def test_watch_stops_on_closed_connection(self):
"""Verify watches stops when the connection is closed."""
# Use a separate client connection for watching so it can be
# disconnected.
watch_client = ZookeeperClient(get_test_zookeeper_address())
yield watch_client.connect()
watch_base = StateBase(watch_client)
wait_callback = Deferred()
finish_callback = Deferred()
calls = []
def watcher(old_topology, new_topology):
calls.append((old_topology, new_topology))
wait_callback.callback(True)
return finish_callback
# Start watching.
yield watch_base._watch_topology(watcher)
# Create the topology.
topology = InternalTopology()
topology.add_machine("m-0")
yield self.set_topology(topology)
# Hold off until callback is started.
yield wait_callback
# Change the topology.
topology.add_machine("m-1")
yield self.set_topology(topology)
# Ensure that the watch has been called just once so far
# (although still pending due to the finish_callback).
self.assertEquals(len(calls), 1)
# Now disconnect the client.
watch_client.close()
self.assertFalse(watch_client.connected)
self.assertTrue(self.client.connected)
# Change the topology again.
topology.add_machine("m-2")
yield self.set_topology(topology)
# Allow the first call to be completed, starting a process of
# watching for the next change. At this point, the watch will
# encounter that the client is disconnected.
finish_callback.callback(True)
# Give a chance for something bad to happen.
yield self.poke_zk()
# Ensure the watch was still not called.
self.assertEquals(len(calls), 1)
def test_watch_stops_on_early_closed_connection(self):
"""Verify watches stops when the connection is closed early.
_watch_topology chains from an exists_and_watch to a
get_and_watch. This test ensures that this chaining will fail
gracefully if the connection is closed before this chaining
can occur.
"""
# Use a separate client connection for watching so it can be
# disconnected.
watch_client = ZookeeperClient(get_test_zookeeper_address())
yield watch_client.connect()
watch_base = StateBase(watch_client)
calls = []
@inlineCallbacks
def watcher(old_topology, new_topology):
calls.append((old_topology, new_topology))
# Create the topology.
topology = InternalTopology()
topology.add_machine("m-0")
yield self.set_topology(topology)
# Now disconnect the client.
watch_client.close()
self.assertFalse(watch_client.connected)
self.assertTrue(self.client.connected)
# Start watching.
yield watch_base._watch_topology(watcher)
# Change the topology, this will trigger the watch.
topology.add_machine("m-1")
yield self.set_topology(topology)
# Give a chance for something bad to happen.
yield self.poke_zk()
# Ensure the watcher was never called, because its client was
# disconnected.
self.assertEquals(len(calls), 0)
def setUp(self):
yield super(StateBaseTest, self).setUp()
self.base = StateBase(self.client)
