122 lines
2.6 KiB
Python
122 lines
2.6 KiB
Python
"""
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Various edge-cases for model managers.
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"""
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from django.db import models
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from django.utils.encoding import python_2_unicode_compatible
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class OnlyFred(models.Manager):
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def get_queryset(self):
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return super(OnlyFred, self).get_queryset().filter(name='fred')
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class OnlyBarney(models.Manager):
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def get_queryset(self):
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return super(OnlyBarney, self).get_queryset().filter(name='barney')
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class Value42(models.Manager):
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def get_queryset(self):
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return super(Value42, self).get_queryset().filter(value=42)
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class AbstractBase1(models.Model):
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name = models.CharField(max_length=50)
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class Meta:
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abstract = True
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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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class AbstractBase2(models.Model):
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value = models.IntegerField()
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class Meta:
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abstract = True
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# Custom manager
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restricted = Value42()
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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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class Meta:
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abstract = True
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@python_2_unicode_compatible
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class Parent(models.Model):
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name = models.CharField(max_length=50)
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manager = OnlyFred()
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def __str__(self):
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return self.name
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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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@python_2_unicode_compatible
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class Child1(AbstractBase1):
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data = models.CharField(max_length=25)
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def __str__(self):
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return self.data
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@python_2_unicode_compatible
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class Child2(AbstractBase1, AbstractBase2):
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data = models.CharField(max_length=25)
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def __str__(self):
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return self.data
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@python_2_unicode_compatible
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class Child3(AbstractBase1, AbstractBase3):
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data = models.CharField(max_length=25)
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def __str__(self):
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return self.data
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@python_2_unicode_compatible
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class Child4(AbstractBase1):
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data = models.CharField(max_length=25)
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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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def __str__(self):
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return self.data
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@python_2_unicode_compatible
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class Child5(AbstractBase3):
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name = models.CharField(max_length=25)
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default = OnlyFred()
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objects = models.Manager()
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def __str__(self):
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return self.name
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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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# Will not inherit default manager from parent.
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class Child7(Parent):
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pass
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