import datetime import pickle from io import StringIO from operator import attrgetter from unittest.mock import Mock from django.contrib.auth.models import User from django.contrib.contenttypes.models import ContentType from django.core import management from django.db import DEFAULT_DB_ALIAS, router, transaction from django.db.models import signals from django.db.utils import ConnectionRouter from django.test import SimpleTestCase, TestCase, override_settings from .models import Book, Person, Pet, Review, UserProfile from .routers import AuthRouter, TestRouter, WriteRouter class QueryTestCase(TestCase): databases = {"default", "other"} def test_db_selection(self): "Querysets will use the default database by default" self.assertEqual(Book.objects.db, DEFAULT_DB_ALIAS) self.assertEqual(Book.objects.all().db, DEFAULT_DB_ALIAS) self.assertEqual(Book.objects.using("other").db, "other") self.assertEqual(Book.objects.db_manager("other").db, "other") self.assertEqual(Book.objects.db_manager("other").all().db, "other") def test_default_creation(self): "Objects created on the default database don't leak onto other databases" # Create a book on the default database using create() Book.objects.create(title="Pro Django", published=datetime.date(2008, 12, 16)) # Create a book on the default database using a save dive = Book() dive.title = "Dive into Python" dive.published = datetime.date(2009, 5, 4) dive.save() # Book exists on the default database, but not on other database try: Book.objects.get(title="Pro Django") Book.objects.using("default").get(title="Pro Django") except Book.DoesNotExist: self.fail('"Pro Django" should exist on default database') with self.assertRaises(Book.DoesNotExist): Book.objects.using("other").get(title="Pro Django") try: Book.objects.get(title="Dive into Python") Book.objects.using("default").get(title="Dive into Python") except Book.DoesNotExist: self.fail('"Dive into Python" should exist on default database') with self.assertRaises(Book.DoesNotExist): Book.objects.using("other").get(title="Dive into Python") def test_other_creation(self): "Objects created on another database don't leak onto the default database" # Create a book on the second database Book.objects.using("other").create( title="Pro Django", published=datetime.date(2008, 12, 16) ) # Create a book on the default database using a save dive = Book() dive.title = "Dive into Python" dive.published = datetime.date(2009, 5, 4) dive.save(using="other") # Book exists on the default database, but not on other database try: Book.objects.using("other").get(title="Pro Django") except Book.DoesNotExist: self.fail('"Pro Django" should exist on other database') with self.assertRaises(Book.DoesNotExist): Book.objects.get(title="Pro Django") with self.assertRaises(Book.DoesNotExist): Book.objects.using("default").get(title="Pro Django") try: Book.objects.using("other").get(title="Dive into Python") except Book.DoesNotExist: self.fail('"Dive into Python" should exist on other database') with self.assertRaises(Book.DoesNotExist): Book.objects.get(title="Dive into Python") with self.assertRaises(Book.DoesNotExist): Book.objects.using("default").get(title="Dive into Python") def test_refresh(self): dive = Book(title="Dive into Python", published=datetime.date(2009, 5, 4)) dive.save(using="other") dive2 = Book.objects.using("other").get() dive2.title = "Dive into Python (on default)" dive2.save(using="default") dive.refresh_from_db() self.assertEqual(dive.title, "Dive into Python") dive.refresh_from_db(using="default") self.assertEqual(dive.title, "Dive into Python (on default)") self.assertEqual(dive._state.db, "default") def test_refresh_router_instance_hint(self): router = Mock() router.db_for_read.return_value = None book = Book.objects.create( title="Dive Into Python", published=datetime.date(1957, 10, 12) ) with self.settings(DATABASE_ROUTERS=[router]): book.refresh_from_db() router.db_for_read.assert_called_once_with(Book, instance=book) def test_basic_queries(self): "Queries are constrained to a single database" dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) dive = Book.objects.using("other").get(published=datetime.date(2009, 5, 4)) self.assertEqual(dive.title, "Dive into Python") with self.assertRaises(Book.DoesNotExist): Book.objects.using("default").get(published=datetime.date(2009, 5, 4)) dive = Book.objects.using("other").get(title__icontains="dive") self.assertEqual(dive.title, "Dive into Python") with self.assertRaises(Book.DoesNotExist): Book.objects.using("default").get(title__icontains="dive") dive = Book.objects.using("other").get(title__iexact="dive INTO python") self.assertEqual(dive.title, "Dive into Python") with self.assertRaises(Book.DoesNotExist): Book.objects.using("default").get(title__iexact="dive INTO python") dive = Book.objects.using("other").get(published__year=2009) self.assertEqual(dive.title, "Dive into Python") self.assertEqual(dive.published, datetime.date(2009, 5, 4)) with self.assertRaises(Book.DoesNotExist): Book.objects.using("default").get(published__year=2009) years = Book.objects.using("other").dates("published", "year") self.assertEqual([o.year for o in years], [2009]) years = Book.objects.using("default").dates("published", "year") self.assertEqual([o.year for o in years], []) months = Book.objects.using("other").dates("published", "month") self.assertEqual([o.month for o in months], [5]) months = Book.objects.using("default").dates("published", "month") self.assertEqual([o.month for o in months], []) def test_m2m_separation(self): "M2M fields are constrained to a single database" # Create a book and author on the default database pro = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) marty = Person.objects.create(name="Marty Alchin") # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) mark = Person.objects.using("other").create(name="Mark Pilgrim") # Save the author relations pro.authors.set([marty]) dive.authors.set([mark]) # Inspect the m2m tables directly. # There should be 1 entry in each database self.assertEqual(Book.authors.through.objects.using("default").count(), 1) self.assertEqual(Book.authors.through.objects.using("other").count(), 1) # Queries work across m2m joins self.assertEqual( list( Book.objects.using("default") .filter(authors__name="Marty Alchin") .values_list("title", flat=True) ), ["Pro Django"], ) self.assertEqual( list( Book.objects.using("other") .filter(authors__name="Marty Alchin") .values_list("title", flat=True) ), [], ) self.assertEqual( list( Book.objects.using("default") .filter(authors__name="Mark Pilgrim") .values_list("title", flat=True) ), [], ) self.assertEqual( list( Book.objects.using("other") .filter(authors__name="Mark Pilgrim") .values_list("title", flat=True) ), ["Dive into Python"], ) # Reget the objects to clear caches dive = Book.objects.using("other").get(title="Dive into Python") mark = Person.objects.using("other").get(name="Mark Pilgrim") # Retrieve related object by descriptor. Related objects should be # database-bound. self.assertEqual( list(dive.authors.values_list("name", flat=True)), ["Mark Pilgrim"] ) self.assertEqual( list(mark.book_set.values_list("title", flat=True)), ["Dive into Python"], ) def test_m2m_forward_operations(self): "M2M forward manipulations are all constrained to a single DB" # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) mark = Person.objects.using("other").create(name="Mark Pilgrim") # Save the author relations dive.authors.set([mark]) # Add a second author john = Person.objects.using("other").create(name="John Smith") self.assertEqual( list( Book.objects.using("other") .filter(authors__name="John Smith") .values_list("title", flat=True) ), [], ) dive.authors.add(john) self.assertEqual( list( Book.objects.using("other") .filter(authors__name="Mark Pilgrim") .values_list("title", flat=True) ), ["Dive into Python"], ) self.assertEqual( list( Book.objects.using("other") .filter(authors__name="John Smith") .values_list("title", flat=True) ), ["Dive into Python"], ) # Remove the second author dive.authors.remove(john) self.assertEqual( list( Book.objects.using("other") .filter(authors__name="Mark Pilgrim") .values_list("title", flat=True) ), ["Dive into Python"], ) self.assertEqual( list( Book.objects.using("other") .filter(authors__name="John Smith") .values_list("title", flat=True) ), [], ) # Clear all authors dive.authors.clear() self.assertEqual( list( Book.objects.using("other") .filter(authors__name="Mark Pilgrim") .values_list("title", flat=True) ), [], ) self.assertEqual( list( Book.objects.using("other") .filter(authors__name="John Smith") .values_list("title", flat=True) ), [], ) # Create an author through the m2m interface dive.authors.create(name="Jane Brown") self.assertEqual( list( Book.objects.using("other") .filter(authors__name="Mark Pilgrim") .values_list("title", flat=True) ), [], ) self.assertEqual( list( Book.objects.using("other") .filter(authors__name="Jane Brown") .values_list("title", flat=True) ), ["Dive into Python"], ) def test_m2m_reverse_operations(self): "M2M reverse manipulations are all constrained to a single DB" # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) mark = Person.objects.using("other").create(name="Mark Pilgrim") # Save the author relations dive.authors.set([mark]) # Create a second book on the other database grease = Book.objects.using("other").create( title="Greasemonkey Hacks", published=datetime.date(2005, 11, 1) ) # Add a books to the m2m mark.book_set.add(grease) self.assertEqual( list( Person.objects.using("other") .filter(book__title="Dive into Python") .values_list("name", flat=True) ), ["Mark Pilgrim"], ) self.assertEqual( list( Person.objects.using("other") .filter(book__title="Greasemonkey Hacks") .values_list("name", flat=True) ), ["Mark Pilgrim"], ) # Remove a book from the m2m mark.book_set.remove(grease) self.assertEqual( list( Person.objects.using("other") .filter(book__title="Dive into Python") .values_list("name", flat=True) ), ["Mark Pilgrim"], ) self.assertEqual( list( Person.objects.using("other") .filter(book__title="Greasemonkey Hacks") .values_list("name", flat=True) ), [], ) # Clear the books associated with mark mark.book_set.clear() self.assertEqual( list( Person.objects.using("other") .filter(book__title="Dive into Python") .values_list("name", flat=True) ), [], ) self.assertEqual( list( Person.objects.using("other") .filter(book__title="Greasemonkey Hacks") .values_list("name", flat=True) ), [], ) # Create a book through the m2m interface mark.book_set.create( title="Dive into HTML5", published=datetime.date(2020, 1, 1) ) self.assertEqual( list( Person.objects.using("other") .filter(book__title="Dive into Python") .values_list("name", flat=True) ), [], ) self.assertEqual( list( Person.objects.using("other") .filter(book__title="Dive into HTML5") .values_list("name", flat=True) ), ["Mark Pilgrim"], ) def test_m2m_cross_database_protection(self): "Operations that involve sharing M2M objects across databases raise an error" # Create a book and author on the default database pro = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) marty = Person.objects.create(name="Marty Alchin") # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) mark = Person.objects.using("other").create(name="Mark Pilgrim") # Set a foreign key set with an object from a different database msg = ( 'Cannot assign "": the current database ' "router prevents this relation." ) with self.assertRaisesMessage(ValueError, msg): with transaction.atomic(using="default"): marty.edited.set([pro, dive]) # Add to an m2m with an object from a different database msg = ( 'Cannot add "": instance is on ' 'database "default", value is on database "other"' ) with self.assertRaisesMessage(ValueError, msg): with transaction.atomic(using="default"): marty.book_set.add(dive) # Set a m2m with an object from a different database with self.assertRaisesMessage(ValueError, msg): with transaction.atomic(using="default"): marty.book_set.set([pro, dive]) # Add to a reverse m2m with an object from a different database msg = ( 'Cannot add "": instance is on ' 'database "other", value is on database "default"' ) with self.assertRaisesMessage(ValueError, msg): with transaction.atomic(using="other"): dive.authors.add(marty) # Set a reverse m2m with an object from a different database with self.assertRaisesMessage(ValueError, msg): with transaction.atomic(using="other"): dive.authors.set([mark, marty]) def test_m2m_deletion(self): "Cascaded deletions of m2m relations issue queries on the right database" # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) mark = Person.objects.using("other").create(name="Mark Pilgrim") dive.authors.set([mark]) # Check the initial state self.assertEqual(Person.objects.using("default").count(), 0) self.assertEqual(Book.objects.using("default").count(), 0) self.assertEqual(Book.authors.through.objects.using("default").count(), 0) self.assertEqual(Person.objects.using("other").count(), 1) self.assertEqual(Book.objects.using("other").count(), 1) self.assertEqual(Book.authors.through.objects.using("other").count(), 1) # Delete the object on the other database dive.delete(using="other") self.assertEqual(Person.objects.using("default").count(), 0) self.assertEqual(Book.objects.using("default").count(), 0) self.assertEqual(Book.authors.through.objects.using("default").count(), 0) # The person still exists ... self.assertEqual(Person.objects.using("other").count(), 1) # ... but the book has been deleted self.assertEqual(Book.objects.using("other").count(), 0) # ... and the relationship object has also been deleted. self.assertEqual(Book.authors.through.objects.using("other").count(), 0) # Now try deletion in the reverse direction. Set up the relation again dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) dive.authors.set([mark]) # Check the initial state self.assertEqual(Person.objects.using("default").count(), 0) self.assertEqual(Book.objects.using("default").count(), 0) self.assertEqual(Book.authors.through.objects.using("default").count(), 0) self.assertEqual(Person.objects.using("other").count(), 1) self.assertEqual(Book.objects.using("other").count(), 1) self.assertEqual(Book.authors.through.objects.using("other").count(), 1) # Delete the object on the other database mark.delete(using="other") self.assertEqual(Person.objects.using("default").count(), 0) self.assertEqual(Book.objects.using("default").count(), 0) self.assertEqual(Book.authors.through.objects.using("default").count(), 0) # The person has been deleted ... self.assertEqual(Person.objects.using("other").count(), 0) # ... but the book still exists self.assertEqual(Book.objects.using("other").count(), 1) # ... and the relationship object has been deleted. self.assertEqual(Book.authors.through.objects.using("other").count(), 0) def test_foreign_key_separation(self): "FK fields are constrained to a single database" # Create a book and author on the default database pro = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) george = Person.objects.create(name="George Vilches") # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) chris = Person.objects.using("other").create(name="Chris Mills") # Save the author's favorite books pro.editor = george pro.save() dive.editor = chris dive.save() pro = Book.objects.using("default").get(title="Pro Django") self.assertEqual(pro.editor.name, "George Vilches") dive = Book.objects.using("other").get(title="Dive into Python") self.assertEqual(dive.editor.name, "Chris Mills") # Queries work across foreign key joins self.assertEqual( list( Person.objects.using("default") .filter(edited__title="Pro Django") .values_list("name", flat=True) ), ["George Vilches"], ) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Pro Django") .values_list("name", flat=True) ), [], ) self.assertEqual( list( Person.objects.using("default") .filter(edited__title="Dive into Python") .values_list("name", flat=True) ), [], ) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into Python") .values_list("name", flat=True) ), ["Chris Mills"], ) # Reget the objects to clear caches chris = Person.objects.using("other").get(name="Chris Mills") dive = Book.objects.using("other").get(title="Dive into Python") # Retrieve related object by descriptor. Related objects should be # database-bound. self.assertEqual( list(chris.edited.values_list("title", flat=True)), ["Dive into Python"] ) def test_foreign_key_reverse_operations(self): "FK reverse manipulations are all constrained to a single DB" dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) chris = Person.objects.using("other").create(name="Chris Mills") # Save the author relations dive.editor = chris dive.save() # Add a second book edited by chris html5 = Book.objects.using("other").create( title="Dive into HTML5", published=datetime.date(2010, 3, 15) ) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into HTML5") .values_list("name", flat=True) ), [], ) chris.edited.add(html5) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into HTML5") .values_list("name", flat=True) ), ["Chris Mills"], ) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into Python") .values_list("name", flat=True) ), ["Chris Mills"], ) # Remove the second editor chris.edited.remove(html5) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into HTML5") .values_list("name", flat=True) ), [], ) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into Python") .values_list("name", flat=True) ), ["Chris Mills"], ) # Clear all edited books chris.edited.clear() self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into HTML5") .values_list("name", flat=True) ), [], ) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into Python") .values_list("name", flat=True) ), [], ) # Create an author through the m2m interface chris.edited.create( title="Dive into Water", published=datetime.date(2010, 3, 15) ) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into HTML5") .values_list("name", flat=True) ), [], ) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into Water") .values_list("name", flat=True) ), ["Chris Mills"], ) self.assertEqual( list( Person.objects.using("other") .filter(edited__title="Dive into Python") .values_list("name", flat=True) ), [], ) def test_foreign_key_cross_database_protection(self): "Operations