, {""href"": ""https://github.com/simonw/datasette/issues/1057"", ""label"": ""#1057""}, {""href"": ""https://github.com/simonw/datasette/issues/1058"", ""label"": ""#1058""}, {""href"": ""https://github.com/simonw/datasette/issues/1053"", ""label"": ""#1053""}]" changelog:id47,changelog,id47,0.50.2 (2020-10-09),Fixed another bug introduced in 0.50 where column header links on the table page were broken. ( #1011 ),"[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/1011"", ""label"": ""#1011""}]" changelog:id48,changelog,id48,0.50.1 (2020-10-09),"Fixed a bug introduced in 0.50 where the export as JSON/CSV links on the table, row and query pages were broken. ( #1010 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/1010"", ""label"": ""#1010""}]" changelog:id49,changelog,id49,0.50 (2020-10-09),"The key new feature in this release is the column actions menu on the table page ( #891 ). This can be used to sort a column in ascending or descending order, facet data by that column or filter the table to just rows that have a value for that column. Plugin authors can use the new datasette.client object to make internal HTTP requests from their plugins, allowing them to make use of Datasette's JSON API. ( #943 ) New Deploying Datasette documentation with guides for deploying Datasette on a Linux server using systemd or to hosting providers that support buildpacks . ( #514 , #997 ) Other improvements in this release: Publishing to Google Cloud Run documentation now covers Google Cloud SDK options. Thanks, Geoffrey Hing. ( #995 ) New datasette -o option which opens your browser as soon as Datasette starts up. ( #970 ) Datasette now sets sqlite3.enable_callback_tracebacks(True) so that errors in custom SQL functions will display tracebacks. ( #891 ) Fixed two rendering bugs with column headers in portrait mobile view. ( #978 , #980 ) New db.table_column_details(table) introspection method for retrieving full details of the columns in a specific table, see Database introspection . Fixed a routing bug with custom page wildcard templates. ( #996 ) datasette publish heroku now deploys using Python 3.8.6. New datasette publish heroku --tar= option. ( #969 ) OPTIONS requests against HTML pages no longer return a 500 error. ( #1001 ) Datasette now supports Python 3.9. See also Datasette 0.50: The annotated release notes .","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/891"", ""label"": ""#891""}, {""href"": ""https://github.com/simonw/datasette/issues/943"", ""label"": ""#943""}, {""href"": ""https://github.com/simonw/datasette/issues/514"", ""label"": ""#514""}, {""href"": ""https://github.com/simonw/datasette/issues/997"", ""label"": ""#997""}, {""href"": ""https://github.com/simonw/datasette/pull/995"", ""label"": ""#995""}, {""href"": ""https://github.com/simonw/datasette/issues/970"", ""label"": ""#970""}, {""href"": ""https://github.com/simonw/datasette/issues/891"", ""label"": ""#891""}, {""href"": ""https://github.com/simonw/datasette/issues/978"", ""label"": ""#978""}, {""href"": ""https://github.com/simonw/datasette/issues/980"", ""label"": ""#980""}, {""href"": ""https://github.com/simonw/datasette/issues/996"", ""label"": ""#996""}, {""href"": ""https://github.com/simonw/datasette/issues/969"", ""label"": ""#969""}, {""href"": ""https://github.com/simonw/datasette/issues/1001"", ""label"": ""#1001""}, {""href"": ""https://simonwillison.net/2020/Oct/9/datasette-0-50/"", ""label"": ""Datasette 0.50: The annotated release notes""}]" changelog:id5,changelog,id5,0.64.2 (2023-03-08),"Fixed a bug with datasette publish cloudrun where deploys all used the same Docker image tag. This was mostly inconsequential as the service is deployed as soon as the image has been pushed to the registry, but could result in the incorrect image being deployed if two different deploys for two separate services ran at exactly the same time. ( #2036 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/2036"", ""label"": ""#2036""}]" changelog:id50,changelog,id50,0.49.1 (2020-09-15),Fixed a bug with writable canned queries that use magic parameters but accept no non-magic arguments. ( #967 ),"[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/967"", ""label"": ""#967""}]" changelog:id51,changelog,id51,0.49 (2020-09-14),"See also Datasette 0.49: The annotated release notes . Writable canned queries now expose a JSON API, see JSON API for writable canned queries . ( #880 ) New mechanism for defining page templates with custom path parameters - a template file called pages/about/{slug}.html will be used to render any requests to /about/something . See Path parameters for pages . ( #944 ) register_output_renderer() render functions can now return a Response . ( #953 ) New --upgrade option for datasette install . ( #945 ) New datasette --pdb option. ( #962 ) datasette --get exit code now reflects the internal HTTP status code. ( #947 ) New raise_404() template function for returning 404 errors. ( #964 ) datasette publish heroku now deploys using Python 3.8.5 Upgraded CodeMirror to 5.57.0. ( #948 ) Upgraded code style to Black 20.8b1. ( #958 ) Fixed bug where selected facets were not correctly persisted in hidden form fields on the table page. ( #963 ) Renamed the default error template from 500.html to error.html . Custom error pages are now documented, see Custom error pages . ( #965 )","[""Changelog""]","[{""href"": ""https://simonwillison.net/2020/Sep/15/datasette-0-49/"", ""label"": ""Datasette 0.49: The annotated release notes""}, {""href"": ""https://github.com/simonw/datasette/issues/880"", ""label"": ""#880""}, {""href"": ""https://github.com/simonw/datasette/issues/944"", ""label"": ""#944""}, {""href"": ""https://github.com/simonw/datasette/issues/953"", ""label"": ""#953""}, {""href"": ""https://github.com/simonw/datasette/issues/945"", ""label"": ""#945""}, {""href"": ""https://github.com/simonw/datasette/issues/962"", ""label"": ""#962""}, {""href"": ""https://github.com/simonw/datasette/issues/947"", ""label"": ""#947""}, {""href"": ""https://github.com/simonw/datasette/issues/964"", ""label"": ""#964""}, {""href"": ""https://codemirror.net/"", ""label"": ""CodeMirror""}, {""href"": ""https://github.com/simonw/datasette/issues/948"", ""label"": ""#948""}, {""href"": ""https://github.com/simonw/datasette/issues/958"", ""label"": ""#958""}, {""href"": ""https://github.com/simonw/datasette/issues/963"", ""label"": ""#963""}, {""href"": ""https://github.com/simonw/datasette/issues/965"", ""label"": ""#965""}]" changelog:id52,changelog,id52,0.48 (2020-08-16),"Datasette documentation now lives at docs.datasette.io . db.is_mutable property is now documented and tested, see Database introspection . The extra_template_vars , extra_css_urls , extra_js_urls and extra_body_script plugin hooks now all accept the same arguments. See extra_template_vars(template, database, table, columns, view_name, request, datasette) for details. ( #939 ) Those hooks now accept a new columns argument detailing the table columns that will be rendered on that page. ( #938 ) Fixed bug where plugins calling db.execute_write_fn() could hang Datasette if the connection failed. ( #935 ) Fixed bug with the ?_nl=on output option and binary data. ( #914 )","[""Changelog""]","[{""href"": ""https://docs.datasette.io/"", ""label"": ""docs.datasette.io""}, {""href"": ""https://github.com/simonw/datasette/issues/939"", ""label"": ""#939""}, {""href"": ""https://github.com/simonw/datasette/issues/938"", ""label"": ""#938""}, {""href"": ""https://github.com/simonw/datasette/issues/935"", ""label"": ""#935""}, {""href"": ""https://github.com/simonw/datasette/issues/914"", ""label"": ""#914""}]" changelog:id53,changelog,id53,0.47.3 (2020-08-15),The datasette --get command-line mechanism now ensures any plugins using the startup() hook are correctly executed. ( #934 ),"[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/934"", ""label"": ""#934""}]" changelog:id54,changelog,id54,0.47.2 (2020-08-12),Fixed an issue with the Docker image published to Docker Hub . ( #931 ),"[""Changelog""]","[{""href"": ""https://hub.docker.com/r/datasetteproject/datasette"", ""label"": ""published to Docker Hub""}, {""href"": ""https://github.com/simonw/datasette/issues/931"", ""label"": ""#931""}]" changelog:id55,changelog,id55,0.47.1 (2020-08-11),Fixed a bug where the sdist distribution of Datasette was not correctly including the template files. ( #930 ),"[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/930"", ""label"": ""#930""}]" changelog:id56,changelog,id56,0.47 (2020-08-11),"Datasette now has a GitHub discussions forum for conversations about the project that go beyond just bug reports and issues. Datasette can now be installed on macOS using Homebrew! Run brew install simonw/datasette/datasette . See Using Homebrew . ( #335 ) Two new commands: datasette install name-of-plugin and datasette uninstall name-of-plugin . These are equivalent to pip install and pip uninstall but automatically run in the same virtual environment as Datasette, so users don't have to figure out where that virtual environment is - useful for installations created using Homebrew or pipx . See Installing plugins . ( #925 ) A new command-line option, datasette --get , accepts a path to a URL within the Datasette instance. It will run that request through Datasette (without starting a web server) and print out the response. See datasette --get for an example. ( #926 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/discussions"", ""label"": ""a GitHub discussions forum""}, {""href"": ""https://github.com/simonw/datasette/issues/335"", ""label"": ""#335""}, {""href"": ""https://github.com/simonw/datasette/issues/925"", ""label"": ""#925""}, {""href"": ""https://github.com/simonw/datasette/issues/926"", ""label"": ""#926""}]" changelog:id57,changelog,id57,0.46 (2020-08-09),"This release contains a security fix related to authenticated writable canned queries. If you are using this feature you should upgrade as soon as possible. Security fix: CSRF tokens were incorrectly included in read-only canned query forms, which could allow them to be leaked to a sophisticated attacker. See issue 918 for details. Datasette now supports GraphQL via the new datasette-graphql plugin - see GraphQL in Datasette with the new datasette-graphql plugin . Principle git branch has been renamed from master to main . ( #849 ) New debugging tool: /-/allow-debug tool ( demo here ) helps test allow blocks against actors, as described in Defining permissions with ""allow"" blocks . ( #908 ) New logo for the documentation, and a new project tagline: ""An open source multi-tool for exploring and publishing data"". Whitespace in column values is now respected on display, using white-space: pre-wrap . ( #896 ) New await request.post_body() method for accessing the raw POST body, see Request object . ( #897 ) Database file downloads now include a content-length HTTP header, enabling download progress bars. ( #905 ) File downloads now also correctly set the suggested file name using a content-disposition HTTP header. ( #909 ) tests are now excluded from the Datasette package properly - thanks, abeyerpath. ( #456 ) The Datasette package published to PyPI now includes sdist as well as bdist_wheel . Better titles for canned query pages. ( #887 ) Now only loads Python files from a directory passed using the --plugins-dir option - thanks, Amjith Ramanujam. ( #890 ) New documentation section on Publishing to Vercel .","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/918"", ""label"": ""issue 918""}, {""href"": ""https://github.com/simonw/datasette-graphql"", ""label"": ""datasette-graphql""}, {""href"": ""https://simonwillison.net/2020/Aug/7/datasette-graphql/"", ""label"": ""GraphQL in Datasette with the new datasette-graphql plugin""}, {""href"": ""https://github.com/simonw/datasette/issues/849"", ""label"": ""#849""}, {""href"": ""https://latest.datasette.io/-/allow-debug"", ""label"": ""demo here""}, {""href"": ""https://github.com/simonw/datasette/issues/908"", ""label"": ""#908""}, {""href"": ""https://github.com/simonw/datasette/issues/896"", ""label"": ""#896""}, {""href"": ""https://github.com/simonw/datasette/issues/897"", ""label"": ""#897""}, {""href"": ""https://github.com/simonw/datasette/issues/905"", ""label"": ""#905""}, {""href"": ""https://github.com/simonw/datasette/issues/909"", ""label"": ""#909""}, {""href"": ""https://github.com/simonw/datasette/issues/456"", ""label"": ""#456""}, {""href"": ""https://github.com/simonw/datasette/issues/887"", ""label"": ""#887""}, {""href"": ""https://github.com/simonw/datasette/pull/890"", ""label"": ""#890""}]" changelog:id58,changelog,id58,0.45 (2020-07-01),"See also Datasette 0.45: The annotated release notes . Magic parameters for canned queries, a log out feature, improved plugin documentation and four new plugin hooks.","[""Changelog""]","[{""href"": ""https://simonwillison.net/2020/Jul/1/datasette-045/"", ""label"": ""Datasette 0.45: The annotated release notes""}]" changelog:id59,changelog,id59,Smaller changes,"Cascading view permissions - so if a user has view-table they can view the table page even if they do not have view-database or view-instance . ( #832 ) CSRF protection no longer applies to Authentication: Bearer token requests or requests without cookies. ( #835 ) datasette.add_message() now works inside plugins. ( #864 ) Workaround for ""Too many open files"" error in test runs. ( #846 ) Respect existing scope[""actor""] if already set by ASGI middleware. ( #854 ) New process for shipping Alpha and beta releases . ( #807 ) {{ csrftoken() }} now works when plugins render a template using datasette.render_template(..., request=request) . ( #863 ) Datasette now creates a single Request object and uses it throughout the lifetime of the current HTTP request. ( #870 )","[""Changelog"", ""0.45 (2020-07-01)""]","[{""href"": ""https://github.com/simonw/datasette/issues/832"", ""label"": ""#832""}, {""href"": ""https://github.com/simonw/datasette/issues/835"", ""label"": ""#835""}, {""href"": ""https://github.com/simonw/datasette/issues/864"", ""label"": ""#864""}, {""href"": ""https://github.com/simonw/datasette/issues/846"", ""label"": ""#846""}, {""href"": ""https://github.com/simonw/datasette/issues/854"", ""label"": ""#854""}, {""href"": ""https://github.com/simonw/datasette/issues/807"", ""label"": ""#807""}, {""href"": ""https://github.com/simonw/datasette/issues/863"", ""label"": ""#863""}, {""href"": ""https://github.com/simonw/datasette/issues/870"", ""label"": ""#870""}]" changelog:id6,changelog,id6,0.64.1 (2023-01-11),"Documentation now links to a current source of information for installing Python 3. ( #1987 ) Incorrectly calling the Datasette constructor using Datasette(""path/to/data.db"") instead of Datasette([""path/to/data.db""]) now returns a useful error message. ( #1985 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/1987"", ""label"": ""#1987""}, {""href"": ""https://github.com/simonw/datasette/issues/1985"", ""label"": ""#1985""}]" changelog:id60,changelog,id60,0.44 (2020-06-11),"See also Datasette 0.44: The annotated release notes . Authentication and permissions, writable canned queries, flash messages, new plugin hooks and more.","[""Changelog""]","[{""href"": ""https://simonwillison.net/2020/Jun/12/annotated-release-notes/"", ""label"": ""Datasette 0.44: The annotated release notes""}]" changelog:id61,changelog,id61,Smaller changes,"New internals documentation for Request object and Response class . ( #706 ) request.url now respects the force_https_urls config setting. closes ( #781 ) request.args.getlist() returns [] if missing. Removed request.raw_args entirely. ( #774 ) New datasette.get_database() method. Added _ prefix to many private, undocumented methods of the Datasette class. ( #576 ) Removed the db.get_outbound_foreign_keys() method which duplicated the behaviour of db.foreign_keys_for_table() . New await datasette.permission_allowed() method. /-/actor debugging endpoint for viewing the currently authenticated actor. New request.cookies property. /-/plugins endpoint now shows a list of hooks implemented by each plugin, e.g. https://latest.datasette.io/-/plugins?all=1 request.post_vars() method no longer discards empty values. New ""params"" canned query key for explicitly setting named parameters, see Canned query parameters . ( #797 ) request.args is now a MultiParams object. Fixed a bug with the datasette plugins command. ( #802 ) Nicer pattern for using make_app_client() in tests. ( #395 ) New request.actor property. Fixed broken CSS on nested 404 pages. ( #777 ) New request.url_vars property. ( #822 ) Fixed a bug with the python tests/fixtures.py command for outputting Datasette's testing fixtures database and plugins. ( #804 ) datasette publish heroku now deploys using Python 3.8.3. Added a warning that the register_facet_classes() hook is unstable and may change in the future. ( #830 ) The {""$env"": ""ENVIRONMENT_VARIBALE""} mechanism (see Secret configuration values ) now works with variables inside nested lists. ( #837 )","[""Changelog"", ""0.44 (2020-06-11)""]","[{""href"": ""https://github.com/simonw/datasette/issues/706"", ""label"": ""#706""}, {""href"": ""https://github.com/simonw/datasette/issues/781"", ""label"": ""#781""}, {""href"": ""https://github.com/simonw/datasette/issues/774"", ""label"": ""#774""}, {""href"": ""https://github.com/simonw/datasette/issues/576"", ""label"": ""#576""}, {""href"": ""https://latest.datasette.io/-/plugins?all=1"", ""label"": ""https://latest.datasette.io/-/plugins?all=1""}, {""href"": ""https://github.com/simonw/datasette/issues/797"", ""label"": ""#797""}, {""href"": ""https://github.com/simonw/datasette/issues/802"", ""label"": ""#802""}, {""href"": ""https://github.com/simonw/datasette/issues/395"", ""label"": ""#395""}, {""href"": ""https://github.com/simonw/datasette/issues/777"", ""label"": ""#777""}, {""href"": ""https://github.com/simonw/datasette/issues/822"", ""label"": ""#822""}, {""href"": ""https://github.com/simonw/datasette/issues/804"", ""label"": ""#804""}, {""href"": ""https://github.com/simonw/datasette/issues/830"", ""label"": ""#830""}, {""href"": ""https://github.com/simonw/datasette/issues/837"", ""label"": ""#837""}]" changelog:id62,changelog,id62,0.43 (2020-05-28),"The main focus of this release is a major upgrade to the register_output_renderer(datasette) plugin hook, which allows plugins to provide new output formats for Datasette such as datasette-atom and datasette-ics . Redesign of register_output_renderer(datasette) to provide more context to the render callback and support an optional ""can_render"" callback that controls if a suggested link to the output format is provided. ( #581 , #770 ) Visually distinguish float and integer columns - useful for figuring out why order-by-column might be returning unexpected results. ( #729 ) The Request object , which is passed to several plugin hooks, is now documented. ( #706 ) New metadata.json option for setting a custom default page size for specific tables and views, see Setting a custom page size . ( #751 ) Canned queries can now be configured with a default URL fragment hash, useful when working with plugins such as datasette-vega , see Additional canned query options . ( #706 ) Fixed a bug in datasette publish when running on operating systems where the /tmp directory lives in a different volume, using a backport of the Python 3.8 shutil.copytree() function. ( #744 ) Every plugin hook is now covered by the unit tests, and a new unit test checks that each plugin hook has at least one corresponding test. ( #771 , #773 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette-atom"", ""label"": ""datasette-atom""}, {""href"": ""https://github.com/simonw/datasette-ics"", ""label"": ""datasette-ics""}, {""href"": ""https://github.com/simonw/datasette/issues/581"", ""label"": ""#581""}, {""href"": ""https://github.com/simonw/datasette/issues/770"", ""label"": ""#770""}, {""href"": ""https://github.com/simonw/datasette/issues/729"", ""label"": ""#729""}, {""href"": ""https://github.com/simonw/datasette/issues/706"", ""label"": ""#706""}, {""href"": ""https://github.com/simonw/datasette/issues/751"", ""label"": ""#751""}, {""href"": ""https://github.com/simonw/datasette-vega"", ""label"": ""datasette-vega""}, {""href"": ""https://github.com/simonw/datasette/issues/706"", ""label"": ""#706""}, {""href"": ""https://github.com/simonw/datasette/issues/744"", ""label"": ""#744""}, {""href"": ""https://github.com/simonw/datasette/issues/771"", ""label"": ""#771""}, {""href"": ""https://github.com/simonw/datasette/issues/773"", ""label"": ""#773""}]" changelog:id63,changelog,id63,0.42 (2020-05-08),"A small release which provides improved internal methods for use in plugins, along with documentation. See #685 . Added documentation for db.execute() , see await db.execute(sql, ...) . Renamed db.execute_against_connection_in_thread() to db.execute_fn() and made it a documented method, see await db.execute_fn(fn) . New results.first() and results.single_value() methods, plus documentation for the Results class - see Results .","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/685"", ""label"": ""#685""}]" changelog:id64,changelog,id64,0.41 (2020-05-06),"You can now create custom pages within your Datasette instance using a custom template file. For example, adding a template file called templates/pages/about.html will result in a new page being served at /about on your instance. See the custom pages documentation for full details, including how to return custom HTTP headers, redirects and status codes. ( #648 ) Configuration directory mode ( #731 ) allows you to define a custom Datasette instance as a directory. So instead of running the following: datasette one.db two.db \ --metadata=metadata.json \ --template-dir=templates/ \ --plugins-dir=plugins \ --static css:css You can instead arrange your files in a single directory called my-project and run this: datasette my-project/ Also in this release: New NOT LIKE table filter: ?colname__notlike=expression . ( #750 ) Datasette now has a pattern portfolio at /-/patterns - e.g. https://latest.datasette.io/-/patterns . This is a page that shows every Datasette user interface component in one place, to aid core development and people building custom CSS themes. ( #151 ) SQLite PRAGMA functions such as pragma_table_info(tablename) are now allowed in Datasette SQL queries. ( #761 ) Datasette pages now consistently return a content-type of text/html; charset=utf-8"" . ( #752 ) Datasette now handles an ASGI raw_path value of None , which should allow compatibility with the Mangum adapter for running ASGI apps on AWS Lambda. Thanks, Colin Dellow. ( #719 ) Installation documentation now covers how to Using pipx . ( #756 ) Improved the documentation for Full-text search . ( #748 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/648"", ""label"": ""#648""}, {""href"": ""https://github.com/simonw/datasette/issues/731"", ""label"": ""#731""}, {""href"": ""https://github.com/simonw/datasette/issues/750"", ""label"": ""#750""}, {""href"": ""https://latest.datasette.io/-/patterns"", ""label"": ""https://latest.datasette.io/-/patterns""}, {""href"": ""https://github.com/simonw/datasette/issues/151"", ""label"": ""#151""}, {""href"": ""https://www.sqlite.org/pragma.html#pragfunc"", ""label"": ""PRAGMA functions""}, {""href"": ""https://github.com/simonw/datasette/issues/761"", ""label"": ""#761""}, {""href"": ""https://github.com/simonw/datasette/issues/752"", ""label"": ""#752""}, {""href"": ""https://github.com/erm/mangum"", ""label"": ""Mangum""}, {""href"": ""https://github.com/simonw/datasette/pull/719"", ""label"": ""#719""}, {""href"": ""https://github.com/simonw/datasette/issues/756"", ""label"": ""#756""}, {""href"": ""https://github.com/simonw/datasette/issues/748"", ""label"": ""#748""}]" changelog:id65,changelog,id65,0.40 (2020-04-21),"Datasette Metadata can now be provided as a YAML file as an optional alternative to JSON. ( #713 ) Removed support for datasette publish now , which used the the now-retired Zeit Now v1 hosting platform. A new plugin, datasette-publish-now , can be installed to publish data to Zeit ( now Vercel ) Now v2. ( #710 ) Fixed a bug where the extra_template_vars(request, view_name) plugin hook was not receiving the correct view_name . ( #716 ) Variables added to the template context by the extra_template_vars() plugin hook are now shown in the ?_context=1 debugging mode (see template_debug ). ( #693 ) Fixed a bug where the ""templates considered"" HTML comment was no longer being displayed. ( #689 ) Fixed a datasette publish bug where --plugin-secret would over-ride plugin configuration in the provided metadata.json file. ( #724 ) Added a new CSS class for customizing the canned query page. ( #727 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/713"", ""label"": ""#713""}, {""href"": ""https://github.com/simonw/datasette-publish-now"", ""label"": ""datasette-publish-now""}, {""href"": ""https://vercel.com/blog/zeit-is-now-vercel"", ""label"": ""now Vercel""}, {""href"": ""https://github.com/simonw/datasette/issues/710"", ""label"": ""#710""}, {""href"": ""https://github.com/simonw/datasette/issues/716"", ""label"": ""#716""}, {""href"": ""https://github.com/simonw/datasette/issues/693"", ""label"": ""#693""}, {""href"": ""https://github.com/simonw/datasette/issues/689"", ""label"": ""#689""}, {""href"": ""https://github.com/simonw/datasette/issues/724"", ""label"": ""#724""}, {""href"": ""https://github.com/simonw/datasette/issues/727"", ""label"": ""#727""}]" changelog:id66,changelog,id66,0.39 (2020-03-24),"New base_url configuration setting for serving up the correct links while running Datasette under a different URL prefix. ( #394 ) New metadata settings ""sort"" and ""sort_desc"" for setting the default sort order for a table. See Setting a default sort order . ( #702 ) Sort direction arrow now displays by default on the primary key. This means you only have to click once (not twice) to sort in reverse order. ( #677 ) New await Request(scope, receive).post_vars() method for accessing POST form variables. ( #700 ) Plugin hooks documentation now links to example uses of each plugin. ( #709 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/394"", ""label"": ""#394""}, {""href"": ""https://github.com/simonw/datasette/issues/702"", ""label"": ""#702""}, {""href"": ""https://github.com/simonw/datasette/issues/677"", ""label"": ""#677""}, {""href"": ""https://github.com/simonw/datasette/issues/700"", ""label"": ""#700""}, {""href"": ""https://github.com/simonw/datasette/issues/709"", ""label"": ""#709""}]" changelog:id67,changelog,id67,0.38 (2020-03-08),"The Docker build of Datasette now uses SQLite 3.31.1, upgraded from 3.26. ( #695 ) datasette publish cloudrun now accepts an optional --memory=2Gi flag for setting the Cloud Run allocated memory to a value other than the default (256Mi). ( #694 ) Fixed bug where templates that shipped with plugins were sometimes not being correctly loaded. ( #697 )","[""Changelog""]","[{""href"": ""https://hub.docker.com/r/datasetteproject/datasette"", ""label"": ""Docker build""}, {""href"": ""https://github.com/simonw/datasette/issues/695"", ""label"": ""#695""}, {""href"": ""https://github.com/simonw/datasette/issues/694"", ""label"": ""#694""}, {""href"": ""https://github.com/simonw/datasette/issues/697"", ""label"": ""#697""}]" changelog:id68,changelog,id68,0.37.1 (2020-03-02),"Don't attempt to count table rows to display on the index page for databases > 100MB. ( #688 ) Print exceptions if they occur in the write thread rather than silently swallowing them. Handle the possibility of scope[""path""] being a string rather than bytes Better documentation for the extra_template_vars(template, database, table, columns, view_name, request, datasette) plugin hook.","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/688"", ""label"": ""#688""}]" changelog:id69,changelog,id69,0.37 (2020-02-25),"Plugins now have a supported mechanism for writing to a database, using the new .execute_write() and .execute_write_fn() methods. Documentation . ( #682 ) Immutable databases that have had their rows counted using the inspect command now use the calculated count more effectively - thanks, Kevin Keogh. ( #666 ) --reload no longer restarts the server if a database file is modified, unless that database was opened immutable mode with -i . ( #494 ) New ?_searchmode=raw option turns off escaping for FTS queries in ?_search= allowing full use of SQLite's FTS5 query syntax . ( #676 )","[""Changelog""]","[{""href"": ""https://github.com/simonw/datasette/issues/682"", ""label"": ""#682""}, {""href"": ""https://github.com/simonw/datasette/pull/666"", ""label"": ""#666""}, {""href"": ""https://github.com/simonw/datasette/issues/494"", ""label"": ""#494""}, {""href"": ""https://www.sqlite.org/fts5.html#full_text_query_syntax"", ""label"": ""FTS5 query syntax""}, {""href"": ""https://github.com/simonw/datasette/issues/676"", ""label"": ""#676""}]" changelog:id7,changelog,id7,0.64 (2023-01-09),"Datasette now strongly recommends against allowing arbitrary SQL queries if you are using SpatiaLite . SpatiaLite includes SQL functions that could cause the Datasette server to crash. See SpatiaLite for more details. New default_allow_sql setting, providing an easier way to disable all arbitrary SQL execution by end users: datasette --setting default_allow_sql off . See also Controlling the ability to execute arbitrary SQL . ( #1409 ) Building a location to time zone API with SpatiaLite is a new Datasette tutorial showing how to safely use SpatiaLite to create a location to time zone API. New documentation about how to debug problems loading SQLite extensions . The error message shown when an extension cannot be loaded has also been improved. ( #1979 ) Fixed an accessibility issue: the If you are rendering templates using the await .render_template(template, context=None, request=None) method the csrftoken() helper will only work if you provide the request= argument to that method. If you forget to do this you will see the following error: form-urlencoded POST field did not match cookie You can selectively disable CSRF protection using the skip_csrf(datasette, scope) hook.","[""Internals for plugins""]","[{""href"": ""https://github.com/simonw/asgi-csrf"", ""label"": ""asgi-csrf""}]" internals:internals-database,internals,internals-database,Database class,"Instances of the Database class can be used to execute queries against attached SQLite databases, and to run introspection against their schemas.","[""Internals for plugins""]",[] internals:internals-database-introspection,internals,internals-database-introspection,Database introspection,"The Database class also provides properties and methods for introspecting the database. db.name - string The name of the database - usually the filename without the .db prefix. db.size - integer The size of the database file in bytes. 0 for :memory: databases. db.mtime_ns - integer or None The last modification time of the database file in nanoseconds since the epoch. None for :memory: databases. db.is_mutable - boolean Is this database mutable, and allowed to accept writes? db.is_memory - boolean Is this database an in-memory database? await db.attached_databases() - list of named tuples Returns a list of additional databases that have been connected to this database using the SQLite ATTACH command. Each named tuple has fields seq , name and file . await db.table_exists(table) - boolean Check if a table called table exists. await db.view_exists(view) - boolean Check if a view called view exists. await db.table_names() - list of strings List of names of tables in the database. await db.view_names() - list of strings List of names of views in the database. await db.table_columns(table) - list of strings Names of columns in a specific table. await db.table_column_details(table) - list of named tuples Full details of the columns in a specific table. Each column is represented by a Column named tuple with fields cid (integer representing the column position), name (string), type (string, e.g. REAL or VARCHAR(30) ), notnull (integer 1 or 0), default_value (string or None), is_pk (integer 1 or 0). await db.primary_keys(table) - list of strings Names of the columns that are part of the primary key for this table. await db.fts_table(table) - string or None The name of the FTS table associated with this table, if one exists. await db.label_column_for_table(table) - string or None The label column that is associated with this table - either automatically detected or using the ""label_column"" key from Metadata , see Specifying the label column for a table . await db.foreign_keys_for_table(table) - list of dictionaries Details of columns in this table which are foreign keys to other tables. A list of dictionaries where each dictionary is shaped like this: {""column"": string, ""other_table"": string, ""other_column"": string} . await db.hidden_table_names() - list of strings List of tables which Datasette ""hides"" by default - usually these are tables associated with SQLite's full-text search feature, the SpatiaLite extension or tables hidden using the Hiding tables feature. await db.get_table_definition(table) - string Returns the SQL definition for the table - the CREATE TABLE statement and any associated CREATE INDEX statements. await db.get_view_definition(view) - string Returns the SQL definition of the named view. await db.get_all_foreign_keys() - dictionary Dictionary representing both incoming and outgoing foreign keys for this table. It has two keys, ""incoming"" and ""outgoing"" , each of which is a list of dictionaries with keys ""column"" , ""other_table"" and ""other_column"" . For example: { ""incoming"": [], ""outgoing"": [ { ""other_table"": ""attraction_characteristic"", ""column"": ""characteristic_id"", ""other_column"": ""pk"", }, { ""other_table"": ""roadside_attractions"", ""column"": ""attraction_id"", ""other_column"": ""pk"", } ] }","[""Internals for plugins"", ""Database class""]",[] internals:internals-datasette,internals,internals-datasette,Datasette class,"This object is an instance of the Datasette class, passed to many plugin hooks as an argument called datasette . You can create your own instance of this - for example to help write tests for a plugin - like so: from datasette.app import Datasette # With no arguments a single in-memory database will be attached datasette = Datasette() # The files= argument can load files from disk datasette = Datasette(files=[""/path/to/my-database.db""]) # Pass metadata as a JSON dictionary like this datasette = Datasette( files=[""/path/to/my-database.db""], metadata={ ""databases"": { ""my-database"": { ""description"": ""This is my database"" } } }, ) Constructor parameters include: files=[...] - a list of database files to open immutables=[...] - a list of database files to open in immutable mode metadata={...