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patroni/tests/test_ha.py
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import datetime
import etcd
import os
import pytz
import unittest
from mock import Mock, MagicMock, PropertyMock, patch
from patroni.config import Config
from patroni.dcs import Cluster, Failover, Leader, Member, get_dcs
from patroni.dcs.etcd import Client
from patroni.exceptions import DCSError, PostgresException
from patroni.ha import Ha
from patroni.postgresql import Postgresql
from test_etcd import socket_getaddrinfo, etcd_read, etcd_write, requests_get
def true(*args, **kwargs):
return True
def false(*args, **kwargs):
return False
def get_cluster(initialize, leader, members, failover):
return Cluster(initialize, None, leader, 10, members, failover)
def get_cluster_not_initialized_without_leader():
return get_cluster(None, None, [], None)
def get_cluster_initialized_without_leader(leader=False, failover=None):
m1 = Member(0, 'leader', 28, {'conn_url': 'postgres://replicator:[email protected]:5435/postgres',
'api_url': 'http://127.0.0.1:8008/patroni', 'xlog_location': 4})
l = Leader(0, 0, m1) if leader else None
m2 = Member(0, 'other', 28, {'conn_url': 'postgres://replicator:[email protected]:5436/postgres',
'api_url': 'http://127.0.0.1:8011/patroni',
'tags': {'clonefrom': True},
'scheduled_restart': {'schedule': "2100-01-01 10:53:07.560445+00:00",
'postgres_version': '99.0.0'}})
return get_cluster(True, l, [m1, m2], failover)
def get_cluster_initialized_with_leader(failover=None):
return get_cluster_initialized_without_leader(leader=True, failover=failover)
def get_cluster_initialized_with_only_leader(failover=None):
l = get_cluster_initialized_without_leader(leader=True, failover=failover).leader
return get_cluster(True, l, [l], failover)
future_restart_time = datetime.datetime.now(pytz.utc) + datetime.timedelta(days=5)
postmaster_start_time = datetime.datetime.now(pytz.utc)
class MockPatroni(object):
def __init__(self, p, d):
os.environ[Config.PATRONI_CONFIG_VARIABLE] = """
restapi:
listen: 0.0.0.0:8008
bootstrap:
users:
replicator:
password: rep-pass
options:
- replication
postgresql:
name: foo
data_dir: data/postgresql0
pg_rewind:
username: postgres
password: postgres
zookeeper:
exhibitor:
hosts: [localhost]
port: 8181
"""
self.config = Config()
self.postgresql = p
self.dcs = d
self.api = Mock()
self.tags = {'foo': 'bar'}
self.nofailover = None
self.replicatefrom = None
self.api.connection_string = 'http://127.0.0.1:8008'
self.clonefrom = None
self.scheduled_restart = {'schedule': future_restart_time,
'postmaster_start_time': str(postmaster_start_time)}
def run_async(self, func, args=()):
return func(*args) if args else func()
@patch.object(Postgresql, 'is_running', Mock(return_value=True))
@patch.object(Postgresql, 'is_leader', Mock(return_value=True))
@patch.object(Postgresql, 'xlog_position', Mock(return_value=0))
@patch.object(Postgresql, 'call_nowait', Mock(return_value=True))
@patch.object(Postgresql, 'data_directory_empty', Mock(return_value=False))
@patch.object(Postgresql, 'controldata', Mock(return_value={'Database system identifier': '1234567890'}))
@patch.object(Postgresql, 'sync_replication_slots', Mock())
@patch.object(Postgresql, 'write_pg_hba', Mock())
@patch.object(Postgresql, 'write_pgpass', Mock())
@patch.object(Postgresql, 'write_recovery_conf', Mock())
@patch.object(Postgresql, 'query', Mock())
@patch.object(Postgresql, 'checkpoint', Mock())
@patch.object(etcd.Client, 'write', etcd_write)
@patch.object(etcd.Client, 'read', etcd_read)
@patch.object(etcd.Client, 'delete', Mock(side_effect=etcd.EtcdException))
@patch('patroni.async_executor.AsyncExecutor.busy', PropertyMock(return_value=False))
@patch('patroni.async_executor.AsyncExecutor.run_async', run_async)
@patch('subprocess.call', Mock(return_value=0))
class TestHa(unittest.TestCase):
@patch('socket.getaddrinfo', socket_getaddrinfo)
@patch.object(etcd.Client, 'read', etcd_read)
def setUp(self):
with patch.object(Client, 'machines') as mock_machines:
mock_machines.__get__ = Mock(return_value=['http://remotehost:2379'])
self.p = Postgresql({'name': 'postgresql0', 'scope': 'dummy', 'listen': '127.0.0.1:5432',
'data_dir': 'data/postgresql0', 'retry_timeout': 10,
'authentication': {'superuser': {'username': 'foo', 'password': 'bar'},
'replication': {'username': '', 'password': ''}},
