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patroni/patroni/postgresql/bootstrap.py
T
zhjwpkuandGitHub e131065d74 rename citus_handler to mpp_handler (#2991)
obey the following 5 meanings of terminology _cluster_ in Patroni.

1. PostgreSQL cluster: a cluster of postgresql instances which have the same system identifier.
2. MPP cluster: a cluster of PostgreSQL clusters that one of them acts as Coodinator and others act as workers.
3. Coordinator cluster: a PostgreSQL cluster which act the role of 'coordinator' within a MPP cluster.
4. Worker cluster: a PostgreSQL cluster which act the role 'worker' within a MPP cluster.
5. Patroni cluster: all cluster managed by Patroni can be called Patroni cluster, but we usually use this term to refering a single PostgreSQL cluster or an MPP cluster.
2024-02-28 06:16:20 +01:00

480 lines
23 KiB
Python

import logging
import os
import shlex
import tempfile
import time
from typing import Any, Callable, Dict, List, Optional, Union, Tuple, TYPE_CHECKING
from ..async_executor import CriticalTask
from ..dcs import Leader, Member, RemoteMember
from ..psycopg import quote_ident, quote_literal
from ..utils import deep_compare, unquote
if TYPE_CHECKING: # pragma: no cover
from . import Postgresql
logger = logging.getLogger(__name__)
class Bootstrap(object):
def __init__(self, postgresql: 'Postgresql') -> None:
self._postgresql = postgresql
self._running_custom_bootstrap = False
@property
def running_custom_bootstrap(self) -> bool:
return self._running_custom_bootstrap
@property
def keep_existing_recovery_conf(self) -> bool:
return self._running_custom_bootstrap and self._keep_existing_recovery_conf
@staticmethod
def process_user_options(tool: str,
options: Union[Any, Dict[str, str], List[Union[str, Dict[str, Any]]]],
not_allowed_options: Tuple[str, ...],
error_handler: Callable[[str], None]) -> List[str]:
"""Format *options* in a list or dictionary format into command line long form arguments.
.. note::
The format of the output of this method is to prepare arguments for use in the ``initdb``
method of `self._postgres`.
:Example:
The *options* can be defined as a dictionary of key, values to be converted into arguments:
>>> Bootstrap.process_user_options('foo', {'foo': 'bar'}, (), print)
['--foo=bar']
Or as a list of single string arguments
>>> Bootstrap.process_user_options('foo', ['yes'], (), print)
['--yes']
Or as a list of key, value options
>>> Bootstrap.process_user_options('foo', [{'foo': 'bar'}], (), print)
['--foo=bar']
Or a combination of single and key, values
>>> Bootstrap.process_user_options('foo', ['yes', {'foo': 'bar'}], (), print)
['--yes', '--foo=bar']
Options that contain spaces are passed as is to ``subprocess.call``
>>> Bootstrap.process_user_options('foo', [{'foo': 'bar baz'}], (), print)
['--foo=bar baz']
Options that are quoted will be unquoted, so the quotes aren't interpreted
literally by the postgres command
>>> Bootstrap.process_user_options('foo', [{'foo': '"bar baz"'}], (), print)
['--foo=bar baz']
.. note::
The *error_handler* is called when any of these conditions are met:
* Key, value dictionaries in the list form contains multiple keys.
* If a key is listed in *not_allowed_options*.
* If the options list is not in the required structure.
:param tool: The name of the tool used in error reports to *error_handler*
:param options: Options to parse as a list of key, values or single values, or a dictionary
:param not_allowed_options: List of keys that cannot be used in the list of key, value formatted options
:param error_handler: A function which will be called when an error condition is encountered
:returns: List of long form arguments to pass to the named tool
"""
user_options: List[str] = []
def option_is_allowed(name: str) -> bool:
ret = name not in not_allowed_options
if not ret:
error_handler('{0} option for {1} is not allowed'.format(name, tool))
return ret
if isinstance(options, dict):
for key, val in options.items():
if key and val:
user_options.append('--{0}={1}'.format(key, unquote(val)))
elif isinstance(options, list):
for opt in options:
if isinstance(opt, str) and option_is_allowed(opt):
user_options.append('--{0}'.format(opt))
elif isinstance(opt, dict):
keys = list(opt.keys())
if len(keys) == 1 and isinstance(opt[keys[0]], str) and option_is_allowed(keys[0]):
user_options.append('--{0}={1}'.format(keys[0], unquote(opt[keys[0]])))
else:
error_handler('Error when parsing {0} key-value option {1}: only one key-value is allowed'
' and value should be a string'.format(tool, opt[keys[0]]))
else:
error_handler('Error when parsing {0} option {1}: value should be string value'
' or a single key-value pair'.format(tool, opt))
