def test_weighted_db_selection(self):
"""
Make sure that the weights are being applied correctly by checking to
see if the rate that 'default' is selected is within 0.15 of the target
rate.
"""
def check_rate(target):
hits = {'default': 0, 'other': 0}
for i in range(1000):
hits[self.router.get_random_db()] += 1
rate = round(float(hits['default']) / float(hits['other']), 2)
self.assertTrue((target - 0.15) <= rate <= (target + 0.15),
"The 'default' rate of %s was not close enough to "
"the target rate." % rate)
# The initial target rate is 0.5, because 'default' has a weight of 1
# and 'other' has a rate of 2 - 'default' should be selected roughly
# half as much as 'other'.
check_rate(target=0.5)
settings.DATABASE_POOL = {
'default': 1,
'other': 4,
}
# Reinitialize the router with new weights
self.router = WeightedRandomRouter()
check_rate(target=0.25)
def test_relations(self):
"""
Relations should be allowed for databases in the pool and the master.
"""
settings.DATABASE_POOL = {
'other': 1,
'utility': 1,
}
self.router = WeightedRandomRouter()
# Even though default isn't in the database pool, it is the master so
# the relation should be allowed.
self.obj1._state.db = 'default'
self.obj2._state.db = 'other'
self.assertTrue(self.router.allow_relation(self.obj1, self.obj2))
def test_weighted_db_selection(self):
"""
Make sure that the weights are being applied correctly by checking to
see if the rate that 'default' is selected is within 0.15 of the target
rate.
"""
def check_rate(target):
hits = {'default': 0, 'other': 0}
for i in range(1000):
hits[self.router.get_random_db()] += 1
rate = round(float(hits['default']) / float(hits['other']), 2)
self.assertTrue((target - 0.15) <= rate <= (target + 0.15),
"The 'default' rate of %s was not close enough to "
"the target rate." % rate)
# The initial target rate is 0.5, because 'default' has a weight of 1
# and 'other' has a rate of 2 - 'default' should be selected roughly
# half as much as 'other'.
check_rate(target=0.5)
settings.DATABASE_POOL = {
'default': 1,
'other': 4,
}
# Reinitialize the router with new weights
self.router = WeightedRandomRouter()
check_rate(target=0.25)
def test_relations(self):
"""
Relations should be allowed for databases in the pool and the master.
"""
settings.DATABASE_POOL = {
'other': 1,
'utility': 1,
}
self.router = WeightedRandomRouter()
# Even though default isn't in the database pool, it is the master so
# the relation should be allowed.
self.obj1._state.db = 'default'
self.obj2._state.db = 'other'
self.assertTrue(self.router.allow_relation(self.obj1, self.obj2))
class MasterSlaveTestMixin(object):
"""A mixin for testing routers that use the MasterSlaveMixin."""
def test_writes(self):
"""Writes should always go to master."""
self.assertEqual(self.router.db_for_write(self.obj1), 'default')
def test_relations(self):
"""
Relations should be allowed for databases in the pool and the master.
"""
settings.DATABASE_POOL = {
'other': 1,
'utility': 1,
}
self.router = WeightedRandomRouter()
# Even though default isn't in the database pool, it is the master so
# the relation should be allowed.
self.obj1._state.db = 'default'
self.obj2._state.db = 'other'
self.assertTrue(self.router.allow_relation(self.obj1, self.obj2))
class MasterSlaveTestMixin(object):
"""A mixin for testing routers that use the MasterSlaveMixin."""
def test_writes(self):
"""Writes should always go to master."""
self.assertEqual(self.router.db_for_write(self.obj1), 'default')
def test_relations(self):
"""
Relations should be allowed for databases in the pool and the master.
"""
settings.DATABASE_POOL = {
'other': 1,
'utility': 1,
}
self.router = WeightedRandomRouter()
# Even though default isn't in the database pool, it is the master so
# the relation should be allowed.
self.obj1._state.db = 'default'
self.obj2._state.db = 'other'
self.assertTrue(self.router.allow_relation(self.obj1, self.obj2))
def setUp(self):
super(WeightedRandomRouterTestCase, self).setUp()
self.router = WeightedRandomRouter()
def setUp(self):
super(WeightedRandomRouterTestCase, self).setUp()
self.router = WeightedRandomRouter()
