spring integration rabbit-mq json MessagingException - spring

Question

I am using Spring Integration to send notifications and as an error test case, I am sending in malformed JSON (a Map) and am getting MessagingException which seems to just go on and on.. not stopping.. I have to kill the Application.
So want to know how to capture this, may be via errorChannel. Code examples would be helpful.
My Spring Integration config:
<!-- channel to connect to disruption exchange -->
<int-amqp:publish-subscribe-channel id="inputChannel"
connection-factory="connectionFactory"
exchange="notification.exchange"/>
<int:json-to-object-transformer input-channel="inputChannel"
output-channel="notificationChannel"
type="java.util.Map"/>
<int:channel id="notificationChannel">
<int:interceptors>
<int:wire-tap channel="loggingChannel"/>
</int:interceptors>
</int:channel>
<int:logging-channel-adapter id="loggingChannel" log-full-message="true" logger-name="tapInbound" level="INFO"/>
<!-- depending on the deviceType route to either apnsChannel or gcmChannel -->
<int:router ref="notificationTypeRouter" input-channel="notificationChannel"/>
<!-- apple push notification channel-->
<int:channel id="apnsChannel"/>
<!-- service activator to process disruptionNotificationChannel -->
<int:service-activator input-channel="apnsChannel" ref="apnsPushNotificationService" method="pushNotification"/>
<!-- google cloud messaging notification channel-->
<int:channel id="gcmChannel"/>
<!-- service activator to process disruptionNotificationChannel -->
<int:service-activator input-channel="gcmChannel" ref="gcmPushNotificationService" method="pushNotification"/>
<!-- error channel to may be log to file or email or store to db in the future -->
<int:channel id="errorChannel"/>
<int:service-activator input-channel="errorChannel" ref="notificationErrorHandler" method="handleFailedNotification"/>
<!-- Infrastructure -->
<rabbit:connection-factory id="connectionFactory"
host="${spring.rabbitmq.host}"
port="${spring.rabbitmq.port}"
username="${spring.rabbitmq.username}"
password="${spring.rabbitmq.password}"/>
<rabbit:template id="amqpTemplate" connection-factory="connectionFactory"/>
<rabbit:admin connection-factory="connectionFactory"/>
<rabbit:fanout-exchange name="notification.exchange"/>
I also have an error handler:
public class NotificationErrorHandler {
private final Logger LOG = LoggerFactory.getLogger(NotificationErrorHandler.class);
public void handleFailedNotification(Message<MessageHandlingException> message) {
Map<String, Object> map = (Map) message.getPayload();
Notification notification = Notification.fromMap(map);
saveToBD(notification);
}
private void saveToBD(Notification notification) {
LOG.error("[Notification-Error-Handler] Couldn't Send Push notification: device='{}', type='{}', pushId='{}', message='{}', uid='{}'",
new Object[]{notification.getDevice(),
notification.getDeviceType(),
notification.getDeviceToken(),
notification.getBody(),
notification.getUid()});
}
}
This is the exception:
Caused by: org.springframework.messaging.MessagingException: Failure occured in AMQP listener while attempting to convert and dispatch Message.; nested exception is org.springframework.integration.transformer.MessageTransformationException: failed to transform message; nested exception is com.fasterxml.jackson.core.JsonParseException: Unexpected character ('}' (code 125)): was expecting double-quote to start field name
at [Source: [B#7a707c2c; line: 7, column: 2]
at org.springframework.integration.amqp.channel.AbstractSubscribableAmqpChannel$DispatchingMessageListener.onMessage(AbstractSubscribableAmqpChannel.java:202)
at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:799)
... 10 common frames omitted
Caused by: org.springframework.integration.transformer.MessageTransformationException: failed to transform message; nested exception is com.fasterxml.jackson.core.JsonParseException: Unexpected character ('}' (code 125)): was expecting double-quote to start field name
at [Source: [B#7a707c2c; line: 7, column: 2]
at org.springframework.integration.transformer.AbstractTransformer.transform(AbstractTransformer.java:44)
