diff options
| -rw-r--r-- | nova/flags.py | 2 | ||||
| -rw-r--r-- | nova/tests/test_misc.py | 48 | ||||
| -rw-r--r-- | nova/utils.py | 20 |
3 files changed, 67 insertions, 3 deletions
diff --git a/nova/flags.py b/nova/flags.py index 8cf199b2f..213d4d4e1 100644 --- a/nova/flags.py +++ b/nova/flags.py @@ -321,6 +321,8 @@ DEFINE_integer('auth_token_ttl', 3600, 'Seconds for auth tokens to linger') DEFINE_string('state_path', os.path.join(os.path.dirname(__file__), '../'), "Top-level directory for maintaining nova's state") +DEFINE_string('lock_path', os.path.join(os.path.dirname(__file__), '../'), + "Directory for lock files") DEFINE_string('logdir', None, 'output to a per-service log file in named ' 'directory') diff --git a/nova/tests/test_misc.py b/nova/tests/test_misc.py index e6da6112a..a658e4978 100644 --- a/nova/tests/test_misc.py +++ b/nova/tests/test_misc.py @@ -14,10 +14,12 @@ # License for the specific language governing permissions and limitations # under the License. +import errno import os +import select from nova import test -from nova.utils import parse_mailmap, str_dict_replace +from nova.utils import parse_mailmap, str_dict_replace, synchronized class ProjectTestCase(test.TestCase): @@ -55,3 +57,47 @@ class ProjectTestCase(test.TestCase): '%r not listed in Authors' % missing) finally: tree.unlock() + + +class LockTestCase(test.TestCase): + def test_synchronized_wrapped_function_metadata(self): + @synchronized('whatever') + def foo(): + """Bar""" + pass + self.assertEquals(foo.__doc__, 'Bar', "Wrapped function's docstring " + "got lost") + self.assertEquals(foo.__name__, 'foo', "Wrapped function's name " + "got mangled") + + def test_synchronized(self): + rpipe1, wpipe1 = os.pipe() + rpipe2, wpipe2 = os.pipe() + + @synchronized('testlock') + def f(rpipe, wpipe): + try: + os.write(wpipe, "foo") + except OSError, e: + self.assertEquals(e.errno, errno.EPIPE) + return + + rfds, _, __ = select.select([rpipe], [], [], 1) + self.assertEquals(len(rfds), 0, "The other process, which was" + " supposed to be locked, " + "wrote on its end of the " + "pipe") + os.close(rpipe) + + pid = os.fork() + if pid > 0: + os.close(wpipe1) + os.close(rpipe2) + + f(rpipe1, wpipe2) + else: + os.close(rpipe1) + os.close(wpipe2) + + f(rpipe2, wpipe1) + os._exit(0) diff --git a/nova/utils.py b/nova/utils.py index 02b71900c..3007bf19d 100644 --- a/nova/utils.py +++ b/nova/utils.py @@ -23,10 +23,14 @@ System-level utilities and helper functions. import base64 import datetime +import functools import inspect import json +import lockfile +import netaddr import os import random +import re import socket import string import struct @@ -34,8 +38,6 @@ import sys import time import types from xml.sax import saxutils -import re -import netaddr from eventlet import event from eventlet import greenthread @@ -43,11 +45,13 @@ from eventlet.green import subprocess from nova import exception from nova.exception import ProcessExecutionError +from nova import flags from nova import log as logging LOG = logging.getLogger("nova.utils") TIME_FORMAT = "%Y-%m-%dT%H:%M:%SZ" +FLAGS = flags.FLAGS def import_class(import_str): @@ -491,6 +495,18 @@ def loads(s): return json.loads(s) +def synchronized(name): + def wrap(f): + @functools.wraps(f) + def inner(*args, **kwargs): + lock = lockfile.FileLock(os.path.join(FLAGS.lock_path, + 'nova-%s.lock' % name)) + with lock: + return f(*args, **kwargs) + return inner + return wrap + + def get_from_path(items, path): """ Returns a list of items matching the specified path. Takes an XPath-like expression e.g. prop1/prop2/prop3, and for each item in items, |