} - a dictionary of Metadata config_dir=... - the configuration directory to use, stored in datasette.config_dir","[""Internals for plugins""]",[] internals:internals-datasette-client,internals,internals-datasette-client,datasette.client,"Plugins can make internal simulated HTTP requests to the Datasette instance within which they are running. This ensures that all of Datasette's external JSON APIs are also available to plugins, while avoiding the overhead of making an external HTTP call to access those APIs. The datasette.client object is a wrapper around the HTTPX Python library , providing an async-friendly API that is similar to the widely used Requests library . It offers the following methods: await datasette.client.get(path, **kwargs) - returns HTTPX Response Execute an internal GET request against that path. await datasette.client.post(path, **kwargs) - returns HTTPX Response Execute an internal POST request. Use data={""name"": ""value""} to pass form parameters. await datasette.client.options(path, **kwargs) - returns HTTPX Response Execute an internal OPTIONS request. await datasette.client.head(path, **kwargs) - returns HTTPX Response Execute an internal HEAD request. await datasette.client.put(path, **kwargs) - returns HTTPX Response Execute an internal PUT request. await datasette.client.patch(path, **kwargs) - returns HTTPX Response Execute an internal PATCH request. await datasette.client.delete(path, **kwargs) - returns HTTPX Response Execute an internal DELETE request. await datasette.client.request(method, path, **kwargs) - returns HTTPX Response Execute an internal request with the given HTTP method against that path. These methods can be used with datasette.urls - for example: table_json = ( await datasette.client.get( datasette.urls.table( ""fixtures"", ""facetable"", format=""json"" ) ) ).json() datasette.client methods automatically take the current base_url setting into account, whether or not you use the datasette.urls family of methods to construct the path. For documentation on available **kwargs options and the shape of the HTTPX Response object refer to the HTTPX Async documentation .","[""Internals for plugins"", ""Datasette class""]","[{""href"": ""https://www.python-httpx.org/"", ""label"": ""HTTPX Python library""}, {""href"": ""https://requests.readthedocs.io/"", ""label"": ""Requests library""}, {""href"": ""https://www.python-httpx.org/async/"", ""label"": ""HTTPX Async documentation""}]" internals:internals-datasette-urls,internals,internals-datasette-urls,datasette.urls,"The datasette.urls object contains methods for building URLs to pages within Datasette. Plugins should use this to link to pages, since these methods take into account any base_url configuration setting that might be in effect. datasette.urls.instance(format=None) Returns the URL to the Datasette instance root page. This is usually ""/"" . datasette.urls.path(path, format=None) Takes a path and returns the full path, taking base_url into account. For example, datasette.urls.path(""-/logout"") will return the path to the logout page, which will be ""/-/logout"" by default or /prefix-path/-/logout if base_url is set to /prefix-path/ datasette.urls.logout() Returns the URL to the logout page, usually ""/-/logout"" datasette.urls.static(path) Returns the URL of one of Datasette's default static assets, for example ""/-/static/app.css"" datasette.urls.static_plugins(plugin_name, path) Returns the URL of one of the static assets belonging to a plugin. datasette.urls.static_plugins(""datasette_cluster_map"", ""datasette-cluster-map.js"") would return ""/-/static-plugins/datasette_cluster_map/datasette-cluster-map.js"" datasette.urls.static(path) Returns the URL of one of Datasette's default static assets, for example ""/-/static/app.css"" datasette.urls.database(database_name, format=None) Returns the URL to a database page, for example ""/fixtures"" datasette.urls.table(database_name, table_name, format=None) Returns the URL to a table page, for example ""/fixtures/facetable"" datasette.urls.query(database_name, query_name, format=None) Returns the URL to a query page, for example ""/fixtures/pragma_cache_size"" These functions can be accessed via the {{ urls }} object in Datasette templates, for example: Homepage Fixtures database facetable table pragma_cache_size query Use the format=""json"" (or ""csv"" or other formats supported by plugins) arguments to get back URLs to the JSON representation. This is the path with .json added on the end. These methods each return a datasette.utils.PrefixedUrlString object, which is a subclass of the Python str type. This allows the logic that considers the base_url setting to detect if that prefix has already been applied to the path.","[""Internals for plugins"", ""Datasette class""]",[] internals:internals-internal,internals,internals-internal,Datasette's internal database,"Datasette maintains an ""internal"" SQLite database used for configuration, caching, and storage. Plugins can store configuration, settings, and other data inside this database. By default, Datasette will use a temporary in-memory SQLite database as the internal database, which is created at startup and destroyed at shutdown. Users of Datasette can optionally pass in a --internal flag to specify the path to a SQLite database to use as the internal database, which will persist internal data across Datasette instances. Datasette maintains tables called catalog_databases , catalog_tables , catalog_columns , catalog_indexes , catalog_foreign_keys with details of the attached databases and their schemas. These tables should not be considered a stable API - they may change between Datasette releases. The internal database is not exposed in the Datasette application by default, which means private data can safely be stored without worry of accidentally leaking information through the default Datasette interface and API. However, other plugins do have full read and write access to the internal database. Plugins can access this database by calling internal_db = datasette.get_internal_database() and then executing queries using the Database API . Plugin authors are asked to practice good etiquette when using the internal database, as all plugins use the same database to store data. For example: Use a unique prefix when creating tables, indices, and triggers in the internal database. If your plugin is called datasette-xyz , then prefix names with datasette_xyz_* . Avoid long-running write statements that may stall or block other plugins that are trying to write at the same time. Use temporary tables or shared in-memory attached databases when possible. Avoid implementing features that could expose private data stored in the internal database by other plugins.","[""Internals for plugins""]",[] internals:internals-multiparams,internals,internals-multiparams,The MultiParams class,"request.args is a MultiParams object - a dictionary-like object which provides access to query string parameters that may have multiple values. Consider the query string ?foo=1&foo=2&bar=3 - with two values for foo and one value for bar . request.args[key] - string Returns the first value for that key, or raises a KeyError if the key is missing. For the above example request.args[""foo""] would return ""1"" . request.args.get(key) - string or None Returns the first value for that key, or None if the key is missing. Pass a second argument to specify a different default, e.g. q = request.args.get(""q"", """") . request.args.getlist(key) - list of strings Returns the list of strings for that key. request.args.getlist(""foo"") would return [""1"", ""2""] in the above example. request.args.getlist(""bar"") would return [""3""] . If the key is missing an empty list will be returned. request.args.keys() - list of strings Returns the list of available keys - for the example this would be [""foo"", ""bar""] . key in request.args - True or False You can use if key in request.args to check if a key is present. for key in request.args - iterator This lets you loop through every available key. len(request.args) - integer Returns the number of keys.","[""Internals for plugins""]",[] internals:internals-request,internals,internals-request,Request object,"The request object is passed to various plugin hooks. It represents an incoming HTTP request. It has the following properties: .scope - dictionary The ASGI scope that was used to construct this request, described in the ASGI HTTP connection scope specification. .method - string The HTTP method for this request, usually GET or POST . .url - string The full URL for this request, e.g. https://latest.datasette.io/fixtures . .scheme - string The request scheme - usually https or http . .headers - dictionary (str -> str) A dictionary of incoming HTTP request headers. Header names have been converted to lowercase. .cookies - dictionary (str -> str) A dictionary of incoming cookies .host - string The host header from the incoming request, e.g. latest.datasette.io or localhost . .path - string The path of the request excluding the query string, e.g. /fixtures . .full_path - string The path of the request including the query string if one is present, e.g. /fixtures?sql=select+sqlite_version() . .query_string - string The query string component of the request, without the ? - e.g. name__contains=sam&age__gt=10 . .args - MultiParams An object representing the parsed query string parameters, see below. .url_vars - dictionary (str -> str) Variables extracted from the URL path, if that path was defined using a regular expression. See register_routes(datasette) . .actor - dictionary (str -> Any) or None The currently authenticated actor (see actors ), or None if the request is unauthenticated. The object also has two awaitable methods: await request.post_vars() - dictionary Returns a dictionary of form variables that were submitted in the request body via POST . Don't forget to read about CSRF protection ! await request.post_body() - bytes Returns the un-parsed body of a request submitted by POST - useful for things like incoming JSON data. And a class method that can be used to create fake request objects for use in tests: fake(path_with_query_string, method=""GET"", scheme=""http"", url_vars=None) Returns a Request instance for the specified path and method. For example: from datasette import Request from pprint import pprint request = Request.fake( ""/fixtures/facetable/"", url_vars={""database"": ""fixtures"", ""table"": ""facetable""}, ) pprint(request.scope) This outputs: {'http_version': '1.1', 'method': 'GET', 'path': '/fixtures/facetable/', 'query_string': b'', 'raw_path': b'/fixtures/facetable/', 'scheme': 'http', 'type': 'http', 'url_route': {'kwargs': {'database': 'fixtures', 'table': 'facetable'}}}","[""Internals for plugins""]","[{""href"": ""https://asgi.readthedocs.io/en/latest/specs/www.html#connection-scope"", ""label"": ""ASGI HTTP connection scope""}]" internals:internals-response,internals,internals-response,Response class,"The Response class can be returned from view functions that have been registered using the register_routes(datasette) hook. The Response() constructor takes the following arguments: body - string The body of the response. status - integer (optional) The HTTP status - defaults to 200. headers - dictionary (optional) A dictionary of extra HTTP headers, e.g. {""x-hello"": ""world""} . content_type - string (optional) The content-type for the response. Defaults to text/plain . For example: from datasette.utils.asgi import Response response = Response( ""This is XML"", content_type=""application/xml; charset=utf-8"", ) The quickest way to create responses is using the Response.text(...) , Response.html(...) , Response.json(...) or Response.redirect(...) helper methods: from datasette.utils.asgi import Response html_response = Response.html(""This is HTML"") json_response = Response.json({""this_is"": ""json""}) text_response = Response.text( ""This will become utf-8 encoded text"" ) # Redirects are served as 302, unless you pass status=301: redirect_response = Response.redirect( ""https://latest.datasette.io/"" ) Each of these responses will use the correct corresponding content-type - text/html; charset=utf-8 , application/json; charset=utf-8 or text/plain; charset=utf-8 respectively. Each of the helper methods take optional status= and headers= arguments, documented above.","[""Internals for plugins""]",[] internals:internals-response-asgi-send,internals,internals-response-asgi-send,Returning a response with .asgi_send(send),"In most cases you will return Response objects from your own view functions. You can also use a Response instance to respond at a lower level via ASGI, for example if you are writing code that uses the asgi_wrapper(datasette) hook. Create a Response object and then use await response.asgi_send(send) , passing the ASGI send function. For example: async def require_authorization(scope, receive, send): response = Response.text( ""401 Authorization Required"", headers={ ""www-authenticate"": 'Basic realm=""Datasette"", charset=""UTF-8""' }, status=401, ) await response.asgi_send(send)","[""Internals for plugins"", ""Response class""]",[] internals:internals-response-set-cookie,internals,internals-response-set-cookie,Setting cookies with response.set_cookie(),"To set cookies on the response, use the response.set_cookie(...) method. The method signature looks like this: def set_cookie( self, key, value="""", max_age=None, expires=None, path=""/"", domain=None, secure=False, httponly=False, samesite=""lax"", ): ... You can use this with datasette.sign() to set signed cookies. Here's how you would set the ds_actor cookie for use with Datasette authentication : response = Response.redirect(""/"") response.set_cookie( ""ds_actor"", datasette.sign({""a"": {""id"": ""cleopaws""}}, ""actor""), ) return response","[""Internals for plugins"", ""Response class""]",[] internals:internals-shortcuts,internals,internals-shortcuts,Import shortcuts,"The following commonly used symbols can be imported directly from the datasette module: from datasette import Response from datasette import Forbidden from datasette import NotFound from datasette import hookimpl from datasette import actor_matches_allow","[""Internals for plugins""]",[] internals:internals-tilde-encoding,internals,internals-tilde-encoding,Tilde encoding,"Datasette uses a custom encoding scheme in some places, called tilde encoding . This is primarily used for table names and row primary keys, to avoid any confusion between / characters in those values and the Datasette URLs that reference them. Tilde encoding uses the same algorithm as URL percent-encoding , but with the ~ tilde character used in place of % . Any character other than ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz0123456789_- will be replaced by the numeric equivalent preceded by a tilde. For example: / becomes ~2F . becomes ~2E % becomes ~25 ~ becomes ~7E Space becomes + polls/2022.primary becomes polls~2F2022~2Eprimary Note that the space character is a special case: it will be replaced with a + symbol. datasette.utils. tilde_encode s : str str Returns tilde-encoded string - for example /foo/bar -> ~2Ffoo~2Fbar datasette.utils. tilde_decode s : str str Decodes a tilde-encoded string, so ~2Ffoo~2Fbar -> /foo/bar","[""Internals for plugins"", ""The datasette.utils module""]","[{""href"": ""https://developer.mozilla.org/en-US/docs/Glossary/percent-encoding"", ""label"": ""URL percent-encoding""}]" internals:internals-tracer,internals,internals-tracer,datasette.tracer,"Running Datasette with --setting trace_debug 1 enables trace debug output, which can then be viewed by adding ?_trace=1 to the query string for any page. You can see an example of this at the bottom of latest.datasette.io/fixtures/facetable?_trace=1 . The JSON output shows full details of every SQL query that was executed to generate the page. The datasette-pretty-traces plugin can be installed to provide a more readable display of this information. You can see a demo of that here . You can add your own custom traces to the JSON output using the trace() context manager. This takes a string that identifies the type of trace being recorded, and records any keyword arguments as additional JSON keys on the resulting trace object. The start and end time, duration and a traceback of where the trace was executed will be automatically attached to the JSON object. This example uses trace to record the start, end and duration of any HTTP GET requests made using the function: from datasette.tracer import trace import httpx async def fetch_url(url): with trace(""fetch-url"", url=url): async with httpx.AsyncClient() as client: return await client.get(url)","[""Internals for plugins""]","[{""href"": ""https://latest.datasette.io/fixtures/facetable?_trace=1"", ""label"": ""latest.datasette.io/fixtures/facetable?_trace=1""}, {""href"": ""https://datasette.io/plugins/datasette-pretty-traces"", ""label"": ""datasette-pretty-traces""}, {""href"": ""https://latest-with-plugins.datasette.io/github/commits?_trace=1"", ""label"": ""a demo of that here""}]" internals:internals-tracer-trace-child-tasks,internals,internals-tracer-trace-child-tasks,Tracing child tasks,"If your code uses a mechanism such as asyncio.gather() to execute code in additional tasks you may find that some of the traces are missing from the display. You can use the trace_child_tasks() context manager to ensure these child tasks are correctly handled. from datasette import tracer with tracer.trace_child_tasks(): results = await asyncio.gather( # ... async tasks here ) This example uses the register_routes() plugin hook to add a page at /parallel-queries which executes two SQL queries in parallel using asyncio.gather() and returns their results. from datasette import hookimpl from datasette import tracer @hookimpl def register_routes(): async def parallel_queries(datasette): db = datasette.get_database() with tracer.trace_child_tasks(): one, two = await asyncio.gather( db.execute(""select 1""), db.execute(""select 2""), ) return Response.json( { ""one"": one.single_value(), ""two"": two.single_value(), } ) return [ (r""/parallel-queries$"", parallel_queries), ] Note that running parallel SQL queries in this way has been known to cause problems in the past , so treat this example with caution. Adding ?_trace=1 will show that the trace covers both of those child tasks.","[""Internals for plugins"", ""datasette.tracer""]","[{""href"": ""https://github.com/simonw/datasette/issues/2189"", ""label"": ""been known to cause problems in the past""}]" internals:internals-utils,internals,internals-utils,The datasette.utils module,"The datasette.utils module contains various utility functions used by Datasette. As a general rule you should consider anything in this module to be unstable - functions and classes here could change without warning or be removed entirely between Datasette releases, without being mentioned in the release notes. The exception to this rule is anything that is documented here. If you find a need for an undocumented utility function in your own work, consider opening an issue requesting that the function you are using be upgraded to documented and supported status.","[""Internals for plugins""]","[{""href"": ""https://github.com/simonw/datasette/issues/new"", ""label"": ""opening an issue""}]" internals:internals-utils-await-me-maybe,internals,internals-utils-await-me-maybe,await_me_maybe(value),"Utility function for calling await on a return value if it is awaitable, otherwise returning the value. This is used by Datasette to support plugin hooks that can optionally return awaitable functions. Read more about this function in The “await me maybe” pattern for Python asyncio . async datasette.utils. await_me_maybe value : Any Any If value is callable, call it. If awaitable, await it. Otherwise return it.","[""Internals for plugins"", ""The datasette.utils module""]","[{""href"": ""https://simonwillison.net/2020/Sep/2/await-me-maybe/"", ""label"": ""The “await me maybe” pattern for Python asyncio""}]" internals:internals-utils-derive-named-parameters,internals,internals-utils-derive-named-parameters,"derive_named_parameters(db, sql)","Derive the list of named parameters referenced in a SQL query, using an explain query executed against the provided database. async datasette.utils. derive_named_parameters db : Database sql : str List [ str ] Given a SQL statement, return a list of named parameters that are used in the statement e.g. for select * from foo where id=:id this would return [""id""]","[""Internals for plugins"", ""The datasette.utils module""]",[] internals:internals-utils-parse-metadata,internals,internals-utils-parse-metadata,parse_metadata(content),"This function accepts a string containing either JSON or YAML, expected to be of the format described in Metadata . It returns a nested Python dictionary representing the parsed data from that string. If the metadata cannot be parsed as either JSON or YAML the function will raise a utils.BadMetadataError exception. datasette.utils. parse_metadata content : str dict Detects if content is JSON or YAML and parses it appropriately.","[""Internals for plugins"", ""The datasette.utils module""]",[] introspection:id1,introspection,id1,Introspection,"Datasette includes some pages and JSON API endpoints for introspecting the current instance. These can be used to understand some of the internals of Datasette and to see how a particular instance has been configured. Each of these pages can be viewed in your browser. Add .json to the URL to get back the contents as JSON.",[],[] introspection:jsondataview-actor,introspection,jsondataview-actor,/-/actor,"Shows the currently authenticated actor. Useful for debugging Datasette authentication plugins. { ""actor"": { ""id"": 1, ""username"": ""some-user"" } }","[""Introspection""]",[] introspection:jsondataview-config,introspection,jsondataview-config,/-/config,"Shows the configuration for this instance of Datasette. This is generally the contents of the datasette.yaml or datasette.json file, which can include plugin configuration as well. Config example : { ""settings"": { ""template_debug"": true, ""trace_debug"": true, ""force_https_urls"": true } } Any keys that include the one of the following substrings in their names will be returned as redacted *** output, to help avoid accidentally leaking private configuration information: secret , key , password , token , hash , dsn .","[""Introspection""]","[{""href"": ""https://latest.datasette.io/-/config"", ""label"": ""Config example""}]" introspection:jsondataview-databases,introspection,jsondataview-databases,/-/databases,"Shows currently attached databases. Databases example : [ { ""hash"": null, ""is_memory"": false, ""is_mutable"": true, ""name"": ""fixtures"", ""path"": ""fixtures.db"", ""size"": 225280 } ]","[""Introspection""]","[{""href"": ""https://latest.datasette.io/-/databases"", ""label"": ""Databases example""}]" introspection:jsondataview-metadata,introspection,jsondataview-metadata,/-/metadata,"Shows the contents of the metadata.json file that was passed to datasette serve , if any. Metadata example : { ""license"": ""CC Attribution 4.0 License"", ""license_url"": ""http://creativecommons.org/licenses/by/4.0/"", ""source"": ""fivethirtyeight/data on GitHub"", ""source_url"": ""https://github.com/fivethirtyeight/data"", ""title"": ""Five Thirty Eight"", ""databases"": { } }","[""Introspection""]","[{""href"": ""https://fivethirtyeight.datasettes.com/-/metadata"", ""label"": ""Metadata example""}]" introspection:jsondataview-plugins,introspection,jsondataview-plugins,/-/plugins,"Shows a list of currently installed plugins and their versions. Plugins example : [ { ""name"": ""datasette_cluster_map"", ""static"": true, ""templates"": false, ""version"": ""0.10"", ""hooks"": [""extra_css_urls"", ""extra_js_urls"", ""extra_body_script""] } ] Add ?all=1 to include details of the default plugins baked into Datasette.","[""Introspection""]","[{""href"": ""https://san-francisco.datasettes.com/-/plugins"", ""label"": ""Plugins example""}]" introspection:jsondataview-settings,introspection,jsondataview-settings,/-/settings,"Shows the Settings for this instance of Datasette. Settings example : { ""default_facet_size"": 30, ""default_page_size"": 100, ""facet_suggest_time_limit_ms"": 50, ""facet_time_limit_ms"": 1000, ""max_returned_rows"": 1000, ""sql_time_limit_ms"": 1000 }","[""Introspection""]","[{""href"": ""https://fivethirtyeight.datasettes.com/-/settings"", ""label"": ""Settings example""}]" introspection:jsondataview-threads,introspection,jsondataview-threads,/-/threads,"Shows details of threads and asyncio tasks. Threads example : { ""num_threads"": 2, ""threads"": [ { ""daemon"": false, ""ident"": 4759197120, ""name"": ""MainThread"" }, { ""daemon"": true, ""ident"": 123145319682048, ""name"": ""Thread-1"" }, ], ""num_tasks"": 3, ""tasks"": [ "" cb=[set.discard()]>"", "" wait_for=()]> cb=[run_until_complete..()]>"", "" wait_for=()]>>"" ] }","[""Introspection""]","[{""href"": ""https://latest.datasette.io/-/threads"", ""label"": ""Threads example""}]" introspection:jsondataview-versions,introspection,jsondataview-versions,/-/versions,"Shows the version of Datasette, Python and SQLite. Versions example : { ""datasette"": { ""version"": ""0.60"" }, ""python"": { ""full"": ""3.8.12 (default, Dec 21 2021, 10:45:09) \n[GCC 10.2.1 20210110]"", ""version"": ""3.8.12"" }, ""sqlite"": { ""extensions"": { ""json1"": null }, ""fts_versions"": [ ""FTS5"", ""FTS4"", ""FTS3"" ], ""compile_options"": [ ""COMPILER=gcc-6.3.0 20170516"", ""ENABLE_FTS3"", ""ENABLE_FTS4"", ""ENABLE_FTS5"", ""ENABLE_JSON1"", ""ENABLE_RTREE"", ""THREADSAFE=1"" ], ""version"": ""3.37.0"" } }","[""Introspection""]","[{""href"": ""https://latest.datasette.io/-/versions"", ""label"": ""Versions example""}]" introspection:messagesdebugview,introspection,messagesdebugview,/-/messages,"The debug tool at /-/messages can be used to set flash messages to try out that feature. See .add_message(request, message, type=datasette.INFO) for details of this feature.","[""Introspection""]",[] javascript_plugins:id1,javascript_plugins,id1,JavaScript plugins,"Datasette can run custom JavaScript in several different ways: Datasette plugins written in Python can use the extra_js_urls() or extra_body_script() plugin hooks to inject JavaScript into a page Datasette instances with custom templates can include additional JavaScript in those templates The extra_js_urls key in datasette.yaml can be used to include extra JavaScript There are no limitations on what this JavaScript can do. It is executed directly by the browser, so it can manipulate the DOM, fetch additional data and do anything else that JavaScript is capable of. Custom JavaScript has security implications, especially for authenticated Datasette instances where the JavaScript might run in the context of the authenticated user. It's important to carefully review any JavaScript you run in your Datasette instance.",[],[] javascript_plugins:id2,javascript_plugins,id2,JavaScript plugin objects,"JavaScript plugins are blocks of code that can be registered with Datasette using the registerPlugin() method on the datasetteManager object. The implementation object passed to this method should include a version key defining the plugin version, and one or more of the following named functions providing the implementation of the plugin:","[""JavaScript plugins""]",[] javascript_plugins:javascript-datasette-init,javascript_plugins,javascript-datasette-init,The datasette_init event,"Datasette emits a custom event called datasette_init when the page is loaded. This event is dispatched on the document object, and includes a detail object with a reference to the datasetteManager object. Your JavaScript code can listen out for this event using document.addEventListener() like this: document.addEventListener(""datasette_init"", function (evt) { const manager = evt.detail; console.log(""Datasette version:"", manager.VERSION); });","[""JavaScript plugins""]",[] javascript_plugins:javascript-datasette-manager,javascript_plugins,javascript-datasette-manager,datasetteManager,"The datasetteManager object VERSION - string The version of Datasette plugins - Map() A Map of currently loaded plugin names to plugin implementations registerPlugin(name, implementation) Call this to register a plugin, passing its name and implementation selectors - object An object providing named aliases to useful CSS selectors, listed below","[""JavaScript plugins""]",[] javascript_plugins:javascript-datasette-manager-selectors,javascript_plugins,javascript-datasette-manager-selectors,Selectors,"These are available on the selectors property of the datasetteManager object. const DOM_SELECTORS = { /** Should have one match */ jsonExportLink: "".export-links a[href*=json]"", /** Event listeners that go outside of the main table, e.g. existing scroll listener */ tableWrapper: "".table-wrapper"", table: ""table.rows-and-columns"", aboveTablePanel: "".above-table-panel"", // These could have multiple matches /** Used for selecting table headers. Use makeColumnActions if you want to add menu items. */ tableHeaders: `table.rows-and-columns th`, /** Used to add ""where"" clauses to query using direct manipulation */ filterRows: "".filter-row"", /** Used to show top available enum values for a column (""facets"") */ facetResults: "".facet-results [data-column]"", };","[""JavaScript plugins""]",[] javascript_plugins:javascript-plugins-makeabovetablepanelconfigs,javascript_plugins,javascript-plugins-makeabovetablepanelconfigs,makeAboveTablePanelConfigs(),"This method should return a JavaScript array of objects defining additional panels to be added to the top of the table page. Each object should have the following: id - string A unique string ID for the panel, for example map-panel label - string A human-readable label for the panel render(node) - function A function that will be called with a DOM node to render the panel into This example shows how a plugin might define a single panel: document.addEventListener('datasette_init', function(ev) { ev.detail.registerPlugin('panel-plugin', { version: 0.1, makeAboveTablePanelConfigs: () => { return [ { id: 'first-panel', label: 'First panel', render: node => { node.innerHTML = '

My custom panel

This is a custom panel that I added using a JavaScript plugin

