NoReverseMatch in Django; views and urls are properly defined

Question

I am currently working on a website and I am receiving an error that is driving me up a wall. I have the following url defined in urls.py.

urlpatterns = [
    url(r'^', views.homeFeed, name='home'),
    url(r'^posts/(?P<uid>[\w+])$', views.discussPostView, name='post')
    ]

I then have the following code defining views.discussPostView.

def discussPostView(request, **kwargs):
    if request.method == 'GET':
        print(kwargs['uid'])
        post = get_object_or_404(DiscussPost, uid=kwargs['uid'])
        return render(request, 'discuss/post.html', {"post": post})
    if request.method == 'POST':
        reply = DiscussReply.objects.create(
            by=request.user,
            content=request.POST['reply'])
        reply.save()
        reply_to = DiscussPost.objects.get(pk=request.POST['post_id'])
        reply_to.replies.add(reply)
        reply_to.save()
        return HttpResponseRedirect(request.get_full_path())

However, when I try to create a post on the site or access a post with a certain uid, I receive this error;

Reverse for 'post' with arguments '()' 
and keyword arguments '{u'uid': u'CHacFvE_'}' not found. 1 pattern(s) tried: [u'discuss/posts/(?P<uid>[\\w+])$']

I literally have no idea what's wrong with my code. I am a bit rusty on python so I might be missing some obvious pointers, but any pointers in the right direction would be helpful. Thank you!

Full error stack:

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/django/core/handlers/base.py", line 149, in get_response
    response = self.process_exception_by_middleware(e, request)
  File "/usr/local/lib/python2.7/dist-packages/django/core/handlers/base.py", line 147, in get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/home/ubuntu/workspace/discuss/views.py", line 15, in homeFeed
    "feeds": [DiscussPost.getFeed(request), DiscussPost.getNewPosts()]})
  File "/usr/local/lib/python2.7/dist-packages/django/shortcuts.py", line 67, in render
    template_name, context, request=request, using=using)
  File "/usr/local/lib/python2.7/dist-packages/django/template/loader.py", line 97, in render_to_string
    return template.render(context, request)
  File "/usr/local/lib/python2.7/dist-packages/django/template/backends/django.py", line 95, in render
    return self.template.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 206, in render
    return self._render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 197, in _render
    return self.nodelist.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 988, in render
    bit = node.render_annotated(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 955, in render_annotated
    return self.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/loader_tags.py", line 173, in render
    return compiled_parent._render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 197, in _render
    return self.nodelist.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 988, in render
    bit = node.render_annotated(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 955, in render_annotated
    return self.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/loader_tags.py", line 69, in render
    result = block.nodelist.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 988, in render
    bit = node.render_annotated(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 955, in render_annotated
    return self.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/defaulttags.py", line 326, in render
    return nodelist.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 988, in render
    bit = node.render_annotated(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 955, in render_annotated
    return self.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/defaulttags.py", line 220, in render
    nodelist.append(node.render_annotated(context))
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 955, in render_annotated
    return self.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/defaulttags.py", line 220, in render
    nodelist.append(node.render_annotated(context))
  File "/usr/local/lib/python2.7/dist-packages/django/template/base.py", line 955, in render_annotated
    return self.render(context)
  File "/usr/local/lib/python2.7/dist-packages/django/template/defaulttags.py", line 513, in render
    six.reraise(*exc_info)
  File "/usr/local/lib/python2.7/dist-packages/django/template/defaulttags.py", line 499, in render
    url = reverse(view_name, args=args, kwargs=kwargs, current_app=current_app)
  File "/usr/local/lib/python2.7/dist-packages/django/core/urlresolvers.py", line 600, in reverse
    return force_text(iri_to_uri(resolver._reverse_with_prefix(view, prefix, *args, **kwargs)))
  File "/usr/local/lib/python2.7/dist-packages/django/core/urlresolvers.py", line 508, in _reverse_with_prefix
    (lookup_view_s, args, kwargs, len(patterns), patterns))
NoReverseMatch: Reverse for 'post' with arguments '()' and keyword arguments '{u'uid': u'-lTmOw__'}' not found. 1 pattern(s) tried: [u'discuss/posts/(?P<uid>[\\w]+)$']

Answer 1

What is the valid characters in the Post.uid? Your question has two examples u'CHacFvE_' from the error message and {u'uid': u'-lTmOw__'} in the stack trace.

If you want both underscores and dashes to be valid in uid, you must change the regex.

^posts/(?P<uid>[-\w]+)$

explanation: https://regex101.com/r/1E2WVY/1

Answer 2

Your pattern is wrong, try this:

'^posts/(?P<uid>\w+)$'