from oslo_utils import strutils
import six
from taskflow.engines.action_engine import builder
from taskflow.engines.action_engine import compiler
from taskflow.engines.action_engine import executor
from taskflow.engines.action_engine import runtime
from taskflow.engines import base
from taskflow import exceptions as exc
from taskflow import logging
from taskflow import states
from taskflow import storage
from taskflow.types import failure
from taskflow.utils import misc
LOG = logging.getLogger(__name__)
@contextlib.contextmanager
def _start_stop(task_executor, retry_executor):
# A teenie helper context manager to safely start/stop engine executors...
task_executor.start()
try:
retry_executor.start()
try:
yield (task_executor, retry_executor)
finally:
retry_executor.stop()
finally:
task_executor.stop()
import errno
import os
import threading
import time
from oslo_utils import importutils
import six
from taskflow import logging
from taskflow.utils import misc
# Used for the reader-writer lock get the right thread 'hack' (needed below).
eventlet = importutils.try_import('eventlet')
eventlet_patcher = importutils.try_import('eventlet.patcher')
LOG = logging.getLogger(__name__)
@contextlib.contextmanager
def try_lock(lock):
"""Attempts to acquire a lock, and auto releases if acquired (on exit)."""
# NOTE(harlowja): the keyword argument for 'blocking' does not work
# in py2.x and only is fixed in py3.x (this adjustment is documented
# and/or debated in http://bugs.python.org/issue10789); so we'll just
# stick to the format that works in both (oddly the keyword argument
# works in py2.x but only with reentrant locks).
was_locked = lock.acquire(False)
try:
yield was_locked
finally:
if was_locked:
