How to use namespace urls with django in a reusuable app - django

Question

I have a django app, a forum app, that has templates with it. In those templates, there are urls that point to parts of the app. For instance the thread_list template has links to each thread like so:
{% for thread in threads %}
{{thread.title}}
{% endfor %}
The thing is, I don't really like calling my urls "forum_thread". I prefer just "thread" and using the namespace feature of django. "forum_thread" may be used somewhere else in the project (namespace collision).So it will look like this:
{% for thread in threads %}
{{thread.title}}
{% endfor %}
but this doesn't feel like the correct way to do this. The docs are kind of unclear here.
I want this app to be reusable and easy to configure. But I also want to use the best standards. I don't want to have the to make the user specify their own namespace name, and then have them edit every single url in each template.
How should I do urls in this app?

Answer 1

From what I can gather you should be able use {% url forum:thread thread %} as you've described. Namespaces always seem to be defined with two variables, namespace and app_name.
If you then do the following in urls.py:
url(r'^/forum/', include('forum.urls', namespace='forum', app_name='forum')),
url(r'^/foo/', include('forum.urls', namespace='foo', app_name='forum')),
url(r'^/bar/', include('forum.urls', namespace='bar', app_name='forum')),
In my understanding, this defines 3 instances of the app 'forum', 'foo', 'bar', and the default (which has namespace==app_name).
When you reverse forum:thread, it uses the current context to determine which one to use- if you are in namespace 'foo' it will use that, otherwise it will fall back on the default.
If anyone is able to clarify how Django decides what the 'current' namespace/app is that would be very helpful. I currently categorise it as 'black magic'.
Some clarification on the actual difference between namespace and app_name would also be helpful- it's possible that I have this totally reversed. The current docs are highly ambiguous.
Note: I have this working for initial requests, but I'm currently unable to make this work for AJAX requests- those always use the default instance for some reason.

Answer 2

This might be a simple syntax error. I was following the Django Tutorial, and I changed mysite/urls.py improperly. The original syntax:
url(r'^polls/', include('polls.urls')),
The desired change:
url(r'^polls/', include('polls.urls', namespace="polls")),
What I did:
url(r'^polls/', include('polls.urls'), namespace="polls"),
Correcting the syntax resolved the issue.

Answer 3

based on my understanding of this question:
in Django 2.1.7
You can app name in app's urls.py file
# app's urls.py
from django.urls import path
from . import views
app_name = 'forum'
urlpatterns = [
path('thread/', views.mark_done, name='thread')
]
in main urls.py
# urls.py
....
urlpatterns = [
path('forum/', include('forum.urls')),
]
then you can employ {% url 'forum:thread' %} in your template
If you wanna use it in a for loop
I think we should
create a view return all threads as context
then add a path to that view
...
path('thread/<int:pk>', views.mark_done, name='thread')
the url in template will like:
{% for thread in threads %}
{{thread.title}}
{% endfor %}