contrib.comments should allow users to specify their own template on error

[Teebes]

Currently in contrib.comments, if there is an error on the form the user is taken to a page that is generated by the preview template. This means that you can't have the user stay on the exact same page they were on if they submitted it with a mistake.

This patch introduces a new parameter to post_comment in contrib.comments.views.comments, that is None by default but that can contain an overwrite template location and extra context variable.

To get this to work, a user would just need to overwrite the comments/post url in urls.py and make it point to a custom wrapper around post_comment. For example:

urls.py:

    (r'^comments/post/$', 'thebes.quanda_comments.views.custom_post_comment'),

quanda_comments/views.py:

from django.contrib.comments.views.comments import post_comment
from django.http import HttpResponseRedirect

from thebes.quanda.models import Answer

def custom_post_comment(request):
    
    answers = Answer.objects.all()
    
    error_page = {
        'template': 'quanda/index.html',
        'data': { 'answers': answers },
    }
    response = post_comment(request, error_page=error_page)
    return response

The impact is minimal, with only one file changed and no reverse compatibility issues. I've inclued both code path and documentation patch.

[Teebes]

Patch to contrib.comments (code & documentation) to allow error template selection

[Teebes]

I forgot to mention that this originated in the following stackoverflow thread:
​http://stackoverflow.com/questions/1174140/django-comments-how-to-prevent-form-errors-from-redirecting-the-user-to-the-prev

[Russell Keith-Magee]

Nothing wrong with the idea, but it should be implemented in a way that maintains parity with other configurable template views (like the generic views). This means passing in a template_name and extra_context arguments, rather than a dictionary.

[Julien Phalip]

Patch needs improvement as per Russell's comment. Also needs tests and (better) doc to reflect the requested improvement.

[Aymeric Augustin]

Change UI/UX from NULL to False.

[Aymeric Augustin]

Change Easy pickings from NULL to False.

[Jacob]

django.contrib.comments has been deprecated and is no longer supported, so I'm closing this ticket. We're encouraging users to transition to a custom solution, or to a hosted solution like Disqus.

The code itself has moved to ​https://github.com/django/django-contrib-comments; if you want to keep using it, you could move this bug over there.