that involve sharing FK objects across databases raise an error" # Create a book and author on the default database pro = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) marty = Person.objects.create(name="Marty Alchin") # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) # Set a foreign key with an object from a different database msg = ( 'Cannot assign "": the current database ' "router prevents this relation." ) with self.assertRaisesMessage(ValueError, msg): dive.editor = marty # Set a foreign key set with an object from a different database with self.assertRaisesMessage(ValueError, msg): with transaction.atomic(using="default"): marty.edited.set([pro, dive]) # Add to a foreign key set with an object from a different database with self.assertRaisesMessage(ValueError, msg): with transaction.atomic(using="default"): marty.edited.add(dive) def test_foreign_key_deletion(self): """ Cascaded deletions of Foreign Key relations issue queries on the right database. """ mark = Person.objects.using("other").create(name="Mark Pilgrim") Pet.objects.using("other").create(name="Fido", owner=mark) # Check the initial state self.assertEqual(Person.objects.using("default").count(), 0) self.assertEqual(Pet.objects.using("default").count(), 0) self.assertEqual(Person.objects.using("other").count(), 1) self.assertEqual(Pet.objects.using("other").count(), 1) # Delete the person object, which will cascade onto the pet mark.delete(using="other") self.assertEqual(Person.objects.using("default").count(), 0) self.assertEqual(Pet.objects.using("default").count(), 0) # Both the pet and the person have been deleted from the right database self.assertEqual(Person.objects.using("other").count(), 0) self.assertEqual(Pet.objects.using("other").count(), 0) def test_foreign_key_validation(self): "ForeignKey.validate() uses the correct database" mickey = Person.objects.using("other").create(name="Mickey") pluto = Pet.objects.using("other").create(name="Pluto", owner=mickey) self.assertIsNone(pluto.full_clean()) # Any router that accesses `model` in db_for_read() works here. @override_settings(DATABASE_ROUTERS=[AuthRouter()]) def test_foreign_key_validation_with_router(self): """ ForeignKey.validate() passes `model` to db_for_read() even if model_instance=None. """ mickey = Person.objects.create(name="Mickey") owner_field = Pet._meta.get_field("owner") self.assertEqual(owner_field.clean(mickey.pk, None), mickey.pk) def test_o2o_separation(self): "OneToOne fields are constrained to a single database" # Create a user and profile on the default database alice = User.objects.db_manager("default").create_user( "alice", "alice@example.com" ) alice_profile = UserProfile.objects.using("default").create( user=alice, flavor="chocolate" ) # Create a user and profile on the other database bob = User.objects.db_manager("other").create_user("bob", "bob@example.com") bob_profile = UserProfile.objects.using("other").create( user=bob, flavor="crunchy frog" ) # Retrieve related objects; queries should be database constrained alice = User.objects.using("default").get(username="alice") self.assertEqual(alice.userprofile.flavor, "chocolate") bob = User.objects.using("other").get(username="bob") self.assertEqual(bob.userprofile.flavor, "crunchy frog") # Queries work across joins self.assertEqual( list( User.objects.using("default") .filter(userprofile__flavor="chocolate") .values_list("username", flat=True) ), ["alice"], ) self.assertEqual( list( User.objects.using("other") .filter(userprofile__flavor="chocolate") .values_list("username", flat=True) ), [], ) self.assertEqual( list( User.objects.using("default") .filter(userprofile__flavor="crunchy frog") .values_list("username", flat=True) ), [], ) self.assertEqual( list( User.objects.using("other") .filter(userprofile__flavor="crunchy frog") .values_list("username", flat=True) ), ["bob"], ) # Reget the objects to clear caches alice_profile = UserProfile.objects.using("default").get(flavor="chocolate") bob_profile = UserProfile.objects.using("other").get(flavor="crunchy frog") # Retrieve related object by descriptor. Related objects should be # database-bound. self.assertEqual(alice_profile.user.username, "alice") self.assertEqual(bob_profile.user.username, "bob") def test_o2o_cross_database_protection(self): "Operations that involve sharing FK objects across databases raise an error" # Create a user and profile on the default database alice = User.objects.db_manager("default").create_user( "alice", "alice@example.com" ) # Create a user and profile on the other database bob = User.objects.db_manager("other").create_user("bob", "bob@example.com") # Set a one-to-one relation with an object from a different database alice_profile = UserProfile.objects.using("default").create( user=alice, flavor="chocolate" ) msg = ( 'Cannot assign "%r": the current database router prevents this ' "relation." % alice_profile ) with self.assertRaisesMessage(ValueError, msg): bob.userprofile = alice_profile # BUT! if you assign a FK object when the base object hasn't # been saved yet, you implicitly assign the database for the # base object. bob_profile = UserProfile.objects.using("other").create( user=bob, flavor="crunchy frog" ) new_bob_profile = UserProfile(flavor="spring surprise") # assigning a profile requires an explicit pk as the object isn't saved charlie = User(pk=51, username="charlie", email="charlie@example.com") charlie.set_unusable_password() # initially, no db assigned self.assertIsNone(new_bob_profile._state.db) self.assertIsNone(charlie._state.db) # old object comes from 'other', so the new object is set to use 'other'... new_bob_profile.user = bob charlie.userprofile = bob_profile self.assertEqual(new_bob_profile._state.db, "other") self.assertEqual(charlie._state.db, "other") # ... but it isn't saved yet self.assertEqual( list(User.objects.using("other").values_list("username", flat=True)), ["bob"], ) self.assertEqual( list(UserProfile.objects.using("other").values_list("flavor", flat=True)), ["crunchy frog"], ) # When saved (no using required), new objects goes to 'other' charlie.save() bob_profile.save() new_bob_profile.save() self.assertEqual( list(User.objects.using("default").values_list("username", flat=True)), ["alice"], ) self.assertEqual( list(User.objects.using("other").values_list("username", flat=True)), ["bob", "charlie"], ) self.assertEqual( list(UserProfile.objects.using("default").values_list("flavor", flat=True)), ["chocolate"], ) self.assertEqual( list(UserProfile.objects.using("other").values_list("flavor", flat=True)), ["crunchy frog", "spring surprise"], ) # This also works if you assign the O2O relation in the constructor denise = User.objects.db_manager("other").create_user( "denise", "denise@example.com" ) denise_profile = UserProfile(flavor="tofu", user=denise) self.assertEqual(denise_profile._state.db, "other") # ... but it isn't saved yet self.assertEqual( list(UserProfile.objects.using("default").values_list("flavor", flat=True)), ["chocolate"], ) self.assertEqual( list(UserProfile.objects.using("other").values_list("flavor", flat=True)), ["crunchy frog", "spring surprise"], ) # When saved, the new profile goes to 'other' denise_profile.save() self.assertEqual( list(UserProfile.objects.using("default").values_list("flavor", flat=True)), ["chocolate"], ) self.assertEqual( list(UserProfile.objects.using("other").values_list("flavor", flat=True)), ["crunchy frog", "spring surprise", "tofu"], ) def test_generic_key_separation(self): "Generic fields are constrained to a single database" # Create a book and author on the default database pro = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) review1 = Review.objects.create(source="Python Monthly", content_object=pro) # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) review2 = Review.objects.using("other").create( source="Python Weekly", content_object=dive ) review1 = Review.objects.using("default").get(source="Python Monthly") self.assertEqual(review1.content_object.title, "Pro Django") review2 = Review.objects.using("other").get(source="Python Weekly") self.assertEqual(review2.content_object.title, "Dive into Python") # Reget the objects to clear caches dive = Book.objects.using("other").get(title="Dive into Python") # Retrieve related object by descriptor. Related objects should be # database-bound. self.assertEqual( list(dive.reviews.values_list("source", flat=True)), ["Python Weekly"] ) def test_generic_key_reverse_operations(self): "Generic reverse manipulations are all constrained to a single DB" dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) temp = Book.objects.using("other").create( title="Temp", published=datetime.date(2009, 5, 4) ) review1 = Review.objects.using("other").create( source="Python Weekly", content_object=dive ) review2 = Review.objects.using("other").create( source="Python Monthly", content_object=temp ) self.assertEqual( list( Review.objects.using("default") .filter(object_id=dive.pk) .values_list("source", flat=True) ), [], ) self.assertEqual( list( Review.objects.using("other") .filter(object_id=dive.pk) .values_list("source", flat=True) ), ["Python