Files
patroni/tests/test_rewind.py
T
Alexander KukushkinandGitHub 366829e379 Refactor Connection class (#2815)
1. stop using the same cursor all the time, it creates problems when not carefully used from different threads.
2. introduce query() method in the Connection class and make it return a result set when it is possible.
3. refactor most of the code that is relying (directly or indirectly) on the Connection object to use the query() method as much as possible.

This refactoring helps with reducing code complexity and will help with future introduction of a separate database connection for the REST API thread. The last one will help to improve reliability when system is under significant stress when simple monitoring queries are taking seconds to execute and the REST API starts blocking the main thread.
2023-08-17 15:42:11 +02:00

323 lines
16 KiB
Python

from mock import Mock, PropertyMock, patch, mock_open
from patroni.postgresql import Postgresql
from patroni.postgresql.cancellable import CancellableSubprocess
from patroni.postgresql.rewind import Rewind
from . import BaseTestPostgresql, MockCursor, psycopg_connect
class MockThread(object):
def __init__(self, target, args):
self._target = target
self._args = args
def start(self):
self._target(*self._args)
def mock_cancellable_call(*args, **kwargs):
communicate = kwargs.pop('communicate', None)
if isinstance(communicate, dict):
communicate.update(stdout=b'', stderr=b'pg_rewind: error: could not open file '
+ b'"data/postgresql0/pg_xlog/000000010000000000000003": No such file')
return 1
def mock_cancellable_call0(*args, **kwargs):
communicate = kwargs.pop('communicate', None)
if isinstance(communicate, dict):
communicate.update(stdout=b'', stderr=b'')
return 0
def mock_cancellable_call1(*args, **kwargs):
communicate = kwargs.pop('communicate', None)
if isinstance(communicate, dict):
communicate.update(stdout=b'', stderr=b'')
return 1
def mock_single_user_mode(self, communicate, options):
communicate['stdout'] = b'foo'
communicate['stderr'] = b'bar'
return 1
@patch('subprocess.call', Mock(return_value=0))
@patch('patroni.psycopg.connect', psycopg_connect)
class TestRewind(BaseTestPostgresql):
def setUp(self):
super(TestRewind, self).setUp()
self.r = Rewind(self.p)
def test_can_rewind(self):
with patch.object(Postgresql, 'controldata', Mock(return_value={'wal_log_hints setting': 'on'})):
self.assertTrue(self.r.can_rewind)
with patch('subprocess.call', Mock(return_value=1)):
self.assertFalse(self.r.can_rewind)
with patch('subprocess.call', side_effect=OSError):
self.assertFalse(self.r.can_rewind)
self.p.config._config['use_pg_rewind'] = False
self.assertFalse(self.r.can_rewind)
def test_pg_rewind(self):
r = {'user': '', 'host': '', 'port': '', 'database': '', 'password': ''}
with patch.object(Postgresql, 'major_version', PropertyMock(return_value=150000)), \
patch.object(CancellableSubprocess, 'call', Mock(return_value=None)):
with patch('subprocess.check_output', Mock(return_value=b'boo')):
self.assertFalse(self.r.pg_rewind(r))
with patch('subprocess.check_output', Mock(side_effect=Exception)):
self.assertFalse(self.r.pg_rewind(r))
with patch.object(Postgresql, 'major_version', PropertyMock(return_value=120000)), \
patch('subprocess.check_output', Mock(return_value=b'foo %f %p %r %% % %')):
with patch.object(CancellableSubprocess, 'call', mock_cancellable_call):
self.assertFalse(self.r.pg_rewind(r))
with patch.object(CancellableSubprocess, 'call', mock_cancellable_call0):
self.assertTrue(self.r.pg_rewind(r))