'; } } ] } }); }); When a page with a table loads, all registered plugins that implement makeAboveTablePanelConfigs() will be called and panels they return will be added to the top of the table page.","[""JavaScript plugins"", ""JavaScript plugin objects""]",[] javascript_plugins:javascript-plugins-makecolumnactions,javascript_plugins,javascript-plugins-makecolumnactions,makeColumnActions(columnDetails),"This method, if present, will be called when Datasette is rendering the cog action menu icons that appear at the top of the table view. By default these include options like ""Sort ascending/descending"" and ""Facet by this"", but plugins can return additional actions to be included in this menu. The method will be called with a columnDetails object with the following keys: columnName - string The name of the column columnNotNull - boolean True if the column is defined as NOT NULL columnType - string The SQLite data type of the column isPk - boolean True if the column is part of the primary key It should return a JavaScript array of objects each with a label and onClick property: label - string The human-readable label for the action onClick(evt) - function A function that will be called when the action is clicked The evt object passed to the onClick is the standard browser event object that triggered the click. This example plugin adds two menu items - one to copy the column name to the clipboard and another that displays the column metadata in an alert() window: document.addEventListener('datasette_init', function(ev) { ev.detail.registerPlugin('column-name-plugin', { version: 0.1, makeColumnActions: (columnDetails) => { return [ { label: 'Copy column to clipboard', onClick: async (evt) => { await navigator.clipboard.writeText(columnDetails.columnName) } }, { label: 'Alert column metadata', onClick: () => alert(JSON.stringify(columnDetails, null, 2)) } ]; } }); });","[""JavaScript plugins"", ""JavaScript plugin objects""]",[] json_api:column-filter-arguments,json_api,column-filter-arguments,Column filter arguments,"You can filter the data returned by the table based on column values using a query string argument. ?column__exact=value or ?_column=value Returns rows where the specified column exactly matches the value. ?column__not=value Returns rows where the column does not match the value. ?column__contains=value Rows where the string column contains the specified value ( column like ""%value%"" in SQL). ?column__notcontains=value Rows where the string column does not contain the specified value ( column not like ""%value%"" in SQL). ?column__endswith=value Rows where the string column ends with the specified value ( column like ""%value"" in SQL). ?column__startswith=value Rows where the string column starts with the specified value ( column like ""value%"" in SQL). ?column__gt=value Rows which are greater than the specified value. ?column__gte=value Rows which are greater than or equal to the specified value. ?column__lt=value Rows which are less than the specified value. ?column__lte=value Rows which are less than or equal to the specified value. ?column__like=value Match rows with a LIKE clause, case insensitive and with % as the wildcard character. ?column__notlike=value Match rows that do not match the provided LIKE clause. ?column__glob=value Similar to LIKE but uses Unix wildcard syntax and is case sensitive. ?column__in=value1,value2,value3 Rows where column matches any of the provided values. You can use a comma separated string, or you can use a JSON array. The JSON array option is useful if one of your matching values itself contains a comma: ?column__in=[""value"",""value,with,commas""] ?column__notin=value1,value2,value3 Rows where column does not match any of the provided values. The inverse of __in= . Also supports JSON arrays. ?column__arraycontains=value Works against columns that contain JSON arrays - matches if any of the values in that array match the provided value. This is only available if the json1 SQLite extension is enabled. ?column__arraynotcontains=value Works against columns that contain JSON arrays - matches if none of the values in that array match the provided value. This is only available if the json1 SQLite extension is enabled. ?column__date=value Column is a datestamp occurring on the specified YYYY-MM-DD date, e.g. 2018-01-02 . ?column__isnull=1 Matches rows where the column is null. ?column__notnull=1 Matches rows where the column is not null. ?column__isblank=1 Matches rows where the column is blank, meaning null or the empty string. ?column__notblank=1 Matches rows where the column is not blank.","[""JSON API"", ""Table arguments""]",[] json_api:expand-foreign-keys,json_api,expand-foreign-keys,Expanding foreign key references,"Datasette can detect foreign key relationships and resolve those references into labels. The HTML interface does this by default for every detected foreign key column - you can turn that off using ?_labels=off . You can request foreign keys be expanded in JSON using the _labels=on or _label=COLUMN special query string parameters. Here's what an expanded row looks like: [ { ""rowid"": 1, ""TreeID"": 141565, ""qLegalStatus"": { ""value"": 1, ""label"": ""Permitted Site"" }, ""qSpecies"": { ""value"": 1, ""label"": ""Myoporum laetum :: Myoporum"" }, ""qAddress"": ""501X Baker St"", ""SiteOrder"": 1 } ] The column in the foreign key table that is used for the label can be specified in metadata.json - see Specifying the label column for a table .","[""JSON API""]",[] json_api:id1,json_api,id1,JSON API,"Datasette provides a JSON API for your SQLite databases. Anything you can do through the Datasette user interface can also be accessed as JSON via the API. To access the API for a page, either click on the .json link on that page or edit the URL and add a .json extension to it.",[],[] json_api:id2,json_api,id2,Table arguments,The Datasette table view takes a number of special query string arguments.,"[""JSON API""]",[] json_api:json-api-cors,json_api,json-api-cors,Enabling CORS,"If you start Datasette with the --cors option, each JSON endpoint will be served with the following additional HTTP headers: [[[cog from datasette.utils import add_cors_headers import textwrap headers = {} add_cors_headers(headers) output = ""\n"".join(""{}: {}"".format(k, v) for k, v in headers.items()) cog.out(""\n::\n\n"") cog.out(textwrap.indent(output, ' ')) cog.out(""\n\n"") ]]] Access-Control-Allow-Origin: * Access-Control-Allow-Headers: Authorization, Content-Type Access-Control-Expose-Headers: Link Access-Control-Allow-Methods: GET, POST, HEAD, OPTIONS Access-Control-Max-Age: 3600 [[[end]]] This allows JavaScript running on any domain to make cross-origin requests to interact with the Datasette API. If you start Datasette without the --cors option only JavaScript running on the same domain as Datasette will be able to access the API. Here's how to serve data.db with CORS enabled: datasette data.db --cors","[""JSON API""]",[] json_api:json-api-default,json_api,json-api-default,Default representation,"The default JSON representation of data from a SQLite table or custom query looks like this: { ""ok"": true, ""rows"": [ { ""id"": 3, ""name"": ""Detroit"" }, { ""id"": 2, ""name"": ""Los Angeles"" }, { ""id"": 4, ""name"": ""Memnonia"" }, { ""id"": 1, ""name"": ""San Francisco"" } ], ""truncated"": false } ""ok"" is always true if an error did not occur. The ""rows"" key is a list of objects, each one representing a row. The ""truncated"" key lets you know if the query was truncated. This can happen if a SQL query returns more than 1,000 results (or the max_returned_rows setting). For table pages, an additional key ""next"" may be present. This indicates that the next page in the pagination set can be retrieved using ?_next=VALUE .","[""JSON API""]",[] json_api:json-api-discover-alternate,json_api,json-api-discover-alternate,Discovering the JSON for a page,"Most of the HTML pages served by Datasette provide a mechanism for discovering their JSON equivalents using the HTML link mechanism. You can find this near the top of the source code of those pages, looking like this: The JSON URL is also made available in a Link HTTP header for the page: Link: https://latest.datasette.io/fixtures/sortable.json; rel=""alternate""; type=""application/json+datasette""","[""JSON API""]",[] json_api:json-api-pagination,json_api,json-api-pagination,Pagination,"The default JSON representation includes a ""next_url"" key which can be used to access the next page of results. If that key is null or missing then it means you have reached the final page of results. Other representations include pagination information in the link HTTP header. That header will look something like this: link: ; rel=""next"" Here is an example Python function built using requests that returns a list of all of the paginated items from one of these API endpoints: def paginate(url): items = [] while url: response = requests.get(url) try: url = response.links.get(""next"").get(""url"") except AttributeError: url = None items.extend(response.json()) return items","[""JSON API""]","[{""href"": ""https://requests.readthedocs.io/"", ""label"": ""requests""}]" json_api:json-api-shapes,json_api,json-api-shapes,Different shapes,"The _shape parameter can be used to access alternative formats for the rows key which may be more convenient for your application. There are three options: ?_shape=objects - ""rows"" is a list of JSON key/value objects - the default ?_shape=arrays - ""rows"" is a list of lists, where the order of values in each list matches the order of the columns ?_shape=array - a JSON array of objects - effectively just the ""rows"" key from the default representation ?_shape=array&_nl=on - a newline-separated list of JSON objects ?_shape=arrayfirst - a flat JSON array containing just the first value from each row ?_shape=object - a JSON object keyed using the primary keys of the rows _shape=arrays looks like this: { ""ok"": true, ""next"": null, ""rows"": [ [3, ""Detroit""], [2, ""Los Angeles""], [4, ""Memnonia""], [1, ""San Francisco""] ] } _shape=array looks like this: [ { ""id"": 3, ""name"": ""Detroit"" }, { ""id"": 2, ""name"": ""Los Angeles"" }, { ""id"": 4, ""name"": ""Memnonia"" }, { ""id"": 1, ""name"": ""San Francisco"" } ] _shape=array&_nl=on looks like this: {""id"": 1, ""value"": ""Myoporum laetum :: Myoporum""} {""id"": 2, ""value"": ""Metrosideros excelsa :: New Zealand Xmas Tree""} {""id"": 3, ""value"": ""Pinus radiata :: Monterey Pine""} _shape=arrayfirst looks like this: [1, 2, 3] _shape=object looks like this: { ""1"": { ""id"": 1, ""value"": ""Myoporum laetum :: Myoporum"" }, ""2"": { ""id"": 2, ""value"": ""Metrosideros excelsa :: New Zealand Xmas Tree"" }, ""3"": { ""id"": 3, ""value"": ""Pinus radiata :: Monterey Pine"" } ] The object shape is only available for queries against tables - custom SQL queries and views do not have an obvious primary key so cannot be returned using this format. The object keys are always strings. If your table has a compound primary key, the object keys will be a comma-separated string.","[""JSON API""]",[] json_api:json-api-special,json_api,json-api-special,Special JSON arguments,"Every Datasette endpoint that can return JSON also accepts the following query string arguments: ?_shape=SHAPE The shape of the JSON to return, documented above. ?_nl=on When used with ?_shape=array produces newline-delimited JSON objects. ?_json=COLUMN1&_json=COLUMN2 If any of your SQLite columns contain JSON values, you can use one or more _json= parameters to request that those columns be returned as regular JSON. Without this argument those columns will be returned as JSON objects that have been double-encoded into a JSON string value. Compare this query without the argument to this query using the argument ?_json_infinity=on If your data contains infinity or -infinity values, Datasette will replace them with None when returning them as JSON. If you pass _json_infinity=1 Datasette will instead return them as Infinity or -Infinity which is invalid JSON but can be processed by some custom JSON parsers. ?_timelimit=MS Sets a custom time limit for the query in ms. You can use this for optimistic queries where you would like Datasette to give up if the query takes too long, for example if you want to implement autocomplete search but only if it can be executed in less than 10ms. ?_ttl=SECONDS For how many seconds should this response be cached by HTTP proxies? Use ?_ttl=0 to disable HTTP caching entirely for this request. ?_trace=1 Turns on tracing for this page: SQL queries executed during the request will be gathered and included in the response, either in a new ""_traces"" key for JSON responses or at the bottom of the page if the response is in HTML. The structure of the data returned here should be considered highly unstable and very likely to change. Only available if the trace_debug setting is enabled.","[""JSON API""]","[{""href"": ""https://fivethirtyeight.datasettes.com/fivethirtyeight.json?sql=select+%27{%22this+is%22%3A+%22a+json+object%22}%27+as+d&_shape=array"", ""label"": ""this query without the argument""}, {""href"": ""https://fivethirtyeight.datasettes.com/fivethirtyeight.json?sql=select+%27{%22this+is%22%3A+%22a+json+object%22}%27+as+d&_shape=array&_json=d"", ""label"": ""this query using the argument""}]" json_api:json-api-table-arguments,json_api,json-api-table-arguments,Special table arguments,"?_col=COLUMN1&_col=COLUMN2 List specific columns to display. These will be shown along with any primary keys. ?_nocol=COLUMN1&_nocol=COLUMN2 List specific columns to hide - any column not listed will be displayed. Primary keys cannot be hidden. ?_labels=on/off Expand foreign key references for every possible column. See below. ?_label=COLUMN1&_label=COLUMN2 Expand foreign key references for one or more specified columns. ?_size=1000 or ?_size=max Sets a custom page size. This cannot exceed the max_returned_rows limit passed to datasette serve . Use max to get max_returned_rows . ?_sort=COLUMN Sorts the results by the specified column. ?_sort_desc=COLUMN Sorts the results by the specified column in descending order. ?_search=keywords For SQLite tables that have been configured for full-text search executes a search with the provided keywords. ?_search_COLUMN=keywords Like _search= but allows you to specify the column to be searched, as opposed to searching all columns that have been indexed by FTS. ?_searchmode=raw With this option, queries passed to ?_search= or ?_search_COLUMN= will not have special characters escaped. This means you can make use of the full set of advanced SQLite FTS syntax , though this could potentially result in errors if the wrong syntax is used. ?_where=SQL-fragment If the execute-sql permission is enabled, this parameter can be used to pass one or more additional SQL fragments to be used in the WHERE clause of the SQL used to query the table. This is particularly useful if you are building a JavaScript application that needs to do something creative but still wants the other conveniences provided by the table view (such as faceting) and hence would like not to have to construct a completely custom SQL query. Some examples: facetable?_where=_neighborhood like ""%c%""&_where=_city_id=3 facetable?_where=_city_id in (select id from facet_cities where name != ""Detroit"") ?_through={json} This can be used to filter rows via a join against another table. The JSON parameter must include three keys: table , column and value . table must be a table that the current table is related to via a foreign key relationship. column must be a column in that other table. value is the value that you want to match against. For example, to filter roadside_attractions to just show the attractions that have a characteristic of ""museum"", you would construct this JSON: { ""table"": ""roadside_attraction_characteristics"", ""column"": ""characteristic_id"", ""value"": ""1"" } As a URL, that looks like this: ?_through={%22table%22:%22roadside_attraction_characteristics%22,%22column%22:%22characteristic_id%22,%22value%22:%221%22} Here's an example . ?_next=TOKEN Pagination by continuation token - pass the token that was returned in the ""next"" property by the previous page. ?_facet=column Facet by column. Can be applied multiple times, see Facets . Only works on the default JSON output, not on any of the custom shapes. ?_facet_size=100 Increase the number of facet results returned for each facet. Use ?_facet_size=max for the maximum available size, determined by max_returned_rows . ?_nofacet=1 Disable all facets and facet suggestions for this page, including any defined by Facets in metadata . ?_nosuggest=1 Disable facet suggestions for this page. ?_nocount=1 Disable the select count(*) query used on this page - a count of None will be returned instead.","[""JSON API"", ""Table arguments""]","[{""href"": ""https://www.sqlite.org/fts3.html"", ""label"": ""full-text search""}, {""href"": ""https://www.sqlite.org/fts5.html#full_text_query_syntax"", ""label"": ""advanced SQLite FTS syntax""}, {""href"": ""https://latest.datasette.io/fixtures/facetable?_where=_neighborhood%20like%20%22%c%%22&_where=_city_id=3"", ""label"": ""facetable?_where=_neighborhood like \""%c%\""&_where=_city_id=3""}, {""href"": ""https://latest.datasette.io/fixtures/facetable?_where=_city_id%20in%20(select%20id%20from%20facet_cities%20where%20name%20!=%20%22Detroit%22)"", ""label"": ""facetable?_where=_city_id in (select id from facet_cities where name != \""Detroit\"")""}, {""href"": ""https://latest.datasette.io/fixtures/roadside_attractions?_through={%22table%22:%22roadside_attraction_characteristics%22,%22column%22:%22characteristic_id%22,%22value%22:%221%22}"", ""label"": ""an example""}]" json_api:json-api-write,json_api,json-api-write,The JSON write API,"Datasette provides a write API for JSON data. This is a POST-only API that requires an authenticated API token, see API Tokens . The token will need to have the specified Permissions .","[""JSON API""]",[] json_api:rowdeleteview,json_api,rowdeleteview,Deleting a row,"To delete a row, make a POST to ////-/delete . This requires the delete-row permission. POST //
//-/delete Content-Type: application/json Authorization: Bearer dstok_ here is the tilde-encoded primary key value of the row to delete - or a comma-separated list of primary key values if the table has a composite primary key. If successful, this will return a 200 status code and a {""ok"": true} response body. Any errors will return {""errors"": [""... descriptive message ...""], ""ok"": false} , and a 400 status code for a bad input or a 403 status code for an authentication or permission error.","[""JSON API"", ""The JSON write API""]",[] json_api:rowupdateview,json_api,rowupdateview,Updating a row,"To update a row, make a POST to //
//-/update . This requires the update-row permission. POST //
//-/update Content-Type: application/json Authorization: Bearer dstok_ { ""update"": { ""text_column"": ""New text string"", ""integer_column"": 3, ""float_column"": 3.14 } } here is the tilde-encoded primary key value of the row to update - or a comma-separated list of primary key values if the table has a composite primary key. You only need to pass the columns you want to update. Any other columns will be left unchanged. If successful, this will return a 200 status code and a {""ok"": true} response body. Add ""return"": true to the request body to return the updated row: { ""update"": { ""title"": ""New title"" }, ""return"": true } The returned JSON will look like this: { ""ok"": true, ""row"": { ""id"": 1, ""title"": ""New title"", ""other_column"": ""Will be present here too"" } } Any errors will return {""errors"": [""... descriptive message ...""], ""ok"": false} , and a 400 status code for a bad input or a 403 status code for an authentication or permission error. Pass ""alter: true to automatically add any missing columns to the table. This requires the alter-table permission.","[""JSON API"", ""The JSON write API""]",[] json_api:tablecreateview,json_api,tablecreateview,Creating a table,"To create a table, make a POST to //-/create . This requires the create-table permission. POST //-/create Content-Type: application/json Authorization: Bearer dstok_ { ""table"": ""name_of_new_table"", ""columns"": [ { ""name"": ""id"", ""type"": ""integer"" }, { ""name"": ""title"", ""type"": ""text"" } ], ""pk"": ""id"" } The JSON here describes the table that will be created: table is the name of the table to create. This field is required. columns is a list of columns to create. Each column is a dictionary with name and type keys. name is the name of the column. This is required. type is the type of the column. This is optional - if not provided, text will be assumed. The valid types are text , integer , float and blob . pk is the primary key for the table. This is optional - if not provided, Datasette will create a SQLite table with a hidden rowid column. If the primary key is an integer column, it will be configured to automatically increment for each new record. If you set this to id without including an id column in the list of columns , Datasette will create an auto-incrementing integer ID column for you. pks can be used instead of pk to create a compound primary key. It should be a JSON list of column names to use in that primary key. ignore can be set to true to ignore existing rows by primary key if the table already exists. replace can be set to true to replace existing rows by primary key if the table already exists. This requires the update-row permission. alter can be set to true if you want to automatically add any missing columns to the table. This requires the alter-table permission. If the table is successfully created this will return a 201 status code and the following response: { ""ok"": true, ""database"": ""data"", ""table"": ""name_of_new_table"", ""table_url"": ""http://127.0.0.1:8001/data/name_of_new_table"", ""table_api_url"": ""http://127.0.0.1:8001/data/name_of_new_table.json"", ""schema"": ""CREATE TABLE [name_of_new_table] (\n [id] INTEGER PRIMARY KEY,\n [title] TEXT\n)"" }","[""JSON API"", ""The JSON write API""]",[] json_api:tablecreateview-example,json_api,tablecreateview-example,Creating a table from example data,"Instead of specifying columns directly you can instead pass a single example row or a list of rows . Datasette will create a table with a schema that matches those rows and insert them for you: POST //-/create Content-Type: application/json Authorization: Bearer dstok_ { ""table"": ""creatures"", ""rows"": [ { ""id"": 1, ""name"": ""Tarantula"" }, { ""id"": 2, ""name"": ""Kākāpō"" } ], ""pk"": ""id"" } Doing this requires both the create-table and insert-row permissions. The 201 response here will be similar to the columns form, but will also include the number of rows that were inserted as row_count : { ""ok"": true, ""database"": ""data"", ""table"": ""creatures"", ""table_url"": ""http://127.0.0.1:8001/data/creatures"", ""table_api_url"": ""http://127.0.0.1:8001/data/creatures.json"", ""schema"": ""CREATE TABLE [creatures] (\n [id] INTEGER PRIMARY KEY,\n [name] TEXT\n)"", ""row_count"": 2 } You can call the create endpoint multiple times for the same table provided you are specifying the table using the rows or row option. New rows will be inserted into the table each time. This means you can use this API if you are unsure if the relevant table has been created yet. If you pass a row to the create endpoint with a primary key that already exists you will get an error that looks like this: { ""ok"": false, ""errors"": [ ""UNIQUE constraint failed: creatures.id"" ] } You can avoid this error by passing the same ""ignore"": true or ""replace"": true options to the create endpoint as you can to the insert endpoint . To use the ""replace"": true option you will also need the update-row permission. Pass ""alter"": true to automatically add any missing columns to the existing table that are present in the rows you are submitting. This requires the alter-table permission.","[""JSON API"", ""The JSON write API""]",[] json_api:tabledropview,json_api,tabledropview,Dropping tables,"To drop a table, make a POST to //
/-/drop . This requires the drop-table permission. POST //
/-/drop Content-Type: application/json Authorization: Bearer dstok_ Without a POST body this will return a status 200 with a note about how many rows will be deleted: { ""ok"": true, ""database"": """", ""table"": ""
"", ""row_count"": 5, ""message"": ""Pass \""confirm\"": true to confirm"" } If you pass the following POST body: { ""confirm"": true } Then the table will be dropped and a status 200 response of {""ok"": true} will be returned. Any errors will return {""errors"": [""... descriptive message ...""], ""ok"": false} , and a 400 status code for a bad input or a 403 status code for an authentication or permission error.","[""JSON API"", ""The JSON write API""]",[] json_api:tableinsertview,json_api,tableinsertview,Inserting rows,"This requires the insert-row permission. A single row can be inserted using the ""row"" key: POST //
/-/insert Content-Type: application/json Authorization: Bearer dstok_ { ""row"": { ""column1"": ""value1"", ""column2"": ""value2"" } } If successful, this will return a 201 status code and the newly inserted row, for example: { ""rows"": [ { ""id"": 1, ""column1"": ""value1"", ""column2"": ""value2"" } ] } To insert multiple rows at a time, use the same API method but send a list of dictionaries as the ""rows"" key: POST //
/-/insert Content-Type: application/json Authorization: Bearer dstok_ { ""rows"": [ { ""column1"": ""value1"", ""column2"": ""value2"" }, { ""column1"": ""value3"", ""column2"": ""value4"" } ] } If successful, this will return a 201 status code and a {""ok"": true} response body. The maximum number rows that can be submitted at once defaults to 100, but this can be changed using the max_insert_rows setting. To return the newly inserted rows, add the ""return"": true key to the request body: { ""rows"": [ { ""column1"": ""value1"", ""column2"": ""value2"" }, { ""column1"": ""value3"", ""column2"": ""value4"" } ], ""return"": true } This will return the same ""rows"" key as the single row example above. There is a small performance penalty for using this option. If any of your rows have a primary key that is already in use, you will get an error and none of the rows will be inserted: { ""ok"": false, ""errors"": [ ""UNIQUE constraint failed: new_table.id"" ] } Pass ""ignore"": true to ignore these errors and insert the other rows: { ""rows"": [ { ""id"": 1, ""column1"": ""value1"", ""column2"": ""value2"" }, { ""id"": 2, ""column1"": ""value3"", ""column2"": ""value4"" } ], ""ignore"": true } Or you can pass ""replace"": true to replace any rows with conflicting primary keys with the new values. This requires the update-row permission. Pass ""alter: true to automatically add any missing columns to the table. This requires the alter-table permission.","[""JSON API"", ""The JSON write API""]",[] json_api:tableupsertview,json_api,tableupsertview,Upserting rows,"An upsert is an insert or update operation. If a row with a matching primary key already exists it will be updated - otherwise a new row will be inserted. The upsert API is mostly the same shape as the insert API . It requires both the insert-row and update-row permissions. POST //
/-/upsert Content-Type: application/json Authorization: Bearer dstok_ { ""rows"": [ { ""id"": 1, ""title"": ""Updated title for 1"", ""description"": ""Updated description for 1"" }, { ""id"": 2, ""description"": ""Updated description for 2"", }, { ""id"": 3, ""title"": ""Item 3"", ""description"": ""Description for 3"" } ] } Imagine a table with a primary key of id and which already has rows with id values of 1 and 2 . The above example will: Update the row with id of 1 to set both title and description to the new values Update the row with id of 2 to set title to the new value - description will be left unchanged Insert a new row with id of 3 and both title and description set to the new values Similar to /-/insert , a row key with an object can be used instead of a rows array to upsert a single row. If successful, this will return a 200 status code and a {""ok"": true} response body. Add ""return"": true to the request body to return full copies of the affected rows after they have been inserted or updated: { ""rows"": [ { ""id"": 1, ""title"": ""Updated title for 1"", ""description"": ""Updated description for 1"" }, { ""id"": 2, ""description"": ""Updated description for 2"", }, { ""id"": 3, ""title"": ""Item 3"", ""description"": ""Description for 3"" } ], ""return"": true } This will return the following: { ""ok"": true, ""rows"": [ { ""id"": 1, ""title"": ""Updated title for 1"", ""description"": ""Updated description for 1"" }, { ""id"": 2, ""title"": ""Item 2"", ""description"": ""Updated description for 2"" }, { ""id"": 3, ""title"": ""Item 3"", ""description"": ""Description for 3"" } ] } When using upsert you must provide the primary key column (or columns if the table has a compound primary key) for every row, or you will get a 400 error: { ""ok"": false, ""errors"": [ ""Row 0 is missing primary key column(s): \""id\"""" ] } If your table does not have an explicit primary key you should pass the SQLite rowid key instead. Pass ""alter: true to automatically add any missing columns to the table. This requires the alter-table permission.","[""JSON API"", ""The JSON write API""]",[] metadata:database-level-metadata,metadata,database-level-metadata,Database-level metadata,"""Database-level"" metadata refers to fields that can be specified for each database in a Datasette instance. These attributes should be listed under a database inside the ""databases"" field. The following are the full list of allowed database-level metadata fields: source source_url license license_url about about_url","[""Metadata"", ""Metadata reference""]",[] metadata:id1,metadata,id1,Metadata,"Data loves metadata. Any time you run Datasette you can optionally include a YAML or JSON file with metadata about your databases and tables. Datasette will then display that information in the web UI. Run Datasette like this: datasette database1.db database2.db --metadata metadata.yaml Your metadata.yaml file can look something like this: [[[cog from metadata_doc import metadata_example metadata_example(cog, { ""title"": ""Custom title for your index page"", ""description"": ""Some description text can go here"", ""license"": ""ODbL"", ""license_url"": ""https://opendatacommons.org/licenses/odbl/"", ""source"": ""Original Data Source"", ""source_url"": ""http://example.com/"" }) ]]] [[[end]]] Choosing YAML over JSON adds support for multi-line strings and comments. The above metadata will be displayed on the index page of your Datasette-powered site. The source and license information will also be included in the footer of every page served by Datasette. Any special HTML characters in description will be escaped. If you want to include HTML in your description, you can use a description_html property instead.",[],[] metadata:id2,metadata,id2,Metadata reference,A full reference of every supported option in a metadata.json or metadata.yaml file.,"[""Metadata""]",[] metadata:label-columns,metadata,label-columns,Specifying the label column for a table,"Datasette's HTML interface attempts to display foreign key references as labelled hyperlinks. By default, it looks for referenced tables that only have two columns: a primary key column and one other. It assumes that the second column should be used as the link label. If your table has more than two columns you can specify which column should be used for the link label with the label_column property: [[[cog metadata_example(cog, { ""databases"": { ""database1"": { ""tables"": { ""example_table"": { ""label_column"": ""title"" } } } } }) ]]] [[[end]]]","[""Metadata""]",[] metadata:metadata-column-descriptions,metadata,metadata-column-descriptions,Column descriptions,"You can include descriptions for your columns by adding a ""columns"": {""name-of-column"": ""description-of-column""} block to your table metadata: [[[cog metadata_example(cog, { ""databases"": { ""database1"": { ""tables"": { ""example_table"": { ""columns"": { ""column1"": ""Description of column 1"", ""column2"": ""Description of column 2"" } } } } } }) ]]] [[[end]]] These will be displayed at the top of the table page, and will also show in the cog menu for each column. You can see an example of how these look at latest.datasette.io/fixtures/roadside_attractions .","[""Metadata""]","[{""href"": ""https://latest.datasette.io/fixtures/roadside_attractions"", ""label"": ""latest.datasette.io/fixtures/roadside_attractions""}]" metadata:metadata-default-sort,metadata,metadata-default-sort,Setting a default sort order,"By default Datasette tables are sorted by primary key. You can over-ride this default for a specific table using the ""sort"" or ""sort_desc"" metadata properties: [[[cog metadata_example(cog, { ""databases"": { ""mydatabase"": { ""tables"": { ""example_table"": { ""sort"": ""created"" } } } } }) ]]] [[[end]]] Or use ""sort_desc"" to sort in descending order: [[[cog metadata_example(cog, { ""databases"": { ""mydatabase"": { ""tables"": { ""example_table"": { ""sort_desc"": ""created"" } } } } }) ]]] [[[end]]]","[""Metadata""]",[] metadata:metadata-hiding-tables,metadata,metadata-hiding-tables,Hiding tables,"You can hide tables from the database listing view (in the same way that FTS and SpatiaLite tables are automatically hidden) using ""hidden"": true : [[[cog metadata_example(cog, { ""databases"": { ""database1"": { ""tables"": { ""example_table"": { ""hidden"": True } } } } }) ]]] [[[end]]]","[""Metadata""]",[] metadata:metadata-page-size,metadata,metadata-page-size,Setting a custom page size,"Datasette defaults to displaying 100 rows per page, for both tables and views. You can change this default page size on a per-table or per-view basis using the ""size"" key in metadata.json : [[[cog metadata_example(cog, { ""databases"": { ""mydatabase"": { ""tables"": { ""example_table"": { ""size"": 10 } } } } }) ]]] [[[end]]] This size can still be over-ridden by passing e.g. ?