else:
error_handler('{0} options must be list or dict'.format(tool))
return user_options
def _initdb(self, config: Any) -> bool:
self._postgresql.set_state('initializing new cluster')
not_allowed_options = ('pgdata', 'nosync', 'pwfile', 'sync-only', 'version')
def error_handler(e: str) -> None:
raise Exception(e)
options = self.process_user_options('initdb', config or [], not_allowed_options, error_handler)
pwfile = None
if self._postgresql.config.superuser:
if 'username' in self._postgresql.config.superuser:
options.append('--username={0}'.format(self._postgresql.config.superuser['username']))
if 'password' in self._postgresql.config.superuser:
(fd, pwfile) = tempfile.mkstemp()
os.write(fd, self._postgresql.config.superuser['password'].encode('utf-8'))
os.close(fd)
options.append('--pwfile={0}'.format(pwfile))
ret = self._postgresql.initdb(*options)
if pwfile:
os.remove(pwfile)
if ret:
self._postgresql.configure_server_parameters()
else:
self._postgresql.set_state('initdb failed')
return ret
def _post_restore(self) -> None:
self._postgresql.config.restore_configuration_files()
self._postgresql.configure_server_parameters()
# make sure there is no trigger file or postgres will be automatically promoted
trigger_file = self._postgresql.config.triggerfile_good_name
trigger_file = (self._postgresql.config.get('recovery_conf') or {}).get(trigger_file) or 'promote'
trigger_file = os.path.abspath(os.path.join(self._postgresql.data_dir, trigger_file))
if os.path.exists(trigger_file):
os.unlink(trigger_file)
def _custom_bootstrap(self, config: Any) -> bool:
"""Bootstrap a fresh Patroni cluster using a custom method provided by the user.
:param config: configuration used for running a custom bootstrap method. It comes from the Patroni YAML file,
so it is expected to be a :class:`dict`.
.. note::
*config* must contain a ``command`` key, which value is the command or script to perform the custom
bootstrap procedure. The exit code of the ``command`` dictates if the bootstrap succeeded or failed.
When calling ``command``, Patroni will pass the following arguments to the ``command`` call:
* ``--scope``: contains the value of ``scope`` configuration;
* ``--data_dir``: contains the value of the ``postgresql.data_dir`` configuration.
You can avoid that behavior by filling the optional key ``no_params`` with the value ``False`` in the
configuration file, which will instruct Patroni to not pass these parameters to the ``command`` call.
Besides that, a couple more keys are supported in *config*, but optional:
* ``keep_existing_recovery_conf``: if ``True``, instruct Patroni to not remove the existing
``recovery.conf`` (PostgreSQL <= 11), to not discard recovery parameters from the configuration
(PostgreSQL >= 12), and to not remove the files ``recovery.signal`` or ``standby.signal``
(PostgreSQL >= 12). This is specially useful when you are restoring backups through tools like
pgBackRest and Barman, in which case they generated the appropriate recovery settings for you;
* ``recovery_conf``: a section containing a map, where each key is the name of a recovery related
setting, and the value is the value of the corresponding setting.
Any key/value other than the ones that were described above will be interpreted as additional arguments for
the ``command`` call. They will all be added to the call in the format ``--key=value``.
:returns: ``True`` if the bootstrap was successful, i.e. the execution of the custom ``command`` from *config*
exited with code ``0``, ``False`` otherwise.
"""
self._postgresql.set_state('running custom bootstrap script')
params = [] if config.get('no_params') else ['--scope=' + self._postgresql.scope,
'--datadir=' + self._postgresql.data_dir]
# Add custom parameters specified by the user
reserved_args = {'command', 'no_params', 'keep_existing_recovery_conf', 'recovery_conf', 'scope', 'datadir'}
params += [f"--{arg}={val}" for arg, val in config.items() if arg not in reserved_args]
try:
logger.info('Running custom bootstrap script: %s', config['command'])
if self._postgresql.cancellable.call(shlex.split(config['command']) + params) != 0:
self._postgresql.set_state('custom bootstrap failed')
return False
except Exception:
logger.exception('Exception during custom bootstrap')
return False
self._post_restore()
if 'recovery_conf' in config:
self._postgresql.config.write_recovery_conf(config['recovery_conf'])
elif not self.keep_existing_recovery_conf:
self._postgresql.config.remove_recovery_conf()
return True
def call_post_bootstrap(self, config: Dict[str, Any]) -> bool:
"""
runs a script after initdb or custom bootstrap script is called and waits until completion.
