This projects contains a set of OSGi bundles that bootstrap the use of ServiceMix 4. It is intended as a starting point for the creation of additional bundles, and as a guide to using SMX feaures.

The Ping Pong bootstrap is used to show inter-bundle request-response communication using ActiveMQ.

1. A Pinger defines a Camel route which periodically triggers a message to be sent and prints out the response.
2. A Ponger listens for ping messages on a known queue, and responds by invoking an OSGi Blueprint service defined in an implementation bundle to generate the response.

Project layout

The Maven projects contained within are as follows:

• smxb-features - Contains an XML features file used to install the rest of the bundles.
• smxb-pinger - Contains a bundle that periodically sends a ping message over the embedded ActiveMQ instance. Also exposes a RESTful web service on port 9090 that allows you you ping the service manually.
• smxb-ponger - Listens on the queue and replies after invoking an OSGi Blueprint service to generate a response. Contains an additional NMR-based route as an alternative mechanism for chatting with the pinger in the same ServiceMix instance.
• smxb-ponger-service - Contains the implementation of that service.

There is also an additional parent project camel-bundle that simplifies the Maven project configuration.

Prerequisites

Set up ServiceMix by downloading the latest 4.4.1+ version from FuseSource. The installation guide can be reached from the Documentation tab on that page.

Ensure that Maven is set up on your system.

Installation

Download this project and run

smx-bootstraps> mvn clean install

Start up ServiceMix

$SERVICEMIX_HOME> bin/servicemix console 

 ____                  _          __  __ _      
/ ___|  ___ _ ____   _(_) ___ ___|  \/  (_)_  __
\___ \ / _ \ '__\ \ / / |/ __/ _ \ |\/| | \ \/ /
 ___) |  __/ |   \ V /| | (_|  __/ |  | | |>  < 
|____/ \___|_|    \_/ |_|\___\___|_|  |_|_/_/\_\

  Apache ServiceMix (4.4.1-fuse-01-06)

Hit '<tab>' for a list of available commands
and '[cmd] --help' for help on a specific command.

You may need to wait for a while as Servicemix downloads and starts the bundles it needs to run fully. Running the list command should show around 200+ bundles all Active.

karaf@root> list
...
[ 220] [Active     ] [            ] [       ] [   50] camel-jetty (2.8.0.fuse-01-06)
karaf@root> _

If camel-jetty does not appear in the bundle list, install it; it is required to enable the Pinger web service:

karaf@root> features:install camel-jetty

Install the smxb-features features file. This gets pulled out from your local Maven repository, and defines which bundles you mean to install for the bootstrap project.

karaf@root> features:addurl mvn:com.fusesource.examples/smxb-features/1.0-SNAPSHOT/xml/features

You can now check that the features defined in that file are available for installation:

karaf@root> features:list | grep smxb
[uninstalled] [1.0                 ] smxb-ping-pong                       smxb-features-1.0-SNAPSHOT       
[uninstalled] [1.0                 ] smxb-ping                            smxb-features-1.0-SNAPSHOT       
[uninstalled] [1.0                 ] smxb-pong                            smxb-features-1.0-SNAPSHOT

NP: It's often a good idea to prefix all of your features and bundles with a known string, such as smxb in this case, so you can easily find them via the grep command in the various listings.

Install all of the necessary OSGi bundles by installing the smxb-ping-pong feature

karaf@root> features:install smxb-ping-pong
karaf@root> list | grep smxb
[ 236] [Active     ] [Created     ] [       ] [   60] smxb-pinger (1.0.0.SNAPSHOT)
[ 237] [Active     ] [Created     ] [       ] [   60] smxb-ponger (1.0.0.SNAPSHOT)
[ 238] [Active     ] [Created     ] [       ] [   60] smxb-ponger-service (1.0.0.SNAPSHOT)

You can then start the bundles (the numbers may vary in your installation)

karaf@root> start 236
karaf@root> start 237
karaf@root> start 238

The log should now contain output from your bundles

karaf@root> log:display -n 5
13:03:11,760 | INFO  | msConsumer[pings | pong                             | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Received ping: Ping at 2011-12-30 13:03:11
13:03:11,772 | INFO  | tenerContainer-1 | toActiveMQ                       | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Received AMQ: [Pong from service to [Ping at 2011-12-30 13:03:11]]
13:03:16,752 | INFO  | foo              | pingOnTimer                      | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Timer generated Ping at 2011-12-30 13:03:16
13:03:16,759 | INFO  | msConsumer[pings | pong                             | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Received ping: Ping at 2011-12-30 13:03:16
13:03:16,768 | INFO  | tenerContainer-1 | toActiveMQ                       | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Received AMQ: [Pong from service to [Ping at 2011-12-30 13:03:16]]

Check that the web service is running by hitting the following from your web browser:

http://localhost:9090/ping?msg=Ping!!!

