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This chapter will guide you through the steps needed to extend the console and create a new shell. We will leverage Maven, Spring, Spring-DM and OSGi, so you will need some knowledge of those products.

As an example, we will create a command that will leverage the OSGi ConfigAdmin to display the existing configurations.

Create the project using maven

We first need to create the project using maven. Let's leverage maven archetypes for that.

Command line

Using the command line, we can create our project:

Code Block


mvn archetype:create \
  -DarchetypeArtifactId=maven-archetype-quickstart \
  -DgroupId=org.apache.servicemix.kernel.gshell \
  -DartifactId=org.apache.servicemix.kernel.gshell.config \
  -Dversion=1.0-SNAPSHOT

This generate the main pom.xml and some additional packages.

Interactive shell

You can also use the interactive mode for creating the skeleton project:

Code Block
mvn archetype:generate

Use the following values when prompted:

Code Block


Choose a number:  (1/2/3/4/5/6/7/8/9/10/11/12/13/14/15/16/17/18/19/20/21/22/23/24/25/26/27/28/29/30/31/32/33/34/35/36) 15: : 15
Define value for groupId: : org.apache.servicemix.kernel.gshell
Define value for artifactId: : org.apache.servicemix.kernel.gshell.config
Define value for version:  1.0-SNAPSHOT: : 
Define value for package: : org.apache.servicemix.kernel.gshell.config

Manual creation

Alternatively, you can simply create the directory org.apache.servicemix.kernel.gshell.config and create the pom.xml file inside it:

Code Block

title	pom.xml
lang	xml


<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>org.apache.servicemix.kernel.gshell</groupId>
  <artifactId>org.apache.servicemix.kernel.gshell.config</artifactId>
  <packaging>jar</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>org.apache.servicemix.kernel.gshell.config</name>
  <url>http://maven.apache.org</url>
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
</project>

Dependencies

We need to tell maven which libraries our project depends on. In the dependencies section of the pom, add the following ones:

Code Block

lang	xml


  <dependency>
    <groupId>org.apache.felix</groupId>
    <artifactId>org.osgi.core</artifactId>
    <version>1.0.0</version>
    <scope>provided</scope>
  </dependency>
  <dependency>
    <groupId>org.apache.servicemix.kernel.gshell</groupId>
    <artifactId>org.apache.servicemix.kernel.gshell.core</artifactId>
    <version>1.0-m2</version>
  </dependency>
  <dependency>
    <groupId>org.springframework.osgi</groupId>
    <artifactId>spring-osgi-core</artifactId>
    <version>1.0</version>
  </dependency>

These are needed respectively for OSGi, ServiceMix Kernel commands support and Spring-DM.

Additionally, we need the ConfigAdmin service, which is in the OSGi Compendium jar:

Code Block

lang	xml


  <dependency>
    <groupId>org.apache.felix</groupId>
    <artifactId>org.osgi.compendium</artifactId>
    <version>1.0.0</version>
    <scope>provided</scope>
  </dependency>

Loading the project in your IDE

We can use maven to generate the needed files for your IDE:

Inside the project, run the following command

Code Block
mvn eclipse:eclipse

or

Code Block
mvn idea:idea

The project files for your IDE should now be created. Just open the IDE and load the project.

Creating a basic command class

We can now create the command class ListCommand.java

Code Block

title	ConfigList.java
lang	java


package org.apache.servicemix.kernel.gshell.config;

import org.apache.geronimo.gshell.support.OsgiCommandSupport;
import org.apache.geronimo.gshell.command.annotation.CommandComponent;

@CommandComponent(id="config:list", description="List the available configurations")
public class ListCommand extends OsgiCommandSupport {

    protected Object doExecute() throws Exception {
        io.out.println("Executing List command");
        return null;
    }
}

Creating the associated spring configuration files

The spring configuration files will be used to create the command and register it in the OSGi registry, which is the way to make the command available to the ServiceMix Kernel console. This spring file must be located in the META-INF/spring/ directory inside the bundle.

If you don't have the src/main/resources directory yet, create it.

Code Block
mkdir src/main/resources

Then, re-generate the IDE project files and reload it so that this folder is now recognized as a source folder.

