Sample 11: Using a Full Registry-Based Configuration and Sharing a Configuration Between Multiple Instances

Note that WSO2 EI is shipped with the following changes to what is mentioned in this documentation:

<PRODUCT_HOME>/repository/samples/ directory that includes all Integration profile samples is changed to <EI_HOME>/samples/service-bus/.
<PRODUCT_HOME>/repository/samples/resources/ directory that includes all artifacts related to the Integration profile samples is changed to <EI_HOME>/samples/service-bus/resources/.

Introduction

This sample demonstrates the use of a full registry-based ESB configuration, to start a remote configuration from multiple ESB instances in a clustered environment. Here the Synapse configuration of a given node hosting the ESB simply points to the registry and looks up the actual configuration by requesting the key synapse.xml.

Full registry-based configuration is not dynamic at the moment; it is not reloading itself.

Prerequisites

For a list of prerequisites, see Prerequisites to Start the ESB Samples.

Building the sample

The XML configuration for this sample is as follows:

<definitions xmlns="http://ws.apache.org/ns/synapse">
    <registry provider="org.wso2.carbon.mediation.registry.ESBRegistry">
        <parameter name="root">file:./repository/samples/resources/</parameter>
        <parameter name="cachableDuration">15000</parameter>
    </registry>
</definitions>

This configuration file synapse_sample_11.xml is available in the <ESB_HOME>/repository/samples directory.

To build the sample

Start the ESB with the sample 11 configuration. For instructions on starting a sample ESB configuration, see Starting the ESB with a sample configuration.

The operation log keeps running until the server starts, which usually takes several seconds. Wait until the server has fully booted up and displays a message similar to "WSO2 Carbon started in n seconds."
Start the Axis2 server. For instructions on starting the Axis2 server, see Starting the Axis2 server.
Deploy the back-end service SimpleStockQuoteService. For instructions on deploying sample back-end services, see Deploying sample back-end services.
Now you have a running ESB instance and a back-end service deployed. In the next section, we will send a message to the back-end service through the ESB using a sample client.

Executing the sample

The sample client used here is the Stock Quote Client, which can operate in several modes. For further details on this sample client and its operation modes, see Stock Quote Client.

To execute the sample client

Run the following command from the <ESB_HOME>/samples/axis2Client directory.

ant stockquote -Daddurl=http://localhost:9000/services/SimpleStockQuoteService -Dtrpurl=http://localhost:8280/

Analyzing the output

When you analyze the debug log output on the ESB console once the client is executed, you will see the following:

[HttpServerWorker-1] INFO LogMediator - message = This is a dynamic ESB configuration

The actual synapse.xml that is loaded when the sample is run is:

<!-- a registry based Synapse configuration -->
<definitions xmlns="http://ws.apache.org/ns/synapse">
    <sequence name="main">
        <log level="custom">
            <property name="message" value="This is a dynamic ESB configuration"/>
        </log>
        <send/>
    </sequence>
</definitions>