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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:id2 json_api id2 Table arguments The Datasette table view takes a number of special query string arguments. ["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… ["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-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: <https://latest.datasette.io/fixtures/sortable.json?_next=d%2Cv>; 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: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: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-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: <link rel="alternate" type="application/json+datasette" href="https://latest.datasette.io/fixtures/sortable.json"> 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-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 :… ["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"] []