Weekly"], ) # Add a second review dive.reviews.add(review2) self.assertEqual( list( Review.objects.using("default") .filter(object_id=dive.pk) .values_list("source", flat=True) ), [], ) self.assertEqual( list( Review.objects.using("other") .filter(object_id=dive.pk) .values_list("source", flat=True) ), ["Python Monthly", "Python Weekly"], ) # Remove the second author dive.reviews.remove(review1) self.assertEqual( list( Review.objects.using("default") .filter(object_id=dive.pk) .values_list("source", flat=True) ), [], ) self.assertEqual( list( Review.objects.using("other") .filter(object_id=dive.pk) .values_list("source", flat=True) ), ["Python Monthly"], ) # Clear all reviews dive.reviews.clear() self.assertEqual( list( Review.objects.using("default") .filter(object_id=dive.pk) .values_list("source", flat=True) ), [], ) self.assertEqual( list( Review.objects.using("other") .filter(object_id=dive.pk) .values_list("source", flat=True) ), [], ) # Create an author through the generic interface dive.reviews.create(source="Python Daily") self.assertEqual( list( Review.objects.using("default") .filter(object_id=dive.pk) .values_list("source", flat=True) ), [], ) self.assertEqual( list( Review.objects.using("other") .filter(object_id=dive.pk) .values_list("source", flat=True) ), ["Python Daily"], ) def test_generic_key_cross_database_protection(self): """ Operations that involve sharing generic key objects across databases raise an error. """ # Create a book and author on the default database pro = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) review1 = Review.objects.create(source="Python Monthly", content_object=pro) # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) Review.objects.using("other").create( source="Python Weekly", content_object=dive ) # Set a foreign key with an object from a different database msg = ( 'Cannot assign "": the ' "current database router prevents this relation." ) with self.assertRaisesMessage(ValueError, msg): review1.content_object = dive # Add to a foreign key set with an object from a different database msg = ( " instance isn't saved. " "Use bulk=False or save the object first." ) with self.assertRaisesMessage(ValueError, msg): with transaction.atomic(using="other"): dive.reviews.add(review1) # BUT! if you assign a FK object when the base object hasn't # been saved yet, you implicitly assign the database for the # base object. review3 = Review(source="Python Daily") # initially, no db assigned self.assertIsNone(review3._state.db) # Dive comes from 'other', so review3 is set to use 'other'... review3.content_object = dive self.assertEqual(review3._state.db, "other") # ... but it isn't saved yet self.assertEqual( list( Review.objects.using("default") .filter(object_id=pro.pk) .values_list("source", flat=True) ), ["Python Monthly"], ) self.assertEqual( list( Review.objects.using("other") .filter(object_id=dive.pk) .values_list("source", flat=True) ), ["Python Weekly"], ) # When saved, John goes to 'other' review3.save() self.assertEqual( list( Review.objects.using("default") .filter(object_id=pro.pk) .values_list("source", flat=True) ), ["Python Monthly"], ) self.assertEqual( list( Review.objects.using("other") .filter(object_id=dive.pk) .values_list("source", flat=True) ), ["Python Daily", "Python Weekly"], ) def test_generic_key_deletion(self): """ Cascaded deletions of Generic Key relations issue queries on the right database. """ dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) Review.objects.using("other").create( source="Python Weekly", content_object=dive ) # Check the initial state self.assertEqual(Book.objects.using("default").count(), 0) self.assertEqual(Review.objects.using("default").count(), 0) self.assertEqual(Book.objects.using("other").count(), 1) self.assertEqual(Review.objects.using("other").count(), 1) # Delete the Book object, which will cascade onto the pet dive.delete(using="other") self.assertEqual(Book.objects.using("default").count(), 0) self.assertEqual(Review.objects.using("default").count(), 0) # Both the pet and the person have been deleted from the right database self.assertEqual(Book.objects.using("other").count(), 0) self.assertEqual(Review.objects.using("other").count(), 0) def test_ordering(self): "get_next_by_XXX commands stick to a single database" Book.objects.create(title="Pro Django", published=datetime.date(2008, 12, 16)) dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) learn = Book.objects.using("other").create( title="Learning Python", published=datetime.date(2008, 7, 16) ) self.assertEqual(learn.get_next_by_published().title, "Dive into Python") self.assertEqual(dive.get_previous_by_published().title, "Learning Python") def test_raw(self): "test the raw() method across databases" dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) val = Book.objects.db_manager("other").raw( "SELECT id FROM multiple_database_book" ) self.assertQuerySetEqual(val, [dive.pk], attrgetter("pk")) val = Book.objects.raw("SELECT id FROM multiple_database_book").using("other") self.assertQuerySetEqual(val, [dive.pk], attrgetter("pk")) def test_select_related(self): """ Database assignment is retained if an object is retrieved with select_related(). """ # Create a book and author on the other database mark = Person.objects.using("other").create(name="Mark Pilgrim") Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4), editor=mark, ) # Retrieve the Person using select_related() book = ( Book.objects.using("other") .select_related("editor") .get(title="Dive into Python") ) # The editor instance should have a db state self.assertEqual(book.editor._state.db, "other") def test_subquery(self): """Make sure as_sql works with subqueries and primary/replica.""" sub = Person.objects.using("other").filter(name="fff") qs = Book.objects.filter(editor__in=sub) # When you call __str__ on the query object, it doesn't know about using # so it falls back to the default. If the subquery explicitly uses a # different database, an error should be raised. msg = ( "Subqueries aren't allowed across different databases. Force the " "inner query to be evaluated using `list(inner_query)`." ) with self.assertRaisesMessage(ValueError, msg): str(qs.query) # Evaluating the query shouldn't work, either with self.assertRaisesMessage(ValueError, msg): for obj in qs: pass def test_related_manager(self): "Related managers return managers, not querysets" mark = Person.objects.using("other").create(name="Mark Pilgrim") # extra_arg is removed by the BookManager's implementation of # create(); but the BookManager's implementation won't get called # unless edited returns a Manager, not a queryset mark.book_set.create( title="Dive into Python", published=datetime.date(2009, 5, 4), extra_arg=True, ) mark.book_set.get_or_create( title="Dive into Python", published=datetime.date(2009, 5, 4), extra_arg=True, ) mark.edited.create( title="Dive into Water", published=datetime.date(2009, 5, 4), extra_arg=True ) mark.edited.get_or_create( title="Dive into Water", published=datetime.date(2009, 5, 4), extra_arg=True ) class ConnectionRouterTestCase(SimpleTestCase): @override_settings( DATABASE_ROUTERS=[ "multiple_database.tests.TestRouter", "multiple_database.tests.WriteRouter", ] ) def test_router_init_default(self): connection_router = ConnectionRouter() self.assertEqual( [r.__class__.__name__ for r in connection_router.routers], ["TestRouter", "WriteRouter"], ) def test_router_init_arg(self): connection_router = ConnectionRouter( [ "multiple_database.tests.TestRouter", "multiple_database.tests.WriteRouter", ] ) self.assertEqual( [r.__class__.__name__ for r in connection_router.routers], ["TestRouter", "WriteRouter"], ) # Init with instances instead of strings connection_router = ConnectionRouter([TestRouter(), WriteRouter()]) self.assertEqual( [r.__class__.