CODEWITHSUNDEEP
spring-integration
Marvin
Marvin

Reputation: 1706

service-activator activated only for half messages

I am using a (already set up) Spring Integration worfklow in which I try to add a service-activator that will basically count messages.

In this example I log the payload of the message but only for debugging purposes.

<bean id="messageCounterActivator" class="com.my.company.activators.MessageCounterActivator"/>
<bean id="jmsQueue2" class="com.ibm.mq.jms.MQQueue" depends-on="jmsConnectionFactory">...</bean>

<int:channel id="channelMQ_MQ" ></int:channel>
<int:service-activator input-channel="channelMQ_MQ"  method="countMessage" ref="messageCounterActivator"/>

<int-jms:message-driven-channel-adapter id="jmsIn" channel="channelMQ_MQ" destination="jmsQueue"/>
        
<int-jms:outbound-channel-adapter   channel="channelMQ_MQ" 
                                    id="jmsOut2" 
                                    destination="jmsQueue2" 
                                    connection-factory="connectionFactoryCaching2" 
                                    delivery-persistent="true" 
                                    explicit-qos-enabled="true" 
                                    session-transacted="true" />

And from the activator bean:

public Message<?> countMessage(Message<?> message) {
    LOG.debug("=> " + message.getPayload());
    someCounter.increment();
    return message;
}

Once this bidge is up, it works well : all messages are routed from A to B (MqSeries => MqSeries), and the counter is updated.... every 2 messages!

MessageCounterActivator - => message 1
MessageCounterActivator - => message 3
MessageCounterActivator - => message 5
MessageCounterActivator - => message 7
MessageCounterActivator - => message 9
MessageCounterActivator - => message 11
MessageCounterActivator - => message 13
MessageCounterActivator - => message 15
MessageCounterActivator - => message 17
MessageCounterActivator - => message 19

This is very odd to me, but I suspect some embedded activator/listener is in competition with my service-activator (I read from some posts here that when 2 activators, including logger ones, are active at once : you may have such behavior). Maybe it's because I have 2 channel adapters? I don't see here who is the competitor here.

Any idea how to have my activator working the right way?

Upvotes: 0

Views: 83

Answers (1)

Artem Bilan
Artem Bilan

Reputation: 121177

I would say your counting logic is not a part of main flow. So, better to look into a wire-tap pattern and consider to use an <int:outbound-channel-adapter> instead. Just because you not going to return anything from that counting method.

Another approach for calling different endpoints for the same message is an <int:publish-subscribe-channel>.

Right now you declare a DirectChannel with that <int:channel id="channelMQ_MQ">, which has a round-robing distribution strategy by default for its subscribers. That's exactly why you see that odd-even behavior for your subscribers.

Not sure why you are missing that, but you indeed have two subscribers for this direct channel:

<int:service-activator input-channel="channelMQ_MQ"

<int-jms:outbound-channel-adapter   channel="channelMQ_MQ"

See more in docs: https://docs.spring.io/spring-integration/docs/current/reference/html/core.html#channel-implementations-directchannel

Upvotes: 1

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