Migrate to oslo.concurrency

Namespaces are not used anymore, so imports are for oslo_concurrency,
not oslo.concurrency.

lockutils direct call is not supported anymore, so using shipped
lockutils-wrapper instead.

Use ExternalLockFixture to set lock_path for unit testing.

Updated cache and cache/_backends module from oslo-incubator to use
oslo.concurrency and not incubator version of lockutils module.

Dropped lockutils incubator module that is now moved to oslo.concurrency. Not
dropping fixture module that includes lockutils fixture since other fixtures
are still used in the tree.

Closes-Bug: #1387092
Change-Id: I2ba2295f8f5d55f272a9d23555940586b25b5a1c

neutron/agent/linux/external_process.py

@@ -16,11 +16,11 @@ import collections
 
 import eventlet
 from oslo.config import cfg
+from oslo_concurrency import lockutils
 
 from neutron.agent.linux import ip_lib
 from neutron.agent.linux import utils
 from neutron.i18n import _LE
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log as logging
 
 LOG = logging.getLogger(__name__)

neutron/agent/linux/iptables_manager.py

@@ -24,13 +24,13 @@ import sys
 
 from oslo.config import cfg
 from oslo.utils import excutils
+from oslo_concurrency import lockutils
 
 from neutron.agent.common import config
 from neutron.agent.linux import iptables_comments as ic
 from neutron.agent.linux import utils as linux_utils
 from neutron.common import utils
 from neutron.i18n import _LE, _LW
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log as logging
 
 LOG = logging.getLogger(__name__)

neutron/common/utils.py

@@ -32,9 +32,9 @@ import uuid
 from eventlet.green import subprocess
 from oslo.config import cfg
 from oslo.utils import excutils
+from oslo_concurrency import lockutils
 
 from neutron.common import constants as q_const
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log as logging
 
 

neutron/openstack/common/cache/_backends/memory.py

@@ -15,9 +15,9 @@
 import collections
 
 from oslo.utils import timeutils
+from oslo_concurrency import lockutils
 
 from neutron.openstack.common.cache import backends
-from neutron.openstack.common import lockutils
 
 
 class MemoryBackend(backends.BaseCache):

neutron/openstack/common/cache/cache.py

@@ -20,6 +20,20 @@ Supported configuration options:
 `key_namespace`: Namespace under which keys will be created.
 """
 
+########################################################################
+#
+# THIS MODULE IS DEPRECATED
+#
+# Please refer to
+# https://etherpad.openstack.org/p/kilo-neutron-library-proposals for
+# the discussion leading to this deprecation.
+#
+# We recommend helping with the new neutron.cache library being created
+# as a wrapper for dogpile.
+#
+########################################################################
+
+
 from six.moves.urllib import parse
 from stevedore import driver
 

neutron/openstack/common/lockutils.py

@@ -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 neutron.openstack.common import fileutils
-from neutron.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("NEUTRON_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["NEUTRON_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))

neutron/plugins/cisco/cfg_agent/cfg_agent.py

@@ -22,6 +22,7 @@ from oslo.config import cfg
 from oslo import messaging
 from oslo.utils import importutils
 from oslo.utils import timeutils
+from oslo_concurrency import lockutils
 
 from neutron.agent.common import config
 from neutron.agent.linux import external_process
@@ -33,7 +34,6 @@ from neutron.common import topics
 from neutron import context as n_context
 from neutron.i18n import _LE, _LI, _LW
 from neutron import manager
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log as logging
 from neutron.openstack.common import loopingcall
 from neutron.openstack.common import periodic_task

neutron/plugins/cisco/db/l3/l3_router_appliance_db.py

@@ -15,6 +15,7 @@
 import copy
 
 from oslo.config import cfg
+from oslo_concurrency import lockutils
 from sqlalchemy.orm import exc
 from sqlalchemy.orm import joinedload
 from sqlalchemy.sql import expression as expr
@@ -31,7 +32,6 @@ from neutron.db import models_v2
 from neutron.db import portbindings_db as p_binding
 from neutron.extensions import providernet as pr_net
 from neutron.i18n import _LE, _LI
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log as logging
 from neutron.openstack.common import loopingcall
 from neutron.plugins.cisco.common import cisco_constants as c_const

neutron/plugins/ml2/drivers/cisco/apic/apic_topology.py

@@ -22,6 +22,7 @@ eventlet.monkey_patch()
 
 from oslo.config import cfg
 from oslo import messaging
+from oslo_concurrency import lockutils
 
 from neutron.agent.common import config
 from neutron.agent.linux import ip_lib
@@ -32,7 +33,6 @@ from neutron.common import utils as neutron_utils
 from neutron.db import agents_db
 from neutron.i18n import _LE, _LI
 from neutron import manager
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log as logging
 from neutron.openstack.common import periodic_task
 from neutron.openstack.common import service as svc

neutron/plugins/ml2/drivers/cisco/apic/mechanism_apic.py

@@ -17,9 +17,9 @@ from apicapi import apic_manager
 from keystoneclient.v2_0 import client as keyclient
 import netaddr
 from oslo.config import cfg
+from oslo_concurrency import lockutils
 
 from neutron.common import constants as n_constants
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log
 from neutron.plugins.common import constants
 from neutron.plugins.ml2 import driver_api as api

neutron/plugins/ml2/plugin.py

@@ -21,6 +21,7 @@ from oslo.db import exception as os_db_exception
 from oslo.serialization import jsonutils
 from oslo.utils import excutils
 from oslo.utils import importutils
+from oslo_concurrency import lockutils
 from sqlalchemy import exc as sql_exc
 from sqlalchemy.orm import exc as sa_exc
 