__name__ for r in connection_router.routers], ["TestRouter", "WriteRouter"], ) # Make the 'other' database appear to be a replica of the 'default' @override_settings(DATABASE_ROUTERS=[TestRouter()]) class RouterTestCase(TestCase): databases = {"default", "other"} def test_db_selection(self): "Querysets obey the router for db suggestions" self.assertEqual(Book.objects.db, "other") self.assertEqual(Book.objects.all().db, "other") self.assertEqual(Book.objects.using("default").db, "default") self.assertEqual(Book.objects.db_manager("default").db, "default") self.assertEqual(Book.objects.db_manager("default").all().db, "default") def test_migrate_selection(self): "Synchronization behavior is predictable" self.assertTrue(router.allow_migrate_model("default", User)) self.assertTrue(router.allow_migrate_model("default", Book)) self.assertTrue(router.allow_migrate_model("other", User)) self.assertTrue(router.allow_migrate_model("other", Book)) with override_settings(DATABASE_ROUTERS=[TestRouter(), AuthRouter()]): # Add the auth router to the chain. TestRouter is a universal # synchronizer, so it should have no effect. self.assertTrue(router.allow_migrate_model("default", User)) self.assertTrue(router.allow_migrate_model("default", Book)) self.assertTrue(router.allow_migrate_model("other", User)) self.assertTrue(router.allow_migrate_model("other", Book)) with override_settings(DATABASE_ROUTERS=[AuthRouter(), TestRouter()]): # Now check what happens if the router order is reversed. self.assertFalse(router.allow_migrate_model("default", User)) self.assertTrue(router.allow_migrate_model("default", Book)) self.assertTrue(router.allow_migrate_model("other", User)) self.assertTrue(router.allow_migrate_model("other", Book)) def test_partial_router(self): "A router can choose to implement a subset of methods" dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) # First check the baseline behavior. self.assertEqual(router.db_for_read(User), "other") self.assertEqual(router.db_for_read(Book), "other") self.assertEqual(router.db_for_write(User), "default") self.assertEqual(router.db_for_write(Book), "default") self.assertTrue(router.allow_relation(dive, dive)) self.assertTrue(router.allow_migrate_model("default", User)) self.assertTrue(router.allow_migrate_model("default", Book)) with override_settings( DATABASE_ROUTERS=[WriteRouter(), AuthRouter(), TestRouter()] ): self.assertEqual(router.db_for_read(User), "default") self.assertEqual(router.db_for_read(Book), "other") self.assertEqual(router.db_for_write(User), "writer") self.assertEqual(router.db_for_write(Book), "writer") self.assertTrue(router.allow_relation(dive, dive)) self.assertFalse(router.allow_migrate_model("default", User)) self.assertTrue(router.allow_migrate_model("default", Book)) def test_database_routing(self): marty = Person.objects.using("default").create(name="Marty Alchin") pro = Book.objects.using("default").create( title="Pro Django", published=datetime.date(2008, 12, 16), editor=marty, ) pro.authors.set([marty]) # Create a book and author on the other database Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) # An update query will be routed to the default database Book.objects.filter(title="Pro Django").update(pages=200) with self.assertRaises(Book.DoesNotExist): # By default, the get query will be directed to 'other' Book.objects.get(title="Pro Django") # But the same query issued explicitly at a database will work. pro = Book.objects.using("default").get(title="Pro Django") # The update worked. self.assertEqual(pro.pages, 200) # An update query with an explicit using clause will be routed # to the requested database. Book.objects.using("other").filter(title="Dive into Python").update(pages=300) self.assertEqual(Book.objects.get(title="Dive into Python").pages, 300) # Related object queries stick to the same database # as the original object, regardless of the router self.assertEqual( list(pro.authors.values_list("name", flat=True)), ["Marty Alchin"] ) self.assertEqual(pro.editor.name, "Marty Alchin") # get_or_create is a special case. The get needs to be targeted at # the write database in order to avoid potential transaction # consistency problems book, created = Book.objects.get_or_create(title="Pro Django") self.assertFalse(created) book, created = Book.objects.get_or_create( title="Dive Into Python", defaults={"published": datetime.date(2009, 5, 4)} ) self.assertTrue(created) # Check the head count of objects self.assertEqual(Book.objects.using("default").count(), 2) self.assertEqual(Book.objects.using("other").count(), 1) # If a database isn't specified, the read database is used self.assertEqual(Book.objects.count(), 1) # A delete query will also be routed to the default database Book.objects.filter(pages__gt=150).delete() # The default database has lost the book. self.assertEqual(Book.objects.using("default").count(), 1) self.assertEqual(Book.objects.using("other").count(), 1) def test_invalid_set_foreign_key_assignment(self): marty = Person.objects.using("default").create(name="Marty Alchin") dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4), ) # Set a foreign key set with an object from a different database msg = ( " instance isn't saved. Use bulk=False or save the " "object first." ) with self.assertRaisesMessage(ValueError, msg): marty.edited.set([dive]) def test_foreign_key_cross_database_protection(self): "Foreign keys can cross databases if they two databases have a common source" # Create a book and author on the default database pro = Book.objects.using("default").create( title="Pro Django", published=datetime.date(2008, 12, 16) ) marty = Person.objects.using("default").create(name="Marty Alchin") # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) mark = Person.objects.using("other").create(name="Mark Pilgrim") # Set a foreign key with an object from a different database dive.editor = marty # Database assignments of original objects haven't changed... self.assertEqual(marty._state.db, "default") self.assertEqual(pro._state.db, "default") self.assertEqual(dive._state.db, "other") self.assertEqual(mark._state.db, "other") # ... but they will when the affected object is saved. dive.save() self.assertEqual(dive._state.db, "default") # ...and the source database now has a copy of any object saved Book.objects.using("default").get(title="Dive into Python").delete() # This isn't a real primary/replica database, so restore the original from other dive = Book.objects.using("other").get(title="Dive into Python") self.assertEqual(dive._state.db, "other") # Set a foreign key set with an object from a different database marty.edited.set([pro, dive], bulk=False) # Assignment implies a save, so database assignments of original # objects have changed... self.assertEqual(marty._state.db, "default") self.assertEqual(pro._state.db, "default") self.assertEqual(dive._state.db, "default") self.assertEqual(mark._state.db, "other") # ...and the source database now has a copy of any object saved Book.objects.using("default").get(title="Dive into Python").delete() # This isn't a real primary/replica database, so restore the original from other dive = Book.objects.using("other").get(title="Dive into Python") self.assertEqual(dive._state.db, "other") # Add to a foreign key set with an object from a different database marty.edited.add(dive, bulk=False) # Add implies a save, so database assignments of original objects have # changed... self.assertEqual(marty._state.db, "default") self.assertEqual(pro._state.db, "default") self.assertEqual(dive._state.db, "default") self.assertEqual(mark._state.db, "other") # ...and the source database now has a copy of any object saved Book.objects.using("default").get(title="Dive into Python").delete() # This isn't a real primary/replica database, so restore the original from other dive = Book.objects.using("other").get(title="Dive into Python") # If you assign a FK object when the base object hasn't # been saved yet, you implicitly assign the database for the # base object. chris = Person(name="Chris Mills") html5 = Book(title="Dive into HTML5", published=datetime.date(2010, 3, 15)) # initially, no db assigned self.assertIsNone(chris._state.db) self.assertIsNone(html5._state.db) # old object comes from 'other', so the new object is set to use the # source of 'other'... self.assertEqual(dive._state.db, "other") chris.save() dive.editor = chris html5.editor = mark self.assertEqual(dive._state.db, "other") self.assertEqual(mark._state.db, "other") self.assertEqual(chris._state.db, "default") self.assertEqual(html5._state.db, "default") # This also works if you assign the FK in the constructor water = Book( title="Dive into Water", published=datetime.date(2001, 1, 1), editor=mark ) self.assertEqual(water._state.db, "default") # For the remainder of this test, create a copy of 'mark' in the # 'default' database to prevent integrity errors on backends that # don't defer constraints checks until the end of the transaction mark.save(using="default") # This moved 'mark' in the 'default' database, move it back in 'other' mark.save(using="other") self.assertEqual(mark._state.db, "other") # If you create an object through a FK relation, it will be # written to the write database, even if the original object # was on the read database cheesecake = mark.edited.create( title="Dive into Cheesecake", published=datetime.date(2010, 3, 15) ) self.assertEqual(cheesecake._state.db, "default") # Same goes for get_or_create, regardless of whether getting or creating cheesecake, created = mark.edited.get_or_create( title="Dive into Cheesecake", published=datetime.date(2010, 3, 15), ) self.assertEqual(cheesecake._state.db, "default") puddles, created = mark.edited.get_or_create( title="Dive into Puddles", published=datetime.date(2010, 3, 15) ) self.assertEqual(puddles._state.db, "default") def test_m2m_cross_database_protection(self): "M2M relations can cross databases if the database share a source" # Create books and authors on the inverse to the usual database pro = Book.objects.using("other").create( pk=1, title="Pro Django", published=datetime.date(2008, 12, 16) ) marty = Person.objects.using("other").create(pk=1, name="Marty Alchin") dive = Book.objects.using("default").create( pk=2, title="Dive into Python", published=datetime.date(2009, 5, 4) ) mark = Person.objects.using("default").create(pk=2, name="Mark Pilgrim") # Now save back onto the usual database. # This simulates primary/replica - the objects