...
The greeter demo can be found in the samples/greeter directory of the SVN code base and implements a simple OSGi Greeter Service and a consumer to that service with a trivial UI.
In this walkthrough all the required bundles are installed straight from the maven release repository, so no need to check out SVN and build anything to get started with the Greeter Demo.
NOTE: this demo requires CXF/DOSGi 1.1-SNAPSHOT
The Greeter demo design
The demo is composed of 3 bundles:
...
Code Block | ||||
---|---|---|---|---|
| ||||
public interface GreeterService { Map<GreetingPhrase, String> greetMe(String name); GreetingPhrase [] greetMe(GreeterData name) throws GreeterException; } |
The GreeterData
interface, GreetingPhase
and GreeterException
classes are also defined by this custom types defined in the Greeter Interface bundle.
In this walkthrough, the following setup will be used:
The client side bundles will be running in Equinox, invoking on a Distributed OSGi Service running in Felix. Note that the choice of containers is completely trivial. Any OSGi container that implements the Service Registry Hooks (a new feature in OSGi 4.2) can be used on either side.
...
Let's run the server in Felix 13.80.01. As a prerequisite it requires some of the OSGi Compendium Specification interfaces. These don't come with the Felix download, but you can install a bundle that contains these interfaces straight from Maven.
In this walkthrough I'm using the single-bundle distribution of CXF/DOSGi which can be installed straight from the Maven release repository.
To set up my Felix environment, I'm running the following commands:
Code Block |
---|
C:\felix-1framework-3.8.0>java -jar bin\felix.jar0.1> Welcome to Apache Felix. ================= -> ps START LEVEL 1 ID State Gogo g! install http://repo1.maven.org/maven2/org/osgi/org.osgi.compendium/4.2.0/org.osgi.compendium-4.2.0.jar g! start http://www.apache.org/dist/cxf/dosgi/1.2/cxf-dosgi-ri-singlebundle-distribution-1.2.jar ... some log messages may appear... g! lb 0|Active Level| Name [ 0|org.apache.felix.framework 0] [Active(3.0.1) 1|Active ] [ | 0] System Bundle 1|org.apache.felix.bundlerepository (1.86.02) [ 1] [2|Active ] [| 1] Apache Felix Shell Service (1.2|org.apache.felix.gogo.command (0.6.0) [ 2] [3|Active ] [| 1] Apache Felix Shell TUI (1.2|org.apache.felix.gogo.runtime (0.6.0) [ 3] [4|Active ] [| 1] Apache Felix Bundle Repository (1.4|org.apache.felix.gogo.shell (0.6.0) -> start http://repo2.maven.org/maven2/org/osgi/org.osgi.compendium/4.1.0/org.osgi.compendium-4.1.0.jar -> start https://repository.apache.org/content/groups/snapshots/org/apache/cxf/dosgi/cxf-dosgi-ri-singlebundle-distribution/1.1-SNAPSHOT/ 5|Resolved | 1|osgi.cmpn (4.2.0.200908310645) 6|Active | 1|cxf-dosgi-ri-singlebundle-distribution- (1.1-SNAPSHOT.jar 2.0) |
Some log messages may come up now.
Note that instead of manually adding these bundles to the Felix container, you can also append the target/felix.config.properties.append
file to the <felix-root>/conf/config.properties
file. This will automatically load these two bundles when Felix starts up.
Now let's start up the server-side greeter bundles. Like with the DOSGi bundle itself, I'm installing these straight from the Maven release repository.
Code Block |
---|
->g! start httpshttp://repositoryrepo1.apachemaven.org/contentmaven2/groups/snapshots/org/apache/cxf/dosgi/samples/cxf-dosgi-ri-samples-greeter-interface/1.1-SNAPSHOT2/cxf-dosgi-ri-samples-greeter-interface-1.1-SNAPSHOT2.jar ->g! start httpshttp://repositoryrepo1.apachemaven.org/content/groups/snapshotsmaven2/org/apache/cxf/dosgi/samples/cxf-dosgi-ri-samples-greeter-impl/1.1-SNAPSHOT2/cxf-dosgi-ri-samples-greeter-impl-1.1-SNAPSHOT.jar -> ps2.jar ... some log messages will appear ... g! lb START LEVEL 1 ID |State Level |Level|Name [ 0] [|Active ] [| 0] |System Bundle (13.80.01) [ 1] [|Active ] [| 1] |Apache Felix ShellBundle ServiceRepository (1.6.2.0) [ 2] [|Active ] [| 1] |Apache Felix ShellGogo TUICommand (10.26.0) [ 3] [|Active ] [| 1] |Apache Felix BundleGogo RepositoryRuntime (10.46.0) [ 4] [Active ] [ 1] OSGi R4 Compendium Bundle|Active | 1|Apache Felix Gogo Shell (0.6.0) 5|Resolved | 1|osgi.cmpn (4.12.0.200908310645) [ 5] [6|Active ] [| 1] |Distributed OSGi Distribution Software Single-Bundle Distribution [ 8] [7|Active ] [| 1] |CXF Distributed OSGi Greeter Demo Interface Bundle [ 9] [8|Active ] [| 1] |CXF Distributed OSGi Greeter Demo Service Implementation Bundle |
At the end of the log messages you will see one appear that says: INFO: TopologyManager: export sucessful Endpoints: Endpoint Description for ServiceReference [
Some more log messages come up. When it says INFO: Remote org.apache.cxf.dosgi.samples.greeter.GreeterService
endpoint has been published into Discovery service you know ]
This means that the service is successfully exposed remotely, and you can verify this by requesting the WSDL:
...
