How do I construct a Django reverse/url using query args?
- by Andrew Dalke
I have URLs like http://example.com/depict?smiles=CO&width=200&height=200 (and with several other optional arguments)
My urls.py contains:
urlpatterns = patterns('',
(r'^$', 'cansmi.index'),
(r'^cansmi$', 'cansmi.cansmi'),
url(r'^depict$', cyclops.django.depict, name="cyclops-depict"),
I can go to that URL and get the 200x200 PNG that was constructed, so I know that part works.
In my template from the "cansmi.cansmi" response I want to construct a URL for the named template "cyclops-depict" given some query parameters. I thought I could do
{% url cyclops-depict smiles=input_smiles width=200 height=200 %}
where "input_smiles" is an input to the template via a form submission. In this case it's the string "CO" and I thought it would create a URL like the one at top.
This template fails with a TemplateSyntaxError:
Caught an exception while rendering: Reverse for 'cyclops-depict' with arguments '()' and keyword arguments '{'smiles': u'CO', 'height': 200, 'width': 200}' not found.
This is a rather common error message both here on StackOverflow and elsewhere. In every case I found, people were using them with parameters in the URL path regexp, which is not the case I have where the parameters go into the query.
That means I'm doing it wrong. How do I do it right? That is, I want to construct the full URL, including path and query parameters, using something in the template.
For reference,
% python manage.py shell
Python 2.6.1 (r261:67515, Feb 11 2010, 00:51:29)
[GCC 4.2.1 (Apple Inc. build 5646)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> from django.core.urlresolvers import reverse
>>> reverse("cyclops-depict", kwargs=dict())
'/depict'
>>> reverse("cyclops-depict", kwargs=dict(smiles="CO"))
Traceback (most recent call last):
File "<console>", line 1, in <module>
File "/Library/Python/2.6/site-packages/django/core/urlresolvers.py", line 356, in reverse
*args, **kwargs)))
File "/Library/Python/2.6/site-packages/django/core/urlresolvers.py", line 302, in reverse
"arguments '%s' not found." % (lookup_view_s, args, kwargs))
NoReverseMatch: Reverse for 'cyclops-depict' with arguments '()' and keyword arguments '{'smiles': 'CO'}' not found.
