Creating subscriber application Part 2

Now use the messagecontext.xml file inside JetstremConf folder. Note: You can rename it as you like. We will refer it as messagecontext.xml

1. Inside the Spring4.0 boilerplate you will see these beans already present:

   • SystemPropertiesConfiguration
   • MessageServiceProperties: Defines the configuration for Message Transport services: 0. ZooKeeperTransport 0. NettyTransport
   • MessageService
   • consistenthashingaffinityscheduler

2. Inside bean "MessageServiceProperties", we add Transport services the Subscriber listens to. First read Transport Services to understand the framework.

3. Adding zookeeper.xml.

4. The transport instance named “netty” is bounded to only 1 root context “Jetstream.demo” and will listen to messages on port 15590. The other properties shall be touched upon

    <bean id="MessageServiceProperties"
        class="com.ebay.jetstream.messaging.config.MessageServiceProperties">
        <property name="nicUsage" ref="NICUsage" />
        <property name="transports">
            <list>
                <ref bean="zookeeper" />

                <bean
                    class="com.ebay.jetstream.messaging.transport.netty.config.NettyTransportConfig">
                    <property name="transportClass"
                        value="com.ebay.jetstream.messaging.transport.netty.NettyTransport" />
                    <property name="transportName" value="netty" />
                    <property name="protocol" value="tcp" />
                    <property name="contextList">
                        <list>
                            <bean
                                class="com.ebay.jetstream.messaging.transport.netty.config.NettyContextConfig">
                                <property name="contextname" value="Jetstream.demo" />
                                <property name="port" value="15590" />
                                <property name="scheduler" ref="consistenthashingaffinityscheduler"/>
                            </bean>
                        </list>
                    </property>
                    <property name="sendbuffersize" value="1048576" />
                    <property name="receivebuffersize" value="1048576" />
                    <property name="downstreamDispatchQueueSize" value="262144" />
                    <property name="connectionTimeoutInSecs" value="10" />
                    <property name="asyncConnect" value="true" />
                    <property name="numAcceptorIoProcessors" value="1" />
                    <property name="numConnectorIoProcessors" value="1" />
                    <property name="requireDNS" value="false" />
                    <property name="netmask" value="#{systemProperties['jetstream.runtime.netmask'] ?: '127.0.0.1/8'}" />
                    <property name="connectionPoolSz" value="1" />
                    <property name="maxNettyBackLog" value="20000" />
                    <property name="idleTimeoutInSecs" value="8640000"/>
                    <property name="enableCompression" value="false" />
                    <property name="tcpKeepAlive" value="true"/>
                </bean>
            </list>
        </property>
        <property name="upstreamDispatchQueueSize" value="300000" />
        <property name="upstreamDispatchThreadPoolSize" value="2" />
    </bean>

A scheduler can be optionally injected to this context binding it to a specific QOS. If scheduler is not specified, default scheduler is weighted round robin scheduler. The “MessageServiceProperties” bean is applied at run time and can be changed at runtime.

5. Every application that wires in either InboundMessagingChannel or OutboundMessagingChannel bean is required to provision MessageService bean.

    <bean id="MessageService"
        class="com.ebay.jetstream.messaging.config.MessageServiceConfiguration"
        depends-on="SystemPropertiesConfiguration">
        <property name="messageServiceProperties" ref="MessageServiceProperties" />
    </bean>

[Next: Run the application] (../wiki/Get-Set-Run)