_size=50 in the query string.","[""Metadata""]",[] metadata:metadata-sortable-columns,metadata,metadata-sortable-columns,Setting which columns can be used for sorting,"Datasette allows any column to be used for sorting by default. If you need to control which columns are available for sorting you can do so using the optional sortable_columns key: [[[cog metadata_example(cog, { ""databases"": { ""database1"": { ""tables"": { ""example_table"": { ""sortable_columns"": [ ""height"", ""weight"" ] } } } } }) ]]] [[[end]]] This will restrict sorting of example_table to just the height and weight columns. You can also disable sorting entirely by setting ""sortable_columns"": [] You can use sortable_columns to enable specific sort orders for a view called name_of_view in the database my_database like so: [[[cog metadata_example(cog, { ""databases"": { ""my_database"": { ""tables"": { ""name_of_view"": { ""sortable_columns"": [ ""clicks"", ""impressions"" ] } } } } }) ]]] [[[end]]]","[""Metadata""]",[] metadata:metadata-source-license-about,metadata,metadata-source-license-about,"Source, license and about","The three visible metadata fields you can apply to everything, specific databases or specific tables are source, license and about. All three are optional. source and source_url should be used to indicate where the underlying data came from. license and license_url should be used to indicate the license under which the data can be used. about and about_url can be used to link to further information about the project - an accompanying blog entry for example. For each of these you can provide just the *_url field and Datasette will treat that as the default link label text and display the URL directly on the page.","[""Metadata""]",[] metadata:per-database-and-per-table-metadata,metadata,per-database-and-per-table-metadata,Per-database and per-table metadata,"Metadata at the top level of the file will be shown on the index page and in the footer on every page of the site. The license and source is expected to apply to all of your data. You can also provide metadata at the per-database or per-table level, like this: [[[cog metadata_example(cog, { ""databases"": { ""database1"": { ""source"": ""Alternative source"", ""source_url"": ""http://example.com/"", ""tables"": { ""example_table"": { ""description_html"": ""Custom table description"", ""license"": ""CC BY 3.0 US"", ""license_url"": ""https://creativecommons.org/licenses/by/3.0/us/"" } } } } }) ]]] [[[end]]] Each of the top-level metadata fields can be used at the database and table level.","[""Metadata""]",[] metadata:specifying-units-for-a-column,metadata,specifying-units-for-a-column,Specifying units for a column,"Datasette supports attaching units to a column, which will be used when displaying values from that column. SI prefixes will be used where appropriate. Column units are configured in the metadata like so: [[[cog metadata_example(cog, { ""databases"": { ""database1"": { ""tables"": { ""example_table"": { ""units"": { ""column1"": ""metres"", ""column2"": ""Hz"" } } } } } }) ]]] [[[end]]] Units are interpreted using Pint , and you can see the full list of available units in Pint's unit registry . You can also add custom units to the metadata, which will be registered with Pint: [[[cog metadata_example(cog, { ""custom_units"": [ ""decibel = [] = dB"" ] }) ]]] [[[end]]]","[""Metadata""]","[{""href"": ""https://pint.readthedocs.io/"", ""label"": ""Pint""}, {""href"": ""https://github.com/hgrecco/pint/blob/master/pint/default_en.txt"", ""label"": ""unit registry""}, {""href"": ""http://pint.readthedocs.io/en/latest/defining.html"", ""label"": ""custom units""}]" metadata:table-level-metadata,metadata,table-level-metadata,Table-level metadata,"""Table-level"" metadata refers to fields that can be specified for each table in a Datasette instance. These attributes should be listed under a specific table using the ""tables"" field. The following are the full list of allowed table-level metadata fields: source source_url license license_url about about_url hidden sort/sort_desc size sortable_columns label_column facets fts_table fts_pk searchmode columns","[""Metadata"", ""Metadata reference""]",[] metadata:top-level-metadata,metadata,top-level-metadata,Top-level metadata,"""Top-level"" metadata refers to fields that can be specified at the root level of a metadata file. These attributes are meant to describe the entire Datasette instance. The following are the full list of allowed top-level metadata fields: title description description_html license license_url source source_url","[""Metadata"", ""Metadata reference""]",[] pages:databaseview,pages,databaseview,Database,"Each database has a page listing the tables, views and canned queries available for that database. If the execute-sql permission is enabled (it's on by default) there will also be an interface for executing arbitrary SQL select queries against the data. Examples: fivethirtyeight.datasettes.com/fivethirtyeight global-power-plants.datasettes.com/global-power-plants The JSON version of this page provides programmatic access to the underlying data: fivethirtyeight.datasettes.com/fivethirtyeight.json global-power-plants.datasettes.com/global-power-plants.json","[""Pages and API endpoints""]","[{""href"": ""https://fivethirtyeight.datasettes.com/fivethirtyeight"", ""label"": ""fivethirtyeight.datasettes.com/fivethirtyeight""}, {""href"": ""https://global-power-plants.datasettes.com/global-power-plants"", ""label"": ""global-power-plants.datasettes.com/global-power-plants""}, {""href"": ""https://fivethirtyeight.datasettes.com/fivethirtyeight.json"", ""label"": ""fivethirtyeight.datasettes.com/fivethirtyeight.json""}, {""href"": ""https://global-power-plants.datasettes.com/global-power-plants.json"", ""label"": ""global-power-plants.datasettes.com/global-power-plants.json""}]" pages:databaseview-hidden,pages,databaseview-hidden,Hidden tables,"Some tables listed on the database page are treated as hidden. Hidden tables are not completely invisible - they can be accessed through the ""hidden tables"" link at the bottom of the page. They are hidden because they represent low-level implementation details which are generally not useful to end-users of Datasette. The following tables are hidden by default: Any table with a name that starts with an underscore - this is a Datasette convention to help plugins easily hide their own internal tables. Tables that have been configured as ""hidden"": true using Hiding tables . *_fts tables that implement SQLite full-text search indexes. Tables relating to the inner workings of the SpatiaLite SQLite extension. sqlite_stat tables used to store statistics used by the query optimizer.","[""Pages and API endpoints"", ""Database""]",[] pages:indexview,pages,indexview,Top-level index,"The root page of any Datasette installation is an index page that lists all of the currently attached databases. Some examples: fivethirtyeight.datasettes.com global-power-plants.datasettes.com register-of-members-interests.datasettes.com Add /.json to the end of the URL for the JSON version of the underlying data: fivethirtyeight.datasettes.com/.json global-power-plants.datasettes.com/.json register-of-members-interests.datasettes.com/.json","[""Pages and API endpoints""]","[{""href"": ""https://fivethirtyeight.datasettes.com/"", ""label"": ""fivethirtyeight.datasettes.com""}, {""href"": ""https://global-power-plants.datasettes.com/"", ""label"": ""global-power-plants.datasettes.com""}, {""href"": ""https://register-of-members-interests.datasettes.com/"", ""label"": ""register-of-members-interests.datasettes.com""}, {""href"": ""https://fivethirtyeight.datasettes.com/.json"", ""label"": ""fivethirtyeight.datasettes.com/.json""}, {""href"": ""https://global-power-plants.datasettes.com/.json"", ""label"": ""global-power-plants.datasettes.com/.json""}, {""href"": ""https://register-of-members-interests.datasettes.com/.json"", ""label"": ""register-of-members-interests.datasettes.com/.json""}]" pages:pages,pages,pages,Pages and API endpoints,"The Datasette web application offers a number of different pages that can be accessed to explore the data in question, each of which is accompanied by an equivalent JSON API.",[],[] pages:rowview,pages,rowview,Row,"Every row in every Datasette table has its own URL. This means individual records can be linked to directly. Table cells with extremely long text contents are truncated on the table view according to the truncate_cells_html setting. If a cell has been truncated the full length version of that cell will be available on the row page. Rows which are the targets of foreign key references from other tables will show a link to a filtered search for all records that reference that row. Here's an example from the Registers of Members Interests database: ../people/uk~2Eorg~2Epublicwhip~2Fperson~2F10001 Note that this URL includes the encoded primary key of the record. Here's that same page as JSON: ../people/uk~2Eorg~2Epublicwhip~2Fperson~2F10001.json","[""Pages and API endpoints""]","[{""href"": ""https://register-of-members-interests.datasettes.com/regmem/people/uk~2Eorg~2Epublicwhip~2Fperson~2F10001"", ""label"": ""../people/uk~2Eorg~2Epublicwhip~2Fperson~2F10001""}, {""href"": ""https://register-of-members-interests.datasettes.com/regmem/people/uk~2Eorg~2Epublicwhip~2Fperson~2F10001.json"", ""label"": ""../people/uk~2Eorg~2Epublicwhip~2Fperson~2F10001.json""}]" pages:tableview,pages,tableview,Table,"The table page is the heart of Datasette: it allows users to interactively explore the contents of a database table, including sorting, filtering, Full-text search and applying Facets . The HTML interface is worth spending some time exploring. As with other pages, you can return the JSON data by appending .json to the URL path, before any ? query string arguments. The query string arguments are described in more detail here: Table arguments You can also use the table page to interactively construct a SQL query - by applying different filters and a sort order for example - and then click the ""View and edit SQL"" link to see the SQL query that was used for the page and edit and re-submit it. Some examples: ../items lists all of the line-items registered by UK MPs as potential conflicts of interest. It demonstrates Datasette's support for Full-text search . ../antiquities-act%2Factions_under_antiquities_act is an interface for exploring the ""actions under the antiquities act"" data table published by FiveThirtyEight. ../global-power-plants?country_long=United+Kingdom&primary_fuel=Gas is a filtered table page showing every Gas power plant in the United Kingdom. It includes some default facets (configured using its metadata.json ) and uses the datasette-cluster-map plugin to show a map of the results.","[""Pages and API endpoints""]","[{""href"": ""https://register-of-members-interests.datasettes.com/regmem/items"", ""label"": ""../items""}, {""href"": ""https://fivethirtyeight.datasettes.com/fivethirtyeight/antiquities-act%2Factions_under_antiquities_act"", ""label"": ""../antiquities-act%2Factions_under_antiquities_act""}, {""href"": ""https://global-power-plants.datasettes.com/global-power-plants/global-power-plants?_facet=primary_fuel&_facet=owner&_facet=country_long&country_long__exact=United+Kingdom&primary_fuel=Gas"", ""label"": ""../global-power-plants?country_long=United+Kingdom&primary_fuel=Gas""}, {""href"": ""https://global-power-plants.datasettes.com/-/metadata"", ""label"": ""its metadata.json""}, {""href"": ""https://github.com/simonw/datasette-cluster-map"", ""label"": ""datasette-cluster-map""}]" performance:http-caching,performance,http-caching,HTTP caching,"If your database is immutable and guaranteed not to change, you can gain major performance improvements from Datasette by enabling HTTP caching. This can work at two different levels. First, it can tell browsers to cache the results of queries and serve future requests from the browser cache. More significantly, it allows you to run Datasette behind a caching proxy such as Varnish or use a cache provided by a hosted service such as Fastly or Cloudflare . This can provide incredible speed-ups since a query only needs to be executed by Datasette the first time it is accessed - all subsequent hits can then be served by the cache. Using a caching proxy in this way could enable a Datasette-backed visualization to serve thousands of hits a second while running Datasette itself on extremely inexpensive hosting. Datasette's integration with HTTP caches can be enabled using a combination of configuration options and query string arguments. The default_cache_ttl setting sets the default HTTP cache TTL for all Datasette pages. This is 5 seconds unless you change it - you can set it to 0 if you wish to disable HTTP caching entirely. You can also change the cache timeout on a per-request basis using the ?_ttl=10 query string parameter. This can be useful when you are working with the Datasette JSON API - you may decide that a specific query can be cached for a longer time, or maybe you need to set ?_ttl=0 for some requests for example if you are running a SQL order by random() query.","[""Performance and caching""]","[{""href"": ""https://varnish-cache.org/"", ""label"": ""Varnish""}, {""href"": ""https://www.fastly.com/"", ""label"": ""Fastly""}, {""href"": ""https://www.cloudflare.com/"", ""label"": ""Cloudflare""}]" performance:performance,performance,performance,Performance and caching,"Datasette runs on top of SQLite, and SQLite has excellent performance. For small databases almost any query should return in just a few milliseconds, and larger databases (100s of MBs or even GBs of data) should perform extremely well provided your queries make sensible use of database indexes. That said, there are a number of tricks you can use to improve Datasette's performance.",[],[] performance:performance-hashed-urls,performance,performance-hashed-urls,datasette-hashed-urls,"If you open a database file in immutable mode using the -i option, you can be assured that the content of that database will not change for the lifetime of the Datasette server. The datasette-hashed-urls plugin implements an optimization where your database is served with part of the SHA-256 hash of the database contents baked into the URL. A database at /fixtures will instead be served at /fixtures-aa7318b , and a year-long cache expiry header will be returned with those pages. This will then be cached by both browsers and caching proxies such as Cloudflare or Fastly, providing a potentially significant performance boost. To install the plugin, run the following: datasette install datasette-hashed-urls Prior to Datasette 0.61 hashed URL mode was a core Datasette feature, enabled using the hash_urls setting. This implementation has now been removed in favor of the datasette-hashed-urls plugin. Prior to Datasette 0.28 hashed URL mode was the default behaviour for Datasette, since all database files were assumed to be immutable and unchanging. From 0.28 onwards the default has been to treat database files as mutable unless explicitly configured otherwise.","[""Performance and caching""]","[{""href"": ""https://datasette.io/plugins/datasette-hashed-urls"", ""label"": ""datasette-hashed-urls plugin""}]" performance:performance-immutable-mode,performance,performance-immutable-mode,Immutable mode,"If you can be certain that a SQLite database file will not be changed by another process you can tell Datasette to open that file in immutable mode . Doing so will disable all locking and change detection, which can result in improved query performance. This also enables further optimizations relating to HTTP caching, described below. To open a file in immutable mode pass it to the datasette command using the -i option: datasette -i data.db When you open a file in immutable mode like this Datasette will also calculate and cache the row counts for each table in that database when it first starts up, further improving performance.","[""Performance and caching""]",[] performance:performance-inspect,performance,performance-inspect,"Using ""datasette inspect""","Counting the rows in a table can be a very expensive operation on larger databases. In immutable mode Datasette performs this count only once and caches the results, but this can still cause server startup time to increase by several seconds or more. If you know that a database is never going to change you can precalculate the table row counts once and store then in a JSON file, then use that file when you later start the server. To create a JSON file containing the calculated row counts for a database, use the following: datasette inspect data.db --inspect-file=counts.json Then later you can start Datasette against the counts.json file and use it to skip the row counting step and speed up server startup: datasette -i data.db --inspect-file=counts.json You need to use the -i immutable mode against the database file here or the counts from the JSON file will be ignored. You will rarely need to use this optimization in every-day use, but several of the datasette publish commands described in Publishing data use this optimization for better performance when deploying a database file to a hosting provider.","[""Performance and caching""]",[] plugin_hooks:id1,plugin_hooks,id1,Plugin hooks,"Datasette plugins use plugin hooks to customize Datasette's behavior. These hooks are powered by the pluggy plugin system. Each plugin can implement one or more hooks using the @hookimpl decorator against a function named that matches one of the hooks documented on this page. When you implement a plugin hook you can accept any or all of the parameters that are documented as being passed to that hook. For example, you can implement the render_cell plugin hook like this even though the full documented hook signature is render_cell(row, value, column, table, database, datasette) : @hookimpl def render_cell(value, column): if column == ""stars"": return ""*"" * int(value) List of plugin hooks prepare_connection(conn, database, datasette) prepare_jinja2_environment(env, datasette) Page extras extra_template_vars(template, database, table, columns, view_name, request, datasette) extra_css_urls(template, database, table, columns, view_name, request, datasette) extra_js_urls(template, database, table, columns, view_name, request, datasette) extra_body_script(template, database, table, columns, view_name, request, datasette) publish_subcommand(publish) render_cell(row, value, column, table, database, datasette, request) register_output_renderer(datasette) register_routes(datasette) register_commands(cli) register_facet_classes() register_permissions(datasette) asgi_wrapper(datasette) startup(datasette) canned_queries(datasette, database, actor) actor_from_request(datasette, request) actors_from_ids(datasette, actor_ids) jinja2_environment_from_request(datasette, request, env) filters_from_request(request, database, table, datasette) permission_allowed(datasette, actor, action, resource) register_magic_parameters(datasette) forbidden(datasette, request, message) handle_exception(datasette, request, exception) skip_csrf(datasette, scope) get_metadata(datasette, key, database, table) menu_links(datasette, actor, request) Action hooks table_actions(datasette, actor, database, table, request) view_actions(datasette, actor, database, view, request) query_actions(datasette, actor, database, query_name, request, sql, params) row_actions(datasette, actor, request, database, table, row) database_actions(datasette, actor, database, request) homepage_actions(datasette, actor, request) Template slots top_homepage(datasette, request) top_database(datasette, request, database) top_table(datasette, request, database, table) top_row(datasette, request, database, table, row) top_query(datasette, request, database, sql) top_canned_query(datasette, request, database, query_name) Event tracking track_event(datasette, event) register_events(datasette)",[],"[{""href"": ""https://pluggy.readthedocs.io/"", ""label"": ""pluggy""}]" plugin_hooks:plugin-actions,plugin_hooks,plugin-actions,Action hooks,"Action hooks can be used to add items to the action menus that appear at the top of different pages within Datasette. Unlike menu_links() , actions which are displayed on every page, actions should only be relevant to the page the user is currently viewing. Each of these hooks should return return a list of {""href"": ""..."", ""label"": ""...""} menu items, with optional ""description"": ""..."" keys describing each action in more detail. They can alternatively return an async def awaitable function which, when called, returns a list of those menu items.","[""Plugin hooks""]",[] plugin_hooks:plugin-asgi-wrapper,plugin_hooks,plugin-asgi-wrapper,asgi_wrapper(datasette),"Return an ASGI middleware wrapper function that will be applied to the Datasette ASGI application. This is a very powerful hook. You can use it to manipulate the entire Datasette response, or even to configure new URL routes that will be handled by your own custom code. You can write your ASGI code directly against the low-level specification, or you can use the middleware utilities provided by an ASGI framework such as Starlette . This example plugin adds a x-databases HTTP header listing the currently attached databases: from datasette import hookimpl from functools import wraps @hookimpl def asgi_wrapper(datasette): def wrap_with_databases_header(app): @wraps(app) async def add_x_databases_header( scope, receive, send ): async def wrapped_send(event): if event[""type""] == ""http.response.start"": original_headers = ( event.get(""headers"") or [] ) event = { ""type"": event[""type""], ""status"": event[""status""], ""headers"": original_headers + [ [ b""x-databases"", "", "".join( datasette.databases.keys() ).encode(""utf-8""), ] ], } await send(event) await app(scope, receive, wrapped_send) return add_x_databases_header return wrap_with_databases_header Examples: datasette-cors , datasette-pyinstrument , datasette-total-page-time","[""Plugin hooks""]","[{""href"": ""https://asgi.readthedocs.io/"", ""label"": ""ASGI""}, {""href"": ""https://www.starlette.io/middleware/"", ""label"": ""Starlette""}, {""href"": ""https://datasette.io/plugins/datasette-cors"", ""label"": ""datasette-cors""}, {""href"": ""https://datasette.io/plugins/datasette-pyinstrument"", ""label"": ""datasette-pyinstrument""}, {""href"": ""https://datasette.io/plugins/datasette-total-page-time"", ""label"": ""datasette-total-page-time""}]" plugin_hooks:plugin-event-tracking,plugin_hooks,plugin-event-tracking,Event tracking,"Datasette includes an internal mechanism for tracking notable events. This can be used for analytics, but can also be used by plugins that want to listen out for when key events occur (such as a table being created) and take action in response. Plugins can register to receive events using the track_event plugin hook. They can also define their own events for other plugins to receive using the register_events() plugin hook , combined with calls to the datasette.track_event() internal method .","[""Plugin hooks""]",[] plugin_hooks:plugin-hook-actor-from-request,plugin_hooks,plugin-hook-actor-from-request,"actor_from_request(datasette, request)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. request - Request object The current HTTP request. This is part of Datasette's authentication and permissions system . The function should attempt to authenticate an actor (either a user or an API actor of some sort) based on information in the request. If it cannot authenticate an actor, it should return None . Otherwise it should return a dictionary representing that actor. Here's an example that authenticates the actor based on an incoming API key: from datasette import hookimpl import secrets SECRET_KEY = ""this-is-a-secret"" @hookimpl def actor_from_request(datasette, request): authorization = ( request.headers.get(""authorization"") or """" ) expected = ""Bearer {}"".format(SECRET_KEY) if secrets.compare_digest(authorization, expected): return {""id"": ""bot""} If you install this in your plugins directory you can test it like this: curl -H 'Authorization: Bearer this-is-a-secret' http://localhost:8003/-/actor.json Instead of returning a dictionary, this function can return an awaitable function which itself returns either None or a dictionary. This is useful for authentication functions that need to make a database query - for example: from datasette import hookimpl @hookimpl def actor_from_request(datasette, request): async def inner(): token = request.args.get(""_token"") if not token: return None # Look up ?_token=xxx in sessions table result = await datasette.get_database().execute( ""select count(*) from sessions where token = ?"", [token], ) if result.first()[0]: return {""token"": token} else: return None return inner Examples: datasette-auth-tokens , datasette-auth-passwords","[""Plugin hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-auth-tokens"", ""label"": ""datasette-auth-tokens""}, {""href"": ""https://datasette.io/plugins/datasette-auth-passwords"", ""label"": ""datasette-auth-passwords""}]" plugin_hooks:plugin-hook-actors-from-ids,plugin_hooks,plugin-hook-actors-from-ids,"actors_from_ids(datasette, actor_ids)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. actor_ids - list of strings or integers The actor IDs to look up. The hook must return a dictionary that maps the incoming actor IDs to their full dictionary representation. Some plugins that implement social features may store the ID of the actor that performed an action - added a comment, bookmarked a table or similar - and then need a way to resolve those IDs into display-friendly actor dictionaries later on. The await datasette.actors_from_ids(actor_ids) internal method can be used to look up actors from their IDs. It will dispatch to the first plugin that implements this hook. Unlike other plugin hooks, this only uses the first implementation of the hook to return a result. You can expect users to only have a single plugin installed that implements this hook. If no plugin is installed, Datasette defaults to returning actors that are just {""id"": actor_id} . The hook can return a dictionary or an awaitable function that then returns a dictionary. This example implementation returns actors from a database table: from datasette import hookimpl @hookimpl def actors_from_ids(datasette, actor_ids): db = datasette.get_database(""actors"") async def inner(): sql = ""select id, name from actors where id in ({})"".format( "", "".join(""?"" for _ in actor_ids) ) actors = {} for row in (await db.execute(sql, actor_ids)).rows: actor = dict(row) actors[actor[""id""]] = actor return actors return inner The returned dictionary from this example looks like this: { ""1"": {""id"": ""1"", ""name"": ""Tony""}, ""2"": {""id"": ""2"", ""name"": ""Tina""}, } These IDs could be integers or strings, depending on how the actors used by the Datasette instance are configured. Example: datasette-remote-actors","[""Plugin hooks""]","[{""href"": ""https://github.com/datasette/datasette-remote-actors"", ""label"": ""datasette-remote-actors""}]" plugin_hooks:plugin-hook-canned-queries,plugin_hooks,plugin-hook-canned-queries,"canned_queries(datasette, database, actor)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. database - string The name of the database. actor - dictionary or None The currently authenticated actor . Use this hook to return a dictionary of additional canned query definitions for the specified database. The return value should be the same shape as the JSON described in the canned query documentation. from datasette import hookimpl @hookimpl def canned_queries(datasette, database): if database == ""mydb"": return { ""my_query"": { ""sql"": ""select * from my_table where id > :min_id"" } } The hook can alternatively return an awaitable function that returns a list. Here's an example that returns queries that have been stored in the saved_queries database table, if one exists: from datasette import hookimpl @hookimpl def canned_queries(datasette, database): async def inner(): db = datasette.get_database(database) if await db.table_exists(""saved_queries""): results = await db.execute( ""select name, sql from saved_queries"" ) return { result[""name""]: {""sql"": result[""sql""]} for result in results } return inner The actor parameter can be used to include the currently authenticated actor in your decision. Here's an example that returns saved queries that were saved by that actor: from datasette import hookimpl @hookimpl def canned_queries(datasette, database, actor): async def inner(): db = datasette.get_database(database) if actor is not None and await db.table_exists( ""saved_queries"" ): results = await db.execute( ""select name, sql from saved_queries where actor_id = :id"", {""id"": actor[""id""]}, ) return { result[""name""]: {""sql"": result[""sql""]} for result in results } return inner Example: datasette-saved-queries","[""Plugin hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-saved-queries"", ""label"": ""datasette-saved-queries""}]" plugin_hooks:plugin-hook-database-actions,plugin_hooks,plugin-hook-database-actions,"database_actions(datasette, actor, database, request)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. actor - dictionary or None The currently authenticated actor . database - string The name of the database. request - Request object The current HTTP request. Populates an actions menu on the database page. This example adds a new database action for creating a table, if the user has the edit-schema permission: from datasette import hookimpl @hookimpl def database_actions(datasette, actor, database): async def inner(): if not await datasette.permission_allowed( actor, ""edit-schema"", resource=database, default=False, ): return [] return [ { ""href"": datasette.urls.path( ""/-/edit-schema/{}/-/create"".format( database ) ), ""label"": ""Create a table"", } ] return inner Example: datasette-graphql , datasette-edit-schema","[""Plugin hooks"", ""Action hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-graphql"", ""label"": ""datasette-graphql""}, {""href"": ""https://datasette.io/plugins/datasette-edit-schema"", ""label"": ""datasette-edit-schema""}]" plugin_hooks:plugin-hook-extra-body-script,plugin_hooks,plugin-hook-extra-body-script,"extra_body_script(template, database, table, columns, view_name, request, datasette)","Extra JavaScript to be added to a element: @hookimpl def extra_body_script(): return { ""module"": True, ""script"": ""console.log('Your JavaScript goes here...')"", } This will add the following to the end of your page: Example: datasette-cluster-map","[""Plugin hooks"", ""Page extras""]","[{""href"": ""https://datasette.io/plugins/datasette-cluster-map"", ""label"": ""datasette-cluster-map""}]" plugin_hooks:plugin-hook-extra-css-urls,plugin_hooks,plugin-hook-extra-css-urls,"extra_css_urls(template, database, table, columns, view_name, request, datasette)","This takes the same arguments as extra_template_vars(...) Return a list of extra CSS URLs that should be included on the page. These can take advantage of the CSS class hooks described in Custom pages and templates . This can be a list of URLs: from datasette import hookimpl @hookimpl def extra_css_urls(): return [ ""https://stackpath.bootstrapcdn.com/bootstrap/4.1.0/css/bootstrap.min.css"" ] Or a list of dictionaries defining both a URL and an SRI hash : @hookimpl def extra_css_urls(): return [ { ""url"": ""https://stackpath.bootstrapcdn.com/bootstrap/4.1.0/css/bootstrap.min.css"", ""sri"": ""sha384-9gVQ4dYFwwWSjIDZnLEWnxCjeSWFphJiwGPXr1jddIhOegiu1FwO5qRGvFXOdJZ4"", } ] This function can also return an awaitable function, useful if it needs to run any async code: @hookimpl def extra_css_urls(datasette): async def inner(): db = datasette.get_database() results = await db.execute( ""select url from css_files"" ) return [r[0] for r in results] return inner Examples: datasette-cluster-map , datasette-vega","[""Plugin hooks"", ""Page extras""]","[{""href"": ""https://www.srihash.org/"", ""label"": ""SRI hash""}, {""href"": ""https://datasette.io/plugins/datasette-cluster-map"", ""label"": ""datasette-cluster-map""}, {""href"": ""https://datasette.io/plugins/datasette-vega"", ""label"": ""datasette-vega""}]" plugin_hooks:plugin-hook-extra-js-urls,plugin_hooks,plugin-hook-extra-js-urls,"extra_js_urls(template, database, table, columns, view_name, request, datasette)","This takes the same arguments as extra_template_vars(...) This works in the same way as extra_css_urls() but for JavaScript. You can return a list of URLs, a list of dictionaries or an awaitable function that returns those things: from datasette import hookimpl @hookimpl def extra_js_urls(): return [ { ""url"": ""https://code.jquery.com/jquery-3.3.1.slim.min.js"", ""sri"": ""sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo"", } ] You can also return URLs to files from your plugin's static/ directory, if you have one: @hookimpl def extra_js_urls(): return [""/-/static-plugins/your-plugin/app.js""] Note that your-plugin here should be the hyphenated plugin name - the name that is displayed in the list on the /-/plugins debug page. If your code uses JavaScript modules you should include the ""module"": True key. See Custom CSS and JavaScript for more details. @hookimpl def extra_js_urls(): return [ { ""url"": ""/-/static-plugins/your-plugin/app.js"", ""module"": True, } ] Examples: datasette-cluster-map , datasette-vega","[""Plugin hooks"", ""Page extras""]","[{""href"": ""https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules"", ""label"": ""JavaScript modules""}, {""href"": ""https://datasette.io/plugins/datasette-cluster-map"", ""label"": ""datasette-cluster-map""}, {""href"": ""https://datasette.io/plugins/datasette-vega"", ""label"": ""datasette-vega""}]" plugin_hooks:plugin-hook-extra-template-vars,plugin_hooks,plugin-hook-extra-template-vars,"extra_template_vars(template, database, table, columns, view_name, request, datasette)","Extra template variables that should be made available in the rendered template context. template - string The template that is being rendered, e.g. database.html database - string or None The name of the database, or None if the page does not correspond to a database (e.g. the root page) table - string or None The name of the table, or None if the page does not correct to a table columns - list of strings or None The names of the database columns that will be displayed on this page. None if the page does not contain a table. view_name - string The name of the view being displayed. ( index , database , table , and row are the most important ones.) request - Request object or None The current HTTP request. This can be None if the request object is not available. datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) This hook can return one of three different types: Dictionary If you return a dictionary its keys and values will be merged into the template context. Function that returns a dictionary If you return a function it will be executed. If it returns a dictionary those values will will be merged into the template context. Function that returns an awaitable function that returns a dictionary You can also return a function which returns an awaitable function which returns a dictionary. Datasette runs Jinja2 in async mode , which means you can add awaitable functions to the template scope and they will be automatically awaited when they are rendered by the template. Here's an example plugin that adds a ""user_agent"" variable to the template context containing the current request's User-Agent header: @hookimpl def extra_template_vars(request): return {""user_agent"": request.headers.get(""user-agent"")} This example returns an awaitable function which adds a list of hidden_table_names to the context: @hookimpl def extra_template_vars(datasette, database): async def hidden_table_names(): if database: db = datasette.databases[database] return { ""hidden_table_names"": await db.hidden_table_names() } else: return {} return hidden_table_names And here's an example which adds a sql_first(sql_query) function which executes a SQL statement and returns the first column of the first row of results: @hookimpl def extra_template_vars(datasette, database): async def sql_first(sql, dbname=None): dbname = ( dbname or database or next(iter(datasette.databases.keys())) ) result = await datasette.execute(dbname, sql) return result.rows[0][0] return {""sql_first"": sql_first} You can then use the new function in a template like so: SQLite version: {{ sql_first(""select sqlite_version()"") }} Examples: datasette-search-all , datasette-template-sql","[""Plugin hooks"", ""Page extras""]","[{""href"": ""https://jinja.palletsprojects.com/en/2.10.x/api/#async-support"", ""label"": ""async mode""}, {""href"": ""https://datasette.io/plugins/datasette-search-all"", ""label"": ""datasette-search-all""}, {""href"": ""https://datasette.io/plugins/datasette-template-sql"", ""label"": ""datasette-template-sql""}]" plugin_hooks:plugin-hook-filters-from-request,plugin_hooks,plugin-hook-filters-from-request,"filters_from_request(request, database, table, datasette)","request - Request object The current HTTP request. database - string The name of the database. table - string The name of the table. datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. This hook runs on the table page, and can influence the where clause of the SQL query used to populate that page, based on query string arguments on the incoming request. The hook should return an instance of datasette.filters.FilterArguments which has one required and three optional arguments: return FilterArguments( where_clauses=[""id > :max_id""], params={""max_id"": 5}, human_descriptions=[""max_id is greater than 5""], extra_context={}, ) The arguments to the FilterArguments class constructor are as follows: where_clauses - list of strings, required A list of SQL fragments that will be inserted into the SQL query, joined by the and operator. These can include :named parameters which will be populated using data in params . params - dictionary, optional Additional keyword arguments to be used when the query is executed. These should match any :arguments in the where clauses. human_descriptions - list of strings, optional These strings will be included in the human-readable description at the top of the page and the page . extra_context - dictionary, optional Additional context variables that should be made available to the table.html template when it is rendered. This example plugin causes 0 results to be returned if ?