diff -r 5ff1fc726848 -r c6bca38c1cbf parts/django/tests/modeltests/custom_managers/models.py --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/parts/django/tests/modeltests/custom_managers/models.py Sat Jan 08 11:20:57 2011 +0530 @@ -0,0 +1,59 @@ +""" +23. Giving models a custom manager + +You can use a custom ``Manager`` in a particular model by extending the base +``Manager`` class and instantiating your custom ``Manager`` in your model. + +There are two reasons you might want to customize a ``Manager``: to add extra +``Manager`` methods, and/or to modify the initial ``QuerySet`` the ``Manager`` +returns. +""" + +from django.db import models + +# 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) + +# An example of a custom manager that sets get_query_set(). + +class PublishedBookManager(models.Manager): + def get_query_set(self): + return super(PublishedBookManager, self).get_query_set().filter(is_published=True) + +class Book(models.Model): + title = models.CharField(max_length=50) + author = models.CharField(max_length=30) + is_published = models.BooleanField() + published_objects = PublishedBookManager() + authors = models.ManyToManyField(Person, related_name='books') + + def __unicode__(self): + return self.title + +# An example of providing multiple custom managers. + +class FastCarManager(models.Manager): + def get_query_set(self): + return super(FastCarManager, self).get_query_set().filter(top_speed__gt=150) + +class Car(models.Model): + name = models.CharField(max_length=10) + mileage = models.IntegerField() + top_speed = models.IntegerField(help_text="In miles per hour.") + cars = models.Manager() + fast_cars = FastCarManager() + + def __unicode__(self): + return self.name