Files
patroni/patroni/postgresql/bootstrap.py
T
Alexander Kukushkin ced75cfe12 Bump pyright and "solve" reported "issues"
Most of them are related to partially unknown types of values from empty
dict or list. To solve it for the empty dict we use `EMPTY_DICT` object of
newly introduced `_FrozenDict` class.
2024-04-02 15:15:52 +02:00

481 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 ..collections import EMPTY_DICT
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 EMPTY_DICT).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 EMPTY_DICT).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