id,page,ref,title,content,breadcrumbs,references changelog:id15,changelog,id15,Plugin hooks,"New plugin hook: handle_exception() , for custom handling of exceptions caught by Datasette. ( #1770 ) The render_cell() plugin hook is now also passed a row argument, representing the sqlite3.Row object that is being rendered. ( #1300 ) The configuration directory is now stored in datasette.config_dir , making it available to plugins. Thanks, Chris Amico. ( #1766 )","[""Changelog"", ""0.62 (2022-08-14)""]","[{""href"": ""https://github.com/simonw/datasette/issues/1770"", ""label"": ""#1770""}, {""href"": ""https://github.com/simonw/datasette/issues/1300"", ""label"": ""#1300""}, {""href"": ""https://github.com/simonw/datasette/pull/1766"", ""label"": ""#1766""}]" changelog:plugin-hooks,changelog,plugin-hooks,Plugin hooks,"New jinja2_environment_from_request(datasette, request, env) plugin hook, which can be used to customize the current Jinja environment based on the incoming request. This can be used to modify the template lookup path based on the incoming request hostname, among other things. ( #2225 ) New family of template slot plugin hooks : top_homepage , top_database , top_table , top_row , top_query , top_canned_query . Plugins can use these to provide additional HTML to be injected at the top of the corresponding pages. ( #1191 ) New track_event() mechanism for plugins to emit and receive events when certain events occur within Datasette. ( #2240 ) Plugins can register additional event classes using register_events(datasette) . They can then trigger those events with the datasette.track_event(event) internal method. Plugins can subscribe to notifications of events using the track_event(datasette, event) plugin hook. Datasette core now emits login , logout , create-token , create-table , drop-table , insert-rows , upsert-rows , update-row , delete-row events, documented here . New internal function for plugin authors: await db.execute_isolated_fn(fn) , for creating a new SQLite connection, executing code and then closing that connection, all while preventing other code from writing to that particular database. This connection will not have the prepare_connection() plugin hook executed against it, allowing plugins to perform actions that might otherwise be blocked by existing connection configuration. ( #2218 )","[""Changelog"", ""1.0a8 (2024-02-07)""]","[{""href"": ""https://github.com/simonw/datasette/issues/2225"", ""label"": ""#2225""}, {""href"": ""https://github.com/simonw/datasette/issues/1191"", ""label"": ""#1191""}, {""href"": ""https://github.com/simonw/datasette/issues/2240"", ""label"": ""#2240""}, {""href"": ""https://github.com/simonw/datasette/issues/2218"", ""label"": ""#2218""}]" 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""}]"