@@ -55,7 +56,6 @@ from neutron.extensions import portbindings
 from neutron.extensions import providernet as provider
 from neutron.i18n import _LE, _LI, _LW
 from neutron import manager
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log
 from neutron.openstack.common import uuidutils
 from neutron.plugins.common import constants as service_constants

neutron/plugins/nuage/plugin.py

@@ -19,6 +19,7 @@ import netaddr
 from oslo.config import cfg
 from oslo.utils import excutils
 from oslo.utils import importutils
+from oslo_concurrency import lockutils
 from sqlalchemy.orm import exc
 
 from neutron.api import extensions as neutron_extensions
@@ -38,7 +39,6 @@ from neutron.extensions import l3
 from neutron.extensions import portbindings
 from neutron.extensions import providernet as pnet
 from neutron.extensions import securitygroup as ext_sg
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log as logging
 from neutron.openstack.common import loopingcall
 from neutron.plugins.nuage.common import config

neutron/plugins/nuage/syncmanager.py

@@ -15,6 +15,7 @@
 
 from oslo.config import cfg
 from oslo.utils import importutils
+from oslo_concurrency import lockutils
 import sqlalchemy.orm.exc as db_exc
 
 from neutron import context as ncontext
@@ -22,7 +23,6 @@ from neutron.db import db_base_plugin_v2
 from neutron.db import extraroute_db
 from neutron.db import securitygroups_db
 from neutron.i18n import _LE, _LI, _LW
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log
 from neutron.plugins.nuage.common import config
 from neutron.plugins.nuage import nuagedb

neutron/plugins/vmware/plugins/base.py

@@ -18,6 +18,7 @@ import uuid
 from oslo.config import cfg
 from oslo.db import exception as db_exc
 from oslo.utils import excutils
+from oslo_concurrency import lockutils
 from sqlalchemy import exc as sql_exc
 from sqlalchemy.orm import exc as sa_exc
 import webob.exc
@@ -52,7 +53,6 @@ from neutron.extensions import portsecurity as psec
 from neutron.extensions import providernet as pnet
 from neutron.extensions import securitygroup as ext_sg
 from neutron.i18n import _LE, _LI, _LW
-from neutron.openstack.common import lockutils
 from neutron.openstack.common import log as logging
 from neutron.plugins.common import constants as plugin_const
 from neutron.plugins import vmware

neutron/services/advanced_service.py

@@ -13,7 +13,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from neutron.openstack.common import lockutils
+from oslo_concurrency import lockutils
+
 from neutron.openstack.common import log as logging
 
 LOG = logging.getLogger(__name__)

neutron/tests/base.py

@@ -29,6 +29,7 @@ import os.path
 import fixtures
 from oslo.config import cfg
 from oslo.messaging import conffixture as messaging_conffixture
+from oslo_concurrency.fixture import lockutils
 
 from neutron.common import config
 from neutron.common import rpc as n_rpc
@@ -85,6 +86,8 @@ class BaseTestCase(sub_base.SubBaseTestCase):
                 nuke_handlers=capture_logs,
             ))
 
+        self.useFixture(lockutils.ExternalLockFixture())
+
         self.temp_dir = self.useFixture(fixtures.TempDir()).path
         cfg.CONF.set_override('state_path', self.temp_dir)
 

neutron/tests/unit/test_security_groups_rpc.py

@@ -2515,9 +2515,6 @@ class TestSecurityGroupAgentWithIptables(base.BaseTestCase):
         super(TestSecurityGroupAgentWithIptables, self).setUp()
         config.register_root_helper(cfg.CONF)
         config.register_iptables_opts(cfg.CONF)
-        cfg.CONF.set_override(
-            'lock_path',
-            '$state_path/lock')
         set_firewall_driver(self.FIREWALL_DRIVER)
         cfg.CONF.set_override('enable_ipset', False, group='SECURITYGROUP')
         cfg.CONF.set_override('comment_iptables_rules', False, group='AGENT')

openstack-common.conf

@@ -5,7 +5,6 @@ module=eventlet_backdoor
 module=fileutils
 module=install_venv_common
 module=local
-module=lockutils
 module=log
 module=loopingcall
 module=middleware

requirements.txt

@@ -22,6 +22,7 @@ python-keystoneclient>=0.11.1
 alembic>=0.7.1
 six>=1.7.0
 stevedore>=1.1.0  # Apache-2.0
+oslo.concurrency>=0.3.0,!=0.4.0
 oslo.config>=1.6.0  # Apache-2.0
 oslo.context>=0.1.0                     # Apache-2.0
 oslo.db>=1.3.0  # Apache-2.0

run_tests.sh

@@ -196,7 +196,7 @@ function run_pep8_changed {
 }
 
 
-TESTRTESTS="python -m neutron.openstack.common.lockutils python setup.py testr"
+TESTRTESTS="python setup.py testr"
 
 if [ $never_venv -eq 0 ]
 then

tools/pretty_tox.sh

@@ -3,4 +3,4 @@
 TESTRARGS=$1
 
 exec 3>&1
-status=$(exec 4>&1 >&3; ( python -m neutron.openstack.common.lockutils python setup.py testr --slowest --testr-args="--subunit $TESTRARGS"; echo $? >&4 ) | subunit-trace -f) && exit $status
+status=$(exec 4>&1 >&3; ( python setup.py testr --slowest --testr-args="--subunit $TESTRARGS"; echo $? >&4 ) | subunit-trace -f) && exit $status

tox.ini

@@ -61,7 +61,7 @@ commands = python ./tools/check_i18n.py ./neutron ./tools/i18n_cfg.py
 
 [testenv:cover]
 commands =
-  python -m neutron.openstack.common.lockutils python setup.py testr --coverage --testr-args='{posargs}'
+  python setup.py testr --coverage --testr-args='{posargs}'
 
 [testenv:venv]
 commands = {posargs}