exist on both database, # but the _state.db is as it is for all other tests. pro.save(using="default") marty.save(using="default") dive.save(using="other") mark.save(using="other") # We have 2 of both types of object on both databases self.assertEqual(Book.objects.using("default").count(), 2) self.assertEqual(Book.objects.using("other").count(), 2) self.assertEqual(Person.objects.using("default").count(), 2) self.assertEqual(Person.objects.using("other").count(), 2) # Set a m2m set with an object from a different database marty.book_set.set([pro, dive]) # Database assignments don't change self.assertEqual(marty._state.db, "default") self.assertEqual(pro._state.db, "default") self.assertEqual(dive._state.db, "other") self.assertEqual(mark._state.db, "other") # All m2m relations should be saved on the default database self.assertEqual(Book.authors.through.objects.using("default").count(), 2) self.assertEqual(Book.authors.through.objects.using("other").count(), 0) # Reset relations Book.authors.through.objects.using("default").delete() # Add to an m2m with an object from a different database marty.book_set.add(dive) # Database assignments don't change self.assertEqual(marty._state.db, "default") self.assertEqual(pro._state.db, "default") self.assertEqual(dive._state.db, "other") self.assertEqual(mark._state.db, "other") # All m2m relations should be saved on the default database self.assertEqual(Book.authors.through.objects.using("default").count(), 1) self.assertEqual(Book.authors.through.objects.using("other").count(), 0) # Reset relations Book.authors.through.objects.using("default").delete() # Set a reverse m2m with an object from a different database dive.authors.set([mark, marty]) # Database assignments don't change self.assertEqual(marty._state.db, "default") self.assertEqual(pro._state.db, "default") self.assertEqual(dive._state.db, "other") self.assertEqual(mark._state.db, "other") # All m2m relations should be saved on the default database self.assertEqual(Book.authors.through.objects.using("default").count(), 2) self.assertEqual(Book.authors.through.objects.using("other").count(), 0) # Reset relations Book.authors.through.objects.using("default").delete() self.assertEqual(Book.authors.through.objects.using("default").count(), 0) self.assertEqual(Book.authors.through.objects.using("other").count(), 0) # Add to a reverse m2m with an object from a different database dive.authors.add(marty) # Database assignments don't change self.assertEqual(marty._state.db, "default") self.assertEqual(pro._state.db, "default") self.assertEqual(dive._state.db, "other") self.assertEqual(mark._state.db, "other") # All m2m relations should be saved on the default database self.assertEqual(Book.authors.through.objects.using("default").count(), 1) self.assertEqual(Book.authors.through.objects.using("other").count(), 0) # If you create an object through a M2M relation, it will be # written to the write database, even if the original object # was on the read database alice = dive.authors.create(name="Alice", pk=3) self.assertEqual(alice._state.db, "default") # Same goes for get_or_create, regardless of whether getting or creating alice, created = dive.authors.get_or_create(name="Alice") self.assertEqual(alice._state.db, "default") bob, created = dive.authors.get_or_create(name="Bob", defaults={"pk": 4}) self.assertEqual(bob._state.db, "default") def test_o2o_cross_database_protection(self): "Operations that involve sharing FK objects across databases raise an error" # Create a user and profile on the default database alice = User.objects.db_manager("default").create_user( "alice", "alice@example.com" ) # Create a user and profile on the other database bob = User.objects.db_manager("other").create_user("bob", "bob@example.com") # Set a one-to-one relation with an object from a different database alice_profile = UserProfile.objects.create(user=alice, flavor="chocolate") bob.userprofile = alice_profile # Database assignments of original objects haven't changed... self.assertEqual(alice._state.db, "default") self.assertEqual(alice_profile._state.db, "default") self.assertEqual(bob._state.db, "other") # ... but they will when the affected object is saved. bob.save() self.assertEqual(bob._state.db, "default") def test_generic_key_cross_database_protection(self): "Generic Key operations can span databases if they share a source" # Create a book and author on the default database pro = Book.objects.using("default").create( title="Pro Django", published=datetime.date(2008, 12, 16) ) review1 = Review.objects.using("default").create( source="Python Monthly", content_object=pro ) # Create a book and author on the other database dive = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) review2 = Review.objects.using("other").create( source="Python Weekly", content_object=dive ) # Set a generic foreign key with an object from a different database review1.content_object = dive # Database assignments of original objects haven't changed... self.assertEqual(pro._state.db, "default") self.assertEqual(review1._state.db, "default") self.assertEqual(dive._state.db, "other") self.assertEqual(review2._state.db, "other") # ... but they will when the affected object is saved. dive.save() self.assertEqual(review1._state.db, "default") self.assertEqual(dive._state.db, "default") # ...and the source database now has a copy of any object saved Book.objects.using("default").get(title="Dive into Python").delete() # This isn't a real primary/replica database, so restore the original from other dive = Book.objects.using("other").get(title="Dive into Python") self.assertEqual(dive._state.db, "other") # Add to a generic foreign key set with an object from a different database dive.reviews.add(review1) # Database assignments of original objects haven't changed... self.assertEqual(pro._state.db, "default") self.assertEqual(review1._state.db, "default") self.assertEqual(dive._state.db, "other") self.assertEqual(review2._state.db, "other") # ... but they will when the affected object is saved. dive.save() self.assertEqual(dive._state.db, "default") # ...and the source database now has a copy of any object saved Book.objects.using("default").get(title="Dive into Python").delete() # BUT! if you assign a FK object when the base object hasn't # been saved yet, you implicitly assign the database for the # base object. review3 = Review(source="Python Daily") # initially, no db assigned self.assertIsNone(review3._state.db) # Dive comes from 'other', so review3 is set to use the source of 'other'... review3.content_object = dive self.assertEqual(review3._state.db, "default") # If you create an object through a M2M relation, it will be # written to the write database, even if the original object # was on the read database dive = Book.objects.using("other").get(title="Dive into Python") nyt = dive.reviews.create(source="New York Times", content_object=dive) self.assertEqual(nyt._state.db, "default") def test_m2m_managers(self): "M2M relations are represented by managers, and can be controlled like managers" pro = Book.objects.using("other").create( pk=1, title="Pro Django", published=datetime.date(2008, 12, 16) ) marty = Person.objects.using("other").create(pk=1, name="Marty Alchin") self.assertEqual(pro.authors.db, "other") self.assertEqual(pro.authors.db_manager("default").db, "default") self.assertEqual(pro.authors.db_manager("default").all().db, "default") self.assertEqual(marty.book_set.db, "other") self.assertEqual(marty.book_set.db_manager("default").db, "default") self.assertEqual(marty.book_set.db_manager("default").all().db, "default") def test_foreign_key_managers(self): """ FK reverse relations are represented by managers, and can be controlled like managers. """ marty = Person.objects.using("other").create(pk=1, name="Marty Alchin") Book.objects.using("other").create( pk=1, title="Pro Django", published=datetime.date(2008, 12, 16), editor=marty, ) self.assertEqual(marty.edited.db, "other") self.assertEqual(marty.edited.db_manager("default").db, "default") self.assertEqual(marty.edited.db_manager("default").all().db, "default") def test_generic_key_managers(self): """ Generic key relations are represented by managers, and can be controlled like managers. """ pro = Book.objects.using("other").create( title="Pro Django", published=datetime.date(2008, 12, 16) ) Review.objects.using("other").create( source="Python Monthly", content_object=pro ) self.assertEqual(pro.reviews.db, "other") self.assertEqual(pro.reviews.db_manager("default").db, "default") self.assertEqual(pro.reviews.db_manager("default").all().db, "default") def test_subquery(self): """Make sure as_sql works with subqueries and primary/replica.""" # Create a book and author on the other database mark = Person.objects.using("other").create(name="Mark Pilgrim") Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4), editor=mark, ) sub = Person.objects.filter(name="Mark Pilgrim") qs = Book.objects.filter(editor__in=sub) # When you call __str__ on the query object, it doesn't know about using # so it falls back to the default. Don't let routing instructions # force the subquery to