Setting up a restlet with Camel in JBoss Fuse

If you have already successfully gone through the steps of the previous tutorial, this is going to be quite fast and straightforward. All you need to know is that in Camel you can set up a restlet to listen to a specific URL/port with the “restlet” prefix.

Let’s assume that we want to listen for REST request and turn the body of the request into a message to be queued on one of our (already existent) ActiveMQ. As in the previous example, we can accomplish the task without even write a line of Java code.

We can add the following elements to our blueprint.xml file:

    <route>
        <from uri="restlet:http://localhost:8282/demo-endpoint?restletMethod=POST"></from>
        <camel:setBody>
            <simple>test=true</simple>
        </camel:setBody>
        <log message="The request body is: ${body}"></log>
        <to uri="activemq:sink-queue" pattern="InOnly"></to>
        <to uri="mock:result"></to>
    </route>

Here I’m specifying the restletMethod parameter, which tells Camel to only respond to GET HTTP request (i.e. any other HTTP verb will result in the request to be discarded). The setBody element is used for making thigs simpler: it sets the body of the exchange to the child value, as you might expect. Now we can “clean-install” the project as usual and switch to the Karaf console. Update the package with a osgi:update command (here, 251 is the ID of my bundle, you will probably have a different one. You can find out what ID your bundle has by executing a “list” command):

JBossFuse:karaf@root> osgi:update 251

After this, execute “list” and take a look at the output. In correspondence with the updated bundle you should see something like this:

[ 251] [Active     ] [GracePeriod ] [       ] [   60] A Camel Blueprint Route (1.0.0)

This is because the bundle has a missing dependency: the camel-restlet Feature. The bundle has been successfully installed, but it cannot be started until the missing dependency is satisfied. The missing feature is not installed by default in Fuse. Luckily, you can easily get it by typing the following command:

JBossFuse:karaf@root> features:install camel-restlet

To learn more about Features, refer to the official documentation.

Restart your bundle. The restlet is now ready. You can try and call it with whatever method you prefer. For simplicity, i present you the command used to perform a test with curl:

curl --data "test=true" http://localhost:8282/demo-endpoint

 

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