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Diffstat (limited to 'tests/modeltests/custom_managers/models.py')
| -rw-r--r-- | tests/modeltests/custom_managers/models.py | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/tests/modeltests/custom_managers/models.py b/tests/modeltests/custom_managers/models.py new file mode 100644 index 0000000000..a6ae80029a --- /dev/null +++ b/tests/modeltests/custom_managers/models.py @@ -0,0 +1,100 @@ +""" +23. Giving models a custom manager +""" + +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(maxlength=30) + last_name = models.CharField(maxlength=30) + fun = models.BooleanField() + objects = PersonManager() + + def __repr__(self): + return "%s %s" % (self.first_name, self.last_name) + +# An example of a custom manager that sets a core_filter on its lookups. + +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(maxlength=50) + author = models.CharField(maxlength=30) + is_published = models.BooleanField() + published_objects = PublishedBookManager() + authors = models.ManyToManyField(Person, related_name='books') + + def __repr__(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(maxlength=10) + mileage = models.IntegerField() + top_speed = models.IntegerField(help_text="In miles per hour.") + cars = models.Manager() + fast_cars = FastCarManager() + + def __repr__(self): + return self.name + +API_TESTS = """ +>>> 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() +[Bugs Bunny] + +# The RelatedManager used on the 'books' descriptor extends the default manager +>>> from modeltests.custom_managers.models import PublishedBookManager +>>> isinstance(p2.books, PublishedBookManager) +True + +>>> b1 = Book(title='How to program', author='Rodney Dangerfield', is_published=True) +>>> b1.save() +>>> b2 = Book(title='How to be smart', author='Albert Einstein', is_published=False) +>>> b2.save() + +# The default manager, "objects", doesn't exist, +# because a custom one was provided. +>>> Book.objects +Traceback (most recent call last): + ... +AttributeError: type object 'Book' has no attribute 'objects' + +# The RelatedManager used on the 'authors' descriptor extends the default manager +>>> from modeltests.custom_managers.models import PersonManager +>>> isinstance(b2.authors, PersonManager) +True + +>>> Book.published_objects.all() +[How to program] + +>>> c1 = Car(name='Corvette', mileage=21, top_speed=180) +>>> c1.save() +>>> c2 = Car(name='Neon', mileage=31, top_speed=100) +>>> c2.save() +>>> Car.cars.order_by('name') +[Corvette, Neon] +>>> Car.fast_cars.all() +[Corvette] + +# Each model class gets a "_default_manager" attribute, which is a reference +# to the first manager defined in the class. In this case, it's "cars". +>>> Car._default_manager.order_by('name') +[Corvette, Neon] +""" |
