openstack/deb-sahara
Code Issues Proposed changes

Migrate to oslo.concurrency

Browse Source 
Change-Id: Ib50c6d1e56686e86d391c0908e65663a59d041c8
Closes-bug: #1406238
This commit is contained in:
Vitaly Gridnev 2014-12-29 14:09:28 +03:00
parent bd545f7a27
commit 00ae98c230
9 changed files with 23 additions and 628 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
etc/sahara/sahara.conf.sample
View File

@ -205,9 +205,6 @@
# List of logger=LEVEL pairs. (list value)
#default_log_levels = amqplib=WARN,qpid.messaging=INFO,stevedore=INFO,eventlet.wsgi.server=WARN,sqlalchemy=WARN,boto=WARN,suds=INFO,keystone=INFO,paramiko=WARN,requests=WARN,iso8601=WARN
# Enables or disables inter-process locks. (boolean value)
#disable_process_locking = false
# Enables data locality for hadoop cluster. Also
# enables data locality for Swift used by hadoop. If
# enabled, 'compute_topology' and 'swift_topology'
@ -250,9 +247,6 @@
# cancel job execution during this time. (integer value)
#job_canceling_timeout = 300
# Directory to use for lock files. (string value)
#lock_path = <None>
# The name of a logging configuration file. This file is appended to
# any existing logging configuration files. For details about logging
# configuration files, see the Python logging module documentation.
@ -762,6 +756,24 @@
#ringfile = /etc/oslo/matchmaker_ring.json
[oslo_concurrency]
#
# From oslo.concurrency
#
# Enables or disables inter-process locks. (boolean value)
# Deprecated group/name - [DEFAULT]/disable_process_locking
#disable_process_locking = false
# Directory to use for lock files. For security, the specified
# directory should only be writable by the user running the processes
# that need locking. Defaults to environment variable OSLO_LOCK_PATH.
# If external locks are used, a lock path must be set. (string value)
# Deprecated group/name - [DEFAULT]/lock_path
#lock_path = <None>
[oslo_messaging_amqp]
#

2
openstack-common.conf
View File

@ -1,11 +1,9 @@
[DEFAULT]
# The list of modules to copy from oslo-incubator
module=lockutils
module=log
module=periodic_task
module=policy
module=processutils
module=threadgroup
module=uuidutils

1
requirements.txt
View File

@ -13,6 +13,7 @@ jsonschema>=2.0.0,<3.0.0
keystonemiddleware>=1.0.0
lockfile>=0.8
oslo.config>=1.4.0 # Apache-2.0
oslo.concurrency>=0.3.0 # Apache-2.0
oslo.context>=0.1.0 # Apache-2.0
oslo.db>=1.1.0 # Apache-2.0
oslo.i18n>=1.0.0 # Apache-2.0

2
sahara/config.py
View File

@ -19,7 +19,6 @@ from oslo.config import cfg
from sahara import exceptions as ex
from sahara.i18n import _
from sahara.openstack.common import lockutils
from sahara.openstack.common import log
from sahara.openstack.common import periodic_task
from sahara.openstack.common import policy
@ -124,7 +123,6 @@ def list_opts():
edp_opts,
networking_opts,
db_opts,
lockutils.util_opts,
policy.policy_opts,
log.common_cli_opts,
log.generic_log_opts,

