class _PullToPushProducer:
"""A push producer that wraps a pull producer."""
def __init__(
self, reactor: IReactorTime, producer: IPullProducer, consumer: IConsumer
):
self._clock = Clock(reactor)
self._producer = producer
self._consumer = consumer
# While running we use a looping call with a zero delay to call
# resumeProducing on given producer.
self._looping_call = None # type: Optional[LoopingCall]
# We start writing next reactor tick.
self._start_loop()
def _start_loop(self):
"""Start the looping call to"""
if not self._looping_call:
# Start a looping call which runs every tick.
self._looping_call = self._clock.looping_call(self._run_once, 0)
def stop(self):
"""Stops calling resumeProducing."""
if self._looping_call:
self._looping_call.stop()
self._looping_call = None
def pauseProducing(self):
"""Implements IPushProducer"""
self.stop()
def resumeProducing(self):
"""Implements IPushProducer"""
self._start_loop()
def stopProducing(self):
"""Implements IPushProducer"""
self.stop()
self._producer.stopProducing()
def _run_once(self):
"""Calls resumeProducing on producer once."""
try:
self._producer.resumeProducing()
except Exception:
logger.exception("Failed to call resumeProducing")
try:
self._consumer.unregisterProducer()
except Exception:
pass
self.stopProducing()
def __init__(
self,
reactor: IReactorCore,
clock: Clock,
store: LockStore,
lock_name: str,
lock_key: str,
token: str,
) -> None:
self._reactor = reactor
self._clock = clock
self._store = store
self._lock_name = lock_name
self._lock_key = lock_key
self._token = token
self._looping_call = clock.looping_call(
self._renew, _RENEWAL_INTERVAL_MS, store, lock_name, lock_key, token
)
self._dropped = False