with patch.object(CancellableSubprocess, 'call', mock_cancellable_call1):
self.assertFalse(self.r.pg_rewind(r))
@patch.object(Rewind, 'can_rewind', PropertyMock(return_value=True))
def test__get_local_timeline_lsn(self):
self.r.trigger_check_diverged_lsn()
with patch.object(Postgresql, 'controldata',
Mock(return_value={'Database cluster state': 'shut down in recovery',
'Minimum recovery ending location': '0/0',
"Min recovery ending loc's timeline": '0',
'Latest checkpoint location': '0/'})):
self.r.rewind_or_reinitialize_needed_and_possible(self.leader)
with patch.object(Postgresql, 'is_running', Mock(return_value=True)), \
patch.object(MockCursor, 'fetchone', Mock(side_effect=Exception)), \
patch.object(MockCursor, 'fetchall',
Mock(return_value=[(0, 0, 1, 1, 0, 0, 0, 0, 0, None, None, None)])):
self.r.rewind_or_reinitialize_needed_and_possible(self.leader)
@patch.object(CancellableSubprocess, 'call', mock_cancellable_call)
@patch.object(Postgresql, 'checkpoint', side_effect=['', '1'],)
@patch.object(Postgresql, 'stop', Mock(return_value=False))
@patch.object(Postgresql, 'start', Mock())
def test_execute(self, mock_checkpoint):
self.r.execute(self.leader)
with patch.object(Postgresql, 'major_version', PropertyMock(return_value=130000)):
self.r.execute(self.leader)
with patch.object(MockCursor, 'fetchone', Mock(side_effect=Exception)):
self.r.execute(self.leader)
with patch.object(Rewind, 'pg_rewind', Mock(return_value=False)):
mock_checkpoint.side_effect = ['1', '', '', '']
self.r.execute(self.leader)
self.r.execute(self.leader)
with patch.object(Rewind, 'check_leader_is_not_in_recovery', Mock(return_value=False)):
self.r.execute(self.leader)
self.p.config._config['remove_data_directory_on_rewind_failure'] = False
self.r.trigger_check_diverged_lsn()
self.r.execute(self.leader)
self.leader.member.data.update(version='1.5.7', checkpoint_after_promote=False, role='primary')
self.assertIsNone(self.r.execute(self.leader))
del self.leader.member.data['checkpoint_after_promote']
with patch.object(Rewind, 'check_leader_is_not_in_recovery', Mock(return_value=False)):
self.assertIsNone(self.r.execute(self.leader))
with patch.object(Postgresql, 'is_running', Mock(return_value=True)):
self.r.execute(self.leader)
@patch('patroni.postgresql.rewind.logger.info')
def test__log_primary_history(self, mock_logger):
history = [[n, n, ''] for n in range(1, 10)]
self.r._log_primary_history(history, 1)
expected = '\n'.join(['{0}\t0/{0}\t'.format(n) for n in range(1, 4)] + ['...', '9\t0/9\t'])
self.assertEqual(mock_logger.call_args[0][1], expected)
@patch.object(Postgresql, 'start', Mock())
@patch.object(Rewind, 'can_rewind', PropertyMock(return_value=True))
@patch.object(Rewind, '_get_local_timeline_lsn')
@patch.object(Rewind, 'check_leader_is_not_in_recovery')
def test__check_timeline_and_lsn(self, mock_check_leader_is_not_in_recovery, mock_get_local_timeline_lsn):
mock_get_local_timeline_lsn.return_value = (True, 2, 67197377)
mock_check_leader_is_not_in_recovery.return_value = False
self.r.trigger_check_diverged_lsn()
self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
self.leader = self.leader.member
self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
mock_check_leader_is_not_in_recovery.return_value = True
self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
self.r.trigger_check_diverged_lsn()
with patch.object(MockCursor, 'fetchone', Mock(side_effect=[('', 3, '0/0'), ('', b'4\t0/40159C0\tn\n')])):
self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
self.r.reset_state()
