WSO2 Message Broker 3.0.0 and WS-Eventing

Question

I am testing WSO2 Message Broker 3.0 and I miss the functionality of subscribing WS endpoints to topics. Can this functionality be activated with MB 3.0 as it was in MB 2.x? I am trying to implement reliable (queued) topic subscription for WS-Endpoints. How can it be implemented using WSO2 MB 3.0?

Answer 1

WS-Eventing removed from WSO2 MB 3.0.0. But you can achieve this by integrating WSO2 MB with WSO2 ESB. This is widely used common integration pattern for reliable messaging and also you could modify/mediate message as necessary in WSO2 ESB before send to actual backend. Let's see how we can do this.

I'll show you how to integrate WSO2 ESB with WSO2 MB in local machine.

• Download WSO2 ESB 4.9.0 (latest version) from http://wso2.com/products/enterprise-service-bus/. Hope you have WSO2 MB 3.0.0 (latest version) already in hand.

• Once you extract, open wso2esb-4.9.0/repository/conf/carbon.xml file and change <Offset>0</Offset> to <Offset>1</Offset>. This allow you to run multiple carbon servers in single machine. You can access management console https://localhost:9444/carbon

• Open wso2esb-4.9.0/repository/conf/axis2/axis2.xml and uncomment section after <!--Uncomment this and configure as appropriate for JMS transport support with WSO2 MB 2.x.x--> for JMS transport receiver and section after <!--uncomment this and configure to use connection pools for sending messages--> for JMS transport sender.

• Copy andes-client-3.0.1.jar geronimo-jms_1.1_spec-1.1.0.wso2v1.jar org.wso2.securevault-1.0.0-wso2v2.jar in wso2mb-3.0.0/client-lib to wso2esb-4.9.0/repository/components/lib

• Add below entries to wso2esb-4.9.0/repository/conf/jndi.properties

  connectionfactory.QueueConnectionFactory = amqp://admin:admin@clientID/carbon?brokerlist='tcp://localhost:5672'

  connectionfactory.TopicConnectionFactory = amqp://admin:admin@clientID/carbon?brokerlist='tcp://localhost:5672'

  topic.MyDurableTopic = MyDurbleTopic

• First start the WSO2 MB and then start WSO2 ESB by running wso2server.sh or wso2server.bat in bin folder depending on OS you are using

• Integration completed.

Let's see how we can create JMS listener proxy which creates durable subscription in WSO2 MB. Go to ESB management console, select Proxy service -> Custom Proxy -> Switch to source view. Then copy and paste below synapse configuration to create the JMS listener.

<?xml version="1.0" encoding="UTF-8"?>
<proxy xmlns="http://ws.apache.org/ns/synapse"
      name="MyDurableTopicListenerProxy"
      transports="jms"
      statistics="disable"
      trace="disable"
      startOnLoad="true">
  <target>
     <inSequence>
        <property name="OUT_ONLY" value="true"/>
        <log level="custom">
           <property name="STATE" value="dispatch message..."/>
        </log>
        <send>
           <endpoint>
              <address uri="http://localhost:9000/services/SimpleStockQuoteService"/>
           </endpoint>
        </send>
     </inSequence>
     <outSequence>
        <send/>
     </outSequence>
  </target>
  <parameter name="transport.jms.ContentType">
     <rules>
        <jmsProperty>contentType</jmsProperty>
        <default>text/xml</default>
     </rules>
  </parameter>
  <parameter name="transport.jms.ConnectionFactory">myTopicConnectionFactory</parameter>
  <parameter name="transport.jms.DestinationType">topic</parameter>
  <parameter name="transport.jms.SubscriptionDurable">true</parameter>
  <parameter name="transport.jms.Destination">MyDurbleTopic</parameter>
  <parameter name="transport.jms.DurableSubscriberName">subId-x</parameter>
  <parameter name="transport.jms.CacheLevel">consumer</parameter>
  <parameter name="transport.jms.DurableSubscriberClientID">subId-x</parameter>
  <description/>
</proxy>

You can replace whatever the WS endpoint by changing <address uri="http://localhost:9000/services/SimpleStockQuoteService"/>. Here I was used sample axis2 backend. Once you save the proxy service, it'll create durable subscription with MyDurableTopic in WSO2 MB. You don't need to create MyDurableTopic in WSO2 MB. Subscription will create a durable topic (according to JMS spec.).

Now you can send messages to durable topic and see those messages dispatch to WS endpoint. This is JMS to HTTP (cross protocol) transport. Likewise you can integrate standard pattern with this setup.

Hope this would help!

Cheers!