def __init__(self, pool_size):
# Only allow creation via get_instance
if not type(self)._SINGLETON_LOCK._is_owned():
raise AsyncArcticException(
"{} is a singleton, can't create a new instance".format(
type(self)))
pool_size = int(pool_size)
if pool_size < 1:
raise ValueError(
"{} can't be instantiated with a pool_size of {}".format(
type(self), pool_size))
# Enforce the singleton pattern
with type(self)._SINGLETON_LOCK:
if type(self)._instance is not None:
raise AsyncArcticException(
"LazySingletonTasksCoordinator is a singleton, can't create a new instance"
)
self._lock = RLock()
self._pool = None
self._pool_size = int(pool_size)
self._pool_update_hooks = []
self.alive_tasks = {}
self.is_shutdown = False
def await_termination(self, timeout=None):
with type(self)._POOL_LOCK:
if not self.is_shutdown:
raise AsyncArcticException("The workers pool has not been shutdown, please call shutdown() first.")
LazySingletonTasksCoordinator.wait_tasks(
[v[0] for v in itervalues(self.alive_tasks)],
timeout=timeout, return_when=ALL_COMPLETED, raise_exceptions=False)
with type(self)._POOL_LOCK:
self.alive_tasks = {}
def submit_task(self, is_looping, fun, *args, **kwargs):
new_id = uuid.uuid4()
shutdown_flag = Event() if is_looping else None
with type(self)._POOL_LOCK:
if self.is_shutdown:
raise AsyncArcticException("The worker pool has been shutdown and can no longer accept new requests.")
if is_looping:
new_future = self._workers_pool.submit(_looping_task, shutdown_flag, fun, *args, **kwargs)
else:
new_future = self._workers_pool.submit(_exec_task, fun, *args, **kwargs)
self.alive_tasks = {k: v for k, v in iteritems(self.alive_tasks) if not v[0].done()}
self.alive_tasks[new_id] = (new_future, shutdown_flag)
return new_id, new_future