gitops/patroni
1
0
Fork 0
mirror of https://github.com/outbackdingo/patroni.git synced 2026-08-25 14:53:37 +00:00
Code Issues Packages Projects Releases Wiki Activity

Ensure strict failover/switchover definition difference (#2784)

Browse Source 
- Don't set leader in failover key from patronictl failover
- Show warning and execute switchover if leader option is provided for patronictl failover command
- Be more precise in the log messages
- Allow to failover to an async candidate in sync mode
- Check if candidate is the same as the leader specified in api
- Fix and extend some tests
- Add documentation
This commit is contained in:
Polina Bungina
2023-09-12 08:51:17 +02:00
committed by GitHub
parent 3c24c33e59
commit b31a4d55c9
8 changed files with 673 additions and 262 deletions
Download Patch File Download Diff File Expand all files Collapse all files
docs/pause.rst
+1 -1
View File
@@ -19,7 +19,7 @@ When Patroni runs in a paused mode, it does not change the state of PostgreSQL,
- For the Postgres primary with the leader lock Patroni updates the lock. If the node with the leader lock stops being the primary (i.e. is demoted manually), Patroni will release the lock instead of promoting the node back.
- Manual unscheduled restart, reinitialize and manual failover are allowed. Manual failover is only allowed if the node to failover to is specified. In the paused mode, manual failover does not require a running primary node.
- Manual unscheduled restart, manual unscheduled failover/switchover and reinitialize are allowed. No scheduled action is allowed. Manual switchover is only allowed if the node to switch over to is specified.
- If 'parallel' primaries are detected by Patroni, it emits a warning, but does not demote the primary without the leader lock.
docs/rest_api.rst
+87 -15
View File
@@ -560,39 +560,111 @@ The above call removes ``postgresql.parameters.max_connections`` from the dynami
Switchover and failover endpoints
---------------------------------
``POST /switchover`` or ``POST /failover``. These endpoints are very similar to each other. There are a couple of minor differences though:
.. _switchover_api:
1. The failover endpoint allows to perform a manual failover when there are no healthy nodes, but at the same time it will not allow you to schedule a switchover.
Switchover
^^^^^^^^^^
2. The switchover endpoint is the opposite. It works only when the cluster is healthy (there is a leader) and allows to schedule a switchover at a given time.
``/switchover`` endpoint only works when the cluster is healthy (there is a leader). It also allows to schedule a switchover at a given time.
When calling ``/switchover`` endpoint a candidate can be specified but is not required, in contrast to ``/failover`` endpoint. If a candidate is not provided, all the eligible nodes of the cluster will participate in the leader race after the leader stepped down.
In the JSON body of the ``POST`` request you must specify at least the ``leader`` or ``candidate`` fields and optionally the ``scheduled_at`` field if you want to schedule a switchover at a specific time.
In the JSON body of the ``POST`` request you must specify the ``leader`` field. The ``candidate`` and the ``scheduled_at`` fields are optional and can be used to schedule a switchover at a specific time.
Depending on the situation, requests might return different HTTP status codes and bodies. Status code **200** is returned when the switchover or failover successfully completed. If the switchover was successfully scheduled, Patroni will return HTTP status code **202**. In case something went wrong, the error status code (one of **400**, **412**, or **503**) will be returned with some details in the response body.
Example: perform a failover to the specific node:
``DELETE /switchover`` can be used to delete the currently scheduled switchover.
**Example:** perform a switchover to any healthy standby
.. code-block:: bash
$ curl -s http://localhost:8009/failover -XPOST -d '{"candidate":"postgresql1"}'
Successfully failed over to "postgresql1"
$ curl -s http://localhost:8008/switchover -XPOST -d '{"leader":"postgresql1"}'
Successfully switched over to "postgresql2"
Example: schedule a switchover from the leader to any other healthy replica in the cluster at a specific time:
**Example:** perform a switchover to a specific node
.. code-block:: bash
$ curl -s http://localhost:8008/switchover -XPOST -d \
'{"leader":"postgresql0","scheduled_at":"2019-09-24T12:00+00"}'
Switchover scheduled
$ curl -s http://localhost:8008/switchover -XPOST -d \
'{"leader":"postgresql1","candidate":"postgresql2"}'
Successfully switched over to "postgresql2"
Depending on the situation the request might finish with a different HTTP status code and body. The status code **200** is returned when the switchover or failover successfully completed. If the switchover was successfully scheduled, Patroni will return HTTP status code **202**. In case something went wrong, the error status code (one of **400**, **412** or **503**) will be returned with some details in the response body. For more information please check the source code of ``patroni/api.py:do_POST_failover()`` method.
**Example:** schedule a switchover from the leader to any other healthy standby in the cluster at a specific time.
- ``DELETE /switchover``: delete the scheduled switchover
.. code-block:: bash
The ``POST /switchover`` and ``POST failover`` endpoints are used by ``patronictl switchover`` and ``patronictl failover``, respectively.
The ``DELETE /switchover`` is used by ``patronictl flush <cluster-name> switchover``.
$ curl -s http://localhost:8008/switchover -XPOST -d \
'{"leader":"postgresql0","scheduled_at":"2019-09-24T12:00+00"}'
Switchover scheduled
Failover
^^^^^^^^
``/failover`` endpoint can be used to perform a manual failover when there are no healthy nodes (e.g. to an asynchronous standby if all synchronous standbys are not healthy enough to promote). However there is no requirement for a cluster not to have leader - failover can also be run on a healthy cluster.
In the JSON body of the ``POST`` request you must specify the ``candidate`` field. If the ``leader`` field is specified, a switchover is triggered instead.
**Example:**
.. code-block:: bash
$ curl -s http://localhost:8008/failover -XPOST -d '{"candidate":"postgresql1"}'
Successfully failed over to "postgresql1"
.. warning::
:ref:`Be very careful <failover_healthcheck>` when using this endpoint, as this can cause data loss in certain situations. In most cases, :ref:`the switchover endpoint <switchover_api>` satisfies the administrator's needs.
``POST /switchover`` and ``POST /failover`` endpoints are used by ``patronictl switchover`` and ``patronictl failover``, respectively.
``DELETE /switchover`` is used by ``patronictl flush <cluster-name> switchover``.
.. list-table:: Failover/Switchover comparison
:widths: 25 25 25
:header-rows: 1
* -
- Failover
- Switchover
* - Requires leader specified
- no
- yes
* - Requires candidate specified
- yes
- no
* - Can be run in pause
- yes
- yes (only to a specific candidate)
* - Can be scheduled
- no
- yes (if not in pause)
.. _failover_healthcheck:
Healthy standby
^^^^^^^^^^^^^^^
There are a couple of checks that a member of a cluster should pass to be able to participate in the leader race during a switchover or to become a leader as a failover/switchover candidate:
- be reachable via Patroni API;
- not have ``nofailover`` tag set to ``true``;
- have watchdog fully functional (if required by the configuration);
- in case of a switchover in a healthy cluster or an automatic failover, not exceed maximum replication lag (``maximum_lag_on_failover`` :ref:`configuration parameter <dynamic_configuration>`);
- in case of a switchover in a healthy cluster or an automatic failover, not have a timeline number smaller than the cluster timeline if ``check_timeline`` :ref:`configuration parameter <dynamic_configuration>` is set to ``true``;
- in :ref:`synchronous mode <synchronous_mode>`:
- In case of a switchover (both with and without a candidate): be listed in the ``/sync`` key members;
- For a failover in both healthy and unhealthy clusters, this check is omitted.
.. warning::
In case of a manual failover in a cluster without a leader, a candidate will be allowed to promote even if:
- it is not in the ``/sync`` key members when synchronous mode is enabled;
- its lag exceeds the maximum replication lag allowed;
- it has the timeline number smaller than the last known cluster timeline.
