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	Also added documentation describing how manager inheritance works (and when manager aren't inherited). Based on some patches from sebastian_noack and emulbreh. git-svn-id: http://code.djangoproject.com/svn/django/trunk@8851 bcc190cf-cafb-0310-a4f2-bffc1f526a37
		
			
				
	
	
		
			154 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			154 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| """
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| Various edge-cases for model managers.
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| """
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| 
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| from django.db import models
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| 
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| class OnlyFred(models.Manager):
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|     def get_query_set(self):
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|         return super(OnlyFred, self).get_query_set().filter(name='fred')
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| 
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| class OnlyBarney(models.Manager):
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|     def get_query_set(self):
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|         return super(OnlyBarney, self).get_query_set().filter(name='barney')
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| 
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| class Value42(models.Manager):
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|     def get_query_set(self):
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|         return super(Value42, self).get_query_set().filter(value=42)
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| 
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| class AbstractBase1(models.Model):
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|     name = models.CharField(max_length=50)
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| 
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|     class Meta:
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|         abstract = True
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| 
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|     # Custom managers
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|     manager1 = OnlyFred()
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|     manager2 = OnlyBarney()
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|     objects = models.Manager()
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| 
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| class AbstractBase2(models.Model):
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|     value = models.IntegerField()
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| 
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|     class Meta:
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|         abstract = True
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| 
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|     # Custom manager
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|     restricted = Value42()
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| 
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| # No custom manager on this class to make sure the default case doesn't break.
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| class AbstractBase3(models.Model):
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|     comment = models.CharField(max_length=50)
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| 
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|     class Meta:
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|         abstract = True
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| 
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| class Parent(models.Model):
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|     name = models.CharField(max_length=50)
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| 
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|     manager = OnlyFred()
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| 
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|     def __unicode__(self):
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|         return self.name
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| 
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| # Managers from base classes are inherited and, if no manager is specified
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| # *and* the parent has a manager specified, the first one (in the MRO) will
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| # become the default.
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| class Child1(AbstractBase1):
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|     data = models.CharField(max_length=25)
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| 
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|     def __unicode__(self):
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|         return self.data
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| 
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| class Child2(AbstractBase1, AbstractBase2):
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|     data = models.CharField(max_length=25)
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| 
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|     def __unicode__(self):
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|         return self.data
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| 
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| class Child3(AbstractBase1, AbstractBase3):
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|     data = models.CharField(max_length=25)
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| 
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|     def __unicode__(self):
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|         return self.data
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| 
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| class Child4(AbstractBase1):
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|     data = models.CharField(max_length=25)
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| 
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|     # Should be the default manager, although the parent managers are
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|     # inherited.
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|     default = models.Manager()
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| 
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|     def __unicode__(self):
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|         return self.data
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| 
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| class Child5(AbstractBase3):
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|     name = models.CharField(max_length=25)
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| 
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|     default = OnlyFred()
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|     objects = models.Manager()
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| 
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|     def __unicode__(self):
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|         return self.name
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| 
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| # Will inherit managers from AbstractBase1, but not Child4.
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| class Child6(Child4):
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|     value = models.IntegerField()
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| 
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| # Will not inherit default manager from parent.
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| class Child7(Parent):
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|     pass
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| 
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| __test__ = {"API_TESTS": """
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| >>> a1 = Child1.objects.create(name='fred', data='a1')
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| >>> a2 = Child1.objects.create(name='barney', data='a2')
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| >>> b1 = Child2.objects.create(name='fred', data='b1', value=1)
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| >>> b2 = Child2.objects.create(name='barney', data='b2', value=42)
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| >>> c1 = Child3.objects.create(name='fred', data='c1', comment='yes')
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| >>> c2 = Child3.objects.create(name='barney', data='c2', comment='no')
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| >>> d1 = Child4.objects.create(name='fred', data='d1')
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| >>> d2 = Child4.objects.create(name='barney', data='d2')
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| >>> e1 = Child5.objects.create(name='fred', comment='yes')
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| >>> e2 = Child5.objects.create(name='barney', comment='no')
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| >>> f1 = Child6.objects.create(name='fred', data='f1', value=42)
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| >>> f2 = Child6.objects.create(name='barney', data='f2', value=42)
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| >>> g1 = Child7.objects.create(name='fred')
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| >>> g2 = Child7.objects.create(name='barney')
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| 
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| >>> Child1.manager1.all()
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| [<Child1: a1>]
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| >>> Child1.manager2.all()
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| [<Child1: a2>]
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| >>> Child1._default_manager.all()
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| [<Child1: a1>]
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| 
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| >>> Child2._default_manager.all()
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| [<Child2: b1>]
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| >>> Child2.restricted.all()
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| [<Child2: b2>]
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| 
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| >>> Child3._default_manager.all()
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| [<Child3: c1>]
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| >>> Child3.manager1.all()
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| [<Child3: c1>]
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| >>> Child3.manager2.all()
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| [<Child3: c2>]
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| 
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| # Since Child6 inherits from Child4, the corresponding rows from f1 and f2 also
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| # appear here. This is the expected result.
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| >>> Child4._default_manager.order_by('data')
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| [<Child4: d1>, <Child4: d2>, <Child4: f1>, <Child4: f2>]
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| >>> Child4.manager1.all()
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| [<Child4: d1>, <Child4: f1>]
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| 
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| >>> Child5._default_manager.all()
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| [<Child5: fred>]
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| 
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| >>> Child6._default_manager.all()
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| [<Child6: f1>]
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| 
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| >>> Child7._default_manager.order_by('name')
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| [<Child7: barney>, <Child7: fred>]
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| 
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| """}
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