JDBC Message Store

Sample scenario

In this sample:

• The client sends requests to a proxy service.
• The proxy service stores the messages in a JDBC message store. 
• The back-end service is invoked by a message forwarding processor, which picks the messages stored in the JDBC message store. 

Prerequisites:

1. Setup the database.

   • If you are setting up a MySQL database, the DB script to create the required table is as follows:

     CREATE TABLE jdbc_message_store(
     indexId BIGINT( 20 ) NOT NULL AUTO_INCREMENT ,
     msg_id VARCHAR( 200 ) NOT NULL ,
     message BLOB NOT NULL ,
     PRIMARY KEY ( indexId )
     )

   • If you are setting up a H2 database, the DB script to create the required table is as follows:

     CREATE TABLE jdbc_message_store(
     indexId BIGINT( 20 ) NOT NULL AUTO_INCREMENT ,
     msg_id VARCHAR( 200 ) NOT NULL ,
     message BLOB NOT NULL ,
     PRIMARY KEY ( indexId )
     )

     Note

     You can create a similar script based on the database you want to set up.

2. Add the relevant database driver into the repository/components/lib folder.

Configure the sample

1. Create a proxy service that stores messages to the JDBC message store.
2. Create a JDBC message store.

3. Create a message forwarding processor to consumes the messages stored in the message store.

   Sample configuration that uses a MySQL database named sampleDB and the database table jdbc_message_store

   <proxy xmlns="http://ws.apache.org/ns/synapse"
         name="MessageStoreProxy"
         transports="https http"
         startOnLoad="true"
         trace="disable">
     <description/>
     <target>
        <inSequence>
           <property name="FORCE_SC_ACCEPTED" value="true" scope="axis2"/>
           <property name="OUT_ONLY" value="true"/>
           <property name="target.endpoint" value="StockQuoteServiceEp"/>
           <store messageStore="SampleStore"/>
        </inSequence>
     </target>
     <publishWSDL uri="http://localhost:9000/services/SimpleStockQuoteService?wsdl"/>
   </proxy>
    
   <messageStore xmlns="http://ws.apache.org/ns/synapse"
                class="org.apache.synapse.message.store.impl.jdbc.JDBCMessageStore"
                name="SampleStore">
     <parameter name="store.jdbc.password"/>
     <parameter name="store.jdbc.username">root</parameter>
     <parameter name="store.jdbc.driver">com.mysql.jdbc.Driver</parameter>
     <parameter name="store.jdbc.table">jdbc_message_store</parameter>
     <parameter name="store.jdbc.connection.url">jdbc:mysql://localhost:3306/sampleDB</parameter>
   </messageStore>
    
   <messageProcessor xmlns="http://ws.apache.org/ns/synapse"
                    class="org.apache.synapse.message.processor.impl.forwarder.ScheduledMessageForwardingProcessor"
                    name="ScheduledProcessor"
                    messageStore="SampleStore">
     <parameter name="max.delivery.attempts">5</parameter>
     <parameter name="interval">10</parameter>
     <parameter name="is.active">true</parameter>
   </messageProcessor>

Configure the back-end service

1. Deploy the SimpleStockQuoteService client by navigating to <EI_HOME>/samples/axis2Server/src/SimpleStockQuoteService, and running the ant command in the command prompt or shell script. This will build the sample and deploy the service for you. For more information on sample back-end services, see Deploying sample back-end services.
2. WSO2 EI comes with a default Axis2 server, which you can use as the back-end service for this sample. To start the Axis2 server, navigate to <EI_HOME>/samples/axis2server, and run axis2Server.sh on Linux or axis2Server.bat on Windows.
3. Go to http://localhost:9000/services/SimpleStockQuoteService?wsdl and verify that the service is running.

Execute the sample

To invoke the proxy service, navigate to <EI_HOME>/repository/samples/axis2client, and execute the following command: 

ant stockquote -Daddurl=http://localhost:8280/services/MessageStoreProxy