Restart endpoint
patroni/api.py
+16 -8
View File
@@ -1074,7 +1074,8 @@ class RestApiHandler(BaseHTTPRequestHandler):
* ``412``: if operation is not possible;
* ``503``: if unable to register the operation to the DCS;
* HTTP status returned by :func:`parse_schedule`, if any error was observed while parsing the schedule;
* HTTP status returned by :func:`poll_failover_result` if the operation has been processed immediately.
* HTTP status returned by :func:`poll_failover_result` if the operation has been processed immediately;
* ``400``: if none of the above applies.
.. note::
If unable to parse the request body, then the request is silently discarded.
@@ -1101,15 +1102,22 @@ class RestApiHandler(BaseHTTPRequestHandler):
data = 'Switchover could be performed only from a specific leader'
if not data and scheduled_at:
if not leader:
data = 'Scheduled {0} is possible only from a specific leader'.format(action)
if not data and global_config.is_paused:
data = "Can't schedule {0} in the paused state".format(action)
if not data:
if action == 'failover':
data = "Failover can't be scheduled"
elif global_config.is_paused:
data = "Can't schedule switchover in the paused state"
else:
(status_code, data, scheduled_at) = self.parse_schedule(scheduled_at, action)
if not data and global_config.is_paused and not candidate:
data = action.title() + ' is possible only to a specific candidate in a paused state'
data = 'Switchover is possible only to a specific candidate in a paused state'
if action == 'failover' and leader:
logger.warning('received failover request with leader specifed - performing switchover instead')
action = 'switchover'
if not data and leader == candidate:
data = 'Switchover target and source are the same'
if not data and not scheduled_at:
data = self.is_failover_possible(cluster, leader, candidate, action)
@@ -1126,7 +1134,7 @@ class RestApiHandler(BaseHTTPRequestHandler):
status_code, data = self.poll_failover_result(cluster.leader and cluster.leader.name,
candidate, action)
else:
data = 'failed to write {0} key into DCS'.format(action)
data = 'failed to write failover key into DCS'
status_code = 503
# pyright thinks ``status_code`` can be ``None`` because ``parse_schedule`` call may return ``None``. However,
# if that's the case, ``status_code`` will be overwritten somewhere between ``parse_schedule`` and
patroni/ctl.py
+45 -27
View File
@@ -46,6 +46,7 @@ try:
except ImportError: # pragma: no cover
from cdiff import markup_to_pager, PatchStream # pyright: ignore [reportMissingModuleSource]
from .config import Config, get_global_config
from .dcs import get_dcs as _get_dcs, AbstractDCS, Cluster, Member
from .exceptions import PatroniException
from .postgresql.misc import postgres_version_to_int
@@ -225,8 +226,6 @@ def load_config(path: str, dcs_url: Optional[str]) -> Dict[str, Any]:
:raises:
:class:`PatroniCtlException`: if *path* does not exist or is not readable.
"""
from patroni.config import Config
if not (os.path.exists(path) and os.access(path, os.R_OK)):
if path != CONFIG_FILE_PATH: # bail if non-default config location specified but file not found / readable
raise PatroniCtlException('Provided config file {0} not existing or no read rights.'
@@ -1013,7 +1012,6 @@ def reload(obj: Dict[str, Any], cluster_name: str, member_names: List[str],
if r.status == 200:
click.echo('No changes to apply on member {0}'.format(member.name))
elif r.status == 202:
from patroni.config import get_global_config
config = get_global_config(cluster)
click.echo('Reload request received for member {0} and will be processed within {1} seconds'.format(
member.name, config.get('loop_wait') or dcs.loop_wait)
@@ -1095,7 +1093,6 @@ def restart(obj: Dict[str, Any], cluster_name: str, group: Optional[int], member
content['postgres_version'] = version
if scheduled_at:
from patroni.config import get_global_config
if get_global_config(cluster).is_paused:
raise PatroniCtlException("Can't schedule restart in the paused state")
content['schedule'] = scheduled_at.isoformat()
@@ -1223,19 +1220,22 @@ def _do_failover_or_switchover(obj: Dict[str, Any], action: str, cluster_name: s
dcs = get_dcs(obj, cluster_name, group)
cluster = dcs.get_cluster()
if action == 'switchover' and (cluster.leader is None or not cluster.leader.name):
raise PatroniCtlException('This cluster has no leader')
global_config = get_global_config(cluster)
if leader is None:
if force or action == 'failover':
leader = cluster.leader and cluster.leader.name
else:
from patroni.config import get_global_config
prompt = 'Standby Leader' if get_global_config(cluster).is_standby_cluster else 'Primary'
leader = click.prompt(prompt, type=str, default=(cluster.leader and cluster.leader.member.name))
# leader has to be be defined for switchover only
if action == 'switchover':
if cluster.leader is None or not cluster.leader.name:
raise PatroniCtlException('This cluster has no leader')
if leader is not None and cluster.leader and cluster.leader.member.name != leader:
raise PatroniCtlException('Member {0} is not the leader of cluster {1}'.format(leader, cluster_name))
if leader is None:
if force:
leader = cluster.leader.name
else:
prompt = 'Standby Leader' if global_config.is_standby_cluster else 'Primary'
leader = click.prompt(prompt, type=str, default=(cluster.leader and cluster.leader.name))
if cluster.leader.name != leader:
raise PatroniCtlException(f'Member {leader} is not the leader of cluster {cluster_name}')
# excluding members with nofailover tag
candidate_names = [str(m.name) for m in cluster.members if m.name != leader and not m.nofailover]
@@ -1255,7 +1255,16 @@ def _do_failover_or_switchover(obj: Dict[str, Any], action: str, cluster_name: s
raise PatroniCtlException(action.title() + ' target and source are the same.')
if candidate and candidate not in candidate_names:
raise PatroniCtlException('Member {0} does not exist in cluster {1}'.format(candidate, cluster_name))
raise PatroniCtlException(
f'Member {candidate} does not exist in cluster {cluster_name} or is tagged as nofailover')
if all((not force,
action == 'failover',
global_config.is_synchronous_mode,
not cluster.sync.is_empty,
not cluster.sync.matches(candidate, True))):
if click.confirm(f'Are you sure you want to failover to the asynchronous node {candidate}'):
raise PatroniCtlException('Aborting ' + action)
scheduled_at_str = None
scheduled_at = None
@@ -1268,25 +1277,29 @@ def _do_failover_or_switchover(obj: Dict[str, Any], action: str, cluster_name: s
scheduled_at = parse_scheduled(scheduled)
if scheduled_at:
from patroni.config import get_global_config
if get_global_config(cluster).is_paused:
if global_config.is_paused:
raise PatroniCtlException("Can't schedule switchover in the paused state")
scheduled_at_str = scheduled_at.isoformat()
failover_value = {'leader': leader, 'candidate': candidate, 'scheduled_at': scheduled_at_str}
failover_value = {'candidate': candidate}
if action == 'switchover':
failover_value['leader'] = leader
if scheduled_at_str:
failover_value['scheduled_at'] = scheduled_at_str
logging.debug(failover_value)
# By now we have established that the leader exists and the candidate exists
if not force:
demote_msg = ', demoting current leader ' + leader if leader else ''
demote_msg = f', demoting current leader {cluster.leader.name}' if cluster.leader else ''
if scheduled_at_str:
if not click.confirm('Are you sure you want to schedule {0} of cluster {1} at {2}{3}?'
