Question

Is this possible to change variable after it’s been catched by url dispatcher and pass it to view changed?

For example:
I’ve got following urlpattern

urlpatterns = patterns('',
    (r'^articles/(?P<article_id>\d+)/$', 'article.views.article_view'),
)

I want to change article_id before passing it to article.views.article_view

I need this, as an override. I’ve got article app which can’t be changed, but I must use it. :-/

Answer 1

Use a wrapper view. Map the URL to your own view which then calls article.views.article_view. You can then change whatever you want within you wrapper view.

Example:

urlpatterns = patterns('',
    (r'^articles/(?P<article_id>\d+)/$', 'article_wrapper.wrap_article_view'),
)

In article_wrapper.py:

import article
def wrap_article_view(request, article_id):
    article_id = modify_it(article_id)
    return article.views.article_view(request, article_id)

Update:

If you need to do the same article_id translation for several views, you can probably make the wrapper more generic. Example:

urlpatterns = patterns('',
    url(r'^articles/(?P<article_id>\d+)/$', 
        view='article_wrapper.generic_article_wrapper',
        kwargs={'view_name':'article_view'}
    ),
)

and in article_wrapper.py:

import article
def generic_article_wrapper(request, article_id, view_name=None):
    article_id = modify_it(article_id)
    try:
        view = get_attr(article.views, view_name)
    except AttributeError:
        # handle invalid view name
    return view(request, article_id)