Thursday, October 15, 2015

Getting Started with Simple wso2 ESB EJB Mediator Sample


The EJB mediator calls an external Enterprise JavaBean(EJB) and stores the result in the message payload or in a message context property. Currently, this mediator supports EJB3 Stateless Session Beans and Stateful Session Beans.

Before Start first look what is EJB Mediator and what is EJB now Let's see how to Run a Simple Hello Name using EJB Mediator. in order to run the the sample we need to configure our Environment So the Requirements are
In the context of EJB the the implementation is focused on statefull and stateless session beans, so later when dicussing the sample scenarios and will dig in to the details on how to configure those with the WSO2 Ejb mediator
So let us now focus now on configuring EJB service invocation with WSO2 ESB.

Configure the ESB

  • Please download Jboss 7(jboss-as-7.1.1.Final Latest)  we do have test this with different application servers but for this demonstration we will be using Jboss 7 there you need to  copy jboss-client.jar to ESB_HOME/repository/components/lib
  • Please find the HelloName.jar (Ejb service) you will be find the HelloName  jar attached with this article (will discuss what this demo service and its implementation separately) please copy the HelloName.jar file to  JBOSS_HOME/standalone/deployments/  and  ESB_HOME/repository/components/lib
  • As next step you may have to configure AS connection properties and the you will be able define them in  synapse.properties (ESB_HOME/repository/conf ) it has following properties which is required to communicate with the AS,depending on the application server which you may use the configuration parameteres might get change, the following is required when you need to connect EJB services hosted in Jboss AS 7
  • Start ESB and Jboss AS

Configure Ejb Mediator for stateless bean

Idea of this demo such as when requests closest location he has to pass the name and  in this scenario when the requests comes first we need to invoke the sayHello method which is exposed as EJB service, and to invoke the method it requires to check HelloWorld so it we picking the name and pass it to ejb Container and the return result will be assign to the synapse property context  and using enrich mediator we can transform the incoming request as requires by the source, let see how this can be configured in ESB level

ejb Proxy

<?xml version="1.0" encoding="UTF-8"?>
<proxy xmlns="http://ws.apache.org/ns/synapse"
       name="ejb"
       transports="https,http"
       statistics="disable"
       trace="disable"
       startOnLoad="true">
   <target>
      <inSequence>
         <property name="response" value="init" scope="default" type="STRING"/>
         <log level="custom">
            <property name="response" value="{//name}"/>
         </log>
         <ejb beanstalk="jack"
              class="org.NewBeanRemote"
              method="sayHello"
              target="response"
              jndiName="ejb:/EJBModule3/NewBean!org.NewBeanRemote">
            <args>
               <arg xmlns:m="http://org" value="{//m:name}"/>
            </args>
         </ejb>
         <payloadFactory media-type="xml">
            <format>
               <ejb xmlns="">
                  <response>$ctx.response</response>
               </ejb>
            </format>
            <args/>
         </payloadFactory>
         <respond/>
      </inSequence>
   </target>
   <description/>
</proxy>

in above proxy we need to set beanstalk , class, method, target and  jndiName we already looked about these parameters in previous post about EJB Mediator. here my beanstalk id is jack bu we can set unique id for that the important thing is we are going to use this name in synapse properties to set the property values. my class name is org.NewBeanRemote and method name is sayHello . the value which my method returning is naming as response in target finally we can catch the jndi name from JBoss server console.

synapse property

synapse.beanstalks=jack
synapse.beanstalks.jack.java.naming.factory.url.pkgs=org.jboss.ejb.client.naming
synapse.beanstalks.jack.cache.warn.limit.stateless=5
synapse.beanstalks.jack.cache.warn.limit.stateful=5
synapse.beanstalks.jack.cache.timeout.stateless=1
synapse.beanstalks.jack.cache.timeout.stateful=1
after  set the synapse properties value we will sent the below request to the proxy which we create as ejb.

Soap Request

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
  <soapenv:Body>
    <sayHello xmlns="http://org">
<name>rajjaz</name>
    </sayHello>
  </soapenv:Body>
</soapenv:Envelope>  

 if everything success you will get bellow response to your soap Request

Soap Response

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
   <soapenv:Body>
      <ejb>
         <response>Hello rajjaz</response>
      </ejb>
   </soapenv:Body>
</soapenv:Envelope>