So the remote service is simply looked up the normal way, via the OSGi Service Registry.
How does it get there? The fact that a lookup on a service is done internally triggers a Service Registry Hook. This will go out to any registered Distributed OSGi Discovery implementations and query them for any matching services.
However, in our setup we haven't yet registered a Discovery implementation. There is an alternative, more static way to provide discovery type information, in case this info is not available via discovery. It can be specified in a OSGI-INF/remote-service/*.xml
file. This the content of the Greeter Service Consumer remote-services.xml file:
Code Block | ||||
---|---|---|---|---|
| ||||
<service<endpoint-descriptions xmlns="http://www.osgi.org/xmlns/sdrsa/v1.0.0"> <service<endpoint-description> <provide<property interfacename="org"objectClass"> <array> <value>org.apache.cxf.dosgi.samples.greeter.GreeterService"GreeterService</>value> </array> <property name="service.exported.interfaces">*</property> <property name="serviceendpoint.exported.configs">org.apache.cxf.ws<id">http://localhost:9090/greeter</property> <property name="org"service.imported.configs">org.apache.cxf.ws.address">http://localhost:9090/greeter<ws</property> </serviceendpoint-description> </serviceendpoint-descriptions> |
Let's run the consumer in Equinox, so that we have the bundles running in Equinox talking to a remoted service running in Felix!
As with Felix, we will have to load the bundle with the OSGi compendium interfaces. There's one that ships with Equinox.
Code Block |
---|
/eclipse> java -jar plugins/org.eclipse.osgi_3.56.0.v20090520v20100517.jar -configuration conf -console osgi> install install file:plugins/org.eclipse.osgi.services_3.2.0100.v20090520-1800v20100503.jar Bundle id is 1 osgi> start 1 osgi> install httpshttp://repositorywww.apache.org/content/groups/snapshots/org/apachedist/cxf/dosgi/cxf-dosgi-ri-singlebundle-distribution/1.1-SNAPSHOT2/cxf-dosgi-ri-singlebundle-distribution-1.1-SNAPSHOT2.jar Bundle id is 2 osgi> start 2 ... some log messages may appear... |
Some logging messages may appear. You can also automatically load the DOSGi bundles by appending the target/equinox.config.ini.append to you equinox config.ini file.
Code Block |
---|
osgi> install http://repo2repo1.maven.org/maven2/org/apache/cxf/dosgi/samples/cxf-dosgi-ri-samples-greeter-interface/1.02/cxf-dosgi-ri-samples-greeter-interface-1.02.jar Bundle id is 3 osgi> install http://repo2repo1.maven.org/maven2/org/apache/cxf/dosgi/samples/cxf-dosgi-ri-samples-greeter-client/1.02/cxf-dosgi-ri-samples-greeter-client-1.02.jar Bundle id is 4 osgi> ss Framework is launched. id State Bundle 0 ACTIVE org.eclipse.osgi_3.56.0.v20081201-1815v20100517 1 ACTIVE RESOLVED org.eclipse.osgi.services_3.2.0100.v20081205-1800v20100503 2 ACTIVE cxf-dosgi-ri-singlebundle-distribution 3 INSTALLED cxf-dosgi-ri-samples-greeter-interface 4 INSTALLED cxf-dosgi-ri-samples-greeter-client osgi> start 4 |
After a few moments the following window appears:
The window appears once the ServiceTracker in the consumer has received a callback that the GreeterService
has been found. The value entered will used to invoke the (remote) OSGi service, with a call like this:
...