an incompatible database. str(qs.query) # If you evaluate the query, it should work, running on 'other' self.assertEqual(list(qs.values_list("title", flat=True)), ["Dive into Python"]) def test_deferred_models(self): mark_def = Person.objects.using("default").create(name="Mark Pilgrim") mark_other = Person.objects.using("other").create(name="Mark Pilgrim") orig_b = Book.objects.using("other").create( title="Dive into Python", published=datetime.date(2009, 5, 4), editor=mark_other, ) b = Book.objects.using("other").only("title").get(pk=orig_b.pk) self.assertEqual(b.published, datetime.date(2009, 5, 4)) b = Book.objects.using("other").only("title").get(pk=orig_b.pk) b.editor = mark_def b.save(using="default") self.assertEqual( Book.objects.using("default").get(pk=b.pk).published, datetime.date(2009, 5, 4), ) @override_settings(DATABASE_ROUTERS=[AuthRouter()]) class AuthTestCase(TestCase): databases = {"default", "other"} def test_auth_manager(self): "The methods on the auth manager obey database hints" # Create one user using default allocation policy User.objects.create_user("alice", "alice@example.com") # Create another user, explicitly specifying the database User.objects.db_manager("default").create_user("bob", "bob@example.com") # The second user only exists on the other database alice = User.objects.using("other").get(username="alice") self.assertEqual(alice.username, "alice") self.assertEqual(alice._state.db, "other") with self.assertRaises(User.DoesNotExist): User.objects.using("default").get(username="alice") # The second user only exists on the default database bob = User.objects.using("default").get(username="bob") self.assertEqual(bob.username, "bob") self.assertEqual(bob._state.db, "default") with self.assertRaises(User.DoesNotExist): User.objects.using("other").get(username="bob") # That is... there is one user on each database self.assertEqual(User.objects.using("default").count(), 1) self.assertEqual(User.objects.using("other").count(), 1) def test_dumpdata(self): "dumpdata honors allow_migrate restrictions on the router" User.objects.create_user("alice", "alice@example.com") User.objects.db_manager("default").create_user("bob", "bob@example.com") # dumping the default database doesn't try to include auth because # allow_migrate prohibits auth on default new_io = StringIO() management.call_command( "dumpdata", "auth", format="json", database="default", stdout=new_io ) command_output = new_io.getvalue().strip() self.assertEqual(command_output, "[]") # dumping the other database does include auth new_io = StringIO() management.call_command( "dumpdata", "auth", format="json", database="other", stdout=new_io ) command_output = new_io.getvalue().strip() self.assertIn('"email": "alice@example.com"', command_output) class AntiPetRouter: # A router that only expresses an opinion on migrate, # passing pets to the 'other' database def allow_migrate(self, db, app_label, model_name=None, **hints): if db == "other": return model_name == "pet" else: return model_name != "pet" class FixtureTestCase(TestCase): databases = {"default", "other"} fixtures = ["multidb-common", "multidb"] @override_settings(DATABASE_ROUTERS=[AntiPetRouter()]) def test_fixture_loading(self): "Multi-db fixtures are loaded correctly" # "Pro Django" exists on the default database, but not on other database Book.objects.get(title="Pro Django") Book.objects.using("default").get(title="Pro Django") with self.assertRaises(Book.DoesNotExist): Book.objects.using("other").get(title="Pro Django") # "Dive into Python" exists on the default database, but not on other database Book.objects.using("other").get(title="Dive into Python") with self.assertRaises(Book.DoesNotExist): Book.objects.get(title="Dive into Python") with self.assertRaises(Book.DoesNotExist): Book.objects.using("default").get(title="Dive into Python") # "Definitive Guide" exists on the both databases Book.objects.get(title="The Definitive Guide to Django") Book.objects.using("default").get(title="The Definitive Guide to Django") Book.objects.using("other").get(title="The Definitive Guide to Django") @override_settings(DATABASE_ROUTERS=[AntiPetRouter()]) def test_pseudo_empty_fixtures(self): """ A fixture can contain entries, but lead to nothing in the database; this shouldn't raise an error (#14068). """ new_io = StringIO() management.call_command("loaddata", "pets", stdout=new_io, stderr=new_io) command_output = new_io.getvalue().strip() # No objects will actually be loaded self.assertEqual( command_output, "Installed 0 object(s) (of 2) from 1 fixture(s)" ) class PickleQuerySetTestCase(TestCase): databases = {"default", "other"} def test_pickling(self): for db in self.databases: Book.objects.using(db).create( title="Dive into Python", published=datetime.date(2009, 5, 4) ) qs = Book.objects.all() self.assertEqual(qs.db, pickle.loads(pickle.dumps(qs)).db) class DatabaseReceiver: """ Used in the tests for the database argument in signals (#13552) """ def __call__(self, signal, sender, **kwargs): self._database = kwargs["using"] class WriteToOtherRouter: """ A router that sends all writes to the other database. """ def db_for_write(self, model, **hints): return "other" class SignalTests(TestCase): databases = {"default", "other"} def override_router(self): return override_settings(DATABASE_ROUTERS=[WriteToOtherRouter()]) def test_database_arg_save_and_delete(self): """ The pre/post_save signal contains the correct database. """ # Make some signal receivers pre_save_receiver = DatabaseReceiver() post_save_receiver = DatabaseReceiver() pre_delete_receiver = DatabaseReceiver() post_delete_receiver = DatabaseReceiver() # Make model and connect receivers signals.pre_save.connect(sender=Person, receiver=pre_save_receiver) signals.post_save.connect(sender=Person, receiver=post_save_receiver) signals.pre_delete.connect(sender=Person, receiver=pre_delete_receiver) signals.post_delete.connect(sender=Person, receiver=post_delete_receiver) p = Person.objects.create(name="Darth Vader") # Save and test receivers got calls p.save() self.assertEqual(pre_save_receiver._database, DEFAULT_DB_ALIAS) self.assertEqual(post_save_receiver._database, DEFAULT_DB_ALIAS) # Delete, and test p.delete() self.assertEqual(pre_delete_receiver._database, DEFAULT_DB_ALIAS) self.assertEqual(post_delete_receiver._database, DEFAULT_DB_ALIAS) # Save again to a different database p.save(using="other") self.assertEqual(pre_save_receiver._database, "other") self.assertEqual(post_save_receiver._database, "other") # Delete, and test p.delete(using="other") self.assertEqual(pre_delete_receiver._database, "other") self.assertEqual(post_delete_receiver._database, "other") signals.pre_save.disconnect(sender=Person, receiver=pre_save_receiver) signals.post_save.disconnect(sender=Person, receiver=post_save_receiver) signals.pre_delete.disconnect(sender=Person, receiver=pre_delete_receiver) signals.post_delete.disconnect(sender=Person, receiver=post_delete_receiver) def test_database_arg_m2m(self): """ The m2m_changed signal has a correct database arg. """ # Make a receiver receiver = DatabaseReceiver() # Connect it signals.m2m_changed.connect(receiver=receiver) # Create the models that will be used for the tests b = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) p = Person.objects.create(name="Marty Alchin") # Create a copy of the models on the 'other' database to prevent # integrity errors on backends that don't defer constraints checks Book.objects.using("other").create( pk=b.pk, title=b.title, published=b.published ) Person.objects.using("other").create(pk=p.pk, name=p.name) # Test addition b.authors.add(p) self.assertEqual(receiver._database, DEFAULT_DB_ALIAS) with self.override_router(): b.authors.add(p) self.assertEqual(receiver._database, "other") # Test removal b.authors.remove(p) self.assertEqual(receiver._database, DEFAULT_DB_ALIAS) with self.override_router(): b.authors.remove(p) self.assertEqual(receiver._database, "other") # Test addition in reverse p.book_set.add(b) self.assertEqual(receiver._database, DEFAULT_DB_ALIAS) with self.override_router(): p.book_set.add(b) self.assertEqual(receiver._database, "other") # Test clearing b.authors.clear() self.assertEqual(receiver._database, DEFAULT_DB_ALIAS) with self.override_router(): b.authors.clear() self.assertEqual(receiver._database, "other") class AttributeErrorRouter: "A router to test the exception handling of ConnectionRouter" def db_for_read(self, model, **hints): raise AttributeError def db_for_write(self, model, **hints): raise AttributeError class RouterAttributeErrorTestCase(TestCase): databases = {"default", "other"} def override_router(self): return override_settings(DATABASE_ROUTERS=[AttributeErrorRouter()]) def test_attribute_error_read(self): "The AttributeError from AttributeErrorRouter bubbles up" b = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) with self.override_router(): with self.assertRaises(AttributeError): Book.objects.get(pk=b.pk) def test_attribute_error_save(self): "The AttributeError from AttributeErrorRouter bubbles up" dive = Book() dive.title = "Dive into Python" dive.published = datetime.date(2009, 