'parameters': {'wal_level': 'hot_standby', 'max_replication_slots': 5, 'foo': 'bar',
'hot_standby': 'on', 'max_wal_senders': 5, 'wal_keep_segments': 8}})
self.p.set_state('running')
self.p.set_role('replica')
self.p.postmaster_start_time = MagicMock(return_value=str(postmaster_start_time))
self.p.check_replication_lag = true
self.p.can_create_replica_without_replication_connection = MagicMock(return_value=False)
self.e = get_dcs({'etcd': {'ttl': 30, 'host': 'ok:2379', 'scope': 'test',
'name': 'foo', 'retry_timeout': 10}})
self.ha = Ha(MockPatroni(self.p, self.e))
self.ha.old_cluster = self.e.get_cluster()
self.ha.cluster = get_cluster_not_initialized_without_leader()
self.ha.load_cluster_from_dcs = Mock()
def test_update_lock(self):
self.p.last_operation = Mock(side_effect=PostgresException(''))
self.assertTrue(self.ha.update_lock())
def test_touch_member(self):
self.p.xlog_position = Mock(side_effect=Exception)
self.ha.touch_member()
def test_start_as_replica(self):
self.p.is_healthy = false
self.assertEquals(self.ha.run_cycle(), 'starting as a secondary')
def test_recover_replica_failed(self):
self.p.controldata = lambda: {'Database cluster state': 'in production'}
self.p.is_healthy = false
self.p.is_running = false
self.p.follow = false
self.assertEquals(self.ha.run_cycle(), 'starting as a secondary')
self.assertEquals(self.ha.run_cycle(), 'failed to start postgres')
def test_recover_master_failed(self):
self.p.follow = false
self.p.is_healthy = false
self.p.is_running = false
self.p.name = 'leader'
self.p.set_role('master')
self.p.controldata = lambda: {'Database cluster state': 'in production'}
self.ha.cluster = get_cluster_initialized_with_leader()
self.assertEquals(self.ha.run_cycle(), 'starting as readonly because i had the session lock')
def test_do_not_recover_in_pause(self):
pass
@patch('sys.exit', return_value=1)
@patch('patroni.ha.Ha.sysid_valid', MagicMock(return_value=True))
def test_sysid_no_match(self, exit_mock):
self.ha.run_cycle()
exit_mock.assert_called_once_with(1)
@patch.object(Cluster, 'is_unlocked', Mock(return_value=False))
def test_start_as_readonly(self):
self.p.is_leader = false
self.p.is_healthy = true
self.ha.has_lock = true
self.assertEquals(self.ha.run_cycle(), 'promoted self to leader because i had the session lock')
def test_acquire_lock_as_master(self):
self.assertEquals(self.ha.run_cycle(), 'acquired session lock as a leader')
def test_promoted_by_acquiring_lock(self):
self.ha.is_healthiest_node = true
self.p.is_leader = false
self.assertEquals(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
def test_demote_after_failing_to_obtain_lock(self):
self.ha.acquire_lock = false
self.assertEquals(self.ha.run_cycle(), 'demoted self after trying and failing to obtain lock')
def test_follow_new_leader_after_failing_to_obtain_lock(self):
self.ha.is_healthiest_node = true
self.ha.acquire_lock = false
self.p.is_leader = false
self.assertEquals(self.ha.run_cycle(), 'following new leader after trying and failing to obtain lock')
def test_demote_because_not_healthiest(self):
self.ha.is_healthiest_node = false
self.assertEquals(self.ha.run_cycle(), 'demoting self because i am not the healthiest node')
def test_follow_new_leader_because_not_healthiest(self):
self.ha.is_healthiest_node = false
self.p.is_leader = false
self.assertEquals(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
def test_promote_because_have_lock(self):
self.ha.cluster.is_unlocked = false
self.ha.has_lock = true
self.p.is_leader = false
self.assertEquals(self.ha.run_cycle(), 'promoted self to leader because i had the session lock')
def test_leader_with_lock(self):
self.ha.cluster.is_unlocked = false
self.ha.has_lock = true
self.assertEquals(self.ha.run_cycle(), 'no action. i am the leader with the lock')
def test_demote_because_not_having_lock(self):
self.ha.cluster.is_unlocked = false
self.assertEquals(self.ha.run_cycle(), 'demoting self because i do not have the lock and i was a leader')
def test_demote_because_update_lock_failed(self):
self.ha.cluster.is_unlocked = false
self.ha.has_lock = true
self.ha.update_lock = false
self.assertEquals(self.ha.run_cycle(), 'demoting self because i do not have the lock and i was a leader')
def test_follow(self):
self.ha.cluster.is_unlocked = false
self.p.is_leader = false
self.assertEquals(self.ha.run_cycle(), 'no action. i am a secondary and i am following a leader')