.format(action, cluster_name, scheduled_at_str, demote_msg)):
# only switchover can be scheduled
if not click.confirm(f'Are you sure you want to schedule switchover of cluster '
f'{cluster_name} at {scheduled_at_str}{demote_msg}?'):
# action as a var to catch a regression in the tests
raise PatroniCtlException('Aborting scheduled ' + action)
else:
if not click.confirm('Are you sure you want to {0} cluster {1}{2}?'
.format(action, cluster_name, demote_msg)):
if not click.confirm(f'Are you sure you want to {action} cluster {cluster_name}{demote_msg}?'):
raise PatroniCtlException('Aborting ' + action)
r = None
@@ -1332,6 +1345,8 @@ def failover(obj: Dict[str, Any], cluster_name: str, group: Optional[int],
.. note::
If *leader* is given perform a switchover instead of a failover.
This behavior is deprecated. ``--leader`` option support will be
removed in the next major release.
.. seealso::
Refer to :func:`_do_failover_or_switchover` for details.
@@ -1345,7 +1360,12 @@ def failover(obj: Dict[str, Any], cluster_name: str, group: Optional[int],
:param candidate: name of a standby member to be promoted. Nodes that are tagged with ``nofailover`` cannot be used.
:param force: perform the failover or switchover without asking for confirmations.
"""
action = 'switchover' if leader else 'failover'
action = 'failover'
if leader:
action = 'switchover'
click.echo(click.style(
'Supplying a leader name using this command is deprecated and will be removed in a future version of'
' Patroni, change your scripts to use `switchover` instead.\nExecuting switchover!', fg='red'))
_do_failover_or_switchover(obj, action, cluster_name, group, leader, candidate, force)
@@ -1718,7 +1738,6 @@ def wait_until_pause_is_applied(dcs: AbstractDCS, paused: bool, old_cluster: Clu
:param old_cluster: original cluster information before pause or unpause has been requested. Used to report which
nodes are still pending to have ``pause`` equal *paused* at a given point in time.
"""
from patroni.config import get_global_config
config = get_global_config(old_cluster)
click.echo("'{0}' request sent, waiting until it is recognized by all nodes".format(paused and 'pause' or 'resume'))
@@ -1756,7 +1775,6 @@ def toggle_pause(config: Dict[str, Any], cluster_name: str, group: Optional[int]
* ``pause`` state is already *paused*; or
* cluster contains no accessible members.
"""
from patroni.config import get_global_config
dcs = get_dcs(config, cluster_name, group)
cluster = dcs.get_cluster()
if get_global_config(cluster).is_paused == paused:
patroni/ha.py
+47 -23
View File
@@ -225,6 +225,17 @@ class Ha(object):
"""
return self.is_synchronous_mode() and not self.cluster.sync.is_empty
def _get_failover_action_name(self) -> str:
"""Return the currently requested manual failover action name or the default ``failover``.
:returns: :class:`str` representing the manually requested action (``manual failover`` if no leader
is specified in the ``/failover`` in DCS, ``switchover`` otherwise) or ``failover`` if
``/failover`` is empty.
"""
if not self.cluster.failover:
return 'failover'
return 'switchover' if self.cluster.failover.leader else 'manual failover'
def load_cluster_from_dcs(self) -> None:
cluster = self.dcs.get_cluster()
@@ -956,11 +967,12 @@ class Ha(object):
"""
candidates = self.get_failover_candidates(exclude_failover_candidate)
action = self._get_failover_action_name()
if self.is_synchronous_mode() and self.cluster.failover and self.cluster.failover.candidate and not candidates:
logger.warning('Failover candidate=%s does not match with sync_standbys=%s',
self.cluster.failover.candidate, self.cluster.sync.sync_standby)
logger.warning('%s candidate=%s does not match with sync_standbys=%s',
action.title(), self.cluster.failover.candidate, self.cluster.sync.sync_standby)
elif not candidates:
logger.warning('manual failover: candidates list is empty')
logger.warning('%s: candidates list is empty', action)
ret = False
cluster_timeline = self.cluster.timeline
@@ -987,15 +999,18 @@ class Ha(object):
failover = self.cluster.failover
if TYPE_CHECKING: # pragma: no cover
assert failover is not None
if failover.candidate: # manual failover to specific member
if failover.candidate == self.state_handler.name: # manual failover to me
action = self._get_failover_action_name()
if failover.candidate: # manual failover/switchover to specific member
if failover.candidate == self.state_handler.name: # manual failover/switchover to me
return True
elif self.is_paused():
# Remove failover key if the node to failover has terminated to avoid waiting for it indefinitely
# In order to avoid attempts to delete this key from all nodes only the primary is allowed to do it.
if not self.cluster.get_member(failover.candidate, fallback_to_leader=False)\
and self.state_handler.is_primary():
logger.warning("manual failover: removing failover key because failover candidate is not running")
logger.warning("%s: removing failover key because failover candidate is not running", action)
self.dcs.manual_failover('', '', version=failover.version)
return None
return False
@@ -1011,17 +1026,17 @@ class Ha(object):
st = self.fetch_node_status(member)
not_allowed_reason = st.failover_limitation()
if not_allowed_reason is None: # node is healthy
logger.info('manual failover: to %s, i am %s', st.member.name, self.state_handler.name)
logger.info('%s: to %s, i am %s', action, st.member.name, self.state_handler.name)
return False
# we wanted to failover to specific member but it is not healthy
logger.warning('manual failover: member %s is %s', st.member.name, not_allowed_reason)
# we wanted to failover/switchover to specific member but it is not healthy
logger.warning('%s: member %s is %s', action, st.member.name, not_allowed_reason)
# at this point we should consider all members as a candidates for failover
# at this point we should consider all members as a candidates for failover/switchover
# i.e. we assume that failover.candidate is None
elif self.is_paused():
return False
# try to pick some other members to failover and check that they are healthy
# try to pick some other members for switchover and check that they are healthy
if failover.leader:
if self.state_handler.name == failover.leader: # I was the leader
# exclude desired member which is unhealthy if it was specified
@@ -1079,8 +1094,8 @@ class Ha(object):
if self.cluster.failover:
# When doing a switchover in synchronous mode only synchronous nodes and former leader are allowed to race
if self.sync_mode_is_active() and not self.cluster.sync.matches(self.state_handler.name, True) and \
self.cluster.failover.leader:
if self.cluster.failover.leader and self.sync_mode_is_active() \
and not self.cluster.sync.matches(self.state_handler.name, True):
return False
return self.manual_failover_process_no_leader() or False
@@ -1244,28 +1259,35 @@ class Ha(object):
:returns: action message if demote was initiated, None if no action was taken"""
failover = self.cluster.failover
# if there is no failover key or
# I am holding the lock but am not primary = I am the standby leader,
# then do nothing
if not failover or (self.is_paused() and not self.state_handler.is_primary()):
return
action = self._get_failover_action_name()
bare_action = action.replace('manual ', '')
# it is not the time for the scheduled switchover yet, do nothing
if (failover.scheduled_at and not
self.should_run_scheduled_action("failover", failover.scheduled_at, lambda:
self.should_run_scheduled_action(bare_action, failover.scheduled_at, lambda:
self.dcs.manual_failover('', '', version=failover.version))):
return
if not failover.leader or failover.leader == self.state_handler.name:
if not failover.candidate or failover.candidate != self.state_handler.name:
if not failover.candidate and self.is_paused():
logger.warning('Failover is possible only to a specific candidate in a paused state')
logger.warning('%s is possible only to a specific candidate in a paused state', action.title())
elif self.is_failover_possible():
ret = self._async_executor.try_run_async('manual failover: demote', self.demote, ('graceful',))
return ret or 'manual failover: demoting myself'
ret = self._async_executor.try_run_async(f'{action}: demote', self.demote, ('graceful',))
return ret or f'{action}: demoting myself'
else:
logger.warning('manual failover: no healthy members found, failover is not possible')
logger.warning('%s: no healthy members found, %s is not possible',
action, bare_action)
else:
logger.warning('manual failover: I am already the leader, no need to failover')
logger.warning('%s: I am already the leader, no need to %s', action, bare_action)
else:
logger.warning('manual failover: leader name does not match: %s != %s',
failover.leader, self.state_handler.name)
logger.warning('%s: leader name does not match: %s != %s', action, failover.leader, self.state_handler.name)
logger.info('Cleaning up failover key')
self.dcs.manual_failover('', '', version=failover.version)
@@ -1322,6 +1344,7 @@ class Ha(object):
self._delete_leader()
return 'removed leader lock because postgres is not running as primary'
# update lock to avoid split-brain
if self.update_lock(True):
msg = self.process_manual_failover_from_leader()
if msg is not None:
@@ -1990,8 +2013,9 @@ class Ha(object):
exclude = [self.state_handler.name] + ([failover.candidate] if failover and exclude_failover_candidate else [])
def is_eligible(node: Member) -> bool:
# TODO: allow manual failover (=no leader specified) to async node
if self.sync_mode_is_active() and not self.cluster.sync.matches(node.name):
# in synchronous mode we allow failover (not switchover!) to async node
if self.sync_mode_is_active() and not self.cluster.sync.matches(node.name)\
and not (failover and not failover.leader):