326
sahara/openstack/common/lockutils.py
View File

@ -1,326 +0,0 @@
# Copyright 2011 OpenStack Foundation.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import contextlib
import errno
import functools
import logging
import os
import shutil
import subprocess
import sys
import tempfile
import threading
import time
import weakref
from oslo.config import cfg
from sahara.openstack.common import fileutils
from sahara.openstack.common._i18n import _, _LE, _LI
LOG = logging.getLogger(__name__)
util_opts = [
cfg.BoolOpt('disable_process_locking', default=False,
help='Enables or disables inter-process locks.'),
cfg.StrOpt('lock_path',
default=os.environ.get("SAHARA_LOCK_PATH"),
help='Directory to use for lock files.')
]
CONF = cfg.CONF
CONF.register_opts(util_opts)
def set_defaults(lock_path):
cfg.set_defaults(util_opts, lock_path=lock_path)
class _FileLock(object):
"""Lock implementation which allows multiple locks, working around
issues like bugs.debian.org/cgi-bin/bugreport.cgi?bug=632857 and does
not require any cleanup. Since the lock is always held on a file
descriptor rather than outside of the process, the lock gets dropped
automatically if the process crashes, even if __exit__ is not executed.
There are no guarantees regarding usage by multiple green threads in a
single process here. This lock works only between processes. Exclusive
access between local threads should be achieved using the semaphores
in the @synchronized decorator.
Note these locks are released when the descriptor is closed, so it's not
safe to close the file descriptor while another green thread holds the
lock. Just opening and closing the lock file can break synchronisation,
so lock files must be accessed only using this abstraction.
"""
def __init__(self, name):
self.lockfile = None
self.fname = name
def acquire(self):
basedir = os.path.dirname(self.fname)
if not os.path.exists(basedir):
fileutils.ensure_tree(basedir)
LOG.info(_LI('Created lock path: %s'), basedir)
self.lockfile = open(self.fname, 'w')
while True:
try:
# Using non-blocking locks since green threads are not
# patched to deal with blocking locking calls.
# Also upon reading the MSDN docs for locking(), it seems
# to have a laughable 10 attempts "blocking" mechanism.
self.trylock()
LOG.debug('Got file lock "%s"', self.fname)
return True
except IOError as e:
if e.errno in (errno.EACCES, errno.EAGAIN):
# external locks synchronise things like iptables
# updates - give it some time to prevent busy spinning
time.sleep(0.01)
else:
raise threading.ThreadError(_("Unable to acquire lock on"
" `%(filename)s` due to"
" %(exception)s") %
{'filename': self.fname,
'exception': e})
def __enter__(self):
self.acquire()
return self
def release(self):
try:
self.unlock()
self.lockfile.close()
LOG.debug('Released file lock "%s"', self.fname)
except IOError:
LOG.exception(_LE("Could not release the acquired lock `%s`"),
self.fname)
def __exit__(self, exc_type, exc_val, exc_tb):
self.release()
def exists(self):
return os.path.exists(self.fname)
def trylock(self):
raise NotImplementedError()
def unlock(self):
raise NotImplementedError()
class _WindowsLock(_FileLock):
def trylock(self):
msvcrt.locking(self.lockfile.fileno(), msvcrt.LK_NBLCK, 1)
def unlock(self):
msvcrt.locking(self.lockfile.fileno(), msvcrt.LK_UNLCK, 1)
class _FcntlLock(_FileLock):
def trylock(self):
fcntl.lockf(self.lockfile, fcntl.LOCK_EX | fcntl.LOCK_NB)
def unlock(self):
fcntl.lockf(self.lockfile, fcntl.LOCK_UN)
if os.name == 'nt':
import msvcrt
InterProcessLock = _WindowsLock
else:
import fcntl
InterProcessLock = _FcntlLock
_semaphores = weakref.WeakValueDictionary()
_semaphores_lock = threading.Lock()
def _get_lock_path(name, lock_file_prefix, lock_path=None):
# NOTE(mikal): the lock name cannot contain directory
# separators
name = name.replace(os.sep, '_')
if lock_file_prefix:
sep = '' if lock_file_prefix.endswith('-') else '-'
name = '%s%s%s' % (lock_file_prefix, sep, name)
local_lock_path = lock_path or CONF.lock_path
if not local_lock_path:
raise cfg.RequiredOptError('lock_path')
return os.path.join(local_lock_path, name)
def external_lock(name, lock_file_prefix=None, lock_path=None):
LOG.debug('Attempting to grab external lock "%(lock)s"',
{'lock': name})
lock_file_path = _get_lock_path(name, lock_file_prefix, lock_path)
return InterProcessLock(lock_file_path)
def remove_external_lock_file(name, lock_file_prefix=None):
"""Remove an external lock file when it's not used anymore
This will be helpful when we have a lot of lock files
"""
with internal_lock(name):
lock_file_path = _get_lock_path(name, lock_file_prefix)
try:
os.remove(lock_file_path)
except OSError:
LOG.info(_LI('Failed to remove file %(file)s'),
{'file': lock_file_path})
def internal_lock(name):
with _semaphores_lock:
try:
sem = _semaphores[name]
LOG.debug('Using existing semaphore "%s"', name)
except KeyError:
sem = threading.Semaphore()
_semaphores[name] = sem
LOG.debug('Created new semaphore "%s"', name)
return sem
@contextlib.contextmanager
def lock(name, lock_file_prefix=None, external=False, lock_path=None):
"""Context based lock
This function yields a `threading.Semaphore` instance (if we don't use
eventlet.monkey_patch(), else `semaphore.Semaphore`) unless external is
True, in which case, it'll yield an InterProcessLock instance.
:param lock_file_prefix: The lock_file_prefix argument is used to provide
lock files on disk with a meaningful prefix.
:param external: The external keyword argument denotes whether this lock
should work across multiple processes. This means that if two different
workers both run a method decorated with @synchronized('mylock',
external=True), only one of them will execute at a time.
"""
int_lock = internal_lock(name)
with int_lock:
LOG.debug('Acquired semaphore "%(lock)s"', {'lock': name})
try:
if external and not CONF.disable_process_locking:
ext_lock = external_lock(name, lock_file_prefix, lock_path)
with ext_lock:
yield ext_lock
else:
yield int_lock
finally:
LOG.debug('Releasing semaphore "%(lock)s"', {'lock': name})
def synchronized(name, lock_file_prefix=None, external=False, lock_path=None):
"""Synchronization decorator.
Decorating a method like so::
@synchronized('mylock')
def foo(self, *args):
...
ensures that only one thread will execute the foo method at a time.
Different methods can share the same lock::
@synchronized('mylock')
def foo(self, *args):
...
@synchronized('mylock')
def bar(self, *args):
...
This way only one of either foo or bar can be executing at a time.
"""
def wrap(f):
@functools.wraps(f)
def inner(*args, **kwargs):
try:
with lock(name, lock_file_prefix, external, lock_path):
LOG.debug('Got semaphore / lock "%(function)s"',
{'function': f.__name__})
return f(*args, **kwargs)
finally:
LOG.debug('Semaphore / lock released "%(function)s"',
{'function': f.__name__})
return inner
return wrap
def synchronized_with_prefix(lock_file_prefix):
"""Partial object generator for the synchronization decorator.
Redefine @synchronized in each project like so::
(in nova/utils.py)
from nova.openstack.common import lockutils
synchronized = lockutils.synchronized_with_prefix('nova-')
(in nova/foo.py)
from nova import utils
@utils.synchronized('mylock')
def bar(self, *args):
...
The lock_file_prefix argument is used to provide lock files on disk with a
meaningful prefix.
"""
return functools.partial(synchronized, lock_file_prefix=lock_file_prefix)
def main(argv):
"""Create a dir for locks and pass it to command from arguments
If you run this:
python -m openstack.common.lockutils python setup.py testr <etc>
a temporary directory will be created for all your locks and passed to all
your tests in an environment variable. The temporary dir will be deleted
afterwards and the return value will be preserved.
"""
lock_dir = tempfile.mkdtemp()
os.environ["SAHARA_LOCK_PATH"] = lock_dir
try:
ret_val = subprocess.call(argv[1:])
finally:
shutil.rmtree(lock_dir, ignore_errors=True)
return ret_val
if __name__ == '__main__':
sys.exit(main(sys.argv))