self.ha.patroni.replicatefrom = "foo"
self.assertEquals(self.ha.run_cycle(), 'no action. i am a secondary and i am following a leader')
def test_follow_in_pause(self):
self.ha.cluster.is_unlocked = false
self.ha.is_paused = true
self.assertEquals(self.ha.run_cycle(), 'PAUSE: continue to run as master without lock')
self.p.is_leader = false
self.assertEquals(self.ha.run_cycle(), 'PAUSE: no action')
def test_no_etcd_connection_master_demote(self):
self.ha.load_cluster_from_dcs = Mock(side_effect=DCSError('Etcd is not responding properly'))
self.assertEquals(self.ha.run_cycle(), 'demoted self because DCS is not accessible and i was a leader')
def test_bootstrap_from_another_member(self):
self.ha.cluster = get_cluster_initialized_with_leader()
self.assertEquals(self.ha.bootstrap(), 'trying to bootstrap from replica \'other\'')
def test_bootstrap_waiting_for_leader(self):
self.ha.cluster = get_cluster_initialized_without_leader()
self.assertEquals(self.ha.bootstrap(), 'waiting for leader to bootstrap')
def test_bootstrap_without_leader(self):
self.ha.cluster = get_cluster_initialized_without_leader()
self.p.can_create_replica_without_replication_connection = MagicMock(return_value=True)
self.assertEquals(self.ha.bootstrap(), 'trying to bootstrap (without leader)')
def test_bootstrap_initialize_lock_failed(self):
self.ha.cluster = get_cluster_not_initialized_without_leader()
self.assertEquals(self.ha.bootstrap(), 'failed to acquire initialize lock')
def test_bootstrap_initialized_new_cluster(self):
self.ha.cluster = get_cluster_not_initialized_without_leader()
self.e.initialize = true
self.assertEquals(self.ha.bootstrap(), 'initialized a new cluster')
def test_bootstrap_release_initialize_key_on_failure(self):
self.ha.cluster = get_cluster_not_initialized_without_leader()
self.e.initialize = true
self.p.bootstrap = Mock(side_effect=PostgresException("Could not bootstrap master PostgreSQL"))
self.assertRaises(PostgresException, self.ha.bootstrap)
def test_reinitialize(self):
self.assertIsNotNone(self.ha.reinitialize())
self.ha.cluster = get_cluster_initialized_with_leader()
self.assertIsNone(self.ha.reinitialize())
self.assertIsNotNone(self.ha.reinitialize())
self.ha.state_handler.name = self.ha.cluster.leader.name
self.assertIsNotNone(self.ha.reinitialize())
def test_restart(self):
self.assertEquals(self.ha.restart(), (True, 'restarted successfully'))
self.p.restart = false
self.assertEquals(self.ha.restart(), (False, 'restart failed'))
self.ha.cluster = get_cluster_initialized_with_leader()
self.ha.reinitialize()
self.assertEquals(self.ha.restart(), (False, 'reinitialize already in progress'))
with patch.object(self.ha, "restart_matches", return_value=False):
self.assertEquals(self.ha.restart({'foo': 'bar'}), (False, "restart conditions are not satisfied"))
def test_restart_in_progress(self):
with patch('patroni.async_executor.AsyncExecutor.busy', PropertyMock(return_value=True)):
self.ha.restart(run_async=True)
self.assertTrue(self.ha.restart_scheduled())
self.assertEquals(self.ha.run_cycle(), 'not healthy enough for leader race')
self.ha.cluster = get_cluster_initialized_with_leader()
self.assertEquals(self.ha.run_cycle(), 'restart in progress')
self.ha.has_lock = true
self.assertEquals(self.ha.run_cycle(), 'updated leader lock during restart')
self.ha.update_lock = false
self.assertEquals(self.ha.run_cycle(), 'failed to update leader lock during restart')
@patch('requests.get', requests_get)
@patch('time.sleep', Mock())
def test_manual_failover_from_leader(self):
self.ha.has_lock = true
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', '', None))
self.assertEquals(self.ha.run_cycle(), 'no action. i am the leader with the lock')
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', self.p.name, None))
self.assertEquals(self.ha.run_cycle(), 'no action. i am the leader with the lock')
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', 'blabla', None))
self.assertEquals(self.ha.run_cycle(), 'no action. i am the leader with the lock')
f = Failover(0, self.p.name, '', None)
self.ha.cluster = get_cluster_initialized_with_leader(f)
self.assertEquals(self.ha.run_cycle(), 'manual failover: demoting myself')
self.ha.fetch_node_status = lambda e: (e, True, True, 0, {'nofailover': 'True'})
self.assertEquals(self.ha.run_cycle(), 'no action. i am the leader with the lock')