return False
# Don't spend time on "nofailover" nodes checking.
# We also don't need nodes which we can't query with the api in the list.
tests/test_api.py
+120 -45
View File
@@ -516,86 +516,161 @@ class TestRestApiHandler(unittest.TestCase):
post = 'POST /switchover HTTP/1.0' + self._authorization + '\nContent-Length: '
MockRestApiServer(RestApiHandler, post + '7\n\n{"1":2}')
# Invalid content
with patch.object(RestApiHandler, 'write_response') as response_mock:
MockRestApiServer(RestApiHandler, post + '7\n\n{"1":2}')
response_mock.assert_called_with(400, 'Switchover could be performed only from a specific leader')
# Empty content
request = post + '0\n\n'
MockRestApiServer(RestApiHandler, request)
cluster.leader.name = 'postgresql1'
MockRestApiServer(RestApiHandler, request)
# [Switchover without a candidate]
request = post + '25\n\n{"leader": "postgresql1"}'
with patch.object(GlobalConfig, 'is_paused', PropertyMock(return_value=True)):
# Cluster with only a leader
with patch.object(RestApiHandler, 'write_response') as response_mock:
cluster.leader.name = 'postgresql1'
request = post + '25\n\n{"leader": "postgresql1"}'
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(
412, 'switchover is not possible: cluster does not have members except leader')
for is_synchronous_mode in (True, False):
with patch.object(GlobalConfig, 'is_synchronous_mode', PropertyMock(return_value=is_synchronous_mode)):
# Switchover in pause mode
with patch.object(RestApiHandler, 'write_response') as response_mock, \
patch.object(GlobalConfig, 'is_paused', PropertyMock(return_value=True)):
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(
400, 'Switchover is possible only to a specific candidate in a paused state')
# No healthy nodes to promote in both sync and async mode
for is_synchronous_mode, response in (
(True, 'switchover is not possible: can not find sync_standby'),
(False, 'switchover is not possible: cluster does not have members except leader')):
with patch.object(GlobalConfig, 'is_synchronous_mode', PropertyMock(return_value=is_synchronous_mode)), \
patch.object(RestApiHandler, 'write_response') as response_mock:
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(412, response)
cluster.leader.name = 'postgresql2'
request = post + '53\n\n{"leader": "postgresql1", "candidate": "postgresql2"}'
MockRestApiServer(RestApiHandler, request)
# [Switchover to the candidate specified]
# Candidate to promote is the same as the leader specified
with patch.object(RestApiHandler, 'write_response') as response_mock:
request = post + '53\n\n{"leader": "postgresql2", "candidate": "postgresql2"}'
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(400, 'Switchover target and source are the same')
# Current leader is different from the one specified
with patch.object(RestApiHandler, 'write_response') as response_mock:
cluster.leader.name = 'postgresql2'
request = post + '53\n\n{"leader": "postgresql1", "candidate": "postgresql2"}'
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(412, 'leader name does not match')
# Candidate to promote is not a member of the cluster
cluster.leader.name = 'postgresql1'
cluster.sync.matches.return_value = False
for is_synchronous_mode in (True, False):
with patch.object(GlobalConfig, 'is_synchronous_mode', PropertyMock(return_value=is_synchronous_mode)):
for is_synchronous_mode, response in (
(True, 'candidate name does not match with sync_standby'), (False, 'candidate does not exists')):
with patch.object(GlobalConfig, 'is_synchronous_mode', PropertyMock(return_value=is_synchronous_mode)), \
patch.object(RestApiHandler, 'write_response') as response_mock:
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(412, response)
cluster.members = [Member(0, 'postgresql0', 30, {'api_url': 'http'}),
Member(0, 'postgresql2', 30, {'api_url': 'http'})]
MockRestApiServer(RestApiHandler, request)
cluster.failover = None
MockRestApiServer(RestApiHandler, request)
# Failover key is empty in DCS
with patch.object(RestApiHandler, 'write_response') as response_mock:
cluster.failover = None
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(503, 'Switchover failed')
dcs.get_cluster.side_effect = [cluster]
MockRestApiServer(RestApiHandler, request)
# Result polling failed
with patch.object(RestApiHandler, 'write_response') as response_mock:
dcs.get_cluster.side_effect = [cluster]
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(503, 'Switchover status unknown')
cluster2 = cluster.copy()
cluster2.leader.name = 'postgresql0'
cluster2.is_unlocked.return_value = False
dcs.get_cluster.side_effect = [cluster, cluster2]
MockRestApiServer(RestApiHandler, request)
# Switchover to a node different from the candidate specified
with patch.object(RestApiHandler, 'write_response') as response_mock:
cluster2 = cluster.copy()
cluster2.leader.name = 'postgresql0'
cluster2.is_unlocked.return_value = False
dcs.get_cluster.side_effect = [cluster, cluster2]
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(200, 'Switched over to "postgresql0" instead of "postgresql2"')
cluster2.leader.name = 'postgresql2'
dcs.get_cluster.side_effect = [cluster, cluster2]
MockRestApiServer(RestApiHandler, request)
# Successful switchover to the candidate
with patch.object(RestApiHandler, 'write_response') as response_mock:
cluster2.leader.name = 'postgresql2'
dcs.get_cluster.side_effect = [cluster, cluster2]
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(200, 'Successfully switched over to "postgresql2"')
with patch.object(RestApiHandler, 'write_response') as response_mock:
dcs.manual_failover.return_value = False
dcs.get_cluster.side_effect = None
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(503, 'failed to write failover key into DCS')
dcs.get_cluster.side_effect = None
dcs.manual_failover.return_value = False
MockRestApiServer(RestApiHandler, request)
dcs.manual_failover.return_value = True
with patch.object(MockHa, 'fetch_nodes_statuses', Mock(return_value=[])):
# Candidate is not healthy to be promoted
with patch.object(MockHa, 'fetch_nodes_statuses', Mock(return_value=[])), \
patch.object(RestApiHandler, 'write_response') as response_mock:
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(412, 'switchover is not possible: no good candidates have been found')
# [Scheduled switchover]
# Valid future date
request = post + '103\n\n{"leader": "postgresql1", "member": "postgresql2",' +\
' "scheduled_at": "6016-02-15T18:13:30.568224+01:00"}'
MockRestApiServer(RestApiHandler, request)
with patch.object(GlobalConfig, 'is_paused', PropertyMock(return_value=True)), \
patch.object(MockPatroni, 'dcs') as d:
d.manual_failover.return_value = False
with patch.object(RestApiHandler, 'write_response') as response_mock:
request = post + '103\n\n{"leader": "postgresql1", "member": "postgresql2",' + \
' "scheduled_at": "6016-02-15T18:13:30.568224+01:00"}'
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(202, 'Switchover scheduled')
# Exception: No timezone specified
request = post + '97\n\n{"leader": "postgresql1", "member": "postgresql2",' +\
' "scheduled_at": "6016-02-15T18:13:30.568224"}'
MockRestApiServer(RestApiHandler, request)
# Schedule in paused mode
with patch.object(RestApiHandler, 'write_response') as response_mock, \
patch.object(GlobalConfig, 'is_paused', PropertyMock(return_value=True)):
dcs.manual_failover.return_value = False
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(400, "Can't schedule switchover in the paused state")
# No timezone specified
with patch.object(RestApiHandler, 'write_response') as response_mock:
request = post + '97\n\n{"leader": "postgresql1", "member": "postgresql2",' + \
' "scheduled_at": "6016-02-15T18:13:30.568224"}'
MockRestApiServer(RestApiHandler, request)
response_mock.assert_called_with(400, 'Timezone information is mandatory for the scheduled switchover')
# Exception: Scheduled in the past
request = post + '103\n\n{"leader": "postgresql1", "member": "postgresql2", "scheduled_at": "'
MockRestApiServer(RestApiHandler, request + '1016-02-15T18:13:30.568224+01:00"}')
