2.1.2 Release Notes
===================

Channels 2.1.2 is another bugfix release in the 2.1 series.

Special thanks to people at the DjangoCon Europe sprints who helped out with
several of these fixes.


Major Changes
-------------

Session and authentication middleware has been overhauled to be non-blocking.
Previously, these middlewares potentially did database or session store access
in the synchronous ASGI constructor, meaning they would block the entire event
loop while doing so.

Instead, they have now been modified to add LazyObjects into the scope in the
places where the session or user will be, and then when the processing goes
through their asynchronous portion, those stores are accessed in a non-blocking
fashion.

This should be an un-noticeable change for end users, but if you see weird
behaviour or an unresolved LazyObject, let us know.


Bugfixes & Small Changes
------------------------

* AsyncHttpConsumer now has a disconnect() method you can override if you
  want to perform actions (such as leaving groups) when a long-running HTTP
  request disconnects.

* URL routing context now includes default arguments from the URLconf in the
  context's ``url_route`` key, alongside captured arguments/groups from the
  URL pattern.

* The FORCE_SCRIPT_NAME setting is now respected in ASGI mode, and lets you
  override where Django thinks the root URL of your application is mounted.

* ALLOWED_HOSTS is now set correctly during LiveServerTests, meaning you will
  no longer get ``400 Bad Request`` errors during these test runs.


Backwards Incompatible Changes
------------------------------

None.
