Ushani Balasooriya's Blog: April 2013

In this post I am not going to explain about message store or message processor and their behavior. I will exactly explain how to test SOAP Fault Data in WSO2 ESB and JMS message store, a message processor with a reply sequence and a fault sequence.

Before you try out this sample, it is better to read the following articles and blog posts to get more information.

To read more on WSO ESB : http://wso2.com/products/enterprise-service-bus/
Product Documentation : http://docs.wso2.org/wiki/display/ESB460/Enterprise+Service+Bus+Documentation
Message Store : http://docs.wso2.org/wiki/display/ESB460/Message+Stores
JMS Message Stores : http://docs.wso2.org/wiki/display/ESB460/JMS+Message+Store
Message processor : http://docs.wso2.org/wiki/display/ESB460/Message+Processors
Mediators : http://docs.wso2.org/wiki/display/ESB460/Mediators
Samples on Forward Mesaging patterns with Message Stores and processors : http://docs.wso2.org/wiki/display/ESB460/Store+and+Forward+Messaging+Patterns+with+Message+Stores+and+Processors
Error Codes : http://docs.wso2.org/wiki/display/ESB460/Error+Handling+and+Error+Codes
Blogs : http://techfeast-hiranya.blogspot.com/2012/01/wso2-esb-tips-tricks-08-message-stores.html and http://maharachchi.blogspot.com/2012/09/now-you-can-send-soapfaults-to-fault.html
Behaviour : https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjbxKydMUlsUcTyFfMyUqeMps2pWqBhVnt-NP6Tn7zWYsQGOv1Wc0kl5-7Ha64B5iaqtYGXP92t1yLGFFTCJrplWNesVJCEkBgxDShrSjd84XwC6eW1HEYu6ptgMzPMFLGcC82Y2C-nisTI/s1600/dlc.png

Applications and networks can be full of errors, Applications crash. Network routers and links get into states where they cannot pass messages through with the expected efficiency. These error conditions are very likely to cause a fault or trigger a runtime exception in the ESB.

When applications and networks can be full of errors. Applications crash. Network routers and links get into states where they cannot pass messages through with the expected efficiency. These error conditions are very likely to cause a fault or trigger a runtime exception in the ESB.

It is not mandatory to associate each sequence and proxy service with a fault sequence. In situations where a fault sequence is not specified explicitly, a default fault sequence will be used to handle errors.

Whenever an error occurs in WSO2 ESB, the mediation engine attempts to provide as much information as possible on the error to the user by initializing the following properties on the erroneous message:

ERROR_CODE
ERROR_MESSAGE
ERROR_DETAIL
ERROR_EXCEPTION etc

We can configure a message broker to save the failed requests in a message store for later delivery. When the client sends requests to a proxy service , the proxy service stores the messages to a JMS message store if it cannot be delivered and then the back-end service is invoked by a message forwarding processor, which picks stored messages in the JMS message store.

To test this scenario we need the following:

Message Broker – I will be using WSO2 Message Broker (MB)
WSO2 ESB
WSO2 Application Server to invoke a service – Axis2Service (You can use any other service which will generate an exception)

To configure WSO2 ESB, AS and MB, follow the steps below:

Follow the steps in the following location. http://docs.wso2.org/wiki/display/ESB460/Configure+with+WSO2+Message+Broker
Or 1 and 2 steps in http://sandapa.blogspot.com/2013/02/jms-messaging-with-wso2-esb-460-and.html
Now the ESB and Message broker should be ready.

Configurations :
---------------------------
Set the offset as 2 in carbon.xml (<AS_HOME/repository/conf>) and start the Application server deploying the Axis2service. Refer the following document. http://docs.wso2.org/wiki/display/AS510/Installation+Guide
Create a proxy. Provide the following synapse configuration.