# manual failover from the previous leader to us won't happen if we hold the nofailover flag
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, None))
self.assertEquals(self.ha.run_cycle(), 'no action. i am the leader with the lock')
# Failover scheduled time must include timezone
scheduled = datetime.datetime.now()
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
self.ha.run_cycle()
scheduled = datetime.datetime.utcnow().replace(tzinfo=pytz.UTC)
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
self.assertEquals('no action. i am the leader with the lock', self.ha.run_cycle())
scheduled = scheduled + datetime.timedelta(seconds=30)
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
self.assertEquals('no action. i am the leader with the lock', self.ha.run_cycle())
scheduled = scheduled + datetime.timedelta(seconds=-600)
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
self.assertEquals('no action. i am the leader with the lock', self.ha.run_cycle())
scheduled = None
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
self.assertEquals('no action. i am the leader with the lock', self.ha.run_cycle())
@patch('requests.get', requests_get)
def test_manual_failover_from_leader_in_pause(self):
self.ha.has_lock = true
self.ha.is_paused = true
scheduled = datetime.datetime.now()
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
self.assertEquals('PAUSE: no action. i am the leader with the lock', self.ha.run_cycle())
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, '', None))
self.assertEquals('PAUSE: no action. i am the leader with the lock', self.ha.run_cycle())
@patch('requests.get', requests_get)
@patch('time.sleep', Mock())
def test_manual_failover_process_no_leader(self):
self.p.is_leader = false
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', self.p.name, None))
self.assertEquals(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'leader', None))
self.p.set_role('replica')
self.assertEquals(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
self.ha.fetch_node_status = lambda e: (e, True, True, 0, {}) # accessible, in_recovery
self.assertEquals(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, self.p.name, '', None))
self.assertEquals(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
self.ha.fetch_node_status = lambda e: (e, False, True, 0, {}) # inaccessible, in_recovery
self.p.set_role('replica')
self.assertEquals(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
# set failover flag to True for all members of the cluster
# this should elect the current member, as we are not going to call the API for it.
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'other', None))
self.ha.fetch_node_status = lambda e: (e, True, True, 0, {'nofailover': 'True'}) # accessible, in_recovery
self.p.set_role('replica')
self.assertEquals(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
# same as previous, but set the current member to nofailover. In no case it should be elected as a leader
self.ha.patroni.nofailover = True
self.assertEquals(self.ha.run_cycle(), 'following a different leader because I am not allowed to promote')
@patch('time.sleep', Mock())
def test_manual_failover_process_no_leader_in_pause(self):
self.ha.is_paused = true
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'other', None))
self.assertEquals(self.ha.run_cycle(), 'PAUSE: continue to run as master without lock')
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', '', None))
self.assertEquals(self.ha.run_cycle(), 'PAUSE: continue to run as master without lock')
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', 'blabla', None))
self.assertEquals('PAUSE: acquired session lock as a leader', self.ha.run_cycle())
self.p.is_leader = false
self.p.set_role('replica')
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', self.p.name, None))
self.assertEquals(self.ha.run_cycle(), 'PAUSE: promoted self to leader by acquiring session lock')
def test_is_healthiest_node(self):
self.ha.state_handler.is_leader = false
self.ha.patroni.nofailover = False
self.ha.fetch_node_status = lambda e: (e, True, True, 0, {})
self.assertTrue(self.ha.is_healthiest_node())
self.ha.is_paused = true
self.assertFalse(self.ha.is_healthiest_node())
def test__is_healthiest_node(self):
self.assertTrue(self.ha._is_healthiest_node(self.ha.old_cluster.members))
self.p.is_leader = false
self.ha.fetch_node_status = lambda e: (e, True, True, 0, {}) # accessible, in_recovery
