Having trouble handling exceptions in Spring Integ

2020-04-18 05:14发布

问题:

I'm new to spring integration and am confused about how to send error messages to a designated error queue. I want the error message to be a header on the original message and end up in a separate queue. I read that this can be done with a header enricher, which I tried to implement but nothing is showing up in the error queue.

Also, do I need a separate exception handling class in order for the error messages to make it to the error queue or can I just throw exceptions in my transforming methods?

Here is my xml config:

<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:int="http://www.springframework.org/schema/integration"
   xmlns:int-amqp="http://www.springframework.org/schema/integration/amqp" 
   xmlns:rabbit="http://www.springframework.org/schema/rabbit" 
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:context="http://www.springframework.org/schema/context"
   xsi:schemaLocation="http://www.springframework.org/schema/beans    
                        http://www.springframework.org/schema/beans/spring-beans.xsd    
                        http://www.springframework.org/schema/integration    
                        http://www.springframework.org/schema/integration/spring-integration.xsd
                        http://www.springframework.org/schema/integration/amqp
                        http://www.springframework.org/schema/integration/amqp/spring-integration-amqp.xsd
                        http://www.springframework.org/schema/rabbit
                        http://www.springframework.org/schema/context
                        http://www.springframework.org/schema/context/spring-context.xsd
                        http://www.springframework.org/schema/rabbit/spring-rabbit.xsd">

   <rabbit:connection-factory id="connectionFactory" host="bigdata-rdp" username="myuser" password="mypass" />
   <rabbit:template id="amqpTemplate" connection-factory="connectionFactory" />
   <rabbit:admin connection-factory="connectionFactory" />
   <rabbit:queue name="first" auto-delete="false" durable="true" />
   <rabbit:queue name="second" auto-delete="false" durable="true" />
   <rabbit:queue name="errorQueue" auto-delete="false" durable="true" />

   <int:poller default="true" fixed-rate="100"/>

   <rabbit:fanout-exchange name="second-exchange" auto-delete="true" durable="true">
     <rabbit:bindings>
        <rabbit:binding queue="second" />
     </rabbit:bindings>
   </rabbit:fanout-exchange>

   <rabbit:fanout-exchange name="error-exchange" auto-delete="true" durable="true">
      <rabbit:bindings>
         <rabbit:binding queue="errorQueue" />
      </rabbit:bindings>
   </rabbit:fanout-exchange>

  <int-amqp:outbound-channel-adapter channel="messageOutputChannel" exchange-name="second-exchange"  amqp-template="amqpTemplate" />

   <int-amqp:inbound-channel-adapter channel="messageInputChannel" error-channel="errorInputChannel" queue-names="first" connection-factory="connectionFactory" concurrent-consumers="20" />

   <int-amqp:outbound-channel-adapter channel="errorOutputChannel" exchange-name="error-exchange"  amqp-template="amqpTemplate" />

   <int:channel id="messageInputChannel" />
   <int:channel id="messageOutputChannel"/>
   <int:channel id="errorInputChannel"/>

<int:service-activator input-channel="errorInputChannel" output-channel= "errorOutputChannel" method = "handleError" >
   <bean class="firstAttempt.MessageErrorHandler"/>

   <int:chain input-channel="messageInputChannel" output-channel="messageOutputChannel">
     <int:header-enricher>
    <int:error-channel ref="errorInputChannel" />
       </int:header-enricher>
            <int:transformer method = "convert" >
                <bean class="firstAttempt.JsonObjectConverter" />
            </int:transformer>
        <int:service-activator method="transform">
             <bean class="firstAttempt.Transformer" />
        </int:service-activator>
     <int:object-to-string-transformer />
   </int:chain>

</beans>

Error Class:

public class ErrorHandler {
    public String errorHandle(MessageHandlingException exception) {
        return exception.getMessage();

QualityScorer class (called by transformer):

public class QualityScorer {
    private Hashtable<String, String> table;
    private final static String csvFile = "C:\\Users\\john\\Test.csv";

public QualityScorer() throws Exception {
    table = new Hashtable<String, String>();
    initializeTable();
}

private void initializeTable() throws Exception {
     BufferedReader br = null;
      String line = "";
    String cvsSplitBy = ",";
   try {
       br = new BufferedReader(new FileReader(csvFile));
        while ((line = br.readLine()) != null) {
               String[] data = line.split(cvsSplitBy);
            if(data.length > 6 && data[1].equals("1") && data[4].equals("0") && data[5].equals("1"))
                table.putIfAbsent(data[3], data[1]);
        }
   } catch (FileNotFoundException e) {
       throw new Exception("No file found");
  } catch (IOException e) {
            e.printStackTrace();
  } finally {
        if (br != null) {
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    public float getScore(JSONObject object) throws Exception {
        float score;
        if (object == null) {
            throw new IllegalArgumentException("object");
        }
        if (!object.has("source")) {
            throw new Exception("Object does not have a source");
        }
         if (!object.has("employer")) {
            throw new Exception("Object does not have an employer");
        }
        String source = object.getString("Source");
        String employer = object.getString("employer");
            if (table.containsKey(employer) && !source.equals("packageOne")) {
               score = 1;
          } else {
                score = -1;
        }
        return score;
    }
}

Right now, the message being loaded has no source, so the program should be throwing the MessagingException to the MessageErrorHandler.

