Figure out why redirects aren't working

[alanmoo]

Redirects added at https://foundation.mozilla.org/admin/redirects/redirect/ aren't working (they 404). Let's figure out why.

[alanmoo]

It appears that locally it's doing a 301. That's...not ideal, as the redirect I want to use for now will eventually be disabled to hit pages served by Mezzanine

From https://docs.djangoproject.com/en/2.0/ref/contrib/redirects/
You can subclass RedirectFallbackMiddleware and set response_redirect_class to django.http.HttpResponseRedirect to use a 302 Moved Temporarily redirect instead.

[cadecairos]

Here's what I found out:

• Only breaks when DEBUG=False
• The view handler handler404 in urls.py is a RedirectView, so it's returning a 302 response to /errors/404 if the router can't match the requested path to a view.
• When DEBUG=True handler404 doesn't execute, it seems.
• Handler404 turns what would be 404s into 302s, so when the RedirectMiddlware is executed for the request, it doesn't do anything, because it only looks for 404s

In order to fix this, our handler404 can't set the response code to 302 before the redirect middleware executes. I see two ways forward:

1. Make the 404 page a view in Django
2. Remove the handler404 setting, and sub-class the RedirectMiddleware to do what we want (lookup redirects in the DB, or redirect to /error/404

[cadecairos]

@alanmoo This is still assigned to me - we need to make a decision as to which way to fix this. I'm okay with either of the options I laid out, however #2 diverges our code from Django/Mezzanine core even more, which might burn us in the future.

[alanmoo]

Then yeah, let's stick with option 1. What's the actual work required for that? It might be something we can leave up for a contributor to pick up if they're interested until someone on the team has a chance to get to it.

[alanmoo]

Will this be resolved once Wagtail is handling our 404's?

[cadecairos]

It should be resolved once we stop relying on a statically built frontend that's served via whitenoise.

[kristinashu]

Will redirects work now?

[cadecairos]

Not yet, we still need fix the problems outlined in this comment

[alanmoo]

We have stopped serving those pages statically, and I believe I added a djano-based 404 page last week.

[cadecairos]

if it's ready to go, we should update this line so that it's not a redirect to a static page.