mimetype used with HttpResponse should be deprecated

[Paul McMillan]

Passing the mimetype argument when instantiating HttpResponse should raise a DeprecationWarning.

The mimetype argument has been deprecated via comment in the code for 4 years: https://code.djangoproject.com/changeset/5844/django/trunk/django/http/__init__.py

It's about time we actually raised a DeprecationWarning and remove the thing ASAP. If we swap the position of the mimetype and content_type arguments, code the relies on argument position will continue to function without raising the warning. The only code that will need to be changed is code that explicitly uses the mimetype kwarg (including a bunch of django tests).

This situation is long-lived enough to bypass the PendingDeprecationWarning.

[Jannis Leidel]

I don't think it hurts to keep the backwards compatibility code for another release, so this should definitely be a PendingDeprecationWarning

[Paul McMillan]

Alright. I suppose it doesn't hurt anything. And as to the matter of re-ordering the kwargs? That'll fix a great deal of existing code directly.

[Yaşar Arabacı]

I am new to contributing, and I shoud ask if I should fix contrib packages too. I mean replacing mimetype with content_type where needed?

[Paul McMillan]

Yes, you'll need to fix it everywhere it occurs in the Django codebase, including the tests. You'll also probably need to write some new tests. If you swap the order of mimetype and content_type in the definition, the functions that are using mimetype as a positional argument will transition more easily.

[Yaşar Arabacı]

Ok. A patch would be available in couple of days I guess. I am excited as this will be my first actual contrib to django :)

[Ramiro Morales]

Replying to yasar11732:

I am new to contributing, and I shoud ask if I should fix contrib packages too. I mean replacing mimetype with content_type where needed?

If you are talking about django.contrib.* then the answer is yes. Thanks for looking at this.

[Yaşar Arabacı]

Fixed all necessary things, but didn't write tests.

[Yaşar Arabacı]

I made a patch file where I made warning and changed mimetype kwarg, to content_type kwarg. However, I didn't write tests for it, as I am not sure what I am test for here, something like this maybe?

import warnings
from django.http import HttpResponse

with warnings.catch_warnings(record=True) as w:
    warnings.simplefilter("always")
    HttpResponse(mimetype="text/html")

    assert len(w) == 1
    assert issubclass(w[-1].category, DeprecationWarning)
    assert "deprecated" in str(w[-1].message)

[Yaşar Arabacı]

Sorry about marking as RFC. I didn't know I didn't supposed to do that.

[Adrian Holovaty]

In [17223]:

Converted some of the built-in views to use content_type instead of mimetype HttpResponse argument. Refs #16519

[Claude Paroz <claude@…>]

In [deed192dda621f1cdc8eb7240f1e5914045402dd]:

Removed usage of mimetype kwarg of HttpResponse

Refs #16519.

[Claude Paroz <claude@…>]

In [da200c5e35cdbb617572977bcbf97fae33920b2e]:

Fixed #16519 -- Deprecated mimetype kwarg of HttpResponse init

This keyword was already deprecated in the code (supported for
backwards compatibility only), but never formally deprecated.
Thanks Paul McMillan for the report and yasar11732 for the initial
patch.