""" Various edge-cases for model managers. """ from django.db import models class OnlyFred(models.Manager): def get_query_set(self): return super(OnlyFred, self).get_query_set().filter(name='fred') class OnlyBarney(models.Manager): def get_query_set(self): return super(OnlyBarney, self).get_query_set().filter(name='barney') class Value42(models.Manager): def get_query_set(self): return super(Value42, self).get_query_set().filter(value=42) class AbstractBase1(models.Model): name = models.CharField(max_length=50) class Meta: abstract = True # Custom managers manager1 = OnlyFred() manager2 = OnlyBarney() objects = models.Manager() class AbstractBase2(models.Model): value = models.IntegerField() class Meta: abstract = True # Custom manager restricted = Value42() # No custom manager on this class to make sure the default case doesn't break. class AbstractBase3(models.Model): comment = models.CharField(max_length=50) class Meta: abstract = True class Parent(models.Model): name = models.CharField(max_length=50) manager = OnlyFred() def __unicode__(self): return self.name # Managers from base classes are inherited and, if no manager is specified # *and* the parent has a manager specified, the first one (in the MRO) will # become the default. class Child1(AbstractBase1): data = models.CharField(max_length=25) def __unicode__(self): return self.data class Child2(AbstractBase1, AbstractBase2): data = models.CharField(max_length=25) def __unicode__(self): return self.data class Child3(AbstractBase1, AbstractBase3): data = models.CharField(max_length=25) def __unicode__(self): return self.data class Child4(AbstractBase1): data = models.CharField(max_length=25) # Should be the default manager, although the parent managers are # inherited. default = models.Manager() def __unicode__(self): return self.data class Child5(AbstractBase3): name = models.CharField(max_length=25) default = OnlyFred() objects = models.Manager() def __unicode__(self): return self.name # Will inherit managers from AbstractBase1, but not Child4. class Child6(Child4): value = models.IntegerField() # Will not inherit default manager from parent. class Child7(Parent): pass