self.assertTrue(self.ha._is_healthiest_node(self.ha.old_cluster.members))
self.ha.fetch_node_status = lambda e: (e, True, False, 0, {}) # accessible, not in_recovery
self.assertFalse(self.ha._is_healthiest_node(self.ha.old_cluster.members))
self.ha.fetch_node_status = lambda e: (e, True, True, 1, {}) # accessible, in_recovery, xlog location ahead
self.assertFalse(self.ha._is_healthiest_node(self.ha.old_cluster.members))
self.p.check_replication_lag = false
self.assertFalse(self.ha._is_healthiest_node(self.ha.old_cluster.members))
self.ha.patroni.nofailover = True
self.assertFalse(self.ha._is_healthiest_node(self.ha.old_cluster.members))
self.ha.patroni.nofailover = False
@patch('requests.get', requests_get)
def test_fetch_node_status(self):
member = Member(0, 'test', 1, {'api_url': 'http://127.0.0.1:8011/patroni'})
self.ha.fetch_node_status(member)
member = Member(0, 'test', 1, {'api_url': 'http://localhost:8011/patroni'})
self.ha.fetch_node_status(member)
def test_post_recover(self):
self.p.is_running = false
self.ha.has_lock = true
self.assertEqual(self.ha.post_recover(), 'removed leader key after trying and failing to start postgres')
self.ha.has_lock = false
self.assertEqual(self.ha.post_recover(), 'failed to start postgres')
self.p.is_running = true
self.assertIsNone(self.ha.post_recover())
def test_schedule_future_restart(self):
self.ha.patroni.scheduled_restart = {}
# do the restart 2 times. The first one should succeed, the second one should fail
self.assertTrue(self.ha.schedule_future_restart({'schedule': future_restart_time}))
self.assertFalse(self.ha.schedule_future_restart({'schedule': future_restart_time}))
def test_delete_future_restarts(self):
self.ha.delete_future_restart()
def test_evaluate_scheduled_restart(self):
self.p.postmaster_start_time = Mock(return_value=str(postmaster_start_time))
# restart while the postmaster has been already restarted, fails
with patch.object(self.ha,
'future_restart_scheduled',
Mock(return_value={'postmaster_start_time':
str(postmaster_start_time - datetime.timedelta(days=1)),
'schedule': str(future_restart_time)})):
self.assertIsNone(self.ha.evaluate_scheduled_restart())
with patch.object(self.ha,
'future_restart_scheduled',
Mock(return_value={'postmaster_start_time': str(postmaster_start_time),
'schedule': str(future_restart_time)})):
with patch.object(self.ha,
'should_run_scheduled_action', Mock(return_value=True)):
# restart in the future, ok
self.assertIsNotNone(self.ha.evaluate_scheduled_restart())
with patch.object(self.ha, 'restart', Mock(return_value=(False, "Test"))):
# restart in the future, bit the actual restart failed
self.assertIsNone(self.ha.evaluate_scheduled_restart())
def test_scheduled_restart(self):
self.ha.cluster = get_cluster_initialized_with_leader()
with patch.object(self.ha, "evaluate_scheduled_restart", Mock(return_value="restart scheduled")):
self.assertEquals(self.ha.run_cycle(), "restart scheduled")
def test_restart_matches(self):
self.p._role = 'replica'
self.p.server_version = 90500
self.p._pending_restart = True
self.assertFalse(self.ha.restart_matches("master", "9.5.0", True))
self.assertFalse(self.ha.restart_matches("replica", "9.4.3", True))
self.p._pending_restart = False
self.assertFalse(self.ha.restart_matches("replica", "9.5.2", True))
self.assertTrue(self.ha.restart_matches("replica", "9.5.2", False))
def test_process_healthy_cluster_in_pause(self):
self.p.is_leader = false
self.ha.is_paused = true
self.p.name = 'leader'
self.ha.cluster = get_cluster_initialized_with_leader()
self.assertEquals(self.ha.run_cycle(), 'PAUSE: removed leader lock because postgres is not running as master')
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', self.p.name, None))
self.assertEquals(self.ha.run_cycle(), 'PAUSE: waiting to become master after promote...')
def test_postgres_unhealthy_in_pause(self):
self.ha.is_paused = true
self.p.is_healthy = false
self.assertEquals(self.ha.run_cycle(), 'PAUSE: postgres is not running')
self.ha.has_lock = true
self.assertEquals(self.ha.run_cycle(), 'PAUSE: removed leader lock because postgres is not running')
def test_no_etcd_connection_in_pause(self):
self.ha.is_paused = true
self.ha.load_cluster_from_dcs = Mock(side_effect=DCSError('Etcd is not responding properly'))
self.assertEquals(self.ha.run_cycle(), 'PAUSE: DCS is not accessible')
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