def test_active_nodes(self):
self._add_nodes_and_assert_exists(count=3)
# Add another node from a different host
with mock.patch.object(db_hash_ring, 'CONF') as mock_conf:
mock_conf.host = 'another-host-52359446-c366'
another_host_node = self._add_nodes_and_assert_exists()[0]
# Assert all nodes are active (within 60 seconds)
self.assertEqual(4, len(db_hash_ring.get_active_nodes(
interval=60, group_name=HASH_RING_TEST_GROUP)))
# Substract 60 seconds from utcnow() and touch the nodes from
# our host
fake_utcnow = timeutils.utcnow() - datetime.timedelta(seconds=60)
with mock.patch.object(timeutils, 'utcnow') as mock_utcnow:
mock_utcnow.return_value = fake_utcnow
db_hash_ring.touch_nodes_from_host(HASH_RING_TEST_GROUP)
# Now assert that all nodes from our host are seeing as offline.
# Only the node from another host should be active
active_nodes = db_hash_ring.get_active_nodes(
interval=60, group_name=HASH_RING_TEST_GROUP)
self.assertEqual(1, len(active_nodes))
self.assertEqual(another_host_node, active_nodes[0].node_uuid)
def test_distributed_lock(self):
row_event = DistributedLockTestEvent()
self.mech_driver._nb_ovn.idl.notify_handler.watch_event(row_event)
worker_list = [self.mech_driver._nb_ovn, ]
# Create 10 fake workers
for _ in range(10):
node_uuid = uuidutils.generate_uuid()
db_hash_ring.add_node(node_uuid)
fake_driver = mock.MagicMock(node_uuid=node_uuid)
_idl = ovsdb_monitor.OvnNbIdl.from_server(
self.ovsdb_server_mgr.get_ovsdb_connection_path(),
'OVN_Northbound', fake_driver)
worker = self.useFixture(
base.ConnectionFixture(idl=_idl, timeout=10)).connection
worker.idl.notify_handler.watch_event(row_event)
worker.start()
worker_list.append(worker)
# Refresh the hash rings just in case
[worker.idl._hash_ring.refresh() for worker in worker_list]
# Assert we have 11 active workers in the ring
self.assertEqual(
11, len(db_hash_ring.get_active_nodes(
interval=ovn_const.HASH_RING_NODES_TIMEOUT)))
# Trigger the event
self.create_port()
# Wait for the event to complete
self.assertTrue(row_event.wait())
# Assert that only one worker handled the event
self.assertEqual(1, row_event.COUNTER)
def test_active_nodes_different_groups(self):
another_group = 'another_test_group'
self._add_nodes_and_assert_exists(count=3)
self._add_nodes_and_assert_exists(count=2, group_name=another_group)
active_nodes = db_hash_ring.get_active_nodes(
interval=60, group_name=HASH_RING_TEST_GROUP)
self.assertEqual(3, len(active_nodes))
for node in active_nodes:
self.assertEqual(HASH_RING_TEST_GROUP, node.group_name)
active_nodes = db_hash_ring.get_active_nodes(
interval=60, group_name=another_group)
self.assertEqual(2, len(active_nodes))
for node in active_nodes:
self.assertEqual(another_group, node.group_name)
def test_active_nodes_from_host(self):
self._add_nodes_and_assert_exists(count=3)
# Add another node from a different host
another_host_id = 'another-host-52359446-c366'
with mock.patch.object(db_hash_ring, 'CONF') as mock_conf:
mock_conf.host = another_host_id
self._add_nodes_and_assert_exists()
# Assert only the 3 nodes from this host is returned
active_nodes = db_hash_ring.get_active_nodes(interval=60,
from_host=True)
self.assertEqual(3, len(active_nodes))
self.assertNotIn(another_host_id, active_nodes)
def _load_hash_ring(self, refresh=False):
cache_timeout = timeutils.utcnow() - datetime.timedelta(
seconds=constants.HASH_RING_CACHE_TIMEOUT)
# Refresh the cache if:
# - Refreshed is forced (refresh=True)
# - Service just started (_wait_startup_before_caching)
# - Hash Ring is not yet instantiated
# - Cache has timed out
if (refresh or self._wait_startup_before_caching
or self._hash_ring is None or not self._hash_ring.nodes
or cache_timeout >= self._last_time_loaded):
nodes = db_hash_ring.get_active_nodes(
constants.HASH_RING_NODES_TIMEOUT)
self._hash_ring = hashring.HashRing(
{node.node_uuid
for node in nodes})
self._last_time_loaded = timeutils.utcnow()
def _wait_startup_before_caching(self):
# NOTE(lucasagomes): Some events are processed at the service's
# startup time and since many services may be started concurrently
# we do not want to use a cached hash ring at that point. This
# method checks if the created_at and updated_at columns from the
# nodes in the ring from this host is equal, and if so it means
# that the service just started.
# If the startup timeout already expired, there's no reason to
# keep reading from the DB. At this point this will always
# return False
if not self._cache_startup_timeout:
return False
nodes = db_hash_ring.get_active_nodes(
constants.HASH_RING_CACHE_TIMEOUT, from_host=True)
dont_cache = nodes and nodes[0].created_at == nodes[0].updated_at
if not dont_cache:
self._cache_startup_timeout = False
return dont_cache