5, 4) with self.override_router(): with self.assertRaises(AttributeError): dive.save() def test_attribute_error_delete(self): "The AttributeError from AttributeErrorRouter bubbles up" b = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) p = Person.objects.create(name="Marty Alchin") b.authors.set([p]) b.editor = p with self.override_router(): with self.assertRaises(AttributeError): b.delete() def test_attribute_error_m2m(self): "The AttributeError from AttributeErrorRouter bubbles up" b = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) p = Person.objects.create(name="Marty Alchin") with self.override_router(): with self.assertRaises(AttributeError): b.authors.set([p]) class ModelMetaRouter: "A router to ensure model arguments are real model classes" def db_for_write(self, model, **hints): if not hasattr(model, "_meta"): raise ValueError @override_settings(DATABASE_ROUTERS=[ModelMetaRouter()]) class RouterModelArgumentTestCase(TestCase): databases = {"default", "other"} def test_m2m_collection(self): b = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) p = Person.objects.create(name="Marty Alchin") # test add b.authors.add(p) # test remove b.authors.remove(p) # test clear b.authors.clear() # test setattr b.authors.set([p]) # test M2M collection b.delete() def test_foreignkey_collection(self): person = Person.objects.create(name="Bob") Pet.objects.create(owner=person, name="Wart") # test related FK collection person.delete() class SyncOnlyDefaultDatabaseRouter: def allow_migrate(self, db, app_label, **hints): return db == DEFAULT_DB_ALIAS class MigrateTestCase(TestCase): # Limit memory usage when calling 'migrate'. available_apps = [ "multiple_database", "django.contrib.auth", "django.contrib.contenttypes", ] databases = {"default", "other"} def test_migrate_to_other_database(self): """Regression test for #16039: migrate with --database option.""" cts = ContentType.objects.using("other").filter(app_label="multiple_database") count = cts.count() self.assertGreater(count, 0) cts.delete() management.call_command( "migrate", verbosity=0, interactive=False, database="other" ) self.assertEqual(cts.count(), count) def test_migrate_to_other_database_with_router(self): """Regression test for #16039: migrate with --database option.""" cts = ContentType.objects.using("other").filter(app_label="multiple_database") cts.delete() with override_settings(DATABASE_ROUTERS=[SyncOnlyDefaultDatabaseRouter()]): management.call_command( "migrate", verbosity=0, interactive=False, database="other" ) self.assertEqual(cts.count(), 0) class RouterUsed(Exception): WRITE = "write" def __init__(self, mode, model, hints): self.mode = mode self.model = model self.hints = hints class RouteForWriteTestCase(TestCase): databases = {"default", "other"} class WriteCheckRouter: def db_for_write(self, model, **hints): raise RouterUsed(mode=RouterUsed.WRITE, model=model, hints=hints) def override_router(self): return override_settings( DATABASE_ROUTERS=[RouteForWriteTestCase.WriteCheckRouter()] ) def test_fk_delete(self): owner = Person.objects.create(name="Someone") pet = Pet.objects.create(name="fido", owner=owner) with self.assertRaises(RouterUsed) as cm: with self.override_router(): pet.owner.delete() e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Person) self.assertEqual(e.hints, {"instance": owner}) def test_reverse_fk_delete(self): owner = Person.objects.create(name="Someone") to_del_qs = owner.pet_set.all() with self.assertRaises(RouterUsed) as cm: with self.override_router(): to_del_qs.delete() e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Pet) self.assertEqual(e.hints, {"instance": owner}) def test_reverse_fk_get_or_create(self): owner = Person.objects.create(name="Someone") with self.assertRaises(RouterUsed) as cm: with self.override_router(): owner.pet_set.get_or_create(name="fido") e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Pet) self.assertEqual(e.hints, {"instance": owner}) def test_reverse_fk_update(self): owner = Person.objects.create(name="Someone") Pet.objects.create(name="fido", owner=owner) with self.assertRaises(RouterUsed) as cm: with self.override_router(): owner.pet_set.update(name="max") e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Pet) self.assertEqual(e.hints, {"instance": owner}) def test_m2m_add(self): auth = Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) with self.assertRaises(RouterUsed) as cm: with self.override_router(): book.authors.add(auth) e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Book.authors.through) self.assertEqual(e.hints, {"instance": book}) def test_m2m_clear(self): auth = Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) book.authors.add(auth) with self.assertRaises(RouterUsed) as cm: with self.override_router(): book.authors.clear() e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Book.authors.through) self.assertEqual(e.hints, {"instance": book}) def test_m2m_delete(self): auth = Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) book.authors.add(auth) with self.assertRaises(RouterUsed) as cm: with self.override_router(): book.authors.all().delete() e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Person) self.assertEqual(e.hints, {"instance": book}) def test_m2m_get_or_create(self): Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) with self.assertRaises(RouterUsed) as cm: with self.override_router(): book.authors.get_or_create(name="Someone else") e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Book) self.assertEqual(e.hints, {"instance": book}) def test_m2m_remove(self): auth = Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) book.authors.add(auth) with self.assertRaises(RouterUsed) as cm: with self.override_router(): book.authors.remove(auth) e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Book.authors.through) self.assertEqual(e.hints, {"instance": book}) def test_m2m_update(self): auth = Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) book.authors.add(auth) with self.assertRaises(RouterUsed) as cm: with self.override_router(): book.authors.update(name="Different") e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Person) self.assertEqual(e.hints, {"instance": book}) def test_reverse_m2m_add(self): auth = Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) with self.assertRaises(RouterUsed) as cm: with self.override_router(): auth.book_set.add(book) e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Book.authors.through) self.assertEqual(e.hints, {"instance": auth}) def test_reverse_m2m_clear(self): auth = Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) book.authors.add(auth) with self.assertRaises(RouterUsed) as cm: with self.override_router(): auth.book_set.clear() e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Book.authors.through) self.assertEqual(e.hints, {"instance": auth}) def test_reverse_m2m_delete(self): auth = Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) book.authors.add(auth) with self.assertRaises(RouterUsed) as cm: with self.override_router(): auth.book_set.all().delete() e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Book) self.assertEqual(e.hints, {"instance": auth}) def test_reverse_m2m_get_or_create(self): auth = Person.objects.create(name="Someone") Book.objects.create(title="Pro Django", published=datetime.date(2008, 12, 16)) with self.assertRaises(RouterUsed) as cm: with self.override_router(): auth.book_set.get_or_create( title="New Book", published=datetime.datetime.now() ) e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Person) self.assertEqual(e.hints, {"instance": auth}) def test_reverse_m2m_remove(self): auth = Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) book.authors.add(auth) with self.assertRaises(RouterUsed) as cm: with self.override_router(): auth.book_set.remove(book) e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Book.authors.through) self.assertEqual(e.hints, {"instance": auth}) def test_reverse_m2m_update(self): auth = Person.objects.create(name="Someone") book = Book.objects.create( title="Pro Django", published=datetime.date(2008, 12, 16) ) book.authors.add(auth) with self.assertRaises(RouterUsed) as cm: with self.override_router(): auth.book_set.update(title="Different") e = cm.exception self.assertEqual(e.mode, RouterUsed.WRITE) self.assertEqual(e.model, Book) self.assertEqual(e.hints, {"instance": auth}) class NoRelationRouter: """Disallow all relations.""" def allow_relation(self, obj1, obj2, **hints): return False @override_settings(DATABASE_ROUTERS=[NoRelationRouter()]) class RelationAssignmentTests(SimpleTestCase): """allow_relation() is called with unsaved model instances.""" databases = {"default", "other"} router_prevents_msg = "the current database router prevents this relation" def test_foreign_key_relation(self): person = Person(name="Someone") pet = Pet() with self.assertRaisesMessage(ValueError, self.router_prevents_msg): pet.owner = person def test_reverse_one_to_one_relation(self): user = User(username="Someone", password="fake_hash") profile = UserProfile() with self.assertRaisesMessage(ValueError, self.router_prevents_msg): user.userprofile = profile