Inside this directory, create the META-INF/spring/ directory and put the following file inside (the name of this file has no impact at all):

Code Block

title	gshell-config.xml
lang	xml


<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:osgi="http://www.springframework.org/schema/osgi"
       xmlns:osgix="http://www.springframework.org/schema/osgi-compendium"
       xmlns:util="http://www.springframework.org/schema/util"
       xsi:schemaLocation="
  http://www.springframework.org/schema/beans
  http://www.springframework.org/schema/beans/spring-beans.xsd
  http://www.springframework.org/schema/util
  http://www.springframework.org/schema/util/spring-util.xsd
  http://www.springframework.org/schema/osgi
  http://www.springframework.org/schema/osgi/spring-osgi.xsd
  http://www.springframework.org/schema/osgi-compendium
  http://www.springframework.org/schema/osgi-compendium/spring-osgi-compendium.xsd">

  <bean id="list" class="org.apache.servicemix.kernel.gshell.config.ListCommand" />

  <osgi:service ref="list" interface="org.apache.geronimo.gshell.command.Command">
    <osgi:service-properties>
      <entry key="shell" value="config"/>
      <entry key="alias" value="list"/>
    </osgi:service-properties>
  </osgi:service>

</beans>

Compiling the jar

Let's try to build the jar. Remove the test classes and sample classes if you used the artifact, then from the command line, run:

Code Block
mvn install

If you see something like that:

Code Block


[ERROR] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Compilation failure
/Users/gnodet/work/servicemix/smx4/tmp/org.apache.servicemix.kernel.gshell.config/src/main/java/org/apache/servicemix/kernel/gshell/config/ListCommand.java:[6,1] annotations are not supported in -source 1.3
(try -source 1.5 to enable annotations)
@CommandComponent(id="config:list", description="List the available configurations")

that's because we forgot to enable Java 5. So let's add that to the pom:

Code Block

lang	xml


  <build>
    <pluginManagement>
      <plugins>
        <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-compiler-plugin</artifactId>
          <configuration>
            <source>1.5</source>
            <target>1.5</target>
          </configuration>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>

Let's try again, and we should now have:

Code Block
[INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESSFUL [INFO] ------------------------------------------------------------------------

Turning the jar into an OSGi bundle

OSGi bundles are jars but they require some manifest headers to be correctly recognized. We will leverage Felix's manven plugin to easily generate those.

Lets turn it into a bundle: modify the line in the pom.xml to adjust the packaging:

Code Block

lang	xml


  <packaging>bundle</packaging>

Add the following section at the bottom of the pom.xml

Code Block

lang	xml


  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.felix</groupId>
        <artifactId>maven-bundle-plugin</artifactId>
        <version>1.4.0</version>
        <extensions>true</extensions>
        <configuration>
          <instructions>
            <Bundle-SymbolicName>${adad}</Bundle-SymbolicName>
            <Import-Package>org.apache.geronimo.gshell.command,*</Import-Package>
            <Spring-Context>*;publish-context:=false;create-asynchronously:=false</Spring-Context>
          </instructions>
        </configuration>
        <dependencies>
          <dependency>
            <groupId>
          </dependency>
        </dependencies>
      </plugin>
    </plugins>
  </build>

Let's compiled it again using the mvn install command.

Test in ServiceMix Kernel

Launch a ServiceMix Kernel instance and run the following command to install are newly created bundle:

Code Block
osgi install -s mvn:org.apache.servicemix.kernel.gshell/org.apache.servicemix.kernel.gshell.config/1.0-SNAPSHOT

If you run the help command, you should now see our new sheel config.
Let's try running the command:

Code Block
gnodet@Guillaume-Nodets-MacPro.local:/> config list Executing List command

Yeah TODO

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Versions Compared

Old Version 1

New Version 2

Key

Create the project using maven

Command line

Interactive shell

Manual creation

Dependencies

Loading the project in your IDE

Creating a basic command class

Creating the associated spring configuration files

Compiling the jar

Turning the jar into an OSGi bundle

Test in ServiceMix Kernel