def start(self, poll_timeout=0.02):
"""
Start the engine.
This method blocks until the engine is stopped. It should be
called after your asynchronous application has been fully
initialised and is ready to start.
Args:
poll_timeout: The timeout to pass to engine.poll().
Raises:
SystemExit
"""
if self._shutdown:
self._shutdown = False
return
if self._running:
return
else:
self._running = True
# Initialise engine.
log.info("Starting engine.")
Publisher.instance().publish("pants.engine.start")
# Main loop.
try:
log.info("Entering main loop.")
while not self._shutdown:
self.poll(poll_timeout)
except KeyboardInterrupt:
pass
except SystemExit:
raise
except Exception:
log.exception("Uncaught exception in main loop.")
finally:
# Graceful shutdown.
log.info("Stopping engine.")
Publisher.instance().publish("pants.engine.stop")
log.info("Shutting down.")
self._shutdown = False
self._running = False
"engine", # Core
"Client", "Connection", "Server", # Networking
"event", "publish", "subscribe", "unsubscribe", # Publisher
"callback", "loop", "cycle", "defer", # Scheduling
]
###############################################################################
# Properties
###############################################################################
#: Alias for pants.engine.Engine.instance
engine = Engine.instance()
#: Alias for pants.publisher.Publisher.instance
publisher = Publisher.instance()
###############################################################################
# Functions
###############################################################################
#: Alias for pants.publisher.Publisher.instance().event
event = publisher.event
#: Alias for pants.publisher.Publisher.instance().publish
publish = publisher.publish
#: Alias for pants.publisher.Publisher.instance().subscribe
subscribe = publisher.subscribe
