DEP 84: Rejuvenate form media

[thibaudcolas]

Draft, not ready for review yet

Read the DEP as HTML

For context, see the forum thread: Rejuvenating vs deprecating Form.Media.

[matthiask]

I think introducing the JS class from django-js-asset into Django would be worthwile; probably a few parts of the admin should be refactored to take advantage of this? It's very stable, nothing has changed since the beginning of 2022.

[matthiask]

I think that's a very complete list. As I already said on the forum thread, I think that the frontend tooling space is still moving so quickly that it's hard to know which tools may or may not be useful in a few years time. When I think about Django and it's stability I have a horizon of several years always, with frontend tooling that's just not the case. If we had more fellows and/or more people which are paid to work on Django it could be a good idea. Even though I'm actually a (p)react and web/rspack fan I think it's a good idea for Django to stay in the backend world.

So, I think there's a lot of value in trying to support CSP (that was one of the motivations for django-js-asset, see https://406.ch/writing/django-admin-apps-and-content-security-policy-compliance/ ), supporting additional arbitrary attributes on <script> tags etc. but that's it.

I'm not sure I understand the resource ordering thing. Django already supports relatively complex dependencies (at least since https://code.djangoproject.com/ticket/30153). Of course that doesn't do anything about the initial page loading performance, but then you're already in the area of bundlers again.

[thibaudcolas]

From my perspective everything on that list has already proven its usefulness quite clearly! Additional attributes on <script> would be really useful but that feels to me like a rejuvenation of the Media API to bring it to 2014 standards rather than 2024.

[lb-]

Should we also be adding anything about Django providing polyfills?

As in

Opt in set of polyfills to support some/all of the above via pre-approved CDNs. Import maps, ESM, Web Components being the main ones. 

This is something the Rails approach did I believe, to allow for a 'simple' cross browser support approach where developers didn't have to think about what to include.

[claudep]

I think introducing the JS class from django-js-asset into Django would be worthwile; probably a few parts of the admin should be refactored to take advantage of this? It's very stable, nothing has changed since the beginning of 2022.

Big +1. When I pushed for django/django@4c76ffc2d6c77, it was my hope that at some point we could agree on some class-based JS/CSS objects (see the example in test_media.py).

[matthiask]

Hi @thibaudcolas

Is there anything I can do to move this forward?

[thibaudcolas]

@matthiask would you be up for writing the "new attributes for <script> tags, and why we need them" side of the DEP? Then we can get things moving with this, and from my side I can focus on the research I want to do for other requirements for merging of form widgets’ dependencies.

[matthiask]

@thibaudcolas I have been thinking about this at least once every week. Sorry for not responding sooner. The part about why we need additional attributes for <script> tags is probably not needed for the DEP anymore because django/django#18782 exists and is in a good state. For the DEP we should be able to assume that we already have an understanding regarding this, at least I have a lot of hope for it.

I think it would be interesting talk about importmap merging and ES module loading; I created an issue here yesterday codingjoe/django-esm#38 , but maybe this DEP would be a better place for the discussion around that.