Debug Log


[2015-10-09 10:39:09,699] DEBUG - wire >> "POST /services/ejb.ejbHttpSoap11Endpoint HTTP/1.1[\r][\n]"
[2015-10-09 10:39:09,700] DEBUG - wire >> "Accept-Encoding: gzip,deflate[\r][\n]"
[2015-10-09 10:39:09,700] DEBUG - wire >> "Content-Type: text/xml;charset=UTF-8[\r][\n]"
[2015-10-09 10:39:09,700] DEBUG - wire >> "SOAPAction: "urn:mediate"[\r][\n]"
[2015-10-09 10:39:09,701] DEBUG - wire >> "Content-Length: 201[\r][\n]"
[2015-10-09 10:39:09,701] DEBUG - wire >> "Host: rajjaz-ThinkPad-T540p:8280[\r][\n]"
[2015-10-09 10:39:09,701] DEBUG - wire >> "Connection: Keep-Alive[\r][\n]"
[2015-10-09 10:39:09,702] DEBUG - wire >> "User-Agent: Apache-HttpClient/4.1.1 (java 1.5)[\r][\n]"
[2015-10-09 10:39:09,702] DEBUG - wire >> "[\r][\n]"
[2015-10-09 10:39:09,702] DEBUG - wire >> "<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">[\n]"
[2015-10-09 10:39:09,702] DEBUG - wire >> "  <soapenv:Body>[\n]"
[2015-10-09 10:39:09,702] DEBUG - wire >> "    <sayHello xmlns="http://org">[\n]"
[2015-10-09 10:39:09,702] DEBUG - wire >> "<name>rajjaz</name>[\n]"
[2015-10-09 10:39:09,702] DEBUG - wire >> "    </sayHello>[\n]"
[2015-10-09 10:39:09,702] DEBUG - wire >> "  </soapenv:Body>[\n]"
[2015-10-09 10:39:09,703] DEBUG - wire >> "</soapenv:Envelope>"
[2015-10-09 10:39:09,707] DEBUG - ProxyServiceMessageReceiver Proxy Service ejb received a new message from : 127.0.0.1
[2015-10-09 10:39:09,708] DEBUG - ProxyServiceMessageReceiver Message To: /services/ejb.ejbHttpSoap11Endpoint
[2015-10-09 10:39:09,708] DEBUG - ProxyServiceMessageReceiver SOAPAction: urn:mediate
[2015-10-09 10:39:09,708] DEBUG - ProxyServiceMessageReceiver WSA-Action: urn:mediate
[2015-10-09 10:39:09,708] DEBUG - ProxyService Setting default fault-sequence for proxy
[2015-10-09 10:39:09,708] DEBUG - ProxyServiceMessageReceiver Using the anonymous in-sequence of the proxy service for mediation
[2015-10-09 10:39:09,708] DEBUG - SequenceMediator Start : Sequence <anonymous>
[2015-10-09 10:39:09,708] DEBUG - SequenceMediator Sequence <SequenceMediator> :: mediate()
[2015-10-09 10:39:09,708] DEBUG - SequenceMediator Mediation started from mediator position : 0
[2015-10-09 10:39:09,708] DEBUG - SequenceMediator Building message. Sequence <SequenceMediator> is content aware
[2015-10-09 10:39:09,709] DEBUG - PropertyMediator Start : Property mediator
[2015-10-09 10:39:09,709] DEBUG - PropertyMediator Setting property : response at scope : default to : init (i.e. constant : init)
[2015-10-09 10:39:09,709] DEBUG - PropertyMediator End : Property mediator
[2015-10-09 10:39:09,709] DEBUG - LogMediator Start : Log mediator
[2015-10-09 10:39:09,709]  INFO - LogMediator response = {//name}
[2015-10-09 10:39:09,710] DEBUG - LogMediator End : Log mediator
[2015-10-09 10:39:09,933] DEBUG - PayloadFactoryMediator #mediate. Transformed payload format>>> <pfPadding><ejb><response>Hello rajjaz</response></ejb></pfPadding>
[2015-10-09 10:39:09,933] DEBUG - RespondMediator Start : Respond Mediator
[2015-10-09 10:39:09,940] DEBUG - RespondMediator End : Respond Mediator
[2015-10-09 10:39:09,940] DEBUG - SequenceMediator End : Sequence <anonymous>
[2015-10-09 10:39:09,941] DEBUG - wire << "HTTP/1.1 200 OK[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "Host: rajjaz-ThinkPad-T540p:8280[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "SOAPAction: "urn:mediate"[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "Accept-Encoding: gzip,deflate[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "Content-Type: text/xml;charset=UTF-8; charset=UTF-8[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "Date: Fri, 09 Oct 2015 05:09:09 GMT[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "Transfer-Encoding: chunked[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "Connection: Keep-Alive[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "ce[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "<?xml version='1.0' encoding='UTF-8'?><soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"><soapenv:Body><ejb><response>Hello rajjaz</response></ejb></soapenv:Body></soapenv:Envelope>[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "0[\r][\n]"
[2015-10-09 10:39:09,941] DEBUG - wire << "[\r][\n]"

References