[CAMEL-7922] MQTT endpoint misses QoS > 0 messages due to startup timing issue

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.14.0
• Fix Version/s: 2.13.4, 2.14.1, 2.15.0
• Component/s: camel-mqtt
• Estimated Complexity: Unknown
• Assignee: Willem Jiang
• Reporter: Davy De Waele
• Created: 16/Oct/14 20:37
• Updated: 20/Nov/14 09:11
• Resolved: 20/Nov/14 09:11

Description

When the MQTT Endpoint is started the MQTT connection is immediately established, causing an immediate influx of persisted messages (put on the topic when the client was not available).

Issue is that at this point, most likely no consumers are available yet to process these messages.

Receiving a PUBLISH message

Publish message are received without any consumers. Result : msg with QoS > 0 that were put on the topic while the client was not connected are never processed.

Daemon Thread [hawtdispatch-DEFAULT-3] (Suspended (breakpoint at line 815 in CallbackConnection))	
	CallbackConnection.toReceiver(PUBLISH) line: 815	
	CallbackConnection.processFrame(MQTTFrame) line: 732	
	CallbackConnection.access$1500(CallbackConnection, MQTTFrame) line: 51	
	CallbackConnection$6.onTransportCommand(Object) line: 392	
	TcpTransport.drainInbound() line: 709	
	TcpTransport$6.run() line: 588	
	NioDispatchSource$3.run() line: 209	
	SerialDispatchQueue.run() line: 100	
	SimpleThread.run() line: 77	

No consumers registered yet

Only when this finishes will Camel be able to process the messages.

Daemon Thread [localhost-startStop-1] (Suspended (breakpoint at line 164 in MQTTEndpoint))	
	owns: SpringCamelContext  (id=92)	
	owns: Object  (id=143)	
	owns: StandardContext  (id=144)	
	MQTTEndpoint.addConsumer(MQTTConsumer) line: 164	
	MQTTConsumer.doStart() line: 35	
	MQTTConsumer(ServiceSupport).start() line: 61	
	SpringCamelContext(DefaultCamelContext).startService(Service) line: 2158	
	SpringCamelContext(DefaultCamelContext).doStartOrResumeRouteConsumers(Map<Integer,DefaultRouteStartupOrder>, boolean, boolean) line: 2452	
	SpringCamelContext(DefaultCamelContext).doStartRouteConsumers(Map<Integer,DefaultRouteStartupOrder>, boolean) line: 2388	
	SpringCamelContext(DefaultCamelContext).safelyStartRouteServices(boolean, boolean, boolean, boolean, Collection<RouteService>) line: 2318	
	SpringCamelContext(DefaultCamelContext).doStartOrResumeRoutes(Map<String,RouteService>, boolean, boolean, boolean, boolean) line: 2091	
	SpringCamelContext(DefaultCamelContext).doStartCamel() line: 1951	
	SpringCamelContext(DefaultCamelContext).doStart() line: 1777	

These messages will never be picked up.

Perhaps it's more the responsibility of the consumer / producer to start a connection when they get attached to the endpoint ?