at org.springframework.integration.transformer.MessageTransformingHandler.handleRequestMessage(MessageTransformingHandler.java:68)
at org.springframework.integration.handler.AbstractReplyProducingMessageHandler.handleMessageInternal(AbstractReplyProducingMessageHandler.java:99)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:78)
at org.springframework.integration.dispatcher.BroadcastingDispatcher.invokeHandler(BroadcastingDispatcher.java:160)
at org.springframework.integration.dispatcher.BroadcastingDispatcher.dispatch(BroadcastingDispatcher.java:142)
at org.springframework.integration.amqp.channel.AbstractSubscribableAmqpChannel$DispatchingMessageListener.onMessage(AbstractSubscribableAmqpChannel.java:181)
... 11 common frames omitted
Caused by: com.fasterxml.jackson.core.JsonParseException: Unexpected character ('}' (code 125)): was expecting double-quote to start field name
at [Source: [B#7a707c2c; line: 7, column: 2]
at com.fasterxml.jackson.core.JsonParser._constructError(JsonParser.java:1419)
at com.fasterxml.jackson.core.base.ParserMinimalBase._reportError(ParserMinimalBase.java:508)
at com.fasterxml.jackson.core.base.ParserMinimalBase._reportUnexpectedChar(ParserMinimalBase.java:437)
Hope someone can help.
Thanks in advance
GM
Changes made as per #Gary's answer and its working now:
<!-- Infrastructure -->
<rabbit:connection-factory id="connectionFactory"
host="${spring.rabbitmq.host}"
port="${spring.rabbitmq.port}"
username="${spring.rabbitmq.username}"
password="${spring.rabbitmq.password}"/>
<rabbit:admin connection-factory="connectionFactory"/>
<rabbit:template id="amqpTemplate" connection-factory="connectionFactory"/>
<rabbit:direct-exchange name="notification.direct">
<rabbit:bindings>
<rabbit:binding queue="notification.queue" key="notification.queue"/>
</rabbit:bindings>
</rabbit:direct-exchange>
<rabbit:queue id="notification.queue" name="notification.queue"/>
<int-amqp:inbound-channel-adapter channel="inputChannel"
queue-names="notification.queue"
connection-factory="connectionFactory"
error-channel="errorChannel"/>
<int:json-to-object-transformer input-channel="inputChannel"
output-channel="notificationChannel"
type="java.util.Map"/>
<int:channel id="notificationChannel">
<int:interceptors>
<int:wire-tap channel="loggingChannel"/>
</int:interceptors>
</int:channel>
<int:logging-channel-adapter id="loggingChannel" log-full-message="true" logger-name="tapInbound" level="INFO"/>
<!-- depending on the deviceType route to either apnsChannel or gcmChannel -->
<int:router ref="notificationTypeRouter" input-channel="notificationChannel"/>
<!-- apple push notification channel-->
<int:channel id="apnsChannel"/>
<!-- service activator to process disruptionNotificationChannel -->
<int:service-activator input-channel="apnsChannel" ref="apnsPushNotificationService" method="pushNotification"/>
<!-- google cloud messaging notification channel-->
<int:channel id="gcmChannel"/>
<!-- service activator to process disruptionNotificationChannel -->
<int:service-activator input-channel="gcmChannel" ref="gcmPushNotificationService" method="pushNotification"/>
<!-- no op channel where message is logged for unknown devices -->
<int:channel id="noOpChannel"/>
<!-- service activator to process disruptionNotificationChannel -->
<int:service-activator input-channel="noOpChannel" ref="noOpPushNotificationService" method="pushNotification"/>
<!-- error channel to may be log to file or email or store to db in the future -->
<int:channel id="errorChannel"/>
<int:service-activator input-channel="errorChannel" ref="notificationErrorHandler"/>

Answer 1

Why are you starting the flow with a pub-sub channel? It's not normal to use a pub/sub channel for message distribution.
If you can use a message-driven channel adapter instead, you can add an error-channel.
You can't add an error channel to a pub-sub channel. You can, however inject an error-handler (implements org.springframework.util.ErrorHandler) and throw an AmqpRejectAndDontRequeueException when you detect a fatal error.
You can also use a Json MessageConverter in the channel instead of using a Json transformer downstream in the flow; in that case, the default error handler will detect a message conversion exception and reject the message rather than requeueing it.