  <proxy name="FaultTestProxy"  
      transports="https http"  
      startOnLoad="true"  
      trace="disable">  
    <description/>  
    <target>  
      <inSequence>  
       <log level="full"/>  
       <property name="target.endpoint" value="AxisEp"/>  
       <property name="FORCE_SC_ACCEPTED" value="true" scope="axis2"/>  
       <property name="FORCE_ERROR_ON_SOAP_FAULT" value="true"/>  
       <store messageStore="Queue1"/>  
      </inSequence>  
      <outSequence>  
       <send/>  
      </outSequence>  
      <faultSequence>  
       <log level="full" category="ERROR"/>  
      </faultSequence>  
    </target>  
   </proxy>

6. Set the endpoint as following to invoke Axis2Service. This can be any service which will help to produce an error.

  <endpoint name="AxisEp">  
    <address uri="http://localhost:9765/services/Axis2Service">  
      <suspendOnFailure>  
       <errorCodes>-1</errorCodes>  
       <progressionFactor>1.0</progressionFactor>  
      </suspendOnFailure>  
    </address>  
   </endpoint>

7. Create a message store as following.

 <messageStore class="org.wso2.carbon.message.store.persistence.jms.JMSMessageStore"  
          name="Queue1">  
    <parameter name="java.naming.factory.initial">org.wso2.andes.jndi.PropertiesFileInitialContextFactory</parameter>  
    <parameter name="store.jms.cache.connection">false</parameter>  
    <parameter name="java.naming.provider.url">repository/conf/jndi.properties</parameter>  
    <parameter name="store.jms.JMSSpecVersion">1.1</parameter>  
    <parameter name="store.jms.destination">Queue1</parameter>  
   </messageStore>

8. Create a Scheduled Message Forwarding Processor as following.

 <messageProcessor class="org.apache.synapse.message.processors.forward.ScheduledMessageForwardingProcessor"  
            name="MyMsgProc"  
            messageStore="Queue1">  
    <parameter name="message.processor.reply.sequence">Axis_Ok</parameter>  
    <parameter name="max.delivery.attempts">4</parameter>  
    <parameter name="interval">5000</parameter>  
    <parameter name="message.processor.fault.sequence">Axis_Fault</parameter>  
   </messageProcessor>

9. Following fault sequence should be configured

 <sequence name="Axis_Fault">  
    <log level="custom" category="ERROR">  
      <property name="text" value="An error occured"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="ERROR_MESSAGE"  
           expression="get-property('ERROR_MESSAGE')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="ERROR_CODE"  
           expression="get-property('ERROR_CODE')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="ERROR_DETAIL"  
           expression="get-property('ERROR_DETAIL')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="ERROR_EXCEPTION"  
           expression="get-property('ERROR_EXCEPTION')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="FaultTo"  
           expression="get-property('FaultTo')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="FAULT"  
           expression="get-property('FAULT')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="SENDING_FAULT"  
           expression="get-property('SENDING_FAULT')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd" name="REPLY" expression="/"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="RESPONSE"  
           expression="get-property('RESPONSE ')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="HTTP_SC"  
           expression="get-property('HTTP_SC')"/>  
    </log>  
    <log level="full" category="ERROR"/>  
   </sequence>

The whole Synapse Configuration would be as follows :