# Scheduled in the past
with patch.object(RestApiHandler, 'write_response') as response_mock:
MockRestApiServer(RestApiHandler, request + '1016-02-15T18:13:30.568224+01:00"}')
response_mock.assert_called_with(422, 'Cannot schedule switchover in the past')
# Invalid date
self.assertIsNotNone(MockRestApiServer(RestApiHandler, request + '2010-02-29T18:13:30.568224+01:00"}'))
with patch.object(RestApiHandler, 'write_response') as response_mock:
MockRestApiServer(RestApiHandler, request + '2010-02-29T18:13:30.568224+01:00"}')
response_mock.assert_called_with(
422, 'Unable to parse scheduled timestamp. It should be in an unambiguous format, e.g. ISO 8601')
def test_do_POST_failover(self):
post = 'POST /failover HTTP/1.0' + self._authorization + '\nContent-Length: '
MockRestApiServer(RestApiHandler, post + '14\n\n{"leader":"1"}')
MockRestApiServer(RestApiHandler, post + '37\n\n{"candidate":"2","scheduled_at": "1"}')
with patch.object(RestApiHandler, 'write_response') as response_mock:
MockRestApiServer(RestApiHandler, post + '14\n\n{"leader":"1"}')
response_mock.assert_called_once_with(400, 'Failover could be performed only to a specific candidate')
with patch.object(RestApiHandler, 'write_response') as response_mock:
MockRestApiServer(RestApiHandler, post + '37\n\n{"candidate":"2","scheduled_at": "1"}')
response_mock.assert_called_once_with(400, "Failover can't be scheduled")
with patch.object(RestApiHandler, 'write_response') as response_mock:
MockRestApiServer(RestApiHandler, post + '30\n\n{"leader":"1","candidate":"2"}')
response_mock.assert_called_once_with(412, 'leader name does not match')
@patch.object(MockHa, 'is_leader', Mock(return_value=True))
def test_do_POST_citus(self):
tests/test_ctl.py
+92 -45
View File
@@ -21,10 +21,17 @@ from .test_ha import get_cluster_initialized_without_leader, get_cluster_initial
get_cluster_initialized_with_only_leader, get_cluster_not_initialized_without_leader, get_cluster, Member
@patch('patroni.ctl.load_config', Mock(return_value={
'scope': 'alpha', 'restapi': {'listen': '::', 'certfile': 'a'}, 'ctl': {'certfile': 'a'},
'etcd': {'host': 'localhost:2379'}, 'citus': {'database': 'citus', 'group': 0},
'postgresql': {'data_dir': '.', 'pgpass': './pgpass', 'parameters': {}, 'retry_timeout': 5}}))
DEFAULT_CONFIG = {
'scope': 'alpha',
'restapi': {'listen': '::', 'certfile': 'a'},
'ctl': {'certfile': 'a'},
'etcd': {'host': 'localhost:2379'},
'citus': {'database': 'citus', 'group': 0},
'postgresql': {'data_dir': '.', 'pgpass': './pgpass', 'parameters': {}, 'retry_timeout': 5}
}
@patch('patroni.ctl.load_config', Mock(return_value=DEFAULT_CONFIG))
class TestCtl(unittest.TestCase):
TEST_ROLES = ('master', 'primary', 'leader')
@@ -96,91 +103,131 @@ class TestCtl(unittest.TestCase):
mock_get_dcs.return_value = self.e
mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
mock_get_dcs.return_value.set_failover_value = Mock()
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='leader\nother\n\ny')
assert 'leader' in result.output
# Confirm
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='leader\nother\n\ny')
self.assertEqual(result.exit_code, 0)
# Abort
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='leader\nother\n\nN')
self.assertEqual(result.exit_code, 1)
# Without a candidate with --force option
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0', '--force'])
self.assertEqual(result.exit_code, 0)
# Scheduled (confirm)
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'],
input='leader\nother\n2300-01-01T12:23:00\ny')
assert result.exit_code == 0
self.assertEqual(result.exit_code, 0)
# Scheduled (abort)
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0',
'--scheduled', '2015-01-01T12:00:00+01:00'], input='leader\nother\n\nN')
self.assertEqual(result.exit_code, 1)
# Scheduled with --force option
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0',
'--force', '--scheduled', '2015-01-01T12:00:00+01:00'])
self.assertEqual(result.exit_code, 0)
# Scheduled in pause mode
with patch('patroni.config.GlobalConfig.is_paused', PropertyMock(return_value=True)):
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0',
'--force', '--scheduled', '2015-01-01T12:00:00'])
assert result.exit_code == 1
# Aborting switchover, as we answer NO to the confirmation
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='leader\nother\n\nN')
assert result.exit_code == 1
# Aborting scheduled switchover, as we answer NO to the confirmation
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0',
'--scheduled', '2015-01-01T12:00:00+01:00'], input='leader\nother\n\nN')
assert result.exit_code == 1
self.assertEqual(result.exit_code, 1)
self.assertIn("Can't schedule switchover in the paused state", result.output)
# Target and source are equal
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='leader\nleader\n\ny')
assert result.exit_code == 1
self.assertEqual(result.exit_code, 1)
self.assertIn('Switchover target and source are the same', result.output)
# Reality is not part of this cluster
# Candidate is not a member of the cluster
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='leader\nReality\n\ny')
assert result.exit_code == 1
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0', '--force'])
assert 'Member' in result.output
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0',
'--force', '--scheduled', '2015-01-01T12:00:00+01:00'])
assert result.exit_code == 0
self.assertEqual(result.exit_code, 1)
self.assertIn('Member Reality does not exist in cluster dummy or is tagged as nofailover', result.output)
# Invalid timestamp
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0', '--force', '--scheduled', 'invalid'])
assert result.exit_code != 0
self.assertEqual(result.exit_code, 1)
self.assertIn('Unable to parse scheduled timestamp', result.output)
# Invalid timestamp
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0',
'--force', '--scheduled', '2115-02-30T12:00:00+01:00'])
assert result.exit_code != 0
self.assertEqual(result.exit_code, 1)
self.assertIn('Unable to parse scheduled timestamp', result.output)
# Specifying wrong leader
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='dummy')
assert result.exit_code == 1
self.assertEqual(result.exit_code, 1)
self.assertIn('Member dummy is not the leader of cluster dummy', result.output)
# Errors while sending Patroni REST API request
with patch.object(PoolManager, 'request', Mock(side_effect=Exception)):
# Non-responding patroni
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'],
input='leader\nother\n2300-01-01T12:23:00\ny')
assert 'falling back to DCS' in result.output
self.assertIn('falling back to DCS', result.output)
with patch.object(PoolManager, 'request') as mocked:
mocked.return_value.status = 500
with patch.object(PoolManager, 'request') as mock_api_request:
mock_api_request.return_value.status = 500
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='leader\nother\n\ny')
assert 'Switchover failed' in result.output
self.assertIn('Switchover failed', result.output)
mocked.return_value.status = 501
mocked.return_value.data = b'Server does not support this operation'
mock_api_request.return_value.status = 501
mock_api_request.return_value.data = b'Server does not support this operation'
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='leader\nother\n\ny')
assert 'Switchover failed' in result.output
self.assertIn('Switchover failed', result.output)
# No members available
mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_only_leader
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='leader\nother\n\ny')
assert result.exit_code == 1
self.assertEqual(result.exit_code, 1)
self.assertIn('No candidates found to switchover to', result.output)
# No leader available
mock_get_dcs.return_value.get_cluster = get_cluster_initialized_without_leader
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--group', '0'], input='leader\nother\n\ny')
assert result.exit_code == 1
self.assertEqual(result.exit_code, 1)
self.assertIn('This cluster has no leader', result.output)