Congratulations. You have just deployed and run a bootstrapped integration project!

Next steps

Working with bundles

Change the Camel route defined in smxb-pinger/target/classes/OSGI-INF/blueprint/blueprint.xml. Run

smx-bootstraps> mvn clean install

In ServiceMix, update the smxb-pinger bundle

karaf@root> list | grep smxb-pinger
[ 236] [Active     ] [Created     ] [       ] [   60] smxb-pinger (1.0.0.SNAPSHOT)
karaf@root> update 236

Your changes should now be visible.

Configuration

The smxb-pinger and smxb-ponger projects make use of OSGi Blueprints config services. From the same blueprints.xml:

<cm:property-placeholder persistent-id="com.fusesource.examples.pinger"
	update-strategy="reload">
	<cm:default-properties>
		<cm:property name="broker.url" value="failover:(tcp://127.0.0.1:61616)" />
	</cm:default-properties>
</cm:property-placeholder>
...
<bean id="activemq" class="org.apache.activemq.camel.component.ActiveMQComponent">
    <property name="brokerURL" value="${broker.url}" />
</bean>

You can dynamically change the default configuration by creating a properties file in the $SERVICEMIX_HOME/etc directory called {persistent-id}.cfg, so in this case com.fusesource.examples.pinger.cfg. This is a standard properties file, within which you can override any of the properties used in your blueprints.xml.

Adding the following line to the file and saving it will stop the bundles that listen on that persistent-id and start them again.

broker.url=failover:(tcp://127.0.0.1:61616,tcp://127.0.0.1:61617)

This assumes that the cm:property-placheholders are configured with update-strategy="reload", if not the bundles need to be stopped and started manually.

The log should show the affected Camel routes stopping and starting:

13:24:58,181 | INFO  | Thread-51        | BlueprintCamelContext            | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Apache Camel 2.8.0-fuse-01-06 (CamelContext:smxb-pinger) is shutting down
13:24:58,182 | INFO  | Thread-51        | DefaultShutdownStrategy          | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Starting to graceful shutdown 2 routes (timeout 300 seconds)
13:24:58,183 | INFO  | 8 - ShutdownTask | DefaultShutdownStrategy          | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Route: pingOnTimer shutdown complete, was consuming from: Endpoint[timer://foo?period=5000]
13:24:58,183 | INFO  | 8 - ShutdownTask | DefaultShutdownStrategy          | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Route: toActiveMQ shutdown complete, was consuming from: Endpoint[direct://toActiveMQ]
13:24:58,183 | INFO  | Thread-51        | DefaultShutdownStrategy          | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Graceful shutdown of 2 routes completed in 0 seconds
13:24:58,185 | INFO  | Thread-51        | TemporaryQueueReplyManager       | ?                                   ? | 93 - org.apache.camel.camel-jms - 2.8.0.fuse-01-06 | Stopping reply listener container on endpoint: Endpoint[activemq://pings]
13:24:58,973 | INFO  | Thread-51        | DefaultInflightRepository        | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Shutting down with no inflight exchanges.
13:24:58,974 | INFO  | Thread-51        | BlueprintCamelContext            | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Uptime: 39.091 seconds
13:24:58,974 | INFO  | Thread-51        | BlueprintCamelContext            | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Apache Camel 2.8.0-fuse-01-06 (CamelContext: smxb-pinger) is shutdown in 0.793 seconds
13:24:58,990 | INFO  | rint Extender: 3 | BlueprintCamelContext            | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | JMX enabled. Using ManagedManagementStrategy.
13:24:58,993 | INFO  | rint Extender: 3 | BlueprintCamelContext            | ?                                   ? | 85 - org.apache.camel.camel-core - 2.8.0.fuse-01-06 | Apache Camel 2.8.0-fuse-01-06 (CamelContext: smxb-pinger) is starting

Using this mechanism you can externalise any environment-specific config. If you like, define some properties to echo a different pong message and have a go at modifying them externally.