incode-camel-example-webapp

This is an example webapp which bootstraps Camel to consume events published via PublishMq service to an ActiveMQ event bus.

The webapp sets up an ActiveMQ queue accessible via tcp://localhost:61616, and sets up a Camel route to consume from that.

Within the Camel route it defines a single HelloWorldProcessor that will just print to stdout (of the webapp) for any InteractionDto objects that are published.

It also defines a simple E2E test to play the role of an Apache Isis app, configured to use the PublishMQ publisher service.

Build

Build using:

mvn clean install

Camel webapp

Run using:

mvn jetty:run

This sets up the HelloWorldProcessor:

public class HelloWorldProcessor extends ProcessorAbstract {

    @Override
    public void process(final Exchange exchange) throws Exception {
        final InteractionDto interactionDto = MessageUtil.interactionFrom(exchange.getIn());

        System.out.println(toXml(interactionDto));
    }
}

in a camel route:

<camelContext xmlns="http://camel.apache.org/schema/spring">

    <route id="inToOutRoute" errorHandlerRef="myDeadLetterErrorHandler">
        <from uri="activemq-broker:queue:memberInteractionsQueue"/>
        <unmarshal>
            <jaxb contextPath="org.apache.isis.schema.ixn.v1" prettyPrint="true"/>
        </unmarshal>

        <camel:process ref="addExchangeHeaders"/>
        <camel:process ref="helloWorld"/>

        <camel:to uri="stream:out"/>
    </route>
    ...
</camelContext>

Note that there is no UI. However its configuration will have opened up an ActiveMq queue accessible over tcp://localhost:61616.

Test

Run the E2e_Test class, eg using your IDE. This plays the role of an Apache Isis app:

public class E2e_Test {

    PublisherServiceUsingActiveMq service;

    @Before
    public void setUp() throws Exception {

        assumeThat(System.getProperty("e2e"), is(notNullValue()));

        service = new PublisherServiceUsingActiveMq();
        final HashMap<String, String> props = Maps.newHashMap();

        props.put(PublisherServiceUsingActiveMq.KEY_VM_TRANSPORT_URL, "tcp://localhost:61616");
        service.init(props);
    }

    @Test
    public void publish() throws Exception {

        final URL resource = Resources.getResource(getClass(), "InteractionDto.xml");
        final String s = Resources.toString(resource, Charsets.UTF_8);
        final InteractionDto dto = JaxbUtil.fromXml(new StringReader(s), InteractionDto.class);

        service.republish(dto);
    }
}

Note	Configure the "e2e" system property using -De2e, otherwise the test is a no-op.

Monitor

hawt.io is a standalone webapp that acts as a client to monitor other applications. It has built in support for both ActiveMQ and Camel. The Camel webapp provides access to hawt.io because it is configured to also start the Jolokia gateway servlet.

Download hawt.io from here and start using:

java -jar hawtio-app-2.0.2.jar --port 7070

Open up a browser at http://localhost:7070/hawtio/

Connect to running camel-webapp instance by registering a connection to http://localhost:8080//api/jolokia.