# Citus cluster, no group number specified
result = self.runner.invoke(ctl, ['switchover', 'dummy', '--force'], input='\n')
self.assertEqual(result.exit_code, 1)
self.assertIn('For Citus clusters the --group must me specified', result.output)
@patch('patroni.ctl.get_dcs')
@patch.object(PoolManager, 'request', Mock(return_value=MockResponse()))
@patch('patroni.ctl.request_patroni', Mock(return_value=MockResponse()))
def test_failover(self, mock_get_dcs):
mock_get_dcs.return_value = self.e
mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
mock_get_dcs.return_value.set_failover_value = Mock()
result = self.runner.invoke(ctl, ['failover', 'dummy', '--force'], input='\n')
assert 'For Citus clusters the --group must me specified' in result.output
# No candidate specified
mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
result = self.runner.invoke(ctl, ['failover', 'dummy'], input='0\n')
assert 'Failover could be performed only to a specific candidate' in result.output
self.assertIn('Failover could be performed only to a specific candidate', result.output)
cluster = get_cluster_initialized_with_leader(sync=('leader', 'other'))
# Temp test to check a fallback to switchover if leader is specified
with patch('patroni.ctl._do_failover_or_switchover') as failover_func_mock:
result = self.runner.invoke(ctl, ['failover', '--leader', 'leader', 'dummy'], input='0\n')
self.assertIn('Supplying a leader name using this command is deprecated', result.output)
failover_func_mock.assert_called_once_with(
DEFAULT_CONFIG, 'switchover', 'dummy', None, 'leader', None, False)
# Failover to an async member in sync mode (confirm)
cluster.members.append(Member(0, 'async', 28, {'api_url': 'http://127.0.0.1:8012/patroni'}))
cluster.config.data['synchronous_mode'] = True
mock_get_dcs.return_value.get_cluster = Mock(return_value=cluster)
result = self.runner.invoke(ctl, ['failover', 'dummy', '--group', '0', '--candidate', 'async'], input='y\ny')
self.assertIn('Are you sure you want to failover to the asynchronous node async', result.output)
# Failover to an async member in sync mode (abort)
mock_get_dcs.return_value.get_cluster = Mock(return_value=cluster)
result = self.runner.invoke(ctl, ['failover', 'dummy', '--group', '0', '--candidate', 'async'], input='N')
self.assertEqual(result.exit_code, 1)
@patch('patroni.dcs.dcs_modules', Mock(return_value=['patroni.dcs.dummy', 'patroni.dcs.etcd']))
def test_get_dcs(self):
tests/test_ha.py
+265 -98
View File
@@ -435,6 +435,7 @@ class TestHa(PostgresInit):
def test_promote_without_watchdog(self):
self.ha.has_lock = true
self.p.is_primary = true
with patch.object(Watchdog, 'activate', Mock(return_value=False)):
self.assertEqual(self.ha.run_cycle(), 'Demoting self because watchdog could not be activated')
self.p.is_primary = false
@@ -614,6 +615,7 @@ class TestHa(PostgresInit):
self.ha.cluster = get_cluster_not_initialized_without_leader()
self.e.initialize = true
self.ha.bootstrap()
self.p.is_primary = true
with patch.object(Watchdog, 'activate', Mock(return_value=False)), \
patch('patroni.ha.logger.error') as mock_logger:
self.assertEqual(self.ha.post_bootstrap(), 'running post_bootstrap')
@@ -687,110 +689,289 @@ class TestHa(PostgresInit):
@patch('patroni.postgresql.citus.CitusHandler.is_coordinator', Mock(return_value=False))
def test_manual_failover_from_leader(self):
self.ha.has_lock = true # I am the leader
# to me
with patch('patroni.ha.logger.warning') as mock_warning:
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', self.p.name, None))
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
mock_warning.assert_called_with('%s: I am already the leader, no need to %s', 'manual failover', 'failover')
# to a non-existent candidate
with patch('patroni.ha.logger.warning') as mock_warning:
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', 'blabla', None))
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
mock_warning.assert_called_with(
'%s: no healthy members found, %s is not possible', 'manual failover', 'failover')
# to an existent candidate
self.ha.fetch_node_status = get_node_status()
self.ha.has_lock = true
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', '', None))
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', self.p.name, None))
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', 'blabla', None))
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
f = Failover(0, self.p.name, '', None)
self.ha.cluster = get_cluster_initialized_with_leader(f)
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', 'b', None))
self.ha.cluster.members.append(Member(0, 'b', 28, {'api_url': 'http://127.0.0.1:8011/patroni'}))
self.assertEqual(self.ha.run_cycle(), 'manual failover: demoting myself')
# to a candidate on an older timeline
with patch('patroni.ha.logger.info') as mock_info:
self.ha.fetch_node_status = get_node_status(timeline=1)
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.assertEqual(mock_info.call_args_list[0][0],
('Timeline %s of member %s is behind the cluster timeline %s', 1, 'b', 2))
# to a lagging candidate
with patch('patroni.ha.logger.info') as mock_info:
self.ha.fetch_node_status = get_node_status(wal_position=1)
self.ha.cluster.config.data.update({'maximum_lag_on_failover': 5})
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.assertEqual(mock_info.call_args_list[0][0],
('Member %s exceeds maximum replication lag', 'b'))
self.ha.cluster.members.pop()
@patch('patroni.postgresql.citus.CitusHandler.is_coordinator', Mock(return_value=False))
def test_manual_switchover_from_leader(self):
self.ha.has_lock = true # I am the leader
self.ha.fetch_node_status = get_node_status()
# different leader specified in failover key, no candidate
with patch('patroni.ha.logger.warning') as mock_warning:
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', '', None))
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
mock_warning.assert_called_with(
'%s: leader name does not match: %s != %s', 'switchover', 'blabla', 'postgresql0')
# no candidate
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, '', None))
self.assertEqual(self.ha.run_cycle(), 'switchover: demoting myself')
self.ha._rewind.rewind_or_reinitialize_needed_and_possible = true
self.assertEqual(self.ha.run_cycle(), 'manual failover: demoting myself')
self.ha.fetch_node_status = get_node_status(nofailover=True)
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.ha.fetch_node_status = get_node_status(watchdog_failed=True)
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.ha.fetch_node_status = get_node_status(timeline=1)
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.ha.fetch_node_status = get_node_status(wal_position=1)
self.ha.cluster.config.data.update({'maximum_lag_on_failover': 5})
self.ha.global_config = self.ha.patroni.config.get_global_config(self.ha.cluster)
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), 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.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.assertEqual(self.ha.run_cycle(), 'switchover: demoting myself')
# 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()
# other members with failover_limitation_s
with patch('patroni.ha.logger.info') as mock_info:
self.ha.fetch_node_status = get_node_status(nofailover=True)
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.assertEqual(mock_info.call_args_list[0][0], ('Member %s is %s', 'leader', 'not allowed to promote'))
with patch('patroni.ha.logger.info') as mock_info:
self.ha.fetch_node_status = get_node_status(watchdog_failed=True)
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.assertEqual(mock_info.call_args_list[0][0], ('Member %s is %s', 'leader', 'not watchdog capable'))
with patch('patroni.ha.logger.info') as mock_info:
self.ha.fetch_node_status = get_node_status(timeline=1)
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.assertEqual(mock_info.call_args_list[0][0],
('Timeline %s of member %s is behind the cluster timeline %s', 1, 'leader', 2))
with patch('patroni.ha.logger.info') as mock_info:
self.ha.fetch_node_status = get_node_status(wal_position=1)