289
sahara/openstack/common/processutils.py
View File

@ -1,289 +0,0 @@
# Copyright 2011 OpenStack Foundation.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
"""
System-level utilities and helper functions.
"""
import errno
import logging
import multiprocessing
import os
import random
import shlex
import signal
from eventlet.green import subprocess
from eventlet import greenthread
from oslo.utils import strutils
import six
from sahara.openstack.common._i18n import _
LOG = logging.getLogger(__name__)
class InvalidArgumentError(Exception):
def __init__(self, message=None):
super(InvalidArgumentError, self).__init__(message)
class UnknownArgumentError(Exception):
def __init__(self, message=None):
super(UnknownArgumentError, self).__init__(message)
class ProcessExecutionError(Exception):
def __init__(self, stdout=None, stderr=None, exit_code=None, cmd=None,
description=None):
self.exit_code = exit_code
self.stderr = stderr
self.stdout = stdout
self.cmd = cmd
self.description = description
if description is None:
description = _("Unexpected error while running command.")
if exit_code is None:
exit_code = '-'
message = _('%(description)s\n'
'Command: %(cmd)s\n'
'Exit code: %(exit_code)s\n'
'Stdout: %(stdout)r\n'
'Stderr: %(stderr)r') % {'description': description,
'cmd': cmd,
'exit_code': exit_code,
'stdout': stdout,
'stderr': stderr}
super(ProcessExecutionError, self).__init__(message)
class NoRootWrapSpecified(Exception):
def __init__(self, message=None):
super(NoRootWrapSpecified, self).__init__(message)
def _subprocess_setup():
# Python installs a SIGPIPE handler by default. This is usually not what
# non-Python subprocesses expect.
signal.signal(signal.SIGPIPE, signal.SIG_DFL)
def execute(*cmd, **kwargs):
"""Helper method to shell out and execute a command through subprocess.
Allows optional retry.
:param cmd: Passed to subprocess.Popen.
:type cmd: string
:param process_input: Send to opened process.
:type process_input: string
:param env_variables: Environment variables and their values that
will be set for the process.
:type env_variables: dict
:param check_exit_code: Single bool, int, or list of allowed exit
codes. Defaults to [0]. Raise
:class:`ProcessExecutionError` unless
program exits with one of these code.
:type check_exit_code: boolean, int, or [int]
:param delay_on_retry: True | False. Defaults to True. If set to True,
wait a short amount of time before retrying.
:type delay_on_retry: boolean
:param attempts: How many times to retry cmd.
:type attempts: int
:param run_as_root: True | False. Defaults to False. If set to True,
the command is prefixed by the command specified
in the root_helper kwarg.
:type run_as_root: boolean
:param root_helper: command to prefix to commands called with
run_as_root=True
:type root_helper: string
:param shell: whether or not there should be a shell used to
execute this command. Defaults to false.
:type shell: boolean
:param loglevel: log level for execute commands.
:type loglevel: int. (Should be logging.DEBUG or logging.INFO)
:returns: (stdout, stderr) from process execution
:raises: :class:`UnknownArgumentError` on
receiving unknown arguments
:raises: :class:`ProcessExecutionError`
"""
process_input = kwargs.pop('process_input', None)
env_variables = kwargs.pop('env_variables', None)
check_exit_code = kwargs.pop('check_exit_code', [0])
ignore_exit_code = False
delay_on_retry = kwargs.pop('delay_on_retry', True)
attempts = kwargs.pop('attempts', 1)
run_as_root = kwargs.pop('run_as_root', False)
root_helper = kwargs.pop('root_helper', '')
shell = kwargs.pop('shell', False)
loglevel = kwargs.pop('loglevel', logging.DEBUG)
if isinstance(check_exit_code, bool):
ignore_exit_code = not check_exit_code
check_exit_code = [0]
elif isinstance(check_exit_code, int):
check_exit_code = [check_exit_code]
if kwargs:
raise UnknownArgumentError(_('Got unknown keyword args: %r') % kwargs)
if run_as_root and hasattr(os, 'geteuid') and os.geteuid() != 0:
if not root_helper:
raise NoRootWrapSpecified(
message=_('Command requested root, but did not '
'specify a root helper.'))
cmd = shlex.split(root_helper) + list(cmd)
cmd = map(str, cmd)
sanitized_cmd = strutils.mask_password(' '.join(cmd))
while attempts > 0:
attempts -= 1
try:
LOG.log(loglevel, _('Running cmd (subprocess): %s'), sanitized_cmd)
_PIPE = subprocess.PIPE # pylint: disable=E1101
if os.name == 'nt':
preexec_fn = None
close_fds = False
else:
preexec_fn = _subprocess_setup
close_fds = True
obj = subprocess.Popen(cmd,
stdin=_PIPE,
stdout=_PIPE,
stderr=_PIPE,
close_fds=close_fds,
preexec_fn=preexec_fn,
shell=shell,
env=env_variables)
result = None
for _i in six.moves.range(20):
# NOTE(russellb) 20 is an arbitrary number of retries to
# prevent any chance of looping forever here.
try:
if process_input is not None:
result = obj.communicate(process_input)
else:
result = obj.communicate()
except OSError as e:
if e.errno in (errno.EAGAIN, errno.EINTR):
continue
raise
break
obj.stdin.close() # pylint: disable=E1101
_returncode = obj.returncode # pylint: disable=E1101
LOG.log(loglevel, 'Result was %s' % _returncode)
if not ignore_exit_code and _returncode not in check_exit_code:
(stdout, stderr) = result
sanitized_stdout = strutils.mask_password(stdout)
sanitized_stderr = strutils.mask_password(stderr)
raise ProcessExecutionError(exit_code=_returncode,
stdout=sanitized_stdout,
stderr=sanitized_stderr,
cmd=sanitized_cmd)
return result
except ProcessExecutionError:
if not attempts:
raise
else:
LOG.log(loglevel, _('%r failed. Retrying.'), sanitized_cmd)
if delay_on_retry:
greenthread.sleep(random.randint(20, 200) / 100.0)
finally:
# NOTE(termie): this appears to be necessary to let the subprocess
# call clean something up in between calls, without
# it two execute calls in a row hangs the second one
greenthread.sleep(0)
def trycmd(*args, **kwargs):
"""A wrapper around execute() to more easily handle warnings and errors.
Returns an (out, err) tuple of strings containing the output of
the command's stdout and stderr. If 'err' is not empty then the
command can be considered to have failed.
:discard_warnings True | False. Defaults to False. If set to True,
then for succeeding commands, stderr is cleared
"""
discard_warnings = kwargs.pop('discard_warnings', False)
try:
out, err = execute(*args, **kwargs)
failed = False
except ProcessExecutionError as exn:
out, err = '', six.text_type(exn)
failed = True
if not failed and discard_warnings and err:
# Handle commands that output to stderr but otherwise succeed
err = ''
return out, err
def ssh_execute(ssh, cmd, process_input=None,
addl_env=None, check_exit_code=True):
sanitized_cmd = strutils.mask_password(cmd)
LOG.debug('Running cmd (SSH): %s', sanitized_cmd)
if addl_env:
raise InvalidArgumentError(_('Environment not supported over SSH'))
if process_input:
# This is (probably) fixable if we need it...
raise InvalidArgumentError(_('process_input not supported over SSH'))
stdin_stream, stdout_stream, stderr_stream = ssh.exec_command(cmd)
channel = stdout_stream.channel
# NOTE(justinsb): This seems suspicious...
# ...other SSH clients have buffering issues with this approach
stdout = stdout_stream.read()
sanitized_stdout = strutils.mask_password(stdout)
stderr = stderr_stream.read()
sanitized_stderr = strutils.mask_password(stderr)
stdin_stream.close()
exit_status = channel.recv_exit_status()
# exit_status == -1 if no exit code was returned
if exit_status != -1:
LOG.debug('Result was %s' % exit_status)
if check_exit_code and exit_status != 0:
raise ProcessExecutionError(exit_code=exit_status,
stdout=sanitized_stdout,
stderr=sanitized_stderr,
cmd=sanitized_cmd)
return (sanitized_stdout, sanitized_stderr)
def get_worker_count():
"""Utility to get the default worker count.
@return: The number of CPUs if that can be determined, else a default
worker count of 1 is returned.
"""
try:
return multiprocessing.cpu_count()
except NotImplementedError:
return 1