Transformer code:

public class Transformer {
 private QualityScorer qualityScorer;

 public Transformer() throws Exception {
  qualityScorer = new QualityScorer();
 }

 public JSONObject transform(JSONObject object) throws Exception {

     float score = qualityScorer.getScore(object);
     object.put("score", score);
    return object;
    }
}

All together, the program should receive a pre-loaded message from a queue, transform it and send it on to a second queue, which it does successfully if the source is provided in the pre-loaded message. I'm trying to handle errors and make it so they are sent to an error queue as a message header. This issue has been frustrating me for awhile, so help is greatly appreciated!

The error currently being shown in the stacktrace is:

java.lang.NoSuchMethodError: org.springframework.messaging.MessageHandlingException: method <init>(Lorg/springframework/messaging/Message;Ljava/lang/Throwable;)V not found
at org.springframework.integration.handler.MethodInvokingMessageProcessor.processMessage(MethodInvokingMessageProcessor.java:96)
at org.springframework.integration.handler.ServiceActivatingHandler.handleRequestMessage(ServiceActivatingHandler.java:89)
at org.springframework.integration.handler.AbstractReplyProducingMessageHandler.handleMessageInternal(AbstractReplyProducingMessageHandler.java:109)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:127)
at org.springframework.integration.handler.MessageHandlerChain$1.send(MessageHandlerChain.java:129)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:114)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:44)
at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:92)
at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutput(AbstractMessageProducingHandler.java:358)
at org.springframework.integration.handler.AbstractMessageProducingHandler.produceOutput(AbstractMessageProducingHandler.java:269)
at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutputs(AbstractMessageProducingHandler.java:186)
at org.springframework.integration.handler.AbstractReplyProducingMessageHandler.handleMessageInternal(AbstractReplyProducingMessageHandler.java:115)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:127)
at org.springframework.integration.handler.MessageHandlerChain$1.send(MessageHandlerChain.java:129)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:114)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:44)
at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:92)
at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutput(AbstractMessageProducingHandler.java:358)
at org.springframework.integration.handler.AbstractMessageProducingHandler.produceOutput(AbstractMessageProducingHandler.java:269)
at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutputs(AbstractMessageProducingHandler.java:186)
at org.springframework.integration.handler.AbstractReplyProducingMessageHandler.handleMessageInternal(AbstractReplyProducingMessageHandler.java:115)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:127)
at org.springframework.integration.handler.MessageHandlerChain.handleMessageInternal(MessageHandlerChain.java:110)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:127)
at org.springframework.integration.dispatcher.AbstractDispatcher.tryOptimizedDispatch(AbstractDispatcher.java:116)
at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:148)
at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:121)
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:89)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:423)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:373)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:114)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:44)
at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:92)
at org.springframework.integration.endpoint.MessageProducerSupport.sendMessage(MessageProducerSupport.java:188)
at org.springframework.integration.amqp.inbound.AmqpInboundChannelAdapter.access$1100(AmqpInboundChannelAdapter.java:56)
at org.springframework.integration.amqp.inbound.AmqpInboundChannelAdapter$Listener.processMessage(AmqpInboundChannelAdapter.java:246)
at org.springframework.integration.amqp.inbound.AmqpInboundChannelAdapter$Listener.onMessage(AmqpInboundChannelAdapter.java:203)
at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:822)
at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.invokeListener(AbstractMessageListenerContainer.java:745)
at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$001(SimpleMessageListenerContainer.java:97)
at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$1.invokeListener(SimpleMessageListenerContainer.java:189)
at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.invokeListener(SimpleMessageListenerContainer.java:1276)
at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.executeListener(AbstractMessageListenerContainer.java:726)
at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.doReceiveAndExecute(SimpleMessageListenerContainer.java:1219)
at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.receiveAndExecute(SimpleMessageListenerContainer.java:1189)
at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$1500(SimpleMessageListenerContainer.java:97)
at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$AsyncMessageProcessingConsumer.run(SimpleMessageListenerContainer.java:1421)
at java.lang.Thread.run(Thread.java:748)

But nothing is going to the error queue.

回答1:

When the exception is thrown, it is wrapped together with the requestMessage to the MessagingException. Your own business exception is in the cause and you can get access to the requestMessage from the MessagingException.failedMessage property.

So, it looks like you have everything you need for your use-case. Only the problem that before sending to the error-exchange you really should have some <transformer> in the error flow to properly convert that MessagingException to the proper message to send to the AMQP.