[patch] Allow callables in extra_lookup_kwargs of generic views

[Tom Tobin <korpios@…>]

As with #195, it would be nice to allow callables in the extra_lookup_kwargs of generic views for similar reasons (e.g., a blog could pass in something like {'time_published__lte': datetime.now}).

[hugo]

Duplicate to #667

[Tom Tobin <korpios@…>]

This isn't a duplicate of #667; it's along the lines of #195. I was talking about plain callables (with no args, like datetime.now), not callbacks.

[Tom Tobin <korpios@…>]

Patch against r1217 to implement callables for extra_lookup_kwargs

[Tom Tobin <korpios@…>]

Added a patch to implement the behavior in question.

[hugo]

I still think that #667 is a super-set of this - it asks for callables that get parameters (request and url parts). Your case could be done by using "lambda request, parts: datetime.datetime.now()" as the callable/. It would additionally allow to do processing based on request parameters or url parts - which your patch wouldn't allow. The more general case would be really helpful - think about ?q=searchword paramters that are turned into fieldcontains=searchword lookup kwargs.

[Tom Tobin <korpios@…>]

Patch against r1217 to implement callables for extra_lookup_kwargs (fixed)

[Tom Tobin <korpios@…>]

Added a patch to implement originally discussed behavior for all generic views, as I realized my original patch only handled list_detail's object_list.

If you think the requested behavior in #667 is more useful, and can be applied equally well to this case, I'll take a shot at implementing that instead.

[hugo]

I think both could be combined - #667 would be best implemented by asking wether extra_lookup_kwargs is a callable, your patch looks for items to be callables. If extra_lookup_kwargs is a callable, this could easily be used for your problem:

info_dict = {
  # ...
  'extra_lookup_kwargs': lambda request, **parms: {'time_published__lte': datetime.datetime.now()},
  # ...

That would do the same as your patch, only it would allow do even more. The difference in your patch would be to not check each item for a callable, but instead check the full extra_lookup_kwargs element for a callable and if it is one, call it with passing the request and the keyword parameters from the generic view to it.

My case would then be something like this:

def current_posts(request, **parms):
   kwargs = {
      'time_published__lte': datetime.datetime.now(),
   }
   if request.GET.has_key('q'):
      kwargs['title__contains'] = rquest.GET['q']
   return kwargs

info_dict = {
   # ...
   'extra_lookup_kwargs': current_posts,
   # ...
}

This would do the same as yours, but additionally would automatically filter posts by title if the users passes in a ?q=search+words parameter to the generic view URL.

[ian@…]

I did something similar to this (based on hugo's work)
here
​http://svn.zilbo.com/svn/django/common/filter/views/filter.py

it checks to see if the argument matches a field, and then adds the filter if it does.

[Tom Tobin <korpios@…>]

See #667; patch with the callback behavior for extra_lookup_kwargs (but not extra_context yet).

[Adrian Holovaty]

I'm closing this, as generic views no longer take extra_lookup_kwargs.