Django, query filtering from model method

Question

Hello, I have these models:

def Foo(Models.model):
    size = models.IntegerField()
    ....some other vars...

    def is_active(self):
         if ...checks something here...
              return True
         else:
              return False

def Bar(Models.model):
     foo = models.ForeignKey("Foo")
     ....some other vars...

Now I want to query Bars that are having active Foo's as such:

Bar.objects.filter(foo.is_active())

I am getting error such as

   SyntaxError at /
  ('non-keyword arg after keyword arg'

How can I achieve this?

Answer 1

You cannot query against model methods or properties. Either use the criteria within it in the query, or filter in Python using a list comprehension or genex.

Answer 2

You can't filter on methods, however if the is_active method on Foo checks an attribute on Foo, you can use the double-underscore syntax like Bar.objects.filter(foo__is_active_attribute=True)