_nothing=1 is added to the URL: from datasette import hookimpl from datasette.filters import FilterArguments @hookimpl def filters_from_request(self, request): if request.args.get(""_nothing""): return FilterArguments( [""1 = 0""], human_descriptions=[""NOTHING""] ) Example: datasette-leaflet-freedraw","[""Plugin hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-leaflet-freedraw"", ""label"": ""datasette-leaflet-freedraw""}]" plugin_hooks:plugin-hook-forbidden,plugin_hooks,plugin-hook-forbidden,"forbidden(datasette, request, message)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to render templates or execute SQL queries. request - Request object The current HTTP request. message - string A message hinting at why the request was forbidden. Plugins can use this to customize how Datasette responds when a 403 Forbidden error occurs - usually because a page failed a permission check, see Permissions . If a plugin hook wishes to react to the error, it should return a Response object . This example returns a redirect to a /-/login page: from datasette import hookimpl from urllib.parse import urlencode @hookimpl def forbidden(request, message): return Response.redirect( ""/-/login?="" + urlencode({""message"": message}) ) The function can alternatively return an awaitable function if it needs to make any asynchronous method calls. This example renders a template: from datasette import hookimpl, Response @hookimpl def forbidden(datasette): async def inner(): return Response.html( await datasette.render_template( ""render_message.html"", request=request ) ) return inner","[""Plugin hooks""]",[] plugin_hooks:plugin-hook-get-metadata,plugin_hooks,plugin-hook-get-metadata,"get_metadata(datasette, key, database, table)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) . actor - dictionary or None The currently authenticated actor . database - string or None The name of the database metadata is being asked for. table - string or None The name of the table. key - string or None The name of the key for which data is being asked for. This hook is responsible for returning a dictionary corresponding to Datasette Metadata . This function is passed the database , table and key which were passed to the upstream internal request for metadata. Regardless, it is important to return a global metadata object, where ""databases"": [] would be a top-level key. The dictionary returned here, will be merged with, and overwritten by, the contents of the physical metadata.yaml if one is present. The design of this plugin hook does not currently provide a mechanism for interacting with async code, and may change in the future. See issue 1384 . @hookimpl def get_metadata(datasette, key, database, table): metadata = { ""title"": ""This will be the Datasette landing page title!"", ""description"": get_instance_description(datasette), ""databases"": [], } for db_name, db_data_dict in get_my_database_meta( datasette, database, table, key ): metadata[""databases""][db_name] = db_data_dict # whatever we return here will be merged with any other plugins using this hook and # will be overwritten by a local metadata.yaml if one exists! return metadata Example: datasette-remote-metadata plugin","[""Plugin hooks""]","[{""href"": ""https://github.com/simonw/datasette/issues/1384"", ""label"": ""issue 1384""}, {""href"": ""https://datasette.io/plugins/datasette-remote-metadata"", ""label"": ""datasette-remote-metadata plugin""}]" plugin_hooks:plugin-hook-handle-exception,plugin_hooks,plugin-hook-handle-exception,"handle_exception(datasette, request, exception)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to render templates or execute SQL queries. request - Request object The current HTTP request. exception - Exception The exception that was raised. This hook is called any time an unexpected exception is raised. You can use it to record the exception. If your handler returns a Response object it will be returned to the client in place of the default Datasette error page. The handler can return a response directly, or it can return return an awaitable function that returns a response. This example logs an error to Sentry and then renders a custom error page: from datasette import hookimpl, Response import sentry_sdk @hookimpl def handle_exception(datasette, exception): sentry_sdk.capture_exception(exception) async def inner(): return Response.html( await datasette.render_template( ""custom_error.html"", request=request ) ) return inner Example: datasette-sentry","[""Plugin hooks""]","[{""href"": ""https://sentry.io/"", ""label"": ""Sentry""}, {""href"": ""https://datasette.io/plugins/datasette-sentry"", ""label"": ""datasette-sentry""}]" plugin_hooks:plugin-hook-homepage-actions,plugin_hooks,plugin-hook-homepage-actions,"homepage_actions(datasette, actor, request)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. actor - dictionary or None The currently authenticated actor . request - Request object The current HTTP request. Populates an actions menu on the top-level index homepage of the Datasette instance. This example adds a link an imagined tool for editing the homepage, only for signed in users: from datasette import hookimpl @hookimpl def homepage_actions(datasette, actor): if actor: return [ { ""href"": datasette.urls.path( ""/-/customize-homepage"" ), ""label"": ""Customize homepage"", } ]","[""Plugin hooks"", ""Action hooks""]",[] plugin_hooks:plugin-hook-jinja2-environment-from-request,plugin_hooks,plugin-hook-jinja2-environment-from-request,"jinja2_environment_from_request(datasette, request, env)","datasette - Datasette class A Datasette instance. request - Request object or None The current HTTP request, if one is available. env - Environment The Jinja2 environment that will be used to render the current page. This hook can be used to return a customized Jinja environment based on the incoming request. If you want to run a single Datasette instance that serves different content for different domains, you can do so like this: from datasette import hookimpl from jinja2 import ChoiceLoader, FileSystemLoader @hookimpl def jinja2_environment_from_request(request, env): if request and request.host == ""www.niche-museums.com"": return env.overlay( loader=ChoiceLoader( [ FileSystemLoader( ""/mnt/niche-museums/templates"" ), env.loader, ] ), enable_async=True, ) return env This uses the Jinja overlay() method to create a new environment identical to the default environment except for having a different template loader, which first looks in the /mnt/niche-museums/templates directory before falling back on the default loader.","[""Plugin hooks""]","[{""href"": ""https://jinja.palletsprojects.com/en/3.0.x/api/#jinja2.Environment"", ""label"": ""Jinja environment""}, {""href"": ""https://jinja.palletsprojects.com/en/3.0.x/api/#jinja2.Environment.overlay"", ""label"": ""overlay() method""}]" plugin_hooks:plugin-hook-menu-links,plugin_hooks,plugin-hook-menu-links,"menu_links(datasette, actor, request)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. actor - dictionary or None The currently authenticated actor . request - Request object or None The current HTTP request. This can be None if the request object is not available. This hook allows additional items to be included in the menu displayed by Datasette's top right menu icon. The hook should return a list of {""href"": ""..."", ""label"": ""...""} menu items. These will be added to the menu. It can alternatively return an async def awaitable function which returns a list of menu items. This example adds a new menu item but only if the signed in user is ""root"" : from datasette import hookimpl @hookimpl def menu_links(datasette, actor): if actor and actor.get(""id"") == ""root"": return [ { ""href"": datasette.urls.path( ""/-/edit-schema"" ), ""label"": ""Edit schema"", }, ] Using datasette.urls here ensures that links in the menu will take the base_url setting into account. Examples: datasette-search-all , datasette-graphql","[""Plugin hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-search-all"", ""label"": ""datasette-search-all""}, {""href"": ""https://datasette.io/plugins/datasette-graphql"", ""label"": ""datasette-graphql""}]" plugin_hooks:plugin-hook-permission-allowed,plugin_hooks,plugin-hook-permission-allowed,"permission_allowed(datasette, actor, action, resource)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. actor - dictionary The current actor, as decided by actor_from_request(datasette, request) . action - string The action to be performed, e.g. ""edit-table"" . resource - string or None An identifier for the individual resource, e.g. the name of the table. Called to check that an actor has permission to perform an action on a resource. Can return True if the action is allowed, False if the action is not allowed or None if the plugin does not have an opinion one way or the other. Here's an example plugin which randomly selects if a permission should be allowed or denied, except for view-instance which always uses the default permission scheme instead. from datasette import hookimpl import random @hookimpl def permission_allowed(action): if action != ""view-instance"": # Return True or False at random return random.random() > 0.5 # Returning None falls back to default permissions This function can alternatively return an awaitable function which itself returns True , False or None . You can use this option if you need to execute additional database queries using await datasette.execute(...) . Here's an example that allows users to view the admin_log table only if their actor id is present in the admin_users table. It aso disallows arbitrary SQL queries for the staff.db database for all users. @hookimpl def permission_allowed(datasette, actor, action, resource): async def inner(): if action == ""execute-sql"" and resource == ""staff"": return False if action == ""view-table"" and resource == ( ""staff"", ""admin_log"", ): if not actor: return False user_id = actor[""id""] return await datasette.get_database( ""staff"" ).execute( ""select count(*) from admin_users where user_id = :user_id"", {""user_id"": user_id}, ) return inner See built-in permissions for a full list of permissions that are included in Datasette core. Example: datasette-permissions-sql","[""Plugin hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-permissions-sql"", ""label"": ""datasette-permissions-sql""}]" plugin_hooks:plugin-hook-prepare-connection,plugin_hooks,plugin-hook-prepare-connection,"prepare_connection(conn, database, datasette)","conn - sqlite3 connection object The connection that is being opened database - string The name of the database datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) This hook is called when a new SQLite database connection is created. You can use it to register custom SQL functions , aggregates and collations. For example: from datasette import hookimpl import random @hookimpl def prepare_connection(conn): conn.create_function( ""random_integer"", 2, random.randint ) This registers a SQL function called random_integer which takes two arguments and can be called like this: select random_integer(1, 10); Examples: datasette-jellyfish , datasette-jq , datasette-haversine , datasette-rure","[""Plugin hooks""]","[{""href"": ""https://docs.python.org/2/library/sqlite3.html#sqlite3.Connection.create_function"", ""label"": ""register custom SQL functions""}, {""href"": ""https://datasette.io/plugins/datasette-jellyfish"", ""label"": ""datasette-jellyfish""}, {""href"": ""https://datasette.io/plugins/datasette-jq"", ""label"": ""datasette-jq""}, {""href"": ""https://datasette.io/plugins/datasette-haversine"", ""label"": ""datasette-haversine""}, {""href"": ""https://datasette.io/plugins/datasette-rure"", ""label"": ""datasette-rure""}]" plugin_hooks:plugin-hook-prepare-jinja2-environment,plugin_hooks,plugin-hook-prepare-jinja2-environment,"prepare_jinja2_environment(env, datasette)","env - jinja2 Environment The template environment that is being prepared datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) This hook is called with the Jinja2 environment that is used to evaluate Datasette HTML templates. You can use it to do things like register custom template filters , for example: from datasette import hookimpl @hookimpl def prepare_jinja2_environment(env): env.filters[""uppercase""] = lambda u: u.upper() You can now use this filter in your custom templates like so: Table name: {{ table|uppercase }} This function can return an awaitable function if it needs to run any async code. Examples: datasette-edit-templates","[""Plugin hooks""]","[{""href"": ""http://jinja.pocoo.org/docs/2.10/api/#custom-filters"", ""label"": ""register custom\n template filters""}, {""href"": ""https://datasette.io/plugins/datasette-edit-templates"", ""label"": ""datasette-edit-templates""}]" plugin_hooks:plugin-hook-publish-subcommand,plugin_hooks,plugin-hook-publish-subcommand,publish_subcommand(publish),"publish - Click publish command group The Click command group for the datasette publish subcommand This hook allows you to create new providers for the datasette publish command. Datasette uses this hook internally to implement the default cloudrun and heroku subcommands, so you can read their source to see examples of this hook in action. Let's say you want to build a plugin that adds a datasette publish my_hosting_provider --api_key=xxx mydatabase.db publish command. Your implementation would start like this: from datasette import hookimpl from datasette.publish.common import ( add_common_publish_arguments_and_options, ) import click @hookimpl def publish_subcommand(publish): @publish.command() @add_common_publish_arguments_and_options @click.option( ""-k"", ""--api_key"", help=""API key for talking to my hosting provider"", ) def my_hosting_provider( files, metadata, extra_options, branch, template_dir, plugins_dir, static, install, plugin_secret, version_note, secret, title, license, license_url, source, source_url, about, about_url, api_key, ): ... Examples: datasette-publish-fly , datasette-publish-vercel","[""Plugin hooks""]","[{""href"": ""https://github.com/simonw/datasette/tree/main/datasette/publish"", ""label"": ""their source""}, {""href"": ""https://datasette.io/plugins/datasette-publish-fly"", ""label"": ""datasette-publish-fly""}, {""href"": ""https://datasette.io/plugins/datasette-publish-vercel"", ""label"": ""datasette-publish-vercel""}]" plugin_hooks:plugin-hook-query-actions,plugin_hooks,plugin-hook-query-actions,"query_actions(datasette, actor, database, query_name, request, sql, params)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. actor - dictionary or None The currently authenticated actor . database - string The name of the database. query_name - string or None The name of the canned query, or None if this is an arbitrary SQL query. request - Request object The current HTTP request. sql - string The SQL query being executed params - dictionary The parameters passed to the SQL query, if any. Populates a ""Query actions"" menu on the canned query and arbitrary SQL query pages. This example adds a new query action linking to a page for explaining a query: from datasette import hookimpl import urllib @hookimpl def query_actions(datasette, database, query_name, sql): # Don't explain an explain if sql.lower().startswith(""explain""): return return [ { ""href"": datasette.urls.database(database) + ""?"" + urllib.parse.urlencode( { ""sql"": ""explain "" + sql, } ), ""label"": ""Explain this query"", ""description"": ""Get a summary of how SQLite executes the query"", }, ] Example: datasette-create-view","[""Plugin hooks"", ""Action hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-create-view"", ""label"": ""datasette-create-view""}]" plugin_hooks:plugin-hook-register-commands,plugin_hooks,plugin-hook-register-commands,register_commands(cli),"cli - the root Datasette Click command group Use this to register additional CLI commands Register additional CLI commands that can be run using datsette yourcommand ... . This provides a mechanism by which plugins can add new CLI commands to Datasette. This example registers a new datasette verify file1.db file2.db command that checks if the provided file paths are valid SQLite databases: from datasette import hookimpl import click import sqlite3 @hookimpl def register_commands(cli): @cli.command() @click.argument( ""files"", type=click.Path(exists=True), nargs=-1 ) def verify(files): ""Verify that files can be opened by Datasette"" for file in files: conn = sqlite3.connect(str(file)) try: conn.execute(""select * from sqlite_master"") except sqlite3.DatabaseError: raise click.ClickException( ""Invalid database: {}"".format(file) ) The new command can then be executed like so: datasette verify fixtures.db Help text (from the docstring for the function plus any defined Click arguments or options) will become available using: datasette verify --help Plugins can register multiple commands by making multiple calls to the @cli.command() decorator. Consult the Click documentation for full details on how to build a CLI command, including how to define arguments and options. Note that register_commands() plugins cannot used with the --plugins-dir mechanism - they need to be installed into the same virtual environment as Datasette using pip install . Provided it has a setup.py file (see Packaging a plugin ) you can run pip install directly against the directory in which you are developing your plugin like so: pip install -e path/to/my/datasette-plugin Examples: datasette-auth-passwords , datasette-verify","[""Plugin hooks""]","[{""href"": ""https://click.palletsprojects.com/en/latest/commands/#callback-invocation"", ""label"": ""Click command group""}, {""href"": ""https://click.palletsprojects.com/"", ""label"": ""Click documentation""}, {""href"": ""https://datasette.io/plugins/datasette-auth-passwords"", ""label"": ""datasette-auth-passwords""}, {""href"": ""https://datasette.io/plugins/datasette-verify"", ""label"": ""datasette-verify""}]" plugin_hooks:plugin-hook-register-events,plugin_hooks,plugin-hook-register-events,register_events(datasette),"datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) . This hook should return a list of Event subclasses that represent custom events that the plugin might send to the datasette.track_event() method. This example registers event subclasses for ban-user and unban-user events: from dataclasses import dataclass from datasette import hookimpl, Event @dataclass class BanUserEvent(Event): name = ""ban-user"" user: dict @dataclass class UnbanUserEvent(Event): name = ""unban-user"" user: dict @hookimpl def register_events(): return [BanUserEvent, UnbanUserEvent] The plugin can then call datasette.track_event(...) to send a ban-user event: await datasette.track_event( BanUserEvent(user={""id"": 1, ""username"": ""cleverbot""}) )","[""Plugin hooks"", ""Event tracking""]",[] plugin_hooks:plugin-hook-register-magic-parameters,plugin_hooks,plugin-hook-register-magic-parameters,register_magic_parameters(datasette),"datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) . Magic parameters can be used to add automatic parameters to canned queries . This plugin hook allows additional magic parameters to be defined by plugins. Magic parameters all take this format: _prefix_rest_of_parameter . The prefix indicates which magic parameter function should be called - the rest of the parameter is passed as an argument to that function. To register a new function, return it as a tuple of (string prefix, function) from this hook. The function you register should take two arguments: key and request , where key is the rest_of_parameter portion of the parameter and request is the current Request object . This example registers two new magic parameters: :_request_http_version returning the HTTP version of the current request, and :_uuid_new which returns a new UUID: from datasette import hookimpl from uuid import uuid4 def uuid(key, request): if key == ""new"": return str(uuid4()) else: raise KeyError def request(key, request): if key == ""http_version"": return request.scope[""http_version""] else: raise KeyError @hookimpl def register_magic_parameters(datasette): return [ (""request"", request), (""uuid"", uuid), ]","[""Plugin hooks""]",[] plugin_hooks:plugin-hook-render-cell,plugin_hooks,plugin-hook-render-cell,"render_cell(row, value, column, table, database, datasette, request)","Lets you customize the display of values within table cells in the HTML table view. row - sqlite.Row The SQLite row object that the value being rendered is part of value - string, integer, float, bytes or None The value that was loaded from the database column - string The name of the column being rendered table - string or None The name of the table - or None if this is a custom SQL query database - string The name of the database datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. request - Request object The current request object If your hook returns None , it will be ignored. Use this to indicate that your hook is not able to custom render this particular value. If the hook returns a string, that string will be rendered in the table cell. If you want to return HTML markup you can do so by returning a jinja2.Markup object. You can also return an awaitable function which returns a value. Datasette will loop through all available render_cell hooks and display the value returned by the first one that does not return None . Here is an example of a custom render_cell() plugin which looks for values that are a JSON string matching the following format: {""href"": ""https://www.example.com/"", ""label"": ""Name""} If the value matches that pattern, the plugin returns an HTML link element: from datasette import hookimpl import markupsafe import json @hookimpl def render_cell(value): # Render {""href"": ""..."", ""label"": ""...""} as link if not isinstance(value, str): return None stripped = value.strip() if not ( stripped.startswith(""{"") and stripped.endswith(""}"") ): return None try: data = json.loads(value) except ValueError: return None if not isinstance(data, dict): return None if set(data.keys()) != {""href"", ""label""}: return None href = data[""href""] if not ( href.startswith(""/"") or href.startswith(""http://"") or href.startswith(""https://"") ): return None return markupsafe.Markup( '<a href=""{href}"">{label}</a>'.format( href=markupsafe.escape(data[""href""]), label=markupsafe.escape(data[""label""] or """") or "" "", ) ) Examples: datasette-render-binary , datasette-render-markdown , datasette-json-html","[""Plugin hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-render-binary"", ""label"": ""datasette-render-binary""}, {""href"": ""https://datasette.io/plugins/datasette-render-markdown"", ""label"": ""datasette-render-markdown""}, {""href"": ""https://datasette.io/plugins/datasette-json-html"", ""label"": ""datasette-json-html""}]" plugin_hooks:plugin-hook-row-actions,plugin_hooks,plugin-hook-row-actions,"row_actions(datasette, actor, request, database, table, row)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. actor - dictionary or None The currently authenticated actor . request - Request object or None The current HTTP request. database - string The name of the database. table - string The name of the table. row - sqlite.Row The SQLite row object being displayed on the page. Return links for the ""Row actions"" menu shown at the top of the row page. This example displays the row in JSON plus some additional debug information if the user is signed in: from datasette import hookimpl @hookimpl def row_actions(datasette, database, table, actor, row): if actor: return [ { ""href"": datasette.urls.instance(), ""label"": f""Row details for {actor['id']}"", ""description"": json.dumps( dict(row), default=repr ), }, ] Example: datasette-enrichments","[""Plugin hooks"", ""Action hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-enrichments"", ""label"": ""datasette-enrichments""}]" plugin_hooks:plugin-hook-skip-csrf,plugin_hooks,plugin-hook-skip-csrf,"skip_csrf(datasette, scope)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. scope - dictionary The ASGI scope for the incoming HTTP request. This hook can be used to skip CSRF protection for a specific incoming request. For example, you might have a custom path at /submit-comment which is designed to accept comments from anywhere, whether or not the incoming request originated on the site and has an accompanying CSRF token. This example will disable CSRF protection for that specific URL path: from datasette import hookimpl @hookimpl def skip_csrf(scope): return scope[""path""] == ""/submit-comment"" If any of the currently active skip_csrf() plugin hooks return True , CSRF protection will be skipped for the request.","[""Plugin hooks""]","[{""href"": ""https://asgi.readthedocs.io/en/latest/specs/www.html#http-connection-scope"", ""label"": ""ASGI scope""}]" plugin_hooks:plugin-hook-slots,plugin_hooks,plugin-hook-slots,Template slots,"The following set of plugin hooks can be used to return extra HTML content that will be inserted into the corresponding page, directly below the <h1> heading. Multiple plugins can contribute content here. The order in which it is displayed can be controlled using Pluggy's call time order options . Each of these plugin hooks can return either a string or an awaitable function that returns a string.","[""Plugin hooks""]","[{""href"": ""https://pluggy.readthedocs.io/en/stable/#call-time-order"", ""label"": ""call time order options""}]" plugin_hooks:plugin-hook-startup,plugin_hooks,plugin-hook-startup,startup(datasette),"This hook fires when the Datasette application server first starts up. Here is an example that validates required plugin configuration. The server will fail to start and show an error if the validation check fails: @hookimpl def startup(datasette): config = datasette.plugin_config(""my-plugin"") or {} assert ( ""required-setting"" in config ), ""my-plugin requires setting required-setting"" You can also return an async function, which will be awaited on startup. Use this option if you need to execute any database queries, for example this function which creates the my_table database table if it does not yet exist: @hookimpl def startup(datasette): async def inner(): db = datasette.get_database() if ""my_table"" not in await db.table_names(): await db.execute_write( """""" create table my_table (mycol text) """""" ) return inner Potential use-cases: Run some initialization code for the plugin Create database tables that a plugin needs on startup Validate the configuration for a plugin on startup, and raise an error if it is invalid If you are writing unit tests for a plugin that uses this hook and doesn't exercise Datasette by sending any simulated requests through it you will need to explicitly call await ds.invoke_startup() in your tests. An example: @pytest.mark.asyncio async def test_my_plugin(): ds = Datasette() await ds.invoke_startup() # Rest of test goes here Examples: datasette-saved-queries , datasette-init","[""Plugin hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-saved-queries"", ""label"": ""datasette-saved-queries""}, {""href"": ""https://datasette.io/plugins/datasette-init"", ""label"": ""datasette-init""}]" plugin_hooks:plugin-hook-table-actions,plugin_hooks,plugin-hook-table-actions,"table_actions(datasette, actor, database, table, request)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. actor - dictionary or None The currently authenticated actor . database - string The name of the database. table - string The name of the table. request - Request object or None The current HTTP request. This can be None if the request object is not available. This example adds a new table action if the signed in user is ""root"" : from datasette import hookimpl @hookimpl def table_actions(datasette, actor, database, table): if actor and actor.get(""id"") == ""root"": return [ { ""href"": datasette.urls.path( ""/-/edit-schema/{}/{}"".format( database, table ) ), ""label"": ""Edit schema for this table"", ""description"": ""Add, remove, rename or alter columns for this table."", } ] Example: datasette-graphql","[""Plugin hooks"", ""Action hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-graphql"", ""label"": ""datasette-graphql""}]" plugin_hooks:plugin-hook-top-canned-query,plugin_hooks,plugin-hook-top-canned-query,"top_canned_query(datasette, request, database, query_name)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) . request - Request object The current HTTP request. database - string The name of the database. query_name - string The name of the canned query. Returns HTML to be displayed at the top of the canned query page.","[""Plugin hooks"", ""Template slots""]",[] plugin_hooks:plugin-hook-top-database,plugin_hooks,plugin-hook-top-database,"top_database(datasette, request, database)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) . request - Request object The current HTTP request. database - string The name of the database. Returns HTML to be displayed at the top of the database page.","[""Plugin hooks"", ""Template slots""]",[] plugin_hooks:plugin-hook-top-homepage,plugin_hooks,plugin-hook-top-homepage,"top_homepage(datasette, request)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) . request - Request object The current HTTP request. Returns HTML to be displayed at the top of the Datasette homepage.","[""Plugin hooks"", ""Template slots""]",[] plugin_hooks:plugin-hook-top-query,plugin_hooks,plugin-hook-top-query,"top_query(datasette, request, database, sql)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) . request - Request object The current HTTP request. database - string The name of the database. sql - string The SQL query. Returns HTML to be displayed at the top of the query results page.","[""Plugin hooks"", ""Template slots""]",[] plugin_hooks:plugin-hook-top-row,plugin_hooks,plugin-hook-top-row,"top_row(datasette, request, database, table, row)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) . request - Request object The current HTTP request. database - string The name of the database. table - string The name of the table. row - sqlite.Row The SQLite row object being displayed. Returns HTML to be displayed at the top of the row page.","[""Plugin hooks"", ""Template slots""]",[] plugin_hooks:plugin-hook-top-table,plugin_hooks,plugin-hook-top-table,"top_table(datasette, request, database, table)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) . request - Request object The current HTTP request. database - string The name of the database. table - string The name of the table. Returns HTML to be displayed at the top of the table page.","[""Plugin hooks"", ""Template slots""]",[] plugin_hooks:plugin-hook-track-event,plugin_hooks,plugin-hook-track-event,"track_event(datasette, event)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) . event - Event Information about the event, represented as an instance of a subclass of the Event base class. This hook will be called any time an event is tracked by code that calls the datasette.track_event(...) internal method. The event object will always have the following properties: name : a string representing the name of the event, for example logout or create-table . actor : a dictionary representing the actor that triggered the event, or None if the event was not triggered by an actor. created : a datatime.datetime object in the timezone.utc timezone representing the time the event object was created. Other properties on the event will be available depending on the type of event. You can also access those as a dictionary using event.properties() . The events fired by Datasette core are documented here . This example plugin logs details of all events to standard error: from datasette import hookimpl import json import sys @hookimpl def track_event(event): name = event.name actor = event.actor properties = event.properties() msg = json.dumps( { ""name"": name, ""actor"": actor, ""properties"": properties, } ) print(msg, file=sys.stderr, flush=True) The function can also return an async function which will be awaited. This is useful for writing to a database. This example logs events to a datasette_events table in a database called events . It uses the startup() hook to create that table if it does not exist. from datasette import hookimpl import json @hookimpl def startup(datasette): async def inner(): db = datasette.get_database(""events"") await db.execute_write( """""" create table if not exists datasette_events ( id integer primary key, event_type text, created text, actor text, properties text ) """""" ) return inner @hookimpl def track_event(datasette, event): async def inner(): db = datasette.get_database(""events"") properties = event.properties() await db.execute_write( """""" insert into datasette_events (event_type, created, actor, properties) values (?, strftime('%Y-%m-%d %H:%M:%S', 'now'), ?, ?) """""", (event.name, json.dumps(event.actor), json.dumps(properties)), ) return inner Example: datasette-events-db","[""Plugin hooks"", ""Event tracking""]","[{""href"": ""https://datasette.io/plugins/datasette-events-db"", ""label"": ""datasette-events-db""}]" plugin_hooks:plugin-hook-view-actions,plugin_hooks,plugin-hook-view-actions,"view_actions(datasette, actor, database, view, request)","datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. actor - dictionary or None The currently authenticated actor . database - string The name of the database. view - string The name of the SQL view. request - Request object or None The current HTTP request. This can be None if the request object is not available. Like table_actions(datasette, actor, database, table, request) but for SQL views.","[""Plugin hooks"", ""Action hooks""]",[] plugin_hooks:plugin-page-extras,plugin_hooks,plugin-page-extras,Page extras,These plugin hooks can be used to affect the way HTML pages for different Datasette interfaces are rendered.,"[""Plugin hooks""]",[] plugin_hooks:plugin-register-facet-classes,plugin_hooks,plugin-register-facet-classes,register_facet_classes(),"Return a list of additional Facet subclasses to be registered. The design of this plugin hook is unstable and may change. See issue 830 . Each Facet subclass implements a new type of facet operation. The class should look like this: class SpecialFacet(Facet): # This key must be unique across all facet classes: type = ""special"" async def suggest(self): # Use self.sql and self.params to suggest some facets suggested_facets = [] suggested_facets.append( { ""name"": column, # Or other unique name # Construct the URL that will enable this facet: ""toggle_url"": self.ds.absolute_url( self.request, path_with_added_args( self.request, {""_facet"": column} ), ), } ) return suggested_facets async def facet_results(self): # This should execute the facet operation and return results, again # using self.sql and self.params as the starting point facet_results = [] facets_timed_out = [] facet_size = self.get_facet_size() # Do some calculations here... for column in columns_selected_for_facet: try: facet_results_values = [] # More calculations... facet_results_values.append( { ""value"": value, ""label"": label, ""count"": count, ""toggle_url"": self.ds.absolute_url( self.request, toggle_path ), ""selected"": selected, } ) facet_results.append( { ""name"": column, ""results"": facet_results_values, ""truncated"": len(facet_rows_results) > facet_size, } ) except QueryInterrupted: facets_timed_out.append(column) return facet_results, facets_timed_out See datasette/facets.py for examples of how these classes can work. The plugin hook can then be used to register the new facet class like this: @hookimpl def register_facet_classes(): return [SpecialFacet]","[""Plugin hooks""]","[{""href"": ""https://github.com/simonw/datasette/issues/830"", ""label"": ""issue 830""}, {""href"": ""https://github.com/simonw/datasette/blob/main/datasette/facets.py"", ""label"": ""datasette/facets.py""}]" plugin_hooks:plugin-register-output-renderer,plugin_hooks,plugin-register-output-renderer,register_output_renderer(datasette),"datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) Registers a new output renderer, to output data in a custom format. The hook function should return a dictionary, or a list of dictionaries, of the following shape: @hookimpl def register_output_renderer(datasette): return { ""extension"": ""test"", ""render"": render_demo, ""can_render"": can_render_demo, # Optional } This will register render_demo to be called when paths with the extension .test (for example /database.test , /database/table.test , or /database/table/row.test ) are requested. render_demo is a Python function. It can be a regular function or an async def render_demo() awaitable function, depending on if it needs to make any asynchronous calls. can_render_demo is a Python function (or async def function) which accepts the same arguments as render_demo but just returns True or False . It lets Datasette know if the current SQL query can be represented by the plugin - and hence influence if a link to this output format is displayed in the user interface. If you omit the ""can_render"" key from the dictionary every query will be treated as being supported by the plugin. When a request is received, the ""render"" callback function is called with zero or more of the following arguments. Datasette will inspect your callback function and pass arguments that match its function signature. datasette - Datasette class For accessing plugin configuration and executing queries. columns - list of strings The names of the columns returned by this query. rows - list of sqlite3.Row objects The rows returned by the query. sql - string The SQL query that was executed. query_name - string or None If this was the execution of a canned query , the name of that query. database - string The name of the database. table - string or None The table or view, if one is being rendered. request - Request object The current HTTP request. error - string or None If an error occurred this string will contain the error message. truncated - bool or None If the query response was truncated - for example a SQL query returning more than 1,000 results where pagination is not available - this will be True . view_name - string The name of the current view being called. index , database , table , and row are the most important ones. The callback function can return None , if it is unable to render the data, or a Response class that will be returned to the caller. It can also return a dictionary with the following keys. This format is deprecated as-of Datasette 0.49 and will be removed by Datasette 1.0. body - string or bytes, optional The response body, default empty content_type - string, optional The Content-Type header, default text/plain status_code - integer, optional The HTTP status code, default 200 headers - dictionary, optional Extra HTTP headers to be returned in the response. An example of an output renderer callback function: def render_demo(): return Response.text(""Hello World"") Here is a more complex example: async def render_demo(datasette, columns, rows): db = datasette.get_database() result = await db.execute(""select sqlite_version()"") first_row = "" | "".join(columns) lines = [first_row] lines.append(""="" * len(first_row)) for row in rows: lines.append("" | "".join(row)) return Response( ""\n"".join(lines), content_type=""text/plain; charset=utf-8"", headers={""x-sqlite-version"": result.first()[0]}, ) And here is an example can_render function which returns True only if the query results contain the columns atom_id , atom_title and atom_updated : def can_render_demo(columns): return { ""atom_id"", ""atom_title"", ""atom_updated"", }.issubset(columns) Examples: datasette-atom , datasette-ics , datasette-geojson , datasette-copyable","[""Plugin hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-atom"", ""label"": ""datasette-atom""}, {""href"": ""https://datasette.io/plugins/datasette-ics"", ""label"": ""datasette-ics""}, {""href"": ""https://datasette.io/plugins/datasette-geojson"", ""label"": ""datasette-geojson""}, {""href"": ""https://datasette.io/plugins/datasette-copyable"", ""label"": ""datasette-copyable""}]" plugin_hooks:plugin-register-permissions,plugin_hooks,plugin-register-permissions,register_permissions(datasette),"If your plugin needs to register additional permissions unique to that plugin - upload-csvs for example - you can return a list of those permissions from this hook. from datasette import hookimpl, Permission @hookimpl def register_permissions(datasette): return [ Permission( name=""upload-csvs"", abbr=None, description=""Upload CSV files"", takes_database=True, takes_resource=False, default=False, ) ] The fields of the Permission class are as follows: name - string The name of the permission, e.g. upload-csvs . This should be unique across all plugins that the user might have installed, so choose carefully. abbr - string or None An abbreviation of the permission, e.g. uc . This is optional - you can set it to None if you do not want to pick an abbreviation. Since this needs to be unique across all installed plugins it's best not to specify an abbreviation at all. If an abbreviation is provided it will be used when creating restricted signed API tokens. description - string or None A human-readable description of what the permission lets you do. Should make sense as the second part of a sentence that starts ""A user with this permission can ..."". takes_database - boolean True if this permission can be granted on a per-database basis, False if it is only valid at the overall Datasette instance level. takes_resource - boolean True if this permission can be granted on a per-resource basis. A resource is a database table, SQL view or canned query . default - boolean The default value for this permission if it is not explicitly granted to a user. True means the permission is granted by default, False means it is not. This should only be True if you want anonymous users to be able to take this action.","[""Plugin hooks""]",[] plugin_hooks:plugin-register-routes,plugin_hooks,plugin-register-routes,register_routes(datasette),"datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) Register additional view functions to execute for specified URL routes. Return a list of (regex, view_function) pairs, something like this: from datasette import hookimpl, Response import html async def hello_from(request): name = request.url_vars[""name""] return Response.html( ""Hello from {}"".format(html.escape(name)) ) @hookimpl def register_routes(): return [(r""^/hello-from/(?P<name>.*)$"", hello_from)] The view functions can take a number of different optional arguments. The corresponding argument will be passed to your function depending on its named parameters - a form of dependency injection. The optional view function arguments are as follows: datasette - Datasette class You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) , or to execute SQL queries. request - Request object The current HTTP request. scope - dictionary The incoming ASGI scope dictionary. send - function The ASGI send function. receive - function The ASGI receive function. The view function can be a regular function or an async def function, depending on if it needs to use any await APIs. The function can either return a Response class or it can return nothing and instead respond directly to the request using the ASGI send function (for advanced uses only). It can also raise the datasette.NotFound exception to return a 404 not found error, or the datasette.Forbidden exception for a 403 forbidden. See Designing URLs for your plugin for tips on designing the URL routes used by your plugin. Examples: datasette-auth-github , datasette-psutil","[""Plugin hooks""]","[{""href"": ""https://datasette.io/plugins/datasette-auth-github"", ""label"": ""datasette-auth-github""}, {""href"": ""https://datasette.io/plugins/datasette-psutil"", ""label"": ""datasette-psutil""}]" plugins:deploying-plugins-using-datasette-publish,plugins,deploying-plugins-using-datasette-publish,Deploying plugins using datasette publish,"The datasette publish and datasette package commands both take an optional --install argument. You can use this one or more times to tell Datasette to pip install specific plugins as part of the process: datasette publish cloudrun mydb.db --install=datasette-vega You can use the name of a package on PyPI or any of the other valid arguments to pip install such as a URL to a .zip file: datasette publish cloudrun mydb.db \ --install=https://url-to-my-package.zip","[""Plugins"", ""Installing plugins""]",[] plugins:id1,plugins,id1,Plugins,"Datasette's plugin system allows additional features to be implemented as Python code (or front-end JavaScript) which can be wrapped up in a separate Python package. The underlying mechanism uses pluggy . See the Datasette plugins directory for a list of existing plugins, or take a look at the datasette-plugin topic on GitHub. Things you can do with plugins include: Add visualizations to Datasette, for example datasette-cluster-map and datasette-vega . Make new custom SQL functions available for use within Datasette, for example datasette-haversine and datasette-jellyfish . Define custom output formats with custom extensions, for example datasette-atom and datasette-ics . Add template functions that can be called within your Jinja custom templates, for example datasette-render-markdown . Customize how database values are rendered in the Datasette interface, for example datasette-render-binary and datasette-pretty-json . Customize how Datasette's authentication and permissions systems work, for example datasette-auth-passwords and datasette-permissions-sql .",[],"[{""href"": ""https://pluggy.readthedocs.io/"", ""label"": ""pluggy""}, {""href"": ""https://datasette.io/plugins"", ""label"": ""Datasette plugins directory""}, {""href"": ""https://github.com/topics/datasette-plugin"", ""label"": ""datasette-plugin""}, {""href"": ""https://github.com/simonw/datasette-cluster-map"", ""label"": ""datasette-cluster-map""}, {""href"": ""https://github.com/simonw/datasette-vega"", ""label"": ""datasette-vega""}, {""href"": ""https://github.com/simonw/datasette-haversine"", ""label"": ""datasette-haversine""}, {""href"": ""https://github.com/simonw/datasette-jellyfish"", ""label"": ""datasette-jellyfish""}, {""href"": ""https://github.com/simonw/datasette-atom"", ""label"": ""datasette-atom""}, {""href"": ""https://github.com/simonw/datasette-ics"", ""label"": ""datasette-ics""}, {""href"": ""https://github.com/simonw/datasette-render-markdown#markdown-in-templates"", ""label"": ""datasette-render-markdown""}, {""href"": ""https://github.com/simonw/datasette-render-binary"", ""label"": ""datasette-render-binary""}, {""href"": ""https://github.com/simonw/datasette-pretty-json"", ""label"": ""datasette-pretty-json""}, {""href"": ""https://github.com/simonw/datasette-auth-passwords"", ""label"": ""datasette-auth-passwords""}, {""href"": ""https://github.com/simonw/datasette-permissions-sql"", ""label"": ""datasette-permissions-sql""}]" plugins:one-off-plugins-using-plugins-dir,plugins,one-off-plugins-using-plugins-dir,One-off plugins using --plugins-dir,"You can also define one-off per-project plugins by saving them as plugin_name.py functions in a plugins/ folder and then passing that folder to datasette using the --plugins-dir option: datasette mydb.db --plugins-dir=plugins/","[""Plugins"", ""Installing plugins""]",[] plugins:plugins-configuration,plugins,plugins-configuration,Plugin configuration,"Plugins can have their own configuration, embedded in a configuration file . Configuration options for plugins live within a ""plugins"" key in that file, which can be included at the root, database or table level. Here is an example of some plugin configuration for a specific table: [[[cog from metadata_doc import config_example config_example(cog, { ""databases"": { ""sf-trees"": { ""tables"": { ""Street_Tree_List"": { ""plugins"": { ""datasette-cluster-map"": { ""latitude_column"": ""lat"", ""longitude_column"": ""lng"" } } } } } } }) ]]] [[[end]]] This tells the datasette-cluster-map column which latitude and longitude columns should be used for a table called Street_Tree_List inside a database file called sf-trees.db .","[""Plugins""]",[] plugins:plugins-configuration-secret,plugins,plugins-configuration-secret,Secret configuration values,"Some plugins may need configuration that should stay secret - API keys for example. There are two ways in which you can store secret configuration values. As environment variables . If your secret lives in an environment variable that is available to the Datasette process, you can indicate that the configuration value should be read from that environment variable like so: [[[cog config_example(cog, { ""plugins"": { ""datasette-auth-github"": { ""client_secret"": { ""$env"": ""GITHUB_CLIENT_SECRET"" } } } }) ]]] [[[end]]] As values in separate files . Your secrets can also live in files on disk. To specify a secret should be read from a file, provide the full file path like this: [[[cog config_example(cog, { ""plugins"": { ""datasette-auth-github"": { ""client_secret"": { ""$file"": ""/secrets/client-secret"" } } } }) ]]] [[[end]]] If you are publishing your data using the datasette publish family of commands, you can use the --plugin-secret option to set these secrets at publish time. For example, using Heroku you might run the following command: datasette publish heroku my_database.db \ --name my-heroku-app-demo \ --install=datasette-auth-github \ --plugin-secret datasette-auth-github client_id your_client_id \ --plugin-secret datasette-auth-github client_secret your_client_secret This will set the necessary environment variables and add the following to the deployed metadata.yaml : [[[cog config_example(cog, { ""plugins"": { ""datasette-auth-github"": { ""client_id"": { ""$env"": ""DATASETTE_AUTH_GITHUB_CLIENT_ID"" }, ""client_secret"": { ""$env"": ""DATASETTE_AUTH_GITHUB_CLIENT_SECRET"" } } } }) ]]] [[[end]]]","[""Plugins"", ""Plugin configuration""]",[] plugins:plugins-datasette-load-plugins,plugins,plugins-datasette-load-plugins,Controlling which plugins are loaded,"Datasette defaults to loading every plugin that is installed in the same virtual environment as Datasette itself. You can set the DATASETTE_LOAD_PLUGINS environment variable to a comma-separated list of plugin names to load a controlled subset of plugins instead. For example, to load just the datasette-vega and datasette-cluster-map plugins, set DATASETTE_LOAD_PLUGINS to datasette-vega,datasette-cluster-map : export DATASETTE_LOAD_PLUGINS='datasette-vega,datasette-cluster-map' datasette mydb.db Or: DATASETTE_LOAD_PLUGINS='datasette-vega,datasette-cluster-map' \ datasette mydb.db To disable the loading of all additional plugins, set DATASETTE_LOAD_PLUGINS to an empty string: export DATASETTE_LOAD_PLUGINS='' datasette mydb.db A quick way to test this setting is to use it with the datasette plugins command: DATASETTE_LOAD_PLUGINS='datasette-vega' datasette plugins This should output the following: [ { ""name"": ""datasette-vega"", ""static"": true, ""templates"": false, ""version"": ""0.6.2"", ""hooks"": [ ""extra_css_urls"", ""extra_js_urls"" ] } ]","[""Plugins""]",[] plugins:plugins-installed,plugins,plugins-installed,Seeing what plugins are installed,"You can see a list of installed plugins by navigating to the /-/plugins page of your Datasette instance - for example: https://fivethirtyeight.datasettes.com/-/plugins You can also use the datasette plugins command: datasette plugins Which outputs: [ { ""name"": ""datasette_json_html"", ""static"": false, ""templates"": false, ""version"": ""0.4.0"" } ] [[[cog from datasette import cli from click.testing import CliRunner import textwrap, json cog.out(""\n"") result = CliRunner().invoke(cli.cli, [""plugins"", ""--all""]) # cog.out() with text containing newlines was unindenting for some reason cog.outl(""If you run ``datasette plugins --all`` it will include default plugins that ship as part of Datasette:\n"") cog.outl("".. code-block:: json\n"") plugins = [p for p in json.loads(result.output) if p[""name""].startswith(""datasette."")] indented = textwrap.indent(json.dumps(plugins, indent=4), "" "") for line in indented.split(""\n""): cog.outl(line) cog.out(""\n\n"") ]]] If you run datasette plugins --all it will include default plugins that ship as part of Datasette: [ { ""name"": ""datasette.actor_auth_cookie"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""actor_from_request"" ] }, { ""name"": ""datasette.blob_renderer"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""register_output_renderer"" ] }, { ""name"": ""datasette.default_magic_parameters"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""register_magic_parameters"" ] }, { ""name"": ""datasette.default_menu_links"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""menu_links"" ] }, { ""name"": ""datasette.default_permissions"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""actor_from_request"", ""permission_allowed"", ""register_permissions"", ""skip_csrf"" ] }, { ""name"": ""datasette.events"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""register_events"" ] }, { ""name"": ""datasette.facets"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""register_facet_classes"" ] }, { ""name"": ""datasette.filters"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""filters_from_request"" ] }, { ""name"": ""datasette.forbidden"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""forbidden"" ] }, { ""name"": ""datasette.handle_exception"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""handle_exception"" ] }, { ""name"": ""datasette.publish.cloudrun"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""publish_subcommand"" ] }, { ""name"": ""datasette.publish.heroku"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""publish_subcommand"" ] }, { ""name"": ""datasette.sql_functions"", ""static"": false, ""templates"": false, ""version"": null, ""hooks"": [ ""prepare_connection"" ] } ] [[[end]]] You can add the --plugins-dir= option to include any plugins found in that directory. Add --requirements to output a list of installed plugins that can then be installed in another Datasette instance using datasette install -r requirements.txt : datasette plugins --requirements The output will look something like this: datasette-codespaces==0.1.1 datasette-graphql==2.2 datasette-json-html==1.0.1 datasette-pretty-json==0.2.2 datasette-x-forwarded-host==0.1 To write that to a requirements.txt file, run this: datasette plugins --requirements > requirements.txt","[""Plugins""]","[{""href"": ""https://fivethirtyeight.datasettes.com/-/plugins"", ""label"": ""https://fivethirtyeight.datasettes.com/-/plugins""}]" plugins:plugins-installing,plugins,plugins-installing,Installing plugins,"If a plugin has been packaged for distribution using setuptools you can use the plugin by installing it alongside Datasette in the same virtual environment or Docker container. You can install plugins using the datasette install command: datasette install datasette-vega You can uninstall plugins with datasette uninstall : datasette uninstall datasette-vega You can upgrade plugins with datasette install --upgrade or datasette install -U : datasette install -U datasette-vega This command can also be used to upgrade Datasette itself to the latest released version: datasette install -U datasette You can install multiple plugins at once by listing them as lines in a requirements.txt file like this: datasette-vega datasette-cluster-map Then pass that file to datasette install -r : datasette install -r requirements.txt The install and uninstall commands are thin wrappers around pip install and pip uninstall , which ensure that they run pip in the same virtual environment as Datasette itself.","[""Plugins""]",[] publish:cli-package,publish,cli-package,datasette package,"If you have docker installed (e.g. using Docker for Mac ) you can use the datasette package command to create a new Docker image in your local repository containing the datasette app bundled together with one or more SQLite databases: datasette package mydatabase.db Here's example output for the package command: datasette package parlgov.db --extra-options=""--setting sql_time_limit_ms 2500"" Sending build context to Docker daemon 4.459MB Step 1/7 : FROM python:3.11.0-slim-bullseye ---> 79e1dc9af1c1 Step 2/7 : COPY . /app ---> Using cache ---> cd4ec67de656 Step 3/7 : WORKDIR /app ---> Using cache ---> 139699e91621 Step 4/7 : RUN pip install datasette ---> Using cache ---> 340efa82bfd7 Step 5/7 : RUN datasette inspect parlgov.db --inspect-file inspect-data.json ---> Using cache ---> 5fddbe990314 Step 6/7 : EXPOSE 8001 ---> Using cache ---> 8e83844b0fed Step 7/7 : CMD datasette serve parlgov.db --port 8001 --inspect-file inspect-data.json --setting sql_time_limit_ms 2500 ---> Using cache ---> 1bd380ea8af3 Successfully built 1bd380ea8af3 You can now run the resulting container like so: docker run -p 8081:8001 1bd380ea8af3 This exposes port 8001 inside the container as port 8081 on your host machine, so you can access the application at http://localhost:8081/ You can customize the port that is exposed by the container using the --port option: datasette package mydatabase.db --port 8080 A full list of options can be seen by running datasette package --help : See datasette package for the full list of options for this command.","[""Publishing data""]","[{""href"": ""https://www.docker.com/docker-mac"", ""label"": ""Docker for Mac""}]" publish:cli-publish,publish,cli-publish,datasette publish,"Once you have created a SQLite database (e.g. using csvs-to-sqlite ) you can deploy it to a hosting account using a single command. You will need a hosting account with Heroku or Google Cloud . Once you have created your account you will need to install and configure the heroku or gcloud command-line tools.","[""Publishing data""]","[{""href"": ""https://github.com/simonw/csvs-to-sqlite/"", ""label"": ""csvs-to-sqlite""}, {""href"": ""https://www.heroku.com/"", ""label"": ""Heroku""}, {""href"": ""https://cloud.google.com/"", ""label"": ""Google Cloud""}]" publish:publish-cloud-run,publish,publish-cloud-run,Publishing to Google Cloud Run,"Google Cloud Run allows you to publish data in a scale-to-zero environment, so your application will start running when the first request is received and will shut down again when traffic ceases. This means you only pay for time spent serving traffic. Cloud Run is a great option for inexpensively hosting small, low traffic projects - but costs can add up for projects that serve a lot of requests. Be particularly careful if your project has tables with large numbers of rows. Search engine crawlers that index a page for every row could result in a high bill. The datasette-block-robots plugin can be used to request search engine crawlers omit crawling your site, which can help avoid this issue. You will first need to install and configure the Google Cloud CLI tools by following these instructions . You can then publish one or more SQLite database files to Google Cloud Run using the following command: datasette publish cloudrun mydatabase.db --service=my-database A Cloud Run service is a single hosted application. The service name you specify will be used as part of the Cloud Run URL. If you deploy to a service name that you have used in the past your new deployment will replace the previous one. If you omit the --service option you will be asked to pick a service name interactively during the deploy. You may need to interact with prompts from the tool. Many of the prompts ask for values that can be set as properties for the Google Cloud SDK if you want to avoid the prompts. For example, the default region for the deployed instance can be set using the command: gcloud config set run/region us-central1 You should replace us-central1 with your desired region . Alternately, you can specify the region by setting the CLOUDSDK_RUN_REGION environment variable. Once it has finished it will output a URL like this one: Service [my-service] revision [my-service-00001] has been deployed and is serving traffic at https://my-service-j7hipcg4aq-uc.a.run.app Cloud Run provides a URL on the .run.app domain, but you can also point your own domain or subdomain at your Cloud Run service - see mapping custom domains in the Cloud Run documentation for details. See datasette publish cloudrun for the full list of options for this command.","[""Publishing data"", ""datasette publish""]","[{""href"": ""https://cloud.google.com/run/"", ""label"": ""Google Cloud Run""}, {""href"": ""https://datasette.io/plugins/datasette-block-robots"", ""label"": ""datasette-block-robots""}, {""href"": ""https://cloud.google.com/sdk/"", ""label"": ""these instructions""}, {""href"": ""https://cloud.google.com/sdk/docs/properties"", ""label"": ""set as properties for the Google Cloud SDK""}, {""href"": ""https://cloud.google.com/about/locations"", ""label"": ""region""}, {""href"": ""https://cloud.google.com/run/docs/mapping-custom-domains"", ""label"": ""mapping custom domains""}]" publish:publish-custom-metadata-and-plugins,publish,publish-custom-metadata-and-plugins,Custom metadata and plugins,"datasette publish accepts a number of additional options which can be used to further customize your Datasette instance. You can define your own Metadata and deploy that with your instance like so: datasette publish cloudrun --service=my-service mydatabase.db -m metadata.json If you just want to set the title, license or source information you can do that directly using extra options to datasette publish : datasette publish cloudrun mydatabase.db --service=my-service \ --title=""Title of my database"" \ --source=""Where the data originated"" \ --source_url=""http://www.example.com/"" You can also specify plugins you would like to install. For example, if you want to include the datasette-vega visualization plugin you can use the following: datasette publish cloudrun mydatabase.db --service=my-service --install=datasette-vega If a plugin has any Secret configuration values you can use the --plugin-secret option to set those secrets at publish time. For example, using Heroku with datasette-auth-github you might run the following command: datasette publish heroku my_database.db \ --name my-heroku-app-demo \ --install=datasette-auth-github \ --plugin-secret datasette-auth-github client_id your_client_id \ --plugin-secret datasette-auth-github client_secret your_client_secret","[""Publishing data"", ""datasette publish""]","[{""href"": ""https://github.com/simonw/datasette-vega"", ""label"": ""datasette-vega""}, {""href"": ""https://github.com/simonw/datasette-auth-github"", ""label"": ""datasette-auth-github""}]" publish:publish-fly,publish,publish-fly,Publishing to Fly,"Fly is a competitively priced Docker-compatible hosting platform that supports running applications in globally distributed data centers close to your end users. You can deploy Datasette instances to Fly using the datasette-publish-fly plugin. pip install datasette-publish-fly datasette publish fly mydatabase.db --app=""my-app"" Consult the datasette-publish-fly README for more details.","[""Publishing data"", ""datasette publish""]","[{""href"": ""https://fly.io/"", ""label"": ""Fly""}, {""href"": ""https://fly.io/docs/pricing/"", ""label"": ""competitively priced""}, {""href"": ""https://github.com/simonw/datasette-publish-fly"", ""label"": ""datasette-publish-fly""}, {""href"": ""https://github.com/simonw/datasette-publish-fly/blob/main/README.md"", ""label"": ""datasette-publish-fly README""}]" publish:publish-heroku,publish,publish-heroku,Publishing to Heroku,"To publish your data using Heroku , first create an account there and install and configure the Heroku CLI tool . You can publish one or more databases to Heroku using the following command: datasette publish heroku mydatabase.db This will output some details about the new deployment, including a URL like this one: https://limitless-reef-88278.herokuapp.com/ deployed to Heroku You can specify a custom app name by passing -n my-app-name to the publish command. This will also allow you to overwrite an existing app. Rather than deploying directly you can use the --generate-dir option to output the files that would be deployed to a directory: datasette publish heroku mydatabase.db --generate-dir=/tmp/deploy-this-to-heroku See datasette publish heroku for the full list of options for this command.","[""Publishing data"", ""datasette publish""]","[{""href"": ""https://www.heroku.com/"", ""label"": ""Heroku""}, {""href"": ""https://devcenter.heroku.com/articles/heroku-cli"", ""label"": ""Heroku CLI tool""}]" publish:publish-vercel,publish,publish-vercel,Publishing to Vercel,"Vercel - previously known as Zeit Now - provides a layer over AWS Lambda to allow for quick, scale-to-zero deployment. You can deploy Datasette instances to Vercel using the datasette-publish-vercel plugin. pip install datasette-publish-vercel datasette publish vercel mydatabase.db --project my-database-project Not every feature is supported: consult the datasette-publish-vercel README for more details.","[""Publishing data"", ""datasette publish""]","[{""href"": ""https://vercel.com/"", ""label"": ""Vercel""}, {""href"": ""https://github.com/simonw/datasette-publish-vercel"", ""label"": ""datasette-publish-vercel""}, {""href"": ""https://github.com/simonw/datasette-publish-vercel/blob/main/README.md"", ""label"": ""datasette-publish-vercel README""}]" publish:publishing,publish,publishing,Publishing data,Datasette includes tools for publishing and deploying your data to the internet. The datasette publish command will deploy a new Datasette instance containing your databases directly to a Heroku or Google Cloud hosting account. You can also use datasette package to create a Docker image that bundles your databases together with the datasette application that is used to serve them.,[],[] settings:config-dir,settings,config-dir,Configuration directory mode,"Normally you configure Datasette using command-line options. For a Datasette instance with custom templates, custom plugins, a static directory and several databases this can get quite verbose: datasette one.db two.db \ --metadata=metadata.json \ --template-dir=templates/ \ --plugins-dir=plugins \ --static css:css As an alternative to this, you can run Datasette in configuration directory mode. Create a directory with the following structure: # In a directory called my-app: my-app/one.db my-app/two.db my-app/datasette.yaml my-app/metadata.json my-app/templates/index.html my-app/plugins/my_plugin.py my-app/static/my.css Now start Datasette by providing the path to that directory: datasette my-app/ Datasette will detect the files in that directory and automatically configure itself using them. It will serve all *.db files that it finds, will load metadata.json if it exists, and will load the templates , plugins and static folders if they are present. The files that can be included in this directory are as follows. All are optional. *.db (or *.sqlite3 or *.sqlite ) - SQLite database files that will be served by Datasette datasette.yaml - Configuration for the Datasette instance metadata.json - Metadata for those databases - metadata.yaml or metadata.yml can be used as well inspect-data.json - the result of running datasette inspect *.db --inspect-file=inspect-data.json from the configuration directory - any database files listed here will be treated as immutable, so they should not be changed while Datasette is running templates/ - a directory containing Custom templates plugins/ - a directory containing plugins, see Writing one-off plugins static/ - a directory containing static files - these will be served from /static/filename.txt , see Serving static files","[""Settings""]",[] settings:id1,settings,id1,Settings,,[],[] settings:id2,settings,id2,Settings,"The following options can be set using --setting name value , or by storing them in the settings.json file for use with Configuration directory mode .","[""Settings""]",[] settings:setting-allow-csv-stream,settings,setting-allow-csv-stream,allow_csv_stream,"Enables the CSV export feature where an entire table (potentially hundreds of thousands of rows) can be exported as a single CSV file. This is turned on by default - you can turn it off like this: datasette mydatabase.db --setting allow_csv_stream off","[""Settings"", ""Settings""]",[] settings:setting-allow-download,settings,setting-allow-download,allow_download,"Should users be able to download the original SQLite database using a link on the database index page? This is turned on by default. However, databases can only be downloaded if they are served in immutable mode and not in-memory. If downloading is unavailable for either of these reasons, the download link is hidden even if allow_download is on. To disable database downloads, use the following: datasette mydatabase.db --setting allow_download off","[""Settings"", ""Settings""]",[] settings:setting-allow-facet,settings,setting-allow-facet,allow_facet,"Allow users to specify columns they would like to facet on using the ?