Planning Channels v4.0

🚨 Testing wanted: see the comment below 🚨

I’ve begun work on the next major version, which will be v4.0. I’m looking to release early-September 2022.

The main highlights will be:

• Removal of the old AsgiHandler, and related code. All of this now lives in Django, and you should be using that.
• Removal of support for ASGI v2 double-callables. Your apps should all be ASGI v3 single-callables by now.
• A move of the runserver command to Daphne, so that folks using other ASGI servers don’t have that import overhead to use Channels.
• And then various tidy-ups and other fixes that we’ve got time for.

The hope is this leaves Channels nice and tight as the Consumers, Channel Layer stuff, and not too much else. The use-case is: “I want to do Websockets, or lower-level ASGI with my Django app” It should be that we can evolve through point-releases for a while from now after this. 🤞

Matching updates to Daphne and channels_redis will come at the same time.

See the recent additions to Closed Pull Requests and the WIP CHANGELOG until I can draft the full release announcements for the details.

I’ve begun with the code changes. You’ll need to install the repos from main in order to test (e.g. the runserver move) Any feedback appreciated.

Next up, I want to go through the docs and tutorials and get those into place, then I’ll look at updating the packaging, and we’ll see where we’re at.

[carltongibson]

Great thanks @DmytroLitvinov.

I had a slight delay this week but am working on the releases and they’ll be out shortly. (It’s DjangoCon this week coming up so I should have a moment to sit down and do it at some point. 😜)

[carltongibson]

OK, I’ve released a beta 4.0.0b1, and there’s matching betas for Daphne and channels-redis too:

• https://pypi.org/project/channels/4.0.0b1/
• https://pypi.org/project/daphne/4.0.0b1/
• https://pypi.org/project/channels-redis/4.0.0b1/

Testing this is appreciated, particularly with the new optional daphne dependency:

pip install 'channels[daphne]==4.0.0b1'

… and adding daphne to INSTALLED_APPS for the runserver implementation:

    INSTALLED_APPS = [
        'daphne',
        ...
    ]

As well as running without Daphne, for those of you who wanted that.

Please see the above comment for the links to changes, and the closed PRs.

• The full release announcement and changelog tweaks are remaining to do.
• There’s updated docs at the latest version on RTD: https://channels.readthedocs.io/en/latest/

Goal now is to pick up any issues, knock off a few extras, and do final releases for ≈14th Sept.