html_url,id,node_id,tag_name,target_commitish,name,draft,author,author_label,prerelease,created_at,published_at,body,repo,repo_label,reactions
https://github.com/simonw/datasette/releases/tag/0.45,28134124,MDc6UmVsZWFzZTI4MTM0MTI0,0.45,master,0.45,0,9599,simonw,0,2020-07-01T21:43:07Z,2020-07-01T21:46:07Z,"Magic parameters for canned queries, a log out feature, improved plugin documentation and four new plugin hooks.

### Magic parameters for canned queries

Canned queries now support [Magic parameters](https://docs.datasette.io/en/stable/sql_queries.html#canned-queries-magic-parameters), which can be used to insert or select automatically generated values. For example:
```sql
insert into logs
  (user_id, timestamp)
values
  (:_actor_id, :_now_datetime_utc)
```
This inserts the currently authenticated actor ID and the current datetime. ([#842](https://github.com/simonw/datasette/issues/842))

### Log out

The [ds_actor cookie](https://docs.datasette.io/en/stable/authentication.html#authentication-ds-actor) can be used by plugins (or by Datasette's [--root mechanism](https://docs.datasette.io/en/stable/authentication.html#authentication-root)) to authenticate users. The new `/-/logout` page provides a way to clear that cookie.

A ""Log out"" button now shows in the global navigation provided the user is authenticated using the `ds_actor` cookie. ([#840](https://github.com/simonw/datasette/issues/840))

### Better plugin documentation

The plugin documentation has been re-arranged into four sections, including a brand new section on testing plugins. ([#687](https://github.com/simonw/datasette/issues/687))

-   [Plugins](https://docs.datasette.io/en/stable/plugins.html#plugins) introduces Datasette's plugin system and describes how to install and configure plugins.
-   [Writing plugins](https://docs.datasette.io/en/stable/writing_plugins.html#writing-plugins) describes how to author plugins, from simple one-off plugins to packaged plugins that can be published to PyPI. It also describes how to start a plugin using the new [datasette-plugin](https://github.com/simonw/datasette-plugin) cookiecutter template.
-   [Plugin hooks](https://docs.datasette.io/en/stable/plugin_hooks.html#plugin-hooks) is a full list of detailed documentation for every Datasette plugin hook.
-   [Testing plugins](https://docs.datasette.io/en/stable/testing_plugins.html#testing-plugins) describes how to write tests for Datasette plugins, using [pytest](https://docs.pytest.org/) and [HTTPX](https://www.python-httpx.org/).

### New plugin hooks

-   [register_magic_parameters(datasette)](https://docs.datasette.io/en/stable/plugin_hooks.html#plugin-hook-register-magic-parameters) can be used to define new types of magic canned query parameters.
-   [startup(datasette)](https://docs.datasette.io/en/stable/plugin_hooks.html#plugin-hook-startup) can run custom code when Datasette first starts up. [datasette-init](https://github.com/simonw/datasette-init) is a new plugin that uses this hook to create database tables and views on startup if they have not yet been created. ([#834](https://github.com/simonw/datasette/issues/834))
-   [canned_queries(datasette, database, actor)](https://docs.datasette.io/en/stable/plugin_hooks.html#plugin-hook-canned-queries) lets plugins provide additional canned queries beyond those defined in Datasette's metadata. See [datasette-saved-queries](https://github.com/simonw/datasette-saved-queries) for an example of this hook in action. ([#852](https://github.com/simonw/datasette/issues/852))
-   [forbidden(datasette, request, message)](https://docs.datasette.io/en/stable/plugin_hooks.html#plugin-hook-forbidden) is a hook for customizing how Datasette responds to 403 forbidden errors. ([#812](https://github.com/simonw/datasette/issues/812))

### Smaller changes

-   Cascading view permissons - 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](https://github.com/simonw/datasette/issues/832))
-   CSRF protection no longer applies to `Authentication: Bearer token` requests or requests without cookies. ([#835](https://github.com/simonw/datasette/issues/835))
-   `datasette.add_message()` now works inside plugins. ([#864](https://github.com/simonw/datasette/issues/864))
-   Workaround for ""Too many open files"" error in test runs. ([#846](https://github.com/simonw/datasette/issues/846))
-   Respect existing `scope[""actor""]` if already set by ASGI middleware. ([#854](https://github.com/simonw/datasette/issues/854))
-   New process for shipping [Alpha and beta releases](https://docs.datasette.io/en/stable/contributing.html#contributing-alpha-beta). ([#807](https://github.com/simonw/datasette/issues/807))
-   `{{ csrftoken() }}` now works when plugins render a template using `datasette.render_template(..., request=request)`. ([#863](https://github.com/simonw/datasette/issues/863))
-   Datasette now creates a single [Request object](https://docs.datasette.io/en/stable/internals.html#internals-request) and uses it throughout the lifetime of the current HTTP request. ([#870](https://github.com/simonw/datasette/issues/870))",107914493,datasette,
https://github.com/simonw/datasette/releases/tag/0.45a5,28097766,MDc6UmVsZWFzZTI4MDk3NzY2,0.45a5,master,0.45a5,0,9599,simonw,1,2020-07-01T04:25:35Z,2020-07-01T04:27:08Z,,107914493,datasette,