async def send(self, message: Message) -> None:
"""
Awaited by the application to send ASGI `lifespan` events.
"""
message_type = message["type"]
self.logger.info("%s: '%s' event received from application.",
self.state, message_type)
if self.state is LifespanCycleState.CONNECTING:
if self.lifespan == "on":
raise LifespanFailure(
"Lifespan connection failed during startup and lifespan is 'on'."
)
# If a message is sent before the startup event is received by the
# application, then assume that lifespan is unsupported.
self.state = LifespanCycleState.UNSUPPORTED
raise LifespanUnsupported("Lifespan protocol appears unsupported.")
if message_type not in (
"lifespan.startup.complete",
"lifespan.shutdown.complete",
"lifespan.startup.failed",
"lifespan.shutdown.failed",
):
self.state = LifespanCycleState.FAILED
raise UnexpectedMessage(
f"Unexpected '{message_type}' event received.")
if self.state is LifespanCycleState.STARTUP:
if message_type == "lifespan.startup.complete":
self.startup_event.set()
elif message_type == "lifespan.startup.failed":
self.state = LifespanCycleState.FAILED
self.startup_event.set()
message = message.get("message", "")
raise LifespanFailure(f"Lifespan startup failure. {message}")
elif self.state is LifespanCycleState.SHUTDOWN:
if message_type == "lifespan.shutdown.complete":
self.shutdown_event.set()
elif message_type == "lifespan.shutdown.failed":
self.state = LifespanCycleState.FAILED
self.shutdown_event.set()
message = message.get("message", "")
raise LifespanFailure(f"Lifespan shutdown failure. {message}")
async def shutdown(self) -> None:
"""
Pushes the `lifespan` shutdown event to application queue and handles errors.
"""
self.logger.info("Waiting for application shutdown.")
await self.app_queue.put({"type": "lifespan.shutdown"})
await self.shutdown_event.wait()
if self.state is LifespanCycleState.FAILED:
raise LifespanFailure(self.exception)
async def send(self, message: Message) -> None:
if not self.is_supported:
raise LifespanFailure("Lifespan unsupported.")
message_type = message["type"]
if message_type == "lifespan.startup.complete":
self.startup_event.set()
elif message_type == "lifespan.shutdown.complete":
self.shutdown_event.set()
else:
raise RuntimeError(
f"Expected lifespan message type, received: {message_type}")
async def startup(self) -> None:
"""
Pushes the `lifespan` startup event to application queue and handles errors.
"""
self.logger.info("Waiting for application startup.")
await self.app_queue.put({"type": "lifespan.startup"})
await self.startup_event.wait()
if self.state is LifespanCycleState.FAILED:
raise LifespanFailure(self.exception)
if not self.exception:
self.logger.info("Application startup complete.")
else:
self.logger.info("Application startup failed.")