_facet=COLNAME URL parameter to the table view. This is enabled by default. If disabled, facets will still be displayed if they have been specifically enabled in metadata.json configuration for the table. Here's how to disable this feature: datasette mydatabase.db --setting allow_facet off","[""Settings"", ""Settings""]",[] settings:setting-allow-signed-tokens,settings,setting-allow-signed-tokens,allow_signed_tokens,"Should users be able to create signed API tokens to access Datasette? This is turned on by default. Use the following to turn it off: datasette mydatabase.db --setting allow_signed_tokens off Turning this setting off will disable the /-/create-token page, described here . It will also cause any incoming Authorization: Bearer dstok_... API tokens to be ignored.","[""Settings"", ""Settings""]",[] settings:setting-base-url,settings,setting-base-url,base_url,"If you are running Datasette behind a proxy, it may be useful to change the root path used for the Datasette instance. For example, if you are sending traffic from https://www.example.com/tools/datasette/ through to a proxied Datasette instance you may wish Datasette to use /tools/datasette/ as its root URL. You can do that like so: datasette mydatabase.db --setting base_url /tools/datasette/","[""Settings"", ""Settings""]",[] settings:setting-cache-size-kb,settings,setting-cache-size-kb,cache_size_kb,"Sets the amount of memory SQLite uses for its per-connection cache , in KB. datasette mydatabase.db --setting cache_size_kb 5000","[""Settings"", ""Settings""]","[{""href"": ""https://www.sqlite.org/pragma.html#pragma_cache_size"", ""label"": ""per-connection cache""}]" settings:setting-default-allow-sql,settings,setting-default-allow-sql,default_allow_sql,"Should users be able to execute arbitrary SQL queries by default? Setting this to off causes permission checks for execute-sql to fail by default. datasette mydatabase.db --setting default_allow_sql off Another way to achieve this is to add ""allow_sql"": false to your datasette.yaml file, as described in Controlling the ability to execute arbitrary SQL . This setting offers a more convenient way to do this.","[""Settings"", ""Settings""]",[] settings:setting-default-cache-ttl,settings,setting-default-cache-ttl,default_cache_ttl,"Default HTTP caching max-age header in seconds, used for Cache-Control: max-age=X . Can be over-ridden on a per-request basis using the ?_ttl= query string parameter. Set this to 0 to disable HTTP caching entirely. Defaults to 5 seconds. datasette mydatabase.db --setting default_cache_ttl 60","[""Settings"", ""Settings""]",[] settings:setting-default-facet-size,settings,setting-default-facet-size,default_facet_size,"The default number of unique rows returned by Facets is 30. You can customize it like this: datasette mydatabase.db --setting default_facet_size 50","[""Settings"", ""Settings""]",[] settings:setting-default-page-size,settings,setting-default-page-size,default_page_size,"The default number of rows returned by the table page. You can over-ride this on a per-page basis using the ?_size=80 query string parameter, provided you do not specify a value higher than the max_returned_rows setting. You can set this default using --setting like so: datasette mydatabase.db --setting default_page_size 50","[""Settings"", ""Settings""]",[] settings:setting-facet-suggest-time-limit-ms,settings,setting-facet-suggest-time-limit-ms,facet_suggest_time_limit_ms,"When Datasette calculates suggested facets it needs to run a SQL query for every column in your table. The default for this time limit is 50ms to account for the fact that it needs to run once for every column. If the time limit is exceeded the column will not be suggested as a facet. You can increase this time limit like so: datasette mydatabase.db --setting facet_suggest_time_limit_ms 500","[""Settings"", ""Settings""]",[] settings:setting-facet-time-limit-ms,settings,setting-facet-time-limit-ms,facet_time_limit_ms,"This is the time limit Datasette allows for calculating a facet, which defaults to 200ms: datasette mydatabase.db --setting facet_time_limit_ms 1000","[""Settings"", ""Settings""]",[] settings:setting-force-https-urls,settings,setting-force-https-urls,force_https_urls,"Forces self-referential URLs in the JSON output to always use the https:// protocol. This is useful for cases where the application itself is hosted using HTTP but is served to the outside world via a proxy that enables HTTPS. datasette mydatabase.db --setting force_https_urls 1","[""Settings"", ""Settings""]",[] settings:setting-max-csv-mb,settings,setting-max-csv-mb,max_csv_mb,"The maximum size of CSV that can be exported, in megabytes. Defaults to 100MB. You can disable the limit entirely by settings this to 0: datasette mydatabase.db --setting max_csv_mb 0","[""Settings"", ""Settings""]",[] settings:setting-max-insert-rows,settings,setting-max-insert-rows,max_insert_rows,"Maximum rows that can be inserted at a time using the bulk insert API, see Inserting rows . Defaults to 100. You can increase or decrease this limit like so: datasette mydatabase.db --setting max_insert_rows 1000","[""Settings"", ""Settings""]",[] settings:setting-max-returned-rows,settings,setting-max-returned-rows,max_returned_rows,"Datasette returns a maximum of 1,000 rows of data at a time. If you execute a query that returns more than 1,000 rows, Datasette will return the first 1,000 and include a warning that the result set has been truncated. You can use OFFSET/LIMIT or other methods in your SQL to implement pagination if you need to return more than 1,000 rows. You can increase or decrease this limit like so: datasette mydatabase.db --setting max_returned_rows 2000","[""Settings"", ""Settings""]",[] settings:setting-max-signed-tokens-ttl,settings,setting-max-signed-tokens-ttl,max_signed_tokens_ttl,"Maximum allowed expiry time for signed API tokens created by users. Defaults to 0 which means no limit - tokens can be created that will never expire. Set this to a value in seconds to limit the maximum expiry time. For example, to set that limit to 24 hours you would use: datasette mydatabase.db --setting max_signed_tokens_ttl 86400 This setting is enforced when incoming tokens are processed.","[""Settings"", ""Settings""]",[] settings:setting-num-sql-threads,settings,setting-num-sql-threads,num_sql_threads,"Maximum number of threads in the thread pool Datasette uses to execute SQLite queries. Defaults to 3. datasette mydatabase.db --setting num_sql_threads 10 Setting this to 0 turns off threaded SQL queries entirely - useful for environments that do not support threading such as Pyodide .","[""Settings"", ""Settings""]","[{""href"": ""https://pyodide.org/"", ""label"": ""Pyodide""}]" settings:setting-publish-secrets,settings,setting-publish-secrets,Using secrets with datasette publish,"The datasette publish and datasette package commands both generate a secret for you automatically when Datasette is deployed. This means that every time you deploy a new version of a Datasette project, a new secret will be generated. This will cause signed cookies to become invalid on every fresh deploy. You can fix this by creating a secret that will be used for multiple deploys and passing it using the --secret option: datasette publish cloudrun mydb.db --service=my-service --secret=cdb19e94283a20f9d42cca5","[""Settings""]",[] settings:setting-secret,settings,setting-secret,Configuring the secret,"Datasette uses a secret string to sign secure values such as cookies. If you do not provide a secret, Datasette will create one when it starts up. This secret will reset every time the Datasette server restarts though, so things like authentication cookies and API tokens will not stay valid between restarts. You can pass a secret to Datasette in two ways: with the --secret command-line option or by setting a DATASETTE_SECRET environment variable. datasette mydb.db --secret=SECRET_VALUE_HERE Or: export DATASETTE_SECRET=SECRET_VALUE_HERE datasette mydb.db One way to generate a secure random secret is to use Python like this: python3 -c 'import secrets; print(secrets.token_hex(32))' cdb19e94283a20f9d42cca50c5a4871c0aa07392db308755d60a1a5b9bb0fa52 Plugin authors make use of this signing mechanism in their plugins using .sign(value, namespace=""default"") and .unsign(value, namespace=""default"") .","[""Settings""]",[] settings:setting-sql-time-limit-ms,settings,setting-sql-time-limit-ms,sql_time_limit_ms,"By default, queries have a time limit of one second. If a query takes longer than this to run Datasette will terminate the query and return an error. If this time limit is too short for you, you can customize it using the sql_time_limit_ms limit - for example, to increase it to 3.5 seconds: datasette mydatabase.db --setting sql_time_limit_ms 3500 You can optionally set a lower time limit for an individual query using the ?_timelimit=100 query string argument: /my-database/my-table?qSpecies=44&_timelimit=100 This would set the time limit to 100ms for that specific query. This feature is useful if you are working with databases of unknown size and complexity - a query that might make perfect sense for a smaller table could take too long to execute on a table with millions of rows. By setting custom time limits you can execute queries ""optimistically"" - e.g. give me an exact count of rows matching this query but only if it takes less than 100ms to calculate.","[""Settings"", ""Settings""]",[] settings:setting-suggest-facets,settings,setting-suggest-facets,suggest_facets,"Should Datasette calculate suggested facets? On by default, turn this off like so: datasette mydatabase.db --setting suggest_facets off","[""Settings"", ""Settings""]",[] settings:setting-template-debug,settings,setting-template-debug,template_debug,"This setting enables template context debug mode, which is useful to help understand what variables are available to custom templates when you are writing them. Enable it like this: datasette mydatabase.db --setting template_debug 1 Now you can add ?_context=1 or &_context=1 to any Datasette page to see the context that was passed to that template. Some examples: https://latest.datasette.io/?_context=1 https://latest.datasette.io/fixtures?_context=1 https://latest.datasette.io/fixtures/roadside_attractions?_context=1","[""Settings"", ""Settings""]","[{""href"": ""https://latest.datasette.io/?_context=1"", ""label"": ""https://latest.datasette.io/?_context=1""}, {""href"": ""https://latest.datasette.io/fixtures?_context=1"", ""label"": ""https://latest.datasette.io/fixtures?_context=1""}, {""href"": ""https://latest.datasette.io/fixtures/roadside_attractions?_context=1"", ""label"": ""https://latest.datasette.io/fixtures/roadside_attractions?_context=1""}]" settings:setting-trace-debug,settings,setting-trace-debug,trace_debug,"This setting enables appending ?_trace=1 to any page in order to see the SQL queries and other trace information that was used to generate that page. Enable it like this: datasette mydatabase.db --setting trace_debug 1 Some examples: https://latest.datasette.io/?_trace=1 https://latest.datasette.io/fixtures/roadside_attractions?_trace=1 See datasette.tracer for details on how to hook into this mechanism as a plugin author.","[""Settings"", ""Settings""]","[{""href"": ""https://latest.datasette.io/?_trace=1"", ""label"": ""https://latest.datasette.io/?_trace=1""}, {""href"": ""https://latest.datasette.io/fixtures/roadside_attractions?_trace=1"", ""label"": ""https://latest.datasette.io/fixtures/roadside_attractions?_trace=1""}]" settings:setting-truncate-cells-html,settings,setting-truncate-cells-html,truncate_cells_html,"In the HTML table view, truncate any strings that are longer than this value. The full value will still be available in CSV, JSON and on the individual row HTML page. Set this to 0 to disable truncation. datasette mydatabase.db --setting truncate_cells_html 0","[""Settings"", ""Settings""]",[] settings:using-setting,settings,using-setting,Using --setting,"Datasette supports a number of settings. These can be set using the --setting name value option to datasette serve . You can set multiple settings at once like this: datasette mydatabase.db \ --setting default_page_size 50 \ --setting sql_time_limit_ms 3500 \ --setting max_returned_rows 2000 Settings can also be specified in the database.yaml configuration file .","[""Settings""]",[] spatialite:id1,spatialite,id1,SpatiaLite,"The SpatiaLite module for SQLite adds features for handling geographic and spatial data. For an example of what you can do with it, see the tutorial Building a location to time zone API with SpatiaLite . To use it with Datasette, you need to install the mod_spatialite dynamic library. This can then be loaded into Datasette using the --load-extension command-line option. Datasette can look for SpatiaLite in common installation locations if you run it like this: datasette --load-extension=spatialite --setting default_allow_sql off If SpatiaLite is in another location, use the full path to the extension instead: datasette --setting default_allow_sql off \ --load-extension=/usr/local/lib/mod_spatialite.dylib",[],"[{""href"": ""https://www.gaia-gis.it/fossil/libspatialite/index"", ""label"": ""SpatiaLite module""}, {""href"": ""https://datasette.io/tutorials/spatialite"", ""label"": ""Building a location to time zone API with SpatiaLite""}]" spatialite:importing-geojson-polygons-using-shapely,spatialite,importing-geojson-polygons-using-shapely,Importing GeoJSON polygons using Shapely,"Another common form of polygon data is the GeoJSON format. This can be imported into SpatiaLite directly, or by using the Shapely Python library. Who's On First is an excellent source of openly licensed GeoJSON polygons. Let's import the geographical polygon for Wales. First, we can use the Who's On First Spelunker tool to find the record for Wales: spelunker.whosonfirst.org/id/404227475 That page includes a link to the GeoJSON record, which can be accessed here: data.whosonfirst.org/404/227/475/404227475.geojson Here's Python code to create a SQLite database, enable SpatiaLite, create a places table and then add a record for Wales: import sqlite3 conn = sqlite3.connect(""places.db"") # Enable SpatialLite extension conn.enable_load_extension(True) conn.load_extension(""/usr/local/lib/mod_spatialite.dylib"") # Create the masic countries table conn.execute(""select InitSpatialMetadata(1)"") conn.execute( ""create table places (id integer primary key, name text);"" ) # Add a MULTIPOLYGON Geometry column conn.execute( ""SELECT AddGeometryColumn('places', 'geom', 4326, 'MULTIPOLYGON', 2);"" ) # Add a spatial index against the new column conn.execute(""SELECT CreateSpatialIndex('places', 'geom');"") # Now populate the table from shapely.geometry.multipolygon import MultiPolygon from shapely.geometry import shape import requests geojson = requests.get( ""https://data.whosonfirst.org/404/227/475/404227475.geojson"" ).json() # Convert to ""Well Known Text"" format wkt = shape(geojson[""geometry""]).wkt # Insert and commit the record conn.execute( ""INSERT INTO places (id, name, geom) VALUES(null, ?, GeomFromText(?, 4326))"", (""Wales"", wkt), ) conn.commit()","[""SpatiaLite""]","[{""href"": ""https://pypi.org/project/Shapely/"", ""label"": ""Shapely""}, {""href"": ""https://whosonfirst.org/"", ""label"": ""Who's On First""}, {""href"": ""https://spelunker.whosonfirst.org/id/404227475/"", ""label"": ""spelunker.whosonfirst.org/id/404227475""}, {""href"": ""https://data.whosonfirst.org/404/227/475/404227475.geojson"", ""label"": ""data.whosonfirst.org/404/227/475/404227475.geojson""}]" spatialite:importing-shapefiles-into-spatialite,spatialite,importing-shapefiles-into-spatialite,Importing shapefiles into SpatiaLite,"The shapefile format is a common format for distributing geospatial data. You can use the spatialite command-line tool to create a new database table from a shapefile. Try it now with the North America shapefile available from the University of North Carolina Global River Database project. Download the file and unzip it (this will create files called narivs.dbf , narivs.prj , narivs.shp and narivs.shx in the current directory), then run the following: spatialite rivers-database.db SpatiaLite version ..: 4.3.0a Supported Extensions: ... spatialite> .loadshp narivs rivers CP1252 23032 ======== Loading shapefile at 'narivs' into SQLite table 'rivers' ... Inserted 467973 rows into 'rivers' from SHAPEFILE This will load the data from the narivs shapefile into a new database table called rivers . Exit out of spatialite (using Ctrl+D ) and run Datasette against your new database like this: datasette rivers-database.db \ --load-extension=/usr/local/lib/mod_spatialite.dylib If you browse to http://localhost:8001/rivers-database/rivers you will see the new table... but the Geometry column will contain unreadable binary data (SpatiaLite uses a custom format based on WKB ). The easiest way to turn this into semi-readable data is to use the SpatiaLite AsGeoJSON function. Try the following using the SQL query interface at http://localhost:8001/rivers-database : select *, AsGeoJSON(Geometry) from rivers limit 10; This will give you back an additional column of GeoJSON. You can copy and paste GeoJSON from this column into the debugging tool at geojson.io to visualize it on a map. To see a more interesting example, try ordering the records with the longest geometry first. Since there are 467,000 rows in the table you will first need to increase the SQL time limit imposed by Datasette: datasette rivers-database.db \ --load-extension=/usr/local/lib/mod_spatialite.dylib \ --setting sql_time_limit_ms 10000 Now try the following query: select *, AsGeoJSON(Geometry) from rivers order by length(Geometry) desc limit 10;","[""SpatiaLite""]","[{""href"": ""https://en.wikipedia.org/wiki/Shapefile"", ""label"": ""shapefile format""}, {""href"": ""http://gaia.geosci.unc.edu/rivers/"", ""label"": ""Global River Database""}, {""href"": ""https://www.gaia-gis.it/gaia-sins/BLOB-Geometry.html"", ""label"": ""a custom format based on WKB""}, {""href"": ""https://geojson.io/"", ""label"": ""geojson.io""}]" spatialite:installing-spatialite-on-linux,spatialite,installing-spatialite-on-linux,Installing SpatiaLite on Linux,"SpatiaLite is packaged for most Linux distributions. apt install spatialite-bin libsqlite3-mod-spatialite Depending on your distribution, you should be able to run Datasette something like this: datasette --load-extension=/usr/lib/x86_64-linux-gnu/mod_spatialite.so If you are unsure of the location of the module, try running locate mod_spatialite and see what comes back.","[""SpatiaLite"", ""Installation""]",[] spatialite:installing-spatialite-on-os-x,spatialite,installing-spatialite-on-os-x,Installing SpatiaLite on OS X,"The easiest way to install SpatiaLite on OS X is to use Homebrew . brew update brew install spatialite-tools This will install the spatialite command-line tool and the mod_spatialite dynamic library. You can now run Datasette like so: datasette --load-extension=spatialite","[""SpatiaLite"", ""Installation""]","[{""href"": ""https://brew.sh/"", ""label"": ""Homebrew""}]" spatialite:making-use-of-a-spatial-index,spatialite,making-use-of-a-spatial-index,Making use of a spatial index,"SpatiaLite spatial indexes are R*Trees. They allow you to run efficient bounding box queries using a sub-select, with a similar pattern to that used for Searches using custom SQL . In the above example, the resulting index will be called idx_museums_point_geom . This takes the form of a SQLite virtual table. You can inspect its contents using the following query: select * from idx_museums_point_geom limit 10; Here's a live example: timezones-api.datasette.io/timezones/idx_timezones_Geometry pkid xmin xmax ymin ymax 1 -8.601725578308105 -2.4930307865142822 4.162120819091797 10.74019718170166 2 -3.2607860565185547 1.27329421043396 4.539252281188965 11.174856185913086 3 32.997581481933594 47.98238754272461 3.3974475860595703 14.894054412841797 4 -8.66890811920166 11.997337341308594 18.9681453704834 37.296207427978516 5 36.43336486816406 43.300174713134766 12.354820251464844 18.070993423461914 You can now construct efficient bounding box queries that will make use of the index like this: select * from museums where museums.rowid in ( SELECT pkid FROM idx_museums_point_geom -- left-hand-edge of point > left-hand-edge of bbox (minx) where xmin > :bbox_minx -- right-hand-edge of point < right-hand-edge of bbox (maxx) and xmax < :bbox_maxx -- bottom-edge of point > bottom-edge of bbox (miny) and ymin > :bbox_miny -- top-edge of point < top-edge of bbox (maxy) and ymax < :bbox_maxy ); Spatial indexes can be created against polygon columns as well as point columns, in which case they will represent the minimum bounding rectangle of that polygon. This is useful for accelerating within queries, as seen in the Timezones API example.","[""SpatiaLite""]","[{""href"": ""https://timezones-api.datasette.io/timezones/idx_timezones_Geometry"", ""label"": ""timezones-api.datasette.io/timezones/idx_timezones_Geometry""}]" spatialite:querying-polygons-using-within,spatialite,querying-polygons-using-within,Querying polygons using within(),"The within() SQL function can be used to check if a point is within a geometry: select name from places where within(GeomFromText('POINT(-3.1724366 51.4704448)'), places.geom); The GeomFromText() function takes a string of well-known text. Note that the order used here is longitude then latitude . To run that same within() query in a way that benefits from the spatial index, use the following: select name from places where within(GeomFromText('POINT(-3.1724366 51.4704448)'), places.geom) and rowid in ( SELECT pkid FROM idx_places_geom where xmin < -3.1724366 and xmax > -3.1724366 and ymin < 51.4704448 and ymax > 51.4704448 );","[""SpatiaLite""]",[] spatialite:spatial-indexing-latitude-longitude-columns,spatialite,spatial-indexing-latitude-longitude-columns,Spatial indexing latitude/longitude columns,"Here's a recipe for taking a table with existing latitude and longitude columns, adding a SpatiaLite POINT geometry column to that table, populating the new column and then populating a spatial index: import sqlite3 conn = sqlite3.connect(""museums.db"") # Lead the spatialite extension: conn.enable_load_extension(True) conn.load_extension(""/usr/local/lib/mod_spatialite.dylib"") # Initialize spatial metadata for this database: conn.execute(""select InitSpatialMetadata(1)"") # Add a geometry column called point_geom to our museums table: conn.execute( ""SELECT AddGeometryColumn('museums', 'point_geom', 4326, 'POINT', 2);"" ) # Now update that geometry column with the lat/lon points conn.execute( """""" UPDATE museums SET point_geom = GeomFromText('POINT('||""longitude""||' '||""latitude""||')',4326); """""" ) # Now add a spatial index to that column conn.execute( 'select CreateSpatialIndex(""museums"", ""point_geom"");' ) # If you don't commit your changes will not be persisted: conn.commit() conn.close()","[""SpatiaLite""]",[] spatialite:spatialite-installation,spatialite,spatialite-installation,Installation,,"[""SpatiaLite""]",[] spatialite:spatialite-warning,spatialite,spatialite-warning,Warning,"The SpatiaLite extension adds a large number of additional SQL functions , some of which are not be safe for untrusted users to execute: they may cause the Datasette server to crash. You should not expose a SpatiaLite-enabled Datasette instance to the public internet without taking extra measures to secure it against potentially harmful SQL queries. The following steps are recommended: Disable arbitrary SQL queries by untrusted users. See Controlling the ability to execute arbitrary SQL for ways to do this. The easiest is to start Datasette with the datasette --setting default_allow_sql off option. Define Canned queries with the SQL queries that use SpatiaLite functions that you want people to be able to execute. The Datasette SpatiaLite tutorial includes detailed instructions for running SpatiaLite safely using these techniques","[""SpatiaLite""]","[{""href"": ""https://www.gaia-gis.it/gaia-sins/spatialite-sql-5.0.1.html"", ""label"": ""a large number of additional SQL functions""}, {""href"": ""https://datasette.io/tutorials/spatialite"", ""label"": ""Datasette SpatiaLite tutorial""}]" sql_queries:canned-queries-json-api,sql_queries,canned-queries-json-api,JSON API for writable canned queries,"Writable canned queries can also be accessed using a JSON API. You can POST data to them using JSON, and you can request that their response is returned to you as JSON. To submit JSON to a writable canned query, encode key/value parameters as a JSON document: POST /mydatabase/add_message {""message"": ""Message goes here""} You can also continue to submit data using regular form encoding, like so: POST /mydatabase/add_message message=Message+goes+here There are three options for specifying that you would like the response to your request to return JSON data, as opposed to an HTTP redirect to another page. Set an Accept: application/json header on your request Include ?_json=1 in the URL that you POST to Include ""_json"": 1 in your JSON body, or &_json=1 in your form encoded body The JSON response will look like this: { ""ok"": true, ""message"": ""Query executed, 1 row affected"", ""redirect"": ""/data/add_name"" } The ""message"" and ""redirect"" values here will take into account on_success_message , on_success_message_sql , on_success_redirect , on_error_message and on_error_redirect , if they have been set.","[""Running SQL queries"", ""Canned queries""]",[] sql_queries:canned-queries-magic-parameters,sql_queries,canned-queries-magic-parameters,Magic parameters,"Named parameters that start with an underscore are special: they can be used to automatically add values created by Datasette that are not contained in the incoming form fields or query string. These magic parameters are only supported for canned queries: to avoid security issues (such as queries that extract the user's private cookies) they are not available to SQL that is executed by the user as a custom SQL query. Available magic parameters are: _actor_* - e.g. _actor_id , _actor_name Fields from the currently authenticated Actors . _header_* - e.g. _header_user_agent Header from the incoming HTTP request. The key should be in lower case and with hyphens converted to underscores e.g. _header_user_agent or _header_accept_language . _cookie_* - e.g. _cookie_lang The value of the incoming cookie of that name. _now_epoch The number of seconds since the Unix epoch. _now_date_utc The date in UTC, e.g. 2020-06-01 _now_datetime_utc The ISO 8601 datetime in UTC, e.g. 2020-06-24T18:01:07Z _random_chars_* - e.g. _random_chars_128 A random string of characters of the specified length. Here's an example configuration that adds a message from the authenticated user, storing various pieces of additional metadata using magic parameters: [[[cog config_example(cog, """""" databases: mydatabase: queries: add_message: allow: id: ""*"" sql: |- INSERT INTO messages ( user_id, message, datetime ) VALUES ( :_actor_id, :message, :_now_datetime_utc ) write: true """""") ]]] [[[end]]] The form presented at /mydatabase/add_message will have just a field for message - the other parameters will be populated by the magic parameter mechanism. Additional custom magic parameters can be added by plugins using the register_magic_parameters(datasette) hook.","[""Running SQL queries"", ""Canned queries""]",[] sql_queries:canned-queries-named-parameters,sql_queries,canned-queries-named-parameters,Canned query parameters,"Canned queries support named parameters, so if you include those in the SQL you will then be able to enter them using the form fields on the canned query page or by adding them to the URL. This means canned queries can be used to create custom JSON APIs based on a carefully designed SQL statement. Here's an example of a canned query with a named parameter: select neighborhood, facet_cities.name, state from facetable join facet_cities on facetable.city_id = facet_cities.id where neighborhood like '%' || :text || '%' order by neighborhood; In the canned query configuration looks like this: [[[cog config_example(cog, """""" databases: fixtures: queries: neighborhood_search: title: Search neighborhoods sql: |- select neighborhood, facet_cities.name, state from facetable join facet_cities on facetable.city_id = facet_cities.id where neighborhood like '%' || :text || '%' order by neighborhood """""") ]]] [[[end]]] Note that we are using SQLite string concatenation here - the || operator - to add wildcard % characters to the string provided by the user. You can try this canned query out here: https://latest.datasette.io/fixtures/neighborhood_search?text=town In this example the :text named parameter is automatically extracted from the query using a regular expression. You can alternatively provide an explicit list of named parameters using the ""params"" key, like this: [[[cog config_example(cog, """""" databases: fixtures: queries: neighborhood_search: title: Search neighborhoods params: - text sql: |- select neighborhood, facet_cities.name, state from facetable join facet_cities on facetable.city_id = facet_cities.id where neighborhood like '%' || :text || '%' order by neighborhood """""") ]]] [[[end]]]","[""Running SQL queries"", ""Canned queries""]","[{""href"": ""https://latest.datasette.io/fixtures/neighborhood_search?text=town"", ""label"": ""https://latest.datasette.io/fixtures/neighborhood_search?text=town""}]" sql_queries:canned-queries-options,sql_queries,canned-queries-options,Additional canned query options,Additional options can be specified for canned queries in the YAML or JSON configuration.,"[""Running SQL queries"", ""Canned queries""]",[] sql_queries:canned-queries-writable,sql_queries,canned-queries-writable,Writable canned queries,"Canned queries by default are read-only. You can use the ""write"": true key to indicate that a canned query can write to the database. See Access to specific canned queries for details on how to add permission checks to canned queries, using the ""allow"" key. [[[cog config_example(cog, { ""databases"": { ""mydatabase"": { ""queries"": { ""add_name"": { ""sql"": ""INSERT INTO names (name) VALUES (:name)"", ""write"": True } } } } }) ]]] [[[end]]] This configuration will create a page at /mydatabase/add_name displaying a form with a name field. Submitting that form will execute the configured INSERT query. You can customize how Datasette represents success and errors using the following optional properties: on_success_message - the message shown when a query is successful on_success_message_sql - alternative to on_success_message : a SQL query that should be executed to generate the message on_success_redirect - the path or URL the user is redirected to on success on_error_message - the message shown when a query throws an error on_error_redirect - the path or URL the user is redirected to on error For example: [[[cog config_example(cog, { ""databases"": { ""mydatabase"": { ""queries"": { ""add_name"": { ""sql"": ""INSERT INTO names (name) VALUES (:name)"", ""params"": [""name""], ""write"": True, ""on_success_message_sql"": ""select 'Name inserted: ' || :name"", ""on_success_redirect"": ""/mydatabase/names"", ""on_error_message"": ""Name insert failed"", ""on_error_redirect"": ""/mydatabase"", } } } } }) ]]] [[[end]]] You can use ""params"" to explicitly