self.r.trigger_check_diverged_lsn()
with patch('patroni.psycopg.connect', Mock(side_effect=Exception)):
self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
self.r.trigger_check_diverged_lsn()
with patch.object(MockCursor, 'fetchone', Mock(side_effect=[('', 3, '0/0'), ('', b'1\t0/40159C0\tn\n')])):
self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
self.r.reset_state()
self.r.trigger_check_diverged_lsn()
with patch.object(MockCursor, 'fetchone', Mock(return_value=('', 1, '0/0'))):
with patch.object(Rewind, '_get_local_timeline_lsn', Mock(return_value=(True, 1, '0/0'))):
self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
self.r.trigger_check_diverged_lsn()
self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
self.r.reset_state()
self.r.trigger_check_diverged_lsn()
mock_get_local_timeline_lsn.return_value = (False, 2, 67296664)
self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
with patch('subprocess.Popen') as mock_popen:
mock_popen.return_value.communicate.return_value = (
b'0, lsn: 0/040159C1, prev 0/\n',
b'pg_waldump: fatal: error in WAL record at 0/40159C1: invalid record length at /: wanted 24, got 0\n'
)
self.r.reset_state()
self.r.trigger_check_diverged_lsn()
mock_get_local_timeline_lsn.return_value = (False, 2, 67197377)
self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
self.r.reset_state()
self.r.trigger_check_diverged_lsn()
mock_popen.side_effect = Exception
self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
@patch.object(MockCursor, 'fetchone', Mock(side_effect=[(True,), Exception]))
def test_check_leader_is_not_in_recovery(self):
self.r.check_leader_is_not_in_recovery({})
self.r.check_leader_is_not_in_recovery({})
def test_read_postmaster_opts(self):
m = mock_open(read_data='/usr/lib/postgres/9.6/bin/postgres "-D" "data/postgresql0" \
"--listen_addresses=127.0.0.1" "--port=5432" "--hot_standby=on" "--wal_level=hot_standby" \
"--wal_log_hints=on" "--max_wal_senders=5" "--max_replication_slots=5"\n')
with patch('builtins.open', m):
data = self.r.read_postmaster_opts()
self.assertEqual(data['wal_level'], 'hot_standby')
self.assertEqual(int(data['max_replication_slots']), 5)
self.assertEqual(data.get('D'), None)
m.side_effect = IOError
data = self.r.read_postmaster_opts()
self.assertEqual(data, dict())
@patch('psutil.Popen')
def test_single_user_mode(self, subprocess_popen_mock):
subprocess_popen_mock.return_value.wait.return_value = 0
subprocess_popen_mock.return_value.communicate.return_value = ('', '')
self.assertEqual(self.r.single_user_mode({'input': 'CHECKPOINT'}, {'archive_mode': 'on'}), 0)
@patch('os.listdir', Mock(side_effect=[OSError, ['a', 'b']]))
@patch('os.unlink', Mock(side_effect=OSError))
@patch('os.remove', Mock())
@patch('os.path.islink', Mock(side_effect=[True, False]))
@patch('os.path.isfile', Mock(return_value=True))
def test_cleanup_archive_status(self):
self.r.cleanup_archive_status()
self.r.cleanup_archive_status()
@patch('os.path.isfile', Mock(return_value=True))
@patch('shutil.move', Mock(side_effect=OSError))
@patch('patroni.postgresql.rewind.logger.info')
def test_archive_ready_wals(self, mock_logger_info):
with patch('os.listdir', Mock(side_effect=OSError)), \
patch.object(Postgresql, 'get_guc_value', Mock(side_effect=['on', 'command %f'])):
self.r._archive_ready_wals()
mock_logger_info.assert_not_called()
# each assert_not_called() calls get_guc_value('archive_mode') + get_guc_value('archive_command')
get_guc_value_res = [
'', 'command %f',
'on', '',
]
