django custom manager with filter parameter

django, django-managers, django-models, django-views

Solution

I'd simplify it:

class CurrentManager(models.Manager):
    def current(self, my_date):
        return super(CurrentManager, self).get_query_set().filter(valid_from__lte=my_date)

and then use it like this:

a = A.objects.get(id=a_id)
my_date = request.user.get_profile().my_date
b_objects = a.b_set.objects.current(my_date)

and then just pass a to the template as the filtered objects accessing them using this:

{% for b in b_objects %}

Hope this helps!

Edit (by requestor):

I had to adjust it as follows to get it working:

a = A.objects.get(id=a_id)
my_date = request.user.get_profile().my_date
b_objects = a.b_set.current(my_date)

This threw an error: "'RelatedManager' object has no attribute 'objects'"

a.b_set.objects.current(my_date)

Problem

I would like to add a custom manager which can be called from a template, but does not affect the entire model (e.g. admin views) and which listens to a parameter set in the request (user_profile). The following is what I have so far: models.py: ``` class CurrentQuerySet(models.query.QuerySet): def current(self): return self.filter(id=1) ## this simplified filter test works.. class CurrentManager(models.Manager): use_for_related_fields = True def get_query_set(self): return CurrentQuerySet(self.model) def current(self, *args, **kwargs): return self.get_query_set().current(*args, **kwargs) ``` For model B is defined: ``` objects = CurrentManager() ``` The template calls: ``` {% for b in a.b_set.current %} ``` But as soon as I try to pass a parameter to that filter (in this case a date stored on the user-profile) the method does not return any results. e.g.: models.py ``` class CurrentQuerySet(models.query.QuerySet): def current(self,my_date): return self.filter(valid_from__lte=my_date) ``` showA.html ``` {% for b in a.b_set.current(request.user.get_profile.my_date) %} ``` Instead of passing the parameter from the template, I have also tried to set this in the view.py ``` @login_required def showA(request,a_id): my_date = request.user.get_profile().my_date a = A.objects.get(id=a_id) t = loader.get_template('myapp/showA.html') c = RequestContext(request,{'a':a,'my_date':my_date,}) return HttpResponse(t.render(c)) ``` Which part am I missing (or misunderstanding) here? Thanks R Edit Here the models. As mentioned, in this example it's a simple 1:n relationship, but can also be m:n in other cases. ``` class A(models.Model): #objects = CurrentManager() a = models.CharField(max_length=200) description = models.TextField(null=True,blank=True) valid_from = models.DateField('valid from') valid_to = models.DateField('valid to',null=True,blank=True) def __unicode__(self): return self.a class B(models.Model): #objects = models.Manager() objects = CurrentManager() a = models.ForeignKey(A) b = models.CharField(max_length=200) screenshot = models.ManyToManyField("Screenshot",through="ScreenshotToB") description = models.TextField(null=True,blank=True) valid_from = models.DateField('valid from') valid_to = models.DateField('valid to',null=True,blank=True) def __unicode__(self): return self.b ``` Edit-2 The accepted answer works for at least one relationship. In case of a more nested data model, this method seems not to deliver the expected results: models.py ``` class C(models.Model): objects = CurrentManager() b = models.ForeignKey(A) c = models.CharField(max_length=200) description = models.TextField(null=True,blank=True) valid_from = models.DateField('valid from') valid_to = models.DateField('valid to',null=True,blank=True) def __unicode__(self): return self.c ``` views.py ``` @login_required def showA(request,a_id): a = A.objects.get(id=a_id) my_date = request.user.get_profile().my_date b_objects = a.b_set.current(my_date) c_objects = b_objects.c_set.current(my_date) t = loader.get_template('controltool2/showA.html') c = RequestContext(request,{'a':a,'b_objects':b_objects,'c_objects':c_objects,}) return HttpResponse(t.render(c)) ``` This returns the error: `'QuerySet' object has no attribute 'c_set'`.

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