 <?xml version="1.0" encoding="UTF-8"?>  
 <definitions xmlns="http://ws.apache.org/ns/synapse">  
   <registry provider="org.wso2.carbon.mediation.registry.WSO2Registry">  
    <parameter name="cachableDuration">15000</parameter>  
   </registry>  
 #######################  
 # Proxy  
 #######################   
   <proxy name="FaultTestProxy"  
      transports="https http"  
      startOnLoad="true"  
      trace="disable">  
    <description/>  
    <target>  
      <inSequence>  
       <log level="full"/>  
       <property name="target.endpoint" value="AxisEp"/>  
       <property name="FORCE_SC_ACCEPTED" value="true" scope="axis2"/>  
       <property name="FORCE_ERROR_ON_SOAP_FAULT" value="true"/>  
       <store messageStore="Queue1"/>  
      </inSequence>  
      <outSequence>  
       <send/>  
      </outSequence>  
      <faultSequence>  
       <log level="full" category="ERROR"/>  
      </faultSequence>  
    </target>  
   </proxy>  
 #######################  
 # Endpoint  
 #######################   
   <endpoint name="AxisEp">  
    <address uri="http://localhost:9765/services/Axis2Service">  
      <suspendOnFailure>  
       <errorCodes>-1</errorCodes>  
       <progressionFactor>1.0</progressionFactor>  
      </suspendOnFailure>  
    </address>  
   </endpoint>  
 #######################  
 # Fault Sequence  
 #######################   
   <sequence name="Axis_Fault">  
    <log level="custom" category="ERROR">  
      <property name="text" value="An error occured"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="ERROR_MESSAGE"  
           expression="get-property('ERROR_MESSAGE')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="ERROR_CODE"  
           expression="get-property('ERROR_CODE')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="ERROR_DETAIL"  
           expression="get-property('ERROR_DETAIL')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="ERROR_EXCEPTION"  
           expression="get-property('ERROR_EXCEPTION')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="FaultTo"  
           expression="get-property('FaultTo')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="FAULT"  
           expression="get-property('FAULT')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="SENDING_FAULT"  
           expression="get-property('SENDING_FAULT')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd" name="REPLY" expression="/"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="RESPONSE"  
           expression="get-property('RESPONSE ')"/>  
      <property xmlns:ns="http://org.apache.synapse/xsd"  
           name="HTTP_SC"  
           expression="get-property('HTTP_SC')"/>  
    </log>  
    <log level="full" category="ERROR"/>  
   </sequence>  
    <sequence name="main">  
    <in>  
      <log level="full"/>  
      <filter source="get-property('To')" regex="http://localhost:9000.*">  
       <send/>  
      </filter>  
    </in>  
    <out>  
      <send/>  
    </out>  
    <description>The main sequence for the message mediation</description>  
   </sequence>  
 #######################  
 # Message Store  
 #######################   
   <messageStore class="org.wso2.carbon.message.store.persistence.jms.JMSMessageStore"  
          name="Queue1">  
    <parameter name="java.naming.factory.initial">org.wso2.andes.jndi.PropertiesFileInitialContextFactory</parameter>  
    <parameter name="store.jms.cache.connection">false</parameter>  
    <parameter name="java.naming.provider.url">repository/conf/jndi.properties</parameter>  
    <parameter name="store.jms.JMSSpecVersion">1.1</parameter>  
    <parameter name="store.jms.destination">Queue1</parameter>  
   </messageStore>  
 #######################  
 # Message Processor  
 #######################   
   <messageProcessor class="org.apache.synapse.message.processors.forward.ScheduledMessageForwardingProcessor"  
            name="MyMsgProc"  
            messageStore="Queue1">  
    <parameter name="message.processor.reply.sequence">Axis_Ok</parameter>  
    <parameter name="max.delivery.attempts">4</parameter>  
    <parameter name="interval">5000</parameter>  
    <parameter name="message.processor.fault.sequence">Axis_Fault</parameter>  
   </messageProcessor>  
 </definitions>

To Test:
------------

1. Via SOAP create a new SOAP project and provide the following wsdl URL,
http://localhost:8281/services/FaultTestProxy?wsdl

2. Then stop the Axis2Service and send the following request in echoInt method. (We are sending a String value except an int value)

 <soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ser="http://service.carbon.wso2.org">  
   <soapenv:Header/>  
   <soapenv:Body>  
    <ser:echoInt>  
      <!--Optional:-->  
      <ser:x>String</ser:x>  
    </ser:echoInt>  
   </soapenv:Body>  
 </soapenv:Envelope>

3. Then the message store will store the message. Then start the Axis2Service. Then the Message Processor will pick the message and try to forward it. Due to the string value, following Error codes will be printed in the ESB Server console.

ERROR - LogMediator text = An error occured, ERROR_MESSAGE = Invalid value "String" for element x, ERROR_CODE = Client, ERROR_DETAIL = , ERROR_EXCEPTION = , FaultTo = , FAULT = TRUE, SENDING_FAULT = null, REPLY = <?xml version='1.0' encoding='utf-8'?><soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"><soapenv:Header><ns:BAMEvent xmlns:ns="http://wso2.org/ns/2010/10/bam" activityID="13320046414250_138"/></soapenv:Header><soapenv:Body><soapenv:Fault xmlns:axis2ns26="http://schemas.xmlsoap.org/soap/envelope/"><faultcode>axis2ns26:Client</faultcode><faultstring>Invalid value "String" for element x</faultstring><detail/></soapenv:Fault></soapenv:Body></soapenv:Envelope>, RESPONSE = null, HTTP_SC = 500

This was done with the great help provided by Charitha Kankanamge. :)

Ushani Balasooriya's Blog

Wednesday, April 24, 2013

How to test SOAP Fault Data in WSO2 ESB and JMS message store, a message processor with a reply sequence and a fault sequence

About Me

Labels