Django models, custom functions

Question

I am creating simple application with django. Also, I realized that I am doing some kind of operations very often. For example I often need to get all Article objects which have isPublick = True. So I am thinking is that possible to define get_published function in model?

if models looks like this (simplified)

class Article(models.Model):     title = models.CharField(...)     isPublished = models.BooleandField()      def get_active(self):        return Article.objects.filter(isPublicshed = 1) 

But it doesn't work this way

Can you suggest a way of implementing the function?

Answer 1

What you probably want is a custom manager

From the django docs:

        # An example of a custom manager called "objects".  class PersonManager(models.Manager):     def get_fun_people(self):         return self.filter(fun=True)  class Person(models.Model):     first_name = models.CharField(max_length=30)     last_name = models.CharField(max_length=30)     fun = models.BooleanField()     objects = PersonManager()      def __unicode__(self):         return u"%s %s" % (self.first_name, self.last_name) 

which then allows you to do something like:

>>> p1 = Person(first_name='Bugs', last_name='Bunny', fun=True) >>> p1.save() >>> p2 = Person(first_name='Droopy', last_name='Dog', fun=False) >>> p2.save() >>> Person.objects.get_fun_people() [<Person: Bugs Bunny>]