def acquire(self):
"""Acquire a lock for that task and remove any previous stale lock"""
lock = self._getLock()
if lock:
if lock.updateDate < datetime.now() - 2 * timedelta(seconds=tui.MTIME_POLL_INTERVAL):
# Stale lock, removing
TaskLock.delete(lock.id)
else:
raise YokadiException("Task %s is already locked by process %s" % (lock.task.id, lock.pid))
TaskLock(task=self.task, pid=os.getpid(), updateDate=datetime.now())
def acquire(self, pid=None, now=None):
"""Acquire a lock for that task and remove any previous stale lock"""
if now is None:
now = datetime.now()
if pid is None:
pid = os.getpid()
lock = self._getLock()
if lock:
if lock.updateDate < now - 2 * timedelta(
seconds=tui.MTIME_POLL_INTERVAL):
# Stale lock, reusing it
lock.pid = pid
lock.updateDate = now
else:
raise YokadiException(
"Task %s is already locked by process %s" %
(lock.task.id, lock.pid))
else:
# Create a lock
self.session.add(TaskLock(task=self.task, pid=pid, updateDate=now))
self.session.commit()
def release(self):
"""Release the lock for that task"""
# Only release our lock
lock = self._getLock()
if lock and lock.pid == os.getpid():
TaskLock.delete(lock.id)
def _getLock(self):
"""Retrieve the task lock if it exists (else None)"""
try:
return TaskLock.select(TaskLock.q.task == self.task).getOne()
except SQLObjectNotFound:
return None