"""
cmd = config.get('post_bootstrap') or config.get('post_init')
if cmd:
r = self._postgresql.connection_pool.conn_kwargs
connstring = self._postgresql.config.format_dsn(r, True)
if 'host' not in r:
# https://www.postgresql.org/docs/current/static/libpq-pgpass.html
# A host name of localhost matches both TCP (host name localhost) and Unix domain socket
# (pghost empty or the default socket directory) connections coming from the local machine.
r['host'] = 'localhost' # set it to localhost to write into pgpass
env = self._postgresql.config.write_pgpass(r)
env['PGOPTIONS'] = '-c synchronous_commit=local -c statement_timeout=0'
try:
ret = self._postgresql.cancellable.call(shlex.split(cmd) + [connstring], env=env)
except OSError:
logger.error('post_init script %s failed', cmd)
return False
if ret != 0:
logger.error('post_init script %s returned non-zero code %d', cmd, ret)
return False
return True
def create_replica(self, clone_member: Union[Leader, Member, None]) -> Optional[int]:
"""
create the replica according to the replica_method
defined by the user. this is a list, so we need to
loop through all methods the user supplies
"""
self._postgresql.set_state('creating replica')
self._postgresql.schedule_sanity_checks_after_pause()
is_remote_member = isinstance(clone_member, RemoteMember)
# get list of replica methods either from clone member or from
# the config. If there is no configuration key, or no value is
# specified, use basebackup
replica_methods = (clone_member.create_replica_methods if is_remote_member
else self._postgresql.create_replica_methods) or ['basebackup']
if clone_member and clone_member.conn_url:
r = clone_member.conn_kwargs(self._postgresql.config.replication)
# add the credentials to connect to the replica origin to pgpass.
env = self._postgresql.config.write_pgpass(r)
connstring = self._postgresql.config.format_dsn(r, True)
else:
connstring = ''
env = os.environ.copy()
# if we don't have any source, leave only replica methods that work without it
replica_methods = [r for r in replica_methods
if self._postgresql.replica_method_can_work_without_replication_connection(r)]
# go through them in priority order
ret = 1
for replica_method in replica_methods:
if self._postgresql.cancellable.is_cancelled:
break
method_config = self._postgresql.replica_method_options(replica_method)
# if the method is basebackup, then use the built-in
if replica_method == "basebackup":
ret = self.basebackup(connstring, env, method_config)
if ret == 0:
logger.info("replica has been created using basebackup")
# if basebackup succeeds, exit with success
break
else:
if not self._postgresql.data_directory_empty():
if method_config.get('keep_data', False):
logger.info('Leaving data directory uncleaned')
else:
self._postgresql.remove_data_directory()
cmd = replica_method
# user-defined method; check for configuration
# not required, actually
if method_config:
# look to see if the user has supplied a full command path
# if not, use the method name as the command
cmd = method_config.pop('command', cmd)
# add the default parameters
if not method_config.get('no_params', False):
method_config.update({"scope": self._postgresql.scope,
"role": "replica",
"datadir": self._postgresql.data_dir,
"connstring": connstring})
else:
for param in ('no_params', 'no_master', 'no_leader', 'keep_data'):
method_config.pop(param, None)
params = ["--{0}={1}".format(arg, val) for arg, val in method_config.items()]
try:
# call script with the full set of parameters
ret = self._postgresql.cancellable.call(shlex.split(cmd) + params, env=env)
# if we succeeded, stop
if ret == 0:
logger.info('replica has been created using %s', replica_method)
break
else:
logger.error('Error creating replica using method %s: %s exited with code=%s',
replica_method, cmd, ret)
except Exception:
logger.exception('Error creating replica using method %s', replica_method)
ret = 1
self._postgresql.set_state('stopped')
return ret
def basebackup(self, conn_url: str, env: Dict[str, str], options: Dict[str, Any]) -> Optional[int]:
# creates a replica data dir using pg_basebackup.
# this is the default, built-in create_replica_methods
# tries twice, then returns failure (as 1)
# uses "stream" as the xlog-method to avoid sync issues
# supports additional user-supplied options, those are not validated
maxfailures = 2
ret = 1
not_allowed_options = ('pgdata', 'format', 'wal-method', 'xlog-method', 'gzip',
'version', 'compress', 'dbname', 'host', 'port', 'username', 'password')
user_options = self.process_user_options('basebackup', options, not_allowed_options, logger.error)
for bbfailures in range(0, maxfailures):
if self._postgresql.cancellable.is_cancelled:
break
if not self._postgresql.data_directory_empty():
self._postgresql.remove_data_directory()
try:
ret = self._postgresql.cancellable.call([self._postgresql.pgcommand('pg_basebackup'),
'--pgdata=' + self._postgresql.data_dir, '-X', 'stream',
'--dbname=' + conn_url] + user_options, env=env)
if ret == 0:
break
else:
logger.error('Error when fetching backup: pg_basebackup exited with code=%s', ret)
except Exception as e:
logger.error('Error when fetching backup with pg_basebackup: %s', e)
if bbfailures < maxfailures - 1:
logger.warning('Trying again in 5 seconds')
time.sleep(5)
return ret
def clone(self, clone_member: Union[Leader, Member, None]) -> bool:
"""
- initialize the replica from an existing member (primary or replica)
- initialize the replica using the replica creation method that
works without the replication connection (i.e. restore from on-disk
base backup)
"""
ret = self.create_replica(clone_member) == 0
if ret:
self._post_restore()
return ret
def bootstrap(self, config: Dict[str, Any]) -> bool:
""" Initialize a new node from scratch and start it. """
pg_hba = config.get('pg_hba', [])
method = config.get('method') or 'initdb'
if method != 'initdb' and method in config and 'command' in config[method]:
self._keep_existing_recovery_conf = config[method].get('keep_existing_recovery_conf')
self._running_custom_bootstrap = True
do_initialize = self._custom_bootstrap
else:
method = 'initdb'
do_initialize = self._initdb
return do_initialize(config.get(method)) and self._postgresql.config.append_pg_hba(pg_hba) \
and self._postgresql.config.save_configuration_files() and bool(self._postgresql.start())
def create_or_update_role(self, name: str, password: Optional[str], options: List[str]) -> None:
options = list(map(str.upper, options))
if 'NOLOGIN' not in options and 'LOGIN' not in options:
options.append('LOGIN')
if password:
options.extend(['PASSWORD', quote_literal(password)])
sql = """DO $$
BEGIN
SET local synchronous_commit = 'local';
PERFORM * FROM pg_catalog.pg_authid WHERE rolname = {0};
IF FOUND THEN
ALTER ROLE {1} WITH {2};
ELSE
CREATE ROLE {1} WITH {2};
END IF;
END;$$""".format(quote_literal(name), quote_ident(name, self._postgresql.connection()), ' '.join(options))
self._postgresql.query('SET log_statement TO none')
self._postgresql.query('SET log_min_duration_statement TO -1')
self._postgresql.query("SET log_min_error_statement TO 'log'")
self._postgresql.query("SET pg_stat_statements.track_utility to 'off'")
try:
self._postgresql.query(sql)
finally:
self._postgresql.query('RESET log_min_error_statement')
self._postgresql.query('RESET log_min_duration_statement')
self._postgresql.query('RESET log_statement')
self._postgresql.query('RESET pg_stat_statements.track_utility')
def post_bootstrap(self, config: Dict[str, Any], task: CriticalTask) -> Optional[bool]:
try:
postgresql = self._postgresql
superuser = postgresql.config.superuser
if 'username' in superuser and 'password' in superuser:
self.create_or_update_role(superuser['username'], superuser['password'], ['SUPERUSER'])
task.complete(self.call_post_bootstrap(config))
if task.result:
replication = postgresql.config.replication
self.create_or_update_role(replication['username'], replication.get('password'), ['REPLICATION'])
rewind = postgresql.config.rewind_credentials
if not deep_compare(rewind, superuser):
self.create_or_update_role(rewind['username'], rewind.get('password'), [])
for f in ('pg_ls_dir(text, boolean, boolean)', 'pg_stat_file(text, boolean)',
'pg_read_binary_file(text)', 'pg_read_binary_file(text, bigint, bigint, boolean)'):
sql = """DO $$
BEGIN
SET local synchronous_commit = 'local';
GRANT EXECUTE ON function pg_catalog.{0} TO {1};
END;$$""".format(f, quote_ident(rewind['username'], postgresql.connection()))
postgresql.query(sql)
if config.get('users'):
logger.warning('User creation via "bootstrap.users" will be removed in v4.0.0')
for name, value in (config.get('users') or {}).items():
if all(name != a.get('username') for a in (superuser, replication, rewind)):
self.create_or_update_role(name, value.get('password'), value.get('options', []))
# We were doing a custom bootstrap instead of running initdb, therefore we opened trust
# access from certain addresses to be able to reach cluster and change password
if self._running_custom_bootstrap:
self._running_custom_bootstrap = False
# If we don't have custom configuration for pg_hba.conf we need to restore original file
if not postgresql.config.get('pg_hba'):
if os.path.exists(postgresql.config.pg_hba_conf):
os.unlink(postgresql.config.pg_hba_conf)
postgresql.config.restore_configuration_files()
postgresql.config.write_postgresql_conf()
postgresql.config.replace_pg_ident()
# at this point there should be no recovery.conf
postgresql.config.remove_recovery_conf()
if postgresql.config.hba_file:
postgresql.restart()
else:
postgresql.config.replace_pg_hba()
if postgresql.pending_restart_reason:
postgresql.restart()
else:
postgresql.reload()
time.sleep(1) # give a time to postgres to "reload" configuration files
postgresql.connection().close() # close connection to reconnect with a new password
else: # initdb
# We may want create database and extension for some MPP clusters
self._postgresql.mpp_handler.bootstrap()
except Exception:
logger.exception('post_bootstrap')
task.complete(False)
return task.result