list the named parameters that should be displayed as form fields - otherwise they will be automatically detected. ""params"" is not necessary in the above example, since without it ""name"" would be automatically detected from the query. You can pre-populate form fields when the page first loads using a query string, e.g. /mydatabase/add_name?name=Prepopulated . The user will have to submit the form to execute the query. If you specify a query in ""on_success_message_sql"" , that query will be executed after the main query. The first column of the first row return by that query will be displayed as a success message. Named parameters from the main query will be made available to the success message query as well.","[""Running SQL queries"", ""Canned queries""]",[] sql_queries:fragment,sql_queries,fragment,fragment,"Some plugins, such as datasette-vega , can be configured by including additional data in the fragment hash of the URL - the bit that comes after a # symbol. You can set a default fragment hash that will be included in the link to the canned query from the database index page using the ""fragment"" key. This example demonstrates both fragment and hide_sql : [[[cog config_example(cog, """""" databases: fixtures: queries: neighborhood_search: fragment: fragment-goes-here hide_sql: true sql: |- select neighborhood, facet_cities.name, state from facetable join facet_cities on facetable.city_id = facet_cities.id where neighborhood like '%' || :text || '%' order by neighborhood; """""") ]]] [[[end]]] See here for a demo of this in action.","[""Running SQL queries"", ""Canned queries"", ""Additional canned query options""]","[{""href"": ""https://github.com/simonw/datasette-vega"", ""label"": ""datasette-vega""}, {""href"": ""https://latest.datasette.io/fixtures#queries"", ""label"": ""See here""}]" sql_queries:hide-sql,sql_queries,hide-sql,hide_sql,"Canned queries default to displaying their SQL query at the top of the page. If the query is extremely long you may want to hide it by default, with a ""show"" link that can be used to make it visible. Add the ""hide_sql"": true option to hide the SQL query by default.","[""Running SQL queries"", ""Canned queries"", ""Additional canned query options""]",[] sql_queries:id1,sql_queries,id1,Canned queries,"As an alternative to adding views to your database, you can define canned queries inside your datasette.yaml file. Here's an example: [[[cog from metadata_doc import config_example, config_example config_example(cog, { ""databases"": { ""sf-trees"": { ""queries"": { ""just_species"": { ""sql"": ""select qSpecies from Street_Tree_List"" } } } } }) ]]] [[[end]]] Then run Datasette like this: datasette sf-trees.db -m metadata.json Each canned query will be listed on the database index page, and will also get its own URL at: /database-name/canned-query-name For the above example, that URL would be: /sf-trees/just_species You can optionally include ""title"" and ""description"" keys to show a title and description on the canned query page. As with regular table metadata you can alternatively specify ""description_html"" to have your description rendered as HTML (rather than having HTML special characters escaped).","[""Running SQL queries""]",[] sql_queries:id2,sql_queries,id2,Pagination,"Datasette's default table pagination is designed to be extremely efficient. SQL OFFSET/LIMIT pagination can have a significant performance penalty once you get into multiple thousands of rows, as each page still requires the database to scan through every preceding row to find the correct offset. When paginating through tables, Datasette instead orders the rows in the table by their primary key and performs a WHERE clause against the last seen primary key for the previous page. For example: select rowid, * from Tree_List where rowid > 200 order by rowid limit 101 This represents page three for this particular table, with a page size of 100. Note that we request 101 items in the limit clause rather than 100. This allows us to detect if we are on the last page of the results: if the query returns less than 101 rows we know we have reached the end of the pagination set. Datasette will only return the first 100 rows - the 101st is used purely to detect if there should be another page. Since the where clause acts against the index on the primary key, the query is extremely fast even for records that are a long way into the overall pagination set.","[""Running SQL queries""]",[] sql_queries:id3,sql_queries,id3,Cross-database queries,"SQLite has the ability to run queries that join across multiple databases. Up to ten databases can be attached to a single SQLite connection and queried together. Datasette can execute joins across multiple databases if it is started with the --crossdb option: datasette fixtures.db extra_database.db --crossdb If it is started in this way, the /_memory page can be used to execute queries that join across multiple databases. References to tables in attached databases should be preceded by the database name and a period. For example, this query will show a list of tables across both of the above databases: select 'fixtures' as database, * from [fixtures].sqlite_master union select 'extra_database' as database, * from [extra_database].sqlite_master Try that out here .","[""Running SQL queries""]","[{""href"": ""https://latest.datasette.io/_memory?sql=select%0D%0A++%27fixtures%27+as+database%2C+*%0D%0Afrom%0D%0A++%5Bfixtures%5D.sqlite_master%0D%0Aunion%0D%0Aselect%0D%0A++%27extra_database%27+as+database%2C+*%0D%0Afrom%0D%0A++%5Bextra_database%5D.sqlite_master"", ""label"": ""Try that out here""}]" sql_queries:sql,sql_queries,sql,Running SQL queries,"Datasette treats SQLite database files as read-only and immutable. This means it is not possible to execute INSERT or UPDATE statements using Datasette, which allows us to expose SELECT statements to the outside world without needing to worry about SQL injection attacks. The easiest way to execute custom SQL against Datasette is through the web UI. The database index page includes a SQL editor that lets you run any SELECT query you like. You can also construct queries using the filter interface on the tables page, then click ""View and edit SQL"" to open that query in the custom SQL editor. Note that this interface is only available if the execute-sql permission is allowed. See Controlling the ability to execute arbitrary SQL . Any Datasette SQL query is reflected in the URL of the page, allowing you to bookmark them, share them with others and navigate through previous queries using your browser back button. You can also retrieve the results of any query as JSON by adding .json to the base URL.",[],[] sql_queries:sql-parameters,sql_queries,sql-parameters,Named parameters,"Datasette has special support for SQLite named parameters. Consider a SQL query like this: select * from Street_Tree_List where ""PermitNotes"" like :notes and ""qSpecies"" = :species If you execute this query using the custom query editor, Datasette will extract the two named parameters and use them to construct form fields for you to provide values. You can also provide values for these fields by constructing a URL: /mydatabase?sql=select...&species=44 SQLite string escaping rules will be applied to values passed using named parameters - they will be wrapped in quotes and their content will be correctly escaped. Values from named parameters are treated as SQLite strings. If you need to perform numeric comparisons on them you should cast them to an integer or float first using cast(:name as integer) or cast(:name as real) , for example: select * from Street_Tree_List where latitude > cast(:min_latitude as real) and latitude < cast(:max_latitude as real) Datasette disallows custom SQL queries containing the string PRAGMA (with a small number of exceptions ) as SQLite pragma statements can be used to change database settings at runtime. If you need to include the string ""pragma"" in a query you can do so safely using a named parameter.","[""Running SQL queries""]","[{""href"": ""https://github.com/simonw/datasette/issues/761"", ""label"": ""of exceptions""}]" sql_queries:sql-views,sql_queries,sql-views,Views,"If you want to bundle some pre-written SQL queries with your Datasette-hosted database you can do so in two ways. The first is to include SQL views in your database - Datasette will then list those views on your database index page. The quickest way to create views is with the SQLite command-line interface: sqlite3 sf-trees.db SQLite version 3.19.3 2017-06-27 16:48:08 Enter "".help"" for usage hints. sqlite> CREATE VIEW demo_view AS select qSpecies from Street_Tree_List; <CTRL+D> You can also use the sqlite-utils tool to create a view : sqlite-utils create-view sf-trees.db demo_view ""select qSpecies from Street_Tree_List""","[""Running SQL queries""]","[{""href"": ""https://sqlite-utils.datasette.io/"", ""label"": ""sqlite-utils""}, {""href"": ""https://sqlite-utils.datasette.io/en/stable/cli.html#creating-views"", ""label"": ""create a view""}]" testing_plugins:id1,testing_plugins,id1,Testing plugins,"We recommend using pytest to write automated tests for your plugins. If you use the template described in Starting an installable plugin using cookiecutter your plugin will start with a single test in your tests/ directory that looks like this: from datasette.app import Datasette import pytest @pytest.mark.asyncio async def test_plugin_is_installed(): datasette = Datasette(memory=True) response = await datasette.client.get(""/-/plugins.json"") assert response.status_code == 200 installed_plugins = {p[""name""] for p in response.json()} assert ( ""datasette-plugin-template-demo"" in installed_plugins ) This test uses the datasette.client object to exercise a test instance of Datasette. datasette.client is a wrapper around the HTTPX Python library which can imitate HTTP requests using ASGI. This is the recommended way to write tests against a Datasette instance. This test also uses the pytest-asyncio package to add support for async def test functions running under pytest. You can install these packages like so: pip install pytest pytest-asyncio If you are building an installable package you can add them as test dependencies to your setup.py module like this: setup( name=""datasette-my-plugin"", # ... extras_require={""test"": [""pytest"", ""pytest-asyncio""]}, tests_require=[""datasette-my-plugin[test]""], ) You can then install the test dependencies like so: pip install -e '.[test]' Then run the tests using pytest like so: pytest",[],"[{""href"": ""https://docs.pytest.org/"", ""label"": ""pytest""}, {""href"": ""https://www.python-httpx.org/"", ""label"": ""HTTPX""}, {""href"": ""https://pypi.org/project/pytest-asyncio/"", ""label"": ""pytest-asyncio""}]" testing_plugins:testing-datasette-client,testing_plugins,testing-datasette-client,Using datasette.client in tests,"The datasette.client mechanism is designed for use in tests. It provides access to a pre-configured HTTPX async client instance that can make GET, POST and other HTTP requests against a Datasette instance from inside a test. A simple test looks like this: @pytest.mark.asyncio async def test_homepage(): ds = Datasette(memory=True) response = await ds.client.get(""/"") html = response.text assert ""<h1>"" in html Or for a JSON API: @pytest.mark.asyncio async def test_actor_is_null(): ds = Datasette(memory=True) response = await ds.client.get(""/-/actor.json"") assert response.json() == {""actor"": None} To make requests as an authenticated actor, create a signed ds_cookie using the datasette.client.actor_cookie() helper function and pass it in cookies= like this: @pytest.mark.asyncio async def test_signed_cookie_actor(): ds = Datasette(memory=True) cookies = {""ds_actor"": ds.client.actor_cookie({""id"": ""root""})} response = await ds.client.get(""/-/actor.json"", cookies=cookies) assert response.json() == {""actor"": {""id"": ""root""}}","[""Testing plugins""]","[{""href"": ""https://www.python-httpx.org/async/"", ""label"": ""HTTPX async client""}]" testing_plugins:testing-plugins-datasette-test-instance,testing_plugins,testing-plugins-datasette-test-instance,Setting up a Datasette test instance,"The above example shows the easiest way to start writing tests against a Datasette instance: from datasette.app import Datasette import pytest @pytest.mark.asyncio async def test_plugin_is_installed(): datasette = Datasette(memory=True) response = await datasette.client.get(""/-/plugins.json"") assert response.status_code == 200 Creating a Datasette() instance like this as useful shortcut in tests, but there is one detail you need to be aware of. It's important to ensure that the async method .invoke_startup() is called on that instance. You can do that like this: datasette = Datasette(memory=True) await datasette.invoke_startup() This method registers any startup(datasette) or prepare_jinja2_environment(env, datasette) plugins that might themselves need to make async calls. If you are using await datasette.client.get() and similar methods then you don't need to worry about this - Datasette automatically calls invoke_startup() the first time it handles a request.","[""Testing plugins""]",[] testing_plugins:testing-plugins-fixtures,testing_plugins,testing-plugins-fixtures,Using pytest fixtures,"Pytest fixtures can be used to create initial testable objects which can then be used by multiple tests. A common pattern for Datasette plugins is to create a fixture which sets up a temporary test database and wraps it in a Datasette instance. Here's an example that uses the sqlite-utils library to populate a temporary test database. It also sets the title of that table using a simulated metadata.json configuration: from datasette.app import Datasette import pytest import sqlite_utils @pytest.fixture(scope=""session"") def datasette(tmp_path_factory): db_directory = tmp_path_factory.mktemp(""dbs"") db_path = db_directory / ""test.db"" db = sqlite_utils.Database(db_path) db[""dogs""].insert_all( [ {""id"": 1, ""name"": ""Cleo"", ""age"": 5}, {""id"": 2, ""name"": ""Pancakes"", ""age"": 4}, ], pk=""id"", ) datasette = Datasette( [db_path], metadata={ ""databases"": { ""test"": { ""tables"": { ""dogs"": {""title"": ""Some dogs""} } } } }, ) return datasette @pytest.mark.asyncio async def test_example_table_json(datasette): response = await datasette.client.get( ""/test/dogs.json?_shape=array"" ) assert response.status_code == 200 assert response.json() == [ {""id"": 1, ""name"": ""Cleo"", ""age"": 5}, {""id"": 2, ""name"": ""Pancakes"", ""age"": 4}, ] @pytest.mark.asyncio async def test_example_table_html(datasette): response = await datasette.client.get(""/test/dogs"") assert "">Some dogs</h1>"" in response.text Here the datasette() function defines the fixture, which is than automatically passed to the two test functions based on pytest automatically matching their datasette function parameters. The @pytest.fixture(scope=""session"") line here ensures the fixture is reused for the full pytest execution session. This means that the temporary database file will be created once and reused for each test. If you want to create that test database repeatedly for every individual test function, write the fixture function like this instead. You may want to do this if your plugin modifies the database contents in some way: @pytest.fixture def datasette(tmp_path_factory): # This fixture will be executed repeatedly for every test ...","[""Testing plugins""]","[{""href"": ""https://docs.pytest.org/en/stable/fixture.html"", ""label"": ""Pytest fixtures""}, {""href"": ""https://sqlite-utils.datasette.io/en/stable/python-api.html"", ""label"": ""sqlite-utils library""}]" testing_plugins:testing-plugins-pdb,testing_plugins,testing-plugins-pdb,Using pdb for errors thrown inside Datasette,"If an exception occurs within Datasette itself during a test, the response returned to your plugin will have a response.status_code value of 500. You can add pdb=True to the Datasette constructor to drop into a Python debugger session inside your test run instead of getting back a 500 response code. This is equivalent to running the datasette command-line tool with the --pdb option. Here's what that looks like in a test function: def test_that_opens_the_debugger_or_errors(): ds = Datasette([db_path], pdb=True) response = await ds.client.get(""/"") If you use this pattern you will need to run pytest with the -s option to avoid capturing stdin/stdout in order to interact with the debugger prompt.","[""Testing plugins""]",[] testing_plugins:testing-plugins-pytest-httpx,testing_plugins,testing-plugins-pytest-httpx,Testing outbound HTTP calls with pytest-httpx,"If your plugin makes outbound HTTP calls - for example datasette-auth-github or datasette-import-table - you may need to mock those HTTP requests in your tests. The pytest-httpx package is a useful library for mocking calls. It can be tricky to use with Datasette though since it mocks all HTTPX requests, and Datasette's own testing mechanism uses HTTPX internally. To avoid breaking your tests, you can return [""localhost""] from the non_mocked_hosts() fixture. As an example, here's a very simple plugin which executes an HTTP response and returns the resulting content: from datasette import hookimpl from datasette.utils.asgi import Response import httpx @hookimpl def register_routes(): return [ (r""^/-/fetch-url$"", fetch_url), ] async def fetch_url(datasette, request): if request.method == ""GET"": return Response.html( """""" <form action=""/-/fetch-url"" method=""post""> <input type=""hidden"" name=""csrftoken"" value=""{}""> <input name=""url""><input type=""submit""> </form>"""""".format( request.scope[""csrftoken""]() ) ) vars = await request.post_vars() url = vars[""url""] return Response.text(httpx.get(url).text) Here's a test for that plugin that mocks the HTTPX outbound request: from datasette.app import Datasette import pytest @pytest.fixture def non_mocked_hosts(): # This ensures httpx-mock will not affect Datasette's own # httpx calls made in the tests by datasette.client: return [""localhost""] async def test_outbound_http_call(httpx_mock): httpx_mock.add_response( url=""https://www.example.com/"", text=""Hello world"", ) datasette = Datasette([], memory=True) response = await datasette.client.post( ""/-/fetch-url"", data={""url"": ""https://www.example.com/""}, ) assert response.text == ""Hello world"" outbound_request = httpx_mock.get_request() assert ( outbound_request.url == ""https://www.example.com/"" )","[""Testing plugins""]","[{""href"": ""https://pypi.org/project/pytest-httpx/"", ""label"": ""pytest-httpx""}]" testing_plugins:testing-plugins-register-in-test,testing_plugins,testing-plugins-register-in-test,Registering a plugin for the duration of a test,"When writing tests for plugins you may find it useful to register a test plugin just for the duration of a single test. You can do this using pm.register() and pm.unregister() like this: from datasette import hookimpl from datasette.app import Datasette from datasette.plugins import pm import pytest @pytest.mark.asyncio async def test_using_test_plugin(): class TestPlugin: __name__ = ""TestPlugin"" # Use hookimpl and method names to register hooks @hookimpl def register_routes(self): return [ (r""^/error$"", lambda: 1 / 0), ] pm.register(TestPlugin(), name=""undo"") try: # The test implementation goes here datasette = Datasette() response = await datasette.client.get(""/error"") assert response.status_code == 500 finally: pm.unregister(name=""undo"") To reuse the same temporary plugin in multiple tests, you can register it inside a fixture in your conftest.py file like this: from datasette import hookimpl from datasette.app import Datasette from datasette.plugins import pm import pytest import pytest_asyncio @pytest_asyncio.fixture async def datasette_with_plugin(): class TestPlugin: __name__ = ""TestPlugin"" @hookimpl def register_routes(self): return [ (r""^/error$"", lambda: 1 / 0), ] pm.register(TestPlugin(), name=""undo"") try: yield Datasette() finally: pm.unregister(name=""undo"") Note the yield statement here - this ensures that the finally: block that unregisters the plugin is executed only after the test function itself has completed. Then in a test: @pytest.mark.asyncio async def test_error(datasette_with_plugin): response = await datasette_with_plugin.client.get(""/error"") assert response.status_code == 500","[""Testing plugins""]",[] writing_plugins:id1,writing_plugins,id1,Writing plugins,"You can write one-off plugins that apply to just one Datasette instance, or you can write plugins which can be installed using pip and can be shipped to the Python Package Index ( PyPI ) for other people to install. Want to start by looking at an example? The Datasette plugins directory lists more than 90 open source plugins with code you can explore. The plugin hooks page includes links to example plugins for each of the documented hooks.",[],"[{""href"": ""https://pypi.org/"", ""label"": ""PyPI""}, {""href"": ""https://datasette.io/plugins"", ""label"": ""Datasette plugins directory""}]" writing_plugins:writing-plugins-building-urls,writing_plugins,writing-plugins-building-urls,Building URLs within plugins,"Plugins that define their own custom user interface elements may need to link to other pages within Datasette. This can be a bit tricky if the Datasette instance is using the base_url configuration setting to run behind a proxy, since that can cause Datasette's URLs to include an additional prefix. The datasette.urls object provides internal methods for correctly generating URLs to different pages within Datasette, taking any base_url configuration into account. This object is exposed in templates as the urls variable, which can be used like this: Back to the <a href=""{{ urls.instance() }}"">Homepage</a> See datasette.urls for full details on this object.","[""Writing plugins""]",[] writing_plugins:writing-plugins-configuration,writing_plugins,writing-plugins-configuration,Writing plugins that accept configuration,"When you are writing plugins, you can access plugin configuration like this using the datasette plugin_config() method. If you know you need plugin configuration for a specific table, you can access it like this: plugin_config = datasette.plugin_config( ""datasette-cluster-map"", database=""sf-trees"", table=""Street_Tree_List"" ) This will return the {""latitude_column"": ""lat"", ""longitude_column"": ""lng""} in the above example. If there is no configuration for that plugin, the method will return None . If it cannot find the requested configuration at the table layer, it will fall back to the database layer and then the root layer. For example, a user may have set the plugin configuration option inside datasette.yaml like so: [[[cog from metadata_doc import metadata_example metadata_example(cog, { ""databases"": { ""sf-trees"": { ""plugins"": { ""datasette-cluster-map"": { ""latitude_column"": ""xlat"", ""longitude_column"": ""xlng"" } } } } }) ]]] [[[end]]] In this case, the above code would return that configuration for ANY table within the sf-trees database. The plugin configuration could also be set at the top level of datasette.yaml : [[[cog metadata_example(cog, { ""plugins"": { ""datasette-cluster-map"": { ""latitude_column"": ""xlat"", ""longitude_column"": ""xlng"" } } }) ]]] [[[end]]] Now that datasette-cluster-map plugin configuration will apply to every table in every database.","[""Writing plugins""]",[] writing_plugins:writing-plugins-cookiecutter,writing_plugins,writing-plugins-cookiecutter,Starting an installable plugin using cookiecutter,"Plugins that can be installed should be written as Python packages using a setup.py file. The quickest way to start writing one an installable plugin is to use the datasette-plugin cookiecutter template. This creates a new plugin structure for you complete with an example test and GitHub Actions workflows for testing and publishing your plugin. Install cookiecutter and then run this command to start building a plugin using the template: cookiecutter gh:simonw/datasette-plugin Read a cookiecutter template for writing Datasette plugins for more information about this template.","[""Writing plugins""]","[{""href"": ""https://github.com/simonw/datasette-plugin"", ""label"": ""datasette-plugin""}, {""href"": ""https://cookiecutter.readthedocs.io/en/stable/installation.html"", ""label"": ""Install cookiecutter""}, {""href"": ""https://simonwillison.net/2020/Jun/20/cookiecutter-plugins/"", ""label"": ""a cookiecutter template for writing Datasette plugins""}]" writing_plugins:writing-plugins-custom-templates,writing_plugins,writing-plugins-custom-templates,Custom templates,"If your plugin has a templates/ directory, Datasette will attempt to load templates from that directory before it uses its own default templates. The priority order for template loading is: templates from the --template-dir argument, if specified templates from the templates/ directory in any installed plugins default templates that ship with Datasette See Custom pages and templates for more details on how to write custom templates, including which filenames to use to customize which parts of the Datasette UI. Templates should be bundled for distribution using the same package_data mechanism in setup.py described for static assets above, for example: package_data = ( { ""datasette_plugin_name"": [ ""templates/my_template.html"", ], }, ) You can also use wildcards here such as templates/*.html . See datasette-edit-schema for an example of this pattern.","[""Writing plugins""]","[{""href"": ""https://github.com/simonw/datasette-edit-schema"", ""label"": ""datasette-edit-schema""}]" writing_plugins:writing-plugins-designing-urls,writing_plugins,writing-plugins-designing-urls,Designing URLs for your plugin,"You can register new URL routes within Datasette using the register_routes(datasette) plugin hook. Datasette's default URLs include these: /dbname - database page /dbname/tablename - table page /dbname/tablename/pk - row page See Pages and API endpoints and Introspection for more default URL routes. To avoid accidentally conflicting with a database file that may be loaded into Datasette, plugins should register URLs using a /-/ prefix. For example, if your plugin adds a new interface for uploading Excel files you might register a URL route like this one: /-/upload-excel Try to avoid registering URLs that clash with other plugins that your users might have installed. There is no central repository of reserved URL paths (yet) but you can review existing plugins by browsing the plugins directory . If your plugin includes functionality that relates to a specific database you could also register a URL route like this: /dbname/-/upload-excel Or for a specific table like this: /dbname/tablename/-/modify-table-schema Note that a row could have a primary key of - and this URL scheme will still work, because Datasette row pages do not ever have a trailing slash followed by additional path components.","[""Writing plugins""]","[{""href"": ""https://datasette.io/plugins"", ""label"": ""plugins directory""}]" writing_plugins:writing-plugins-extra-hooks,writing_plugins,writing-plugins-extra-hooks,Plugins that define new plugin hooks,"Plugins can define new plugin hooks that other plugins can use to further extend their functionality. datasette-graphql is one example of a plugin that does this. It defines a new hook called graphql_extra_fields , described here , which other plugins can use to define additional fields that should be included in the GraphQL schema. To define additional hooks, add a file to the plugin called datasette_your_plugin/hookspecs.py with content that looks like this: from pluggy import HookspecMarker hookspec = HookspecMarker(""datasette"") @hookspec def name_of_your_hook_goes_here(datasette): ""Description of your hook."" You should define your own hook name and arguments here, following the documentation for Pluggy specifications . Make sure to pick a name that is unlikely to clash with hooks provided by any other plugins. Then, to register your plugin hooks, add the following code to your datasette_your_plugin/__init__.py file: from datasette.plugins import pm from . import hookspecs pm.add_hookspecs(hookspecs) This will register your plugin hooks as part of the datasette plugin hook namespace. Within your plugin code you can trigger the hook using this pattern: from datasette.plugins import pm for ( plugin_return_value ) in pm.hook.name_of_your_hook_goes_here( datasette=datasette ): # Do something with plugin_return_value pass Other plugins will then be able to register their own implementations of your hook using this syntax: from datasette import hookimpl @hookimpl def name_of_your_hook_goes_here(datasette): return ""Response from this plugin hook"" These plugin implementations can accept 0 or more of the named arguments that you defined in your hook specification.","[""Writing plugins""]","[{""href"": ""https://github.com/simonw/datasette-graphql"", ""label"": ""datasette-graphql""}, {""href"": ""https://github.com/simonw/datasette-graphql/blob/main/README.md#adding-custom-fields-with-plugins"", ""label"": ""described here""}, {""href"": ""https://pluggy.readthedocs.io/en/stable/#specs"", ""label"": ""Pluggy specifications""}]" writing_plugins:writing-plugins-one-off,writing_plugins,writing-plugins-one-off,Writing one-off plugins,"The quickest way to start writing a plugin is to create a my_plugin.py file and drop it into your plugins/ directory. Here is an example plugin, which adds a new custom SQL function called hello_world() which takes no arguments and returns the string Hello world! . from datasette import hookimpl @hookimpl def prepare_connection(conn): conn.create_function( ""hello_world"", 0, lambda: ""Hello world!"" ) If you save this in plugins/my_plugin.py you can then start Datasette like this: datasette serve mydb.db --plugins-dir=plugins/ Now you can navigate to http://localhost:8001/mydb and run this SQL: select hello_world(); To see the output of your plugin.","[""Writing plugins""]","[{""href"": ""http://localhost:8001/mydb"", ""label"": ""http://localhost:8001/mydb""}]" writing_plugins:writing-plugins-packaging,writing_plugins,writing-plugins-packaging,Packaging a plugin,"Plugins can be packaged using Python setuptools. You can see an example of a packaged plugin at https://github.com/simonw/datasette-plugin-demos The example consists of two files: a setup.py file that defines the plugin: from setuptools import setup VERSION = ""0.1"" setup( name=""datasette-plugin-demos"", description=""Examples of plugins for Datasette"", author=""Simon Willison"", url=""https://github.com/simonw/datasette-plugin-demos"", license=""Apache License, Version 2.0"", version=VERSION, py_modules=[""datasette_plugin_demos""], entry_points={ ""datasette"": [ ""plugin_demos = datasette_plugin_demos"" ] }, install_requires=[""datasette""], ) And a Python module file, datasette_plugin_demos.py , that implements the plugin: from datasette import hookimpl import random @hookimpl def prepare_jinja2_environment(env): env.filters[""uppercase""] = lambda u: u.upper() @hookimpl def prepare_connection(conn): conn.create_function( ""random_integer"", 2, random.randint ) Having built a plugin in this way you can turn it into an installable package using the following command: python3 setup.py sdist This will create a .tar.gz file in the dist/ directory. You can then install your new plugin into a Datasette virtual environment or Docker container using pip : pip install datasette-plugin-demos-0.1.tar.gz To learn how to upload your plugin to PyPI for use by other people, read the PyPA guide to Packaging and distributing projects .","[""Writing plugins""]","[{""href"": ""https://github.com/simonw/datasette-plugin-demos"", ""label"": ""https://github.com/simonw/datasette-plugin-demos""}, {""href"": ""https://pypi.org/"", ""label"": ""PyPI""}, {""href"": ""https://packaging.python.org/tutorials/distributing-packages/"", ""label"": ""Packaging and distributing projects""}]" writing_plugins:writing-plugins-static-assets,writing_plugins,writing-plugins-static-assets,Static assets,"If your plugin has a static/ directory, Datasette will automatically configure itself to serve those static assets from the following path: /-/static-plugins/NAME_OF_PLUGIN_PACKAGE/yourfile.js Use the datasette.urls.static_plugins(plugin_name, path) method to generate URLs to that asset that take the base_url setting into account, see datasette.urls . To bundle the static assets for a plugin in the package that you publish to PyPI, add the following to the plugin's setup.py : package_data = ( { ""datasette_plugin_name"": [ ""static/plugin.js"", ], }, ) Where datasette_plugin_name is the name of the plugin package (note that it uses underscores, not hyphens) and static/plugin.js is the path within that package to the static file. datasette-cluster-map is a useful example of a plugin that includes packaged static assets in this way.","[""Writing plugins""]","[{""href"": ""https://github.com/simonw/datasette-cluster-map"", ""label"": ""datasette-cluster-map""}]" writing_plugins:writing-plugins-tracing,writing_plugins,writing-plugins-tracing,Tracing plugin hooks,"The DATASETTE_TRACE_PLUGINS environment variable turns on detailed tracing showing exactly which hooks are being run. This can be useful for understanding how Datasette is using your plugin. DATASETTE_TRACE_PLUGINS=1 datasette mydb.db Example output: actor_from_request: { 'datasette': <datasette.app.Datasette object at 0x100bc7220>, 'request': <asgi.Request method=""GET"" url=""http://127.0.0.1:4433/"">} Hook implementations: [ <HookImpl plugin_name='codespaces', plugin=<module 'datasette_codespaces' from '.../site-packages/datasette_codespaces/__init__.py'>>, <HookImpl plugin_name='datasette.actor_auth_cookie', plugin=<module 'datasette.actor_auth_cookie' from '.../datasette/datasette/actor_auth_cookie.py'>>, <HookImpl plugin_name='datasette.default_permissions', plugin=<module 'datasette.default_permissions' from '.../datasette/default_permissions.py'>>] Results: [{'id': 'root'}]","[""Writing plugins""]",[]