self.ha.cluster.config.data.update({'maximum_lag_on_failover': 5})
self.ha.global_config = self.ha.patroni.config.get_global_config(self.ha.cluster)
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.assertEqual(mock_info.call_args_list[0][0], ('Member %s exceeds maximum replication lag', 'leader'))
@patch('patroni.postgresql.citus.CitusHandler.is_coordinator', Mock(return_value=False))
def test_scheduled_switchover_from_leader(self):
self.ha.has_lock = true # I am the leader
self.ha.fetch_node_status = get_node_status()
# switchover scheduled time must include timezone
with patch('patroni.ha.logger.warning') as mock_warning:
scheduled = datetime.datetime.now()
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, 'blabla', scheduled))
self.assertEqual(self.ha.run_cycle(), 'no action. I am (postgresql0), the leader with the lock')
self.assertIn('Incorrect value of scheduled_at: %s', mock_warning.call_args_list[0][0])
# scheduled now
scheduled = datetime.datetime.utcnow().replace(tzinfo=tzutc)
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
self.assertEqual('no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, 'b', scheduled))
self.ha.cluster.members.append(Member(0, 'b', 28, {'api_url': 'http://127.0.0.1:8011/patroni'}))
self.assertEqual('switchover: demoting myself', 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.assertEqual('no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
# scheduled in the future
with patch('patroni.ha.logger.info') as mock_info:
scheduled = scheduled + datetime.timedelta(seconds=30)
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, 'blabla', scheduled))
self.assertEqual('no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
self.assertIn('Awaiting %s at %s (in %.0f seconds)', mock_info.call_args_list[0][0])
scheduled = scheduled + datetime.timedelta(seconds=-600)
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
self.assertEqual('no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
# stale value
with patch('patroni.ha.logger.warning') as mock_warning:
scheduled = scheduled + datetime.timedelta(seconds=-600)
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, 'b', scheduled))
self.ha.cluster.members.append(Member(0, 'b', 28, {'api_url': 'http://127.0.0.1:8011/patroni'}))
self.assertEqual('no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
self.assertIn('Found a stale %s value, cleaning up: %s', mock_warning.call_args_list[0][0])
scheduled = None
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
self.assertEqual('no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
def test_manual_switchover_from_leader_in_pause(self):
self.ha.has_lock = true # I am the leader
self.ha.is_paused = true
# no candidate
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, '', None))
with patch('patroni.ha.logger.warning') as mock_warning:
self.assertEqual('PAUSE: no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
mock_warning.assert_called_with(
'%s is possible only to a specific candidate in a paused state', 'Switchover')
def test_manual_failover_from_leader_in_pause(self):
self.ha.has_lock = true
self.ha.fetch_node_status = get_node_status()
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.assertEqual('PAUSE: no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, '', None))
self.assertEqual('PAUSE: no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
# failover from me, candidate is healthy
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, None, 'b', None))
self.ha.cluster.members.append(Member(0, 'b', 28, {'api_url': 'http://127.0.0.1:8011/patroni'}))
self.assertEqual('PAUSE: manual failover: demoting myself', self.ha.run_cycle())
self.ha.cluster.members.pop()
def test_manual_failover_from_leader_in_synchronous_mode(self):
self.ha.has_lock = true
self.ha.is_synchronous_mode = true
self.ha.process_sync_replication = Mock()
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, 'a', None), (self.p.name, None))
self.assertEqual('no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, 'a', None), (self.p.name, 'a'))
self.ha.is_failover_possible = true
self.ha.fetch_node_status = get_node_status()
# I am the leader
self.p.is_primary = true
self.ha.has_lock = true
# the candidate is not in sync members but we allow failover to an async candidate
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, None, 'b', None), sync=(self.p.name, 'a'))
self.ha.cluster.members.append(Member(0, 'b', 28, {'api_url': 'http://127.0.0.1:8011/patroni'}))
self.assertEqual('manual failover: demoting myself', self.ha.run_cycle())
self.ha.cluster.members.pop()
def test_manual_switchover_from_leader_in_synchronous_mode(self):
self.ha.is_synchronous_mode = true
self.ha.process_sync_replication = Mock()
# I am the leader
self.p.is_primary = true
self.ha.has_lock = true
# candidate specified is not in sync members
with patch('patroni.ha.logger.warning') as mock_warning:
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, 'a', None),
sync=(self.p.name, 'blabla'))
self.assertEqual('no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
self.assertEqual(mock_warning.call_args_list[0][0],
('%s candidate=%s does not match with sync_standbys=%s', 'Switchover', 'a', 'blabla'))
# the candidate is in sync members and is healthy
self.ha.fetch_node_status = get_node_status(wal_position=305419896)
self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, 'a', None),
sync=(self.p.name, 'a'))
self.ha.cluster.members.append(Member(0, 'a', 28, {'api_url': 'http://127.0.0.1:8011/patroni'}))
self.assertEqual('switchover: demoting myself', self.ha.run_cycle())
# the candidate is in sync members but is not healthy
with patch('patroni.ha.logger.info') as mock_info:
self.ha.fetch_node_status = get_node_status(nofailover=true)
self.assertEqual('no action. I am (postgresql0), the leader with the lock', self.ha.run_cycle())
self.assertEqual(mock_info.call_args_list[0][0], ('Member %s is %s', 'a', 'not allowed to promote'))
def test_manual_failover_process_no_leader(self):
self.p.is_primary = false
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', self.p.name, None))
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'leader', None))
self.p.set_role('replica')
self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
self.ha.fetch_node_status = get_node_status() # accessible, in_recovery
self.assertEqual(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.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
self.ha.fetch_node_status = get_node_status(reachable=False) # inaccessible, in_recovery
# failover to another member, fetch_node_status for candidate fails
with patch('patroni.ha.logger.warning') as mock_warning:
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'leader', None))
self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
self.assertEqual(mock_warning.call_args_list[1][0],
('%s: member %s is %s', 'manual failover', 'leader', 'not reachable'))
# failover to another member, candidate is accessible, in_recovery
self.p.set_role('replica')
self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
# set failover flag to True for all members of the cluster
self.ha.fetch_node_status = get_node_status()
self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
# set nofailover 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 = get_node_status(nofailover=True) # accessible, in_recovery
self.p.set_role('replica')
self.ha.fetch_node_status = get_node_status(nofailover=True)
self.assertEqual(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
# failover to me but I am set to nofailover. In no case I should be elected as a leader
self.p.set_role('replica')
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'postgresql0', None))
self.ha.patroni.nofailover = True
self.assertEqual(self.ha.run_cycle(), 'following a different leader because I am not allowed to promote')
self.ha.patroni.nofailover = False
# failover to another member that is on an older timeline (only failover_limitation() is checked)
with patch('patroni.ha.logger.info') as mock_info:
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'b', None))
self.ha.cluster.members.append(Member(0, 'b', 28, {'api_url': 'http://127.0.0.1:8011/patroni'}))
self.ha.fetch_node_status = get_node_status(timeline=1)
self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
mock_info.assert_called_with('%s: to %s, i am %s', 'manual failover', 'b', 'postgresql0')
# failover to another member lagging behind the cluster_lsn (only failover_limitation() is checked)
with patch('patroni.ha.logger.info') as mock_info:
self.ha.cluster.config.data.update({'maximum_lag_on_failover': 5})
self.ha.fetch_node_status = get_node_status(wal_position=1)
self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
mock_info.assert_called_with('%s: to %s, i am %s', 'manual failover', 'b', 'postgresql0')
def test_manual_switchover_process_no_leader(self):
self.p.is_primary = false
self.p.set_role('replica')
# I was the leader, other members are healthy
self.ha.fetch_node_status = get_node_status()
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, self.p.name, '', None))
self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
# I was the leader, I am the only healthy member
with patch('patroni.ha.logger.info') as mock_info:
self.ha.fetch_node_status = get_node_status(reachable=False) # inaccessible, in_recovery
self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
self.assertEqual(mock_info.call_args_list[0][0], ('Member %s is %s', 'leader', 'not reachable'))
self.assertEqual(mock_info.call_args_list[1][0], ('Member %s is %s', 'other', 'not reachable'))
def test_manual_failover_process_no_leader_in_synchronous_mode(self):
self.ha.is_synchronous_mode = true
self.p.is_primary = false
self.ha.fetch_node_status = get_node_status(nofailover=True) # other nodes are not healthy
# switchover to a specific node, which name doesn't match our name (postgresql0)
# manual failover when our name (postgresql0) isn't in the /sync key and the candidate node is not available
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'other', None),
sync=('leader1', 'blabla'))
self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
# manual failover when the candidate node isn't available but our name is in the /sync key
# while other sync node is nofailover
with patch('patroni.ha.logger.warning') as mock_warning:
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'other', None),
sync=('leader1', 'postgresql0'))
self.p.sync_handler.current_state = Mock(return_value=(CaseInsensitiveSet(), CaseInsensitiveSet()))
self.ha.dcs.write_sync_state = Mock(return_value=SyncState.empty())
self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
self.assertEqual(mock_warning.call_args_list[0][0],
('%s: member %s is %s', 'manual failover', 'other', 'not allowed to promote'))
# manual failover to our node (postgresql0),
# which name is not in sync nodes list (some sync nodes are available)
self.p.set_role('replica')
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'postgresql0', None),
sync=('leader1', 'other'))
self.p.sync_handler.current_state = Mock(return_value=(CaseInsensitiveSet(['leader1']),
CaseInsensitiveSet(['leader1'])))
self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
def test_manual_switchover_process_no_leader_in_synchronous_mode(self):
self.ha.is_synchronous_mode = true
self.p.is_primary = false
# to a specific node, which name doesn't match our name (postgresql0)
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', 'other', None))
self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
# switchover to our node (postgresql0), which name is not in sync nodes list
# to our node (postgresql0), which name is not in sync nodes list
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', 'postgresql0', None),
sync=('leader1', 'blabla'))
self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
# switchover from a specific leader, but our name (postgresql0) is not in the sync nodes list
# without candidate, our name (postgresql0) is not in the sync nodes list
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', '', None),
sync=('leader', 'blabla'))
self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
@@ -800,45 +981,31 @@ class TestHa(PostgresInit):
sync=('postgresql0'))
self.ha.patroni.nofailover = True
self.assertEqual(self.ha.run_cycle(), 'following a different leader because I am not allowed to promote')
self.ha.patroni.nofailover = False
# manual failover when our name (postgresql0) isn't in the /sync key and the `other` node is not available
self.ha.fetch_node_status = get_node_status(nofailover=True) # accessible, in_recovery
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'other', None),
sync=('leader1', 'blabla'))
self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
# manual failover when the `other` node isn't available but our name is in the /sync key
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'other', None),
sync=('leader1', 'postgresql0'))
self.p.sync_handler.current_state = Mock(return_value=(CaseInsensitiveSet(), CaseInsensitiveSet()))
self.ha.dcs.write_sync_state = Mock(return_value=SyncState.empty())
self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
# manual failover to our node (postgresql0),
# which name is not in sync nodes list (the leader and all sync nodes are not available)
self.p.set_role('replica')
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'postgresql0', None),
sync=('leader1', 'other'))
self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
# manual failover to our node (postgresql0),
# which name is not in sync nodes list (some sync nodes are available)
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'postgresql0', None),
sync=('leader1', 'other'))
self.p.set_role('replica')
self.p.sync_handler.current_state = Mock(return_value=(CaseInsensitiveSet(['leader1']),
CaseInsensitiveSet(['leader1'])))
self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
def test_manual_failover_process_no_leader_in_pause(self):
self.ha.is_paused = true
# I am running as primary, cluster is unlocked, the candidate is allowed to promote
# but we are in pause
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'other', None))
self.assertEqual(self.ha.run_cycle(), 'PAUSE: continue to run as primary without lock')
def test_manual_switchover_process_no_leader_in_pause(self):
self.ha.is_paused = true
# I am running as primary, cluster is unlocked, no candidate specified
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', '', None))
self.assertEqual(self.ha.run_cycle(), 'PAUSE: continue to run as primary without lock')
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', 'blabla', None))
self.assertEqual('PAUSE: acquired session lock as a leader', self.ha.run_cycle())
# the candidate is not running
with patch('patroni.ha.logger.warning') as mock_warning:
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', 'blabla', None))
self.assertEqual('PAUSE: acquired session lock as a leader', self.ha.run_cycle())
self.assertEqual(
mock_warning.call_args_list[0][0],
('%s: removing failover key because failover candidate is not running', 'switchover'))
# switchover to me, I am not leader
self.p.is_primary = false
self.p.set_role('replica')
self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', self.p.name, None))
@@ -846,7 +1013,7 @@ class TestHa(PostgresInit):
def test_is_healthiest_node(self):
self.ha.is_failsafe_mode = true
self.p.is_primary = false
self.ha.state_handler.is_primary = false
self.ha.patroni.nofailover = False
self.ha.fetch_node_status = get_node_status()
self.ha.dcs._last_failsafe = {'foo': ''}
@@ -1088,7 +1255,7 @@ class TestHa(PostgresInit):
f = Failover(0, self.p.name, '', None)
self.ha.cluster = get_cluster_initialized_with_leader(f)
self.ha.fetch_node_status = get_node_status() # accessible, in_recovery
self.assertEqual(self.ha.run_cycle(), 'manual failover: demoting myself')
self.assertEqual(self.ha.run_cycle(), 'switchover: demoting myself')
@patch('patroni.ha.Ha.demote')
def test_failover_immediately_on_zero_primary_start_timeout(self, demote):