def test_router(self):
# Ham should go in the default DB:
self.assertEqual(dj_db.router.db_for_read(HamModel), "default")
# Reading one shouldn't cause it to pin:
self.assertEqual(pindb.is_pinned("default"), False)
# The delegate router has no opinion on Hams, so they should write to
# the default DB:
self.assertEqual(dj_db.router.db_for_write(HamModel), "default")
# The above should cause it to pin (even though default has no slaves
# in this case):
self.assertEqual(pindb.is_pinned("default"), True)
# Eggs are stored in a replicated DB set, so we should read from a replica:
self.assertTrue(dj_db.router.db_for_read(EggModel) in ["egg-0", "egg-1"])
# Reading shouldn't pin:
self.assertEqual(pindb.is_pinned("egg"), False)
# Writes should go to master:
self.assertEqual(dj_db.router.db_for_write(EggModel), "egg")
# And should cause a pin:
self.assertEqual(pindb.is_pinned("egg"), True)
pindb.unpin_all()
# Making a Ham should pin to the master of the default set...
ham1 = HamModel.objects.create()
self.assertEqual(pindb.is_pinned("default"), True)
# ...but not the egg set:
self.assertEqual(pindb.is_pinned("egg"), False)
# Making an Egg should pin the egg set as well:
egg1 = EggModel.objects.create()
self.assertEqual(pindb.is_pinned("egg"), True)
pindb.unpin_all()
ham1a = HamModel.objects.get(pk=ham1.pk)
egg1a = EggModel.objects.get(pk=egg1.pk) # no longer bewm
def _post_teardown(self):
"""Delete the databases after the superclass' method has closed the connections.
We must do the DB deletion in post-teardown, because that's when the
superclass closes its connection, which inadvertantly re-creates the
sqlite file if we had previously tried to delete it (like in a plain
old tearDown method).
"""
super(PinDbTestCase, self)._post_teardown()
pindb.unpin_all()
self.teardown_databases(self.old_config)
def test_misdirected_save(self):
"""Test that saves route to the right DB after a fetch.
At some point in production, we had an error that looked like fetching
a model instance (from a slave) and then saving it failed, because it
was trying to to write to the slave. It sure doesn't seem to to that
[anymore].
"""
# Set up the pre-existing model instance:
egg = EggModel.objects.create()
egg_id = egg.id
pindb.unpin_all()
egg = EggModel.objects.get(id=egg_id)
self.assertEqual(dj_db.router.db_for_write(EggModel), "egg")
def test_pinning(self):
# pinning is reflected in is_pinned
for master in settings.MASTER_DATABASES:
self.assertFalse(pindb.is_pinned(master))
pindb.pin(master)
self.assertTrue(pindb.is_pinned(master))
# unpin_all resets the state.
pindb.unpin_all()
for master in settings.MASTER_DATABASES:
self.assertFalse(pindb.is_pinned(master))
pindb.pin("default")
# pinning state is available as a set.
pinned1 = pindb.get_pinned()
self.assertTrue('default' in pinned1)
# unpinning doesn't affect the previous set.
pindb.unpin_all()
pinned2 = pindb.get_pinned()
self.assertTrue('default' in pinned1)
self.assertFalse('default' in pinned2)
# we can keep track of new pins vs. carried-over pins
# i.e. pins that stick for the replication lag period.
self.assertEqual(0, len(pindb.get_newly_pinned()))
pindb.pin("default")
self.assertEqual(1, len(pindb.get_newly_pinned()))
pindb.unpin_all()
self.assertEqual(0, len(pindb.get_newly_pinned()))
pindb.pin("default", count_as_new=False)
self.assertEqual(0, len(pindb.get_newly_pinned()))
# it counts as pinned even if we don't count it as new.
self.assertEqual(1, len(pindb.get_pinned()))