with patch.object(Postgresql, 'get_guc_value', Mock(side_effect=get_guc_value_res)):
for _ in range(len(get_guc_value_res) // 2):
self.r._archive_ready_wals()
mock_logger_info.assert_not_called()
with patch('os.listdir', Mock(return_value=['000000000000000000000000.ready'])):
# successful archive_command call
with patch.object(CancellableSubprocess, 'call', Mock(return_value=0)) as mock_subprocess_call:
get_guc_value_res = [
'on', 'command %f',
'always', 'command %f',
]
with patch.object(Postgresql, 'get_guc_value', Mock(side_effect=get_guc_value_res)):
for _ in range(len(get_guc_value_res) // 2):
self.r._archive_ready_wals()
mock_logger_info.assert_called_once()
self.assertEqual(('Trying to archive %s: %s',
'000000000000000000000000', 'command 000000000000000000000000'),
mock_logger_info.call_args[0])
mock_logger_info.reset_mock()
mock_subprocess_call.assert_called_once()
self.assertEqual(mock_subprocess_call.call_args[0][0], ['command 000000000000000000000000'])
self.assertEqual(mock_subprocess_call.call_args[1]['shell'], True)
mock_subprocess_call.reset_mock()
# failed archive_command call
with patch.object(CancellableSubprocess, 'call', Mock(return_value=1)):
with patch.object(Postgresql, 'get_guc_value', Mock(side_effect=['on', 'command %f'])):
self.r._archive_ready_wals()
self.assertEqual(('Trying to archive %s: %s',
'000000000000000000000000', 'command 000000000000000000000000'),
mock_logger_info.call_args_list[0][0])
self.assertEqual(('Failed to archive WAL segment %s', '000000000000000000000000'),
mock_logger_info.call_args_list[1][0])
mock_logger_info.reset_mock()
wal_files_to_skip = [
'000000000000000000000000.done',
'000000000000000000000001.partial.done',
'002.ready',
'U00000000000000000000001.ready',
]
with patch('os.listdir', Mock(return_value=wal_files_to_skip)):
self.r._archive_ready_wals()
mock_logger_info.assert_not_called()
@patch.object(Postgresql, 'major_version', PropertyMock(return_value=100000))
@patch('os.listdir', Mock(side_effect=[OSError, ['something', 'something_else']]))
@patch('shutil.rmtree', Mock())
@patch('patroni.postgresql.rewind.fsync_dir', Mock())
@patch('patroni.postgresql.rewind.logger.warning')
def test_maybe_clean_pg_replslot(self, mock_logger):
# failed to list pg_replslot/
self.assertIsNone(self.r._maybe_clean_pg_replslot())
mock_logger.assert_called_once()
mock_logger.reset_mock()
self.assertIsNone(self.r._maybe_clean_pg_replslot())
@patch('os.unlink', Mock())
@patch('os.listdir', Mock(return_value=[]))
@patch('os.path.isfile', Mock(return_value=True))
@patch.object(Rewind, 'read_postmaster_opts', Mock(return_value={}))
@patch.object(Rewind, 'single_user_mode', mock_single_user_mode)
def test_ensure_clean_shutdown(self):
self.assertIsNone(self.r.ensure_clean_shutdown())
@patch('patroni.postgresql.rewind.Thread', MockThread)
@patch.object(Postgresql, 'controldata')
@patch.object(Postgresql, 'checkpoint')
@patch.object(Postgresql, 'get_primary_timeline')
def test_ensure_checkpoint_after_promote(self, mock_get_primary_timeline, mock_checkpoint, mock_controldata):
mock_controldata.return_value = {"Latest checkpoint's TimeLineID": 1}
mock_get_primary_timeline.return_value = 1
self.r.ensure_checkpoint_after_promote(Mock())
self.r.reset_state()
mock_get_primary_timeline.return_value = 2
mock_checkpoint.return_value = 0
self.r.ensure_checkpoint_after_promote(Mock())
self.r.ensure_checkpoint_after_promote(Mock())
self.r.reset_state()
mock_controldata.side_effect = TypeError
mock_checkpoint.side_effect = Exception
self.r.ensure_checkpoint_after_promote(Mock())