class Worker(object):
# A worker dequeues and executes jobs from the queue
def __init__(self, host, port, db, queue_name, time_out):
self.queue = Queue(host, port, db, queue_name)
self.current_pickled_job = None
self.time_out = time_out
# Register handlers for SIGINT and SIGTERM
signal.signal(signal.SIGINT, self.handle_exit)
signal.signal(signal.SIGTERM, self.handle_exit)
def work(self):
while True:
# Block until a job can be dequeued from the queue. Then execute it
job_tuple = self.queue.dequeue(self.time_out)
if job_tuple is not None:
self.current_pickled_job, job = job_tuple
job.start(self)
else:
break
def job_finished(self, job_id):
self.current_pickled_job = None
def handle_exit(self, signal, frame):
# When the program has to shutdown before the current job is done
# executing, add it back to the front of the queue.
if self.current_pickled_job is not None:
self.queue.add_pickled_jobs_to_front(self.current_pickled_job)
sys.exit()
