Creating a blocking transport sender/receiver

Hi J

I believe what you want is

Apache < -(AJP) -> ESB (on tomcat as web app) < -(https/http) -> External

One solution is to proxy the request to the ESB. It is what you have done and it was slow when using https.

For other solution (I haven’t try this and just a suggestion), you have to do some code (not much).

You want a blocking sender/receiver but in ESB we used non blocking one. On the other hand, we are not encouraging to use admin console transport. Therefore, you have to do little bit code.

First, I believe you are using ESB as a web application in tomcat container.

In axis2, you can’t specify two http/https pair with same name (In axis2.xml). Therefore, let’s take our transport name as “blockhttp”. Then you have to register it in axis2.xml.

You have to add another HTTP connector to tomcat (port 8085)

<transportReceiver name="blockhttp”

                       class="org.apache.axis2.transport.http.SimpleHTTPServer">

        <parameter name="port">8085</parameter 

  </transportReceiver>

<transportSender name="blockhttp"

                     class="org.apache.axis2.transport.http.CommonsHTTPTransportSender">

        <parameter name="PROTOCOL">HTTP/1.1</parameter>

        <parameter name="Transfer-Encoding">chunked</parameter>    </transportSender>

(You can refer to axis2.xml from axis2 distribution)

First you have to write a Servlet that extends AxisServlet. Take a look at SynapseAxisServlet or ESBServlet. You have to override one method as follows. Take SynapseAxisServlet and copy to another file and edit it.

protected MessageContext createMessageContext(HttpServletRequest req, HttpServletResponse resp) throws IOException {

        MessageContext msgContext = super.createMessageContext(req, resp);

        TransportInDescription adminTransIn = axisConfiguration.getTransportIn("blockhttp");

        if (adminTransIn != null) {

            msgContext.setTransportIn(adminTransIn);

            msgContext.getOptions().setTransportIn(adminTransIn);

        }

        TransportOutDescription adminTransportOutDescription =

                axisConfiguration.getTransportOut("blockhttp");

        if (adminTransportOutDescription != null) {

            msgContext.setTransportOut(adminTransportOutDescription);

            msgContext.getOptions().setTransportOut(adminTransportOutDescription);

        }

        return msgContext;

    }

Then you have to move to the synapse code based

MessageHelper.java

Checks the method

public static org.apache.axis2.context.MessageContext clonePartially(

        org.apache.axis2.context.MessageContext ori) throws AxisFault {

…..

}

And add following lines to it (append)

 newMC.getOptions().setTransportOut(ori.getTransportOut());

 newMC.getOptions().setTransportIn(ori.getTransportIn());

Now take the web.xml of ESB and add servlet and servlet mapping

  <servlet>

        <servlet-name>BlockServlet</servlet-name>

        <servlet-class>org.my.blocking.BlockServlet </servlet-class>

    </servlet>

<servlet-mapping>

        <servlet-name> BlockServlet </servlet-name>

        <url-pattern>/blockhttp/*</url-pattern>

    </servlet-mapping>

Now any request with context as >/blockhttp/* should go to the servlet you have written.

Now if you run esb with default configuration and if the sample server is setup and if you invoke esb as

Ant stockquote -Daddurl=http://localhost:9000/soap/SimpleStockQuoteService -Dtrpurl=https://localhost:9444/esb/blockhttp

It should work (now ESb is on https://localhost:9444/esb/blockhttp)

But if you are trying a sample which has an explicitly specified endpoint with URI, then, you have to change some code in the synapse to work this. This is because , axis2 pick transport based on the protocol and name of the transport definition in axis2.xml.Therefore,if the address of the endpoint is http://yyyy/yy/ then , always pick the transport definition with name ‘http’ from axis2.xml.

(take a look at ClientUtils.java from axs2 code base , it show how transport in and out resolved )

To fix , this let’s introduce an attribute to endpoint ‘use’ and if this attribute is present , take the corresponding transport using value of this attribute. You have to add code to process this attribute (DefaultEndpointFactory) …Two or three line code. (If you want it serialize, then you also have to change DefaultEndpointSerializer ).

Then look at Axis2FlexibleMEPClient and after MessageContext axisOutMsgCtx = cloneForSend(originalInMsgCtx); or inside it’s logic.

Take value of the attribute ‘use’ and if it is available get TransportIn and TransportOut using

 newMC.getOptions().setTransportOut(axisConfiguration.getTransportOut(“value of ‘use’ attribute”));

 newMC.getOptions().setTransportIn(axisConfiguration.getTransportIn(“value of ‘use’ attribute”);

You may now not need the suggested code change in the MessageHelper.java.

The above logic has to carefully be changed.

I believe, If you are enable AJP connector in the tomcat and use its port as ‘blockhttp” port, then, you may can directly connect apache and ESB (tomcat war). But, I don’t know, I haven’t use AJP or even try out.

Really, I am busy; otherwise, I could have able to help you by doing these changes myself and getting it work.

Thanks

Indika