4
sahara/tests/unit/db/migration/test_migrations_base.py
View File

@ -33,6 +33,8 @@ from alembic import migration
from alembic import script as alembic_script
from oslo.config import cfg
from oslo.db.sqlalchemy import test_migrations as t_m
from oslo_concurrency import lockutils
from oslo_concurrency import processutils
import six.moves.urllib.parse as urlparse
import sqlalchemy
import sqlalchemy.exc
@ -41,9 +43,7 @@ import testtools
import sahara.db.migration
from sahara.db.sqlalchemy import api as sa
from sahara.db.sqlalchemy import model_base
from sahara.openstack.common import lockutils
from sahara.openstack.common import log as logging
from sahara.openstack.common import processutils
LOG = logging.getLogger(__name__)

2
sahara/utils/crypto.py
View File

@ -15,12 +15,12 @@
import os
from oslo_concurrency import processutils
import paramiko
import six
from sahara import exceptions as ex
from sahara.i18n import _
from sahara.openstack.common import processutils
from sahara.utils import tempfiles

1
tools/config/config-generator.sahara.conf
View File

@ -2,5 +2,6 @@
namespace = sahara
namespace = oslo.db
namespace = oslo.messaging
namespace = oslo.concurrency
namespace = keystonemiddleware.auth_token
namespace = sahara_main