Question

I’m writing a django application with a URL like ‘http://localhost/entity/id/?overlay=other_id’. Where id is the primary key of the particular entity and overlay is an optional query parameter for a second entity to be overlaid in the display. The user can only ever update an entity when viewing objects through an overlay. When POSTing to /update/id, I want to redirect back to /entity/id, but I don’t want to lose my query parameter during the redirect, as the change in view would be jarring.

For example, I’ve got the following in my url.py:

...
(r'^update/(?P<id>.+)/(?P<overlay_id>.+)/$', 'update'),
(r'^entity/(?P<id>.+)/$', 'view'),
...

Because overlay_id is required when updating, it’s part of the URL, not a query parameter. In the django view I want to redirect after a successful POST and use reverse() to avoid referencing URLs in my python code. The general idea is:

return HttpResponseRedirect(
  reverse('views.view',
    kwargs={
      'id': id,
    },
  )
)

But how do I pass my query parameter though reverse?

Thanks,
Craig

Answer 1

Can’t you just check for an overlay_id and add it to your url?

redirect_url = reverse( ... )
extra_params = '?overlay=%s' % overlay_id if overlay_id else ''
full_redirect_url = '%s%s' % (redirect_url, extra_params)
return HttpResponseRedirect( full_redirect_url )