title=How to Create a Custom Feature Model Project type=page status=published tags=featuremodel,sling, kickstarter
### About this How-To <div style="background: #cde0ea; padding: 14px; border-left: 10px solid #f9bb00;"> #### What we'll explore: * Create a sample Sling bundle project * Update the Maven POM to add Feature Model support to the project * Launch our sample application with the Kickstarter #### What you should know: * Skill Level: Intermediate * Environment: Windows/Unix * Time: 20 minutes </div> * Back To: [How to Start Sling with the Kickstarter](/documentation/feature-model/howtos/kickstart.html) * Back to the: [Feature Model How-To Guide](/documentation/feature-model/feature-model-howto.html) ### Prerequisites In order to follow this how-to you'll need the following on your computer: * Java 8 * Maven 3 * Bash shell ### What's the Sling Feature Model The Sling Feature Model provides a robust approach for configuring and assembling OSGi-based applications. Here are some of its high-level capabilities: * Declarative description of an entire application or part of an application * Support for aggregating Feature Models into a single Feature Model for simpler packaging and distribution * Easy application startup through the Feature Launcher or the Kickstarter ### What's a Feature Model project A Feature Model project is a standard Maven project with the following additional features: * Sling Feature Maven Plugin * Kickstarter launch profile ### Step 1: Create a Sling bundle project Let's start by creating a simple Sling project using the traditional Maven [Sling Bundle Archetype](/documentation/development/maven-archetypes.html#sling-jcrinstall-bundle-archetype-1). $ mvn -X archetype:generate -DarchetypeGroupId=org.apache.sling -DarchetypeArtifactId=sling-bundle-archetype \ -DgroupId=org.apache.sling.example \ -DartifactId=feature-model-sample \ -Dversion=1.0.0-SNAPSHOT \ -Dpackage=org.apache.sling.example $ cd feature-model-sample <div style="background: #cde0ea; padding: 14px; border-left: 10px solid #f9bb00;"> **Note:** There are plans to introduce a Maven archetype that will create a Maven project with support for Feature Models. </div> ### Step 2: Update the POM Now, let's update the POM and add a few elements to layer on support for Feature Models. **1.** Add the following to the `<properties>` element. <slingfeature-maven-plugin.version>1.3.4</slingfeature-maven-plugin.version> <sling-kickstart-maven-plugin.version>0.0.2</sling-kickstart-maven-plugin.version> <oak.version>1.26.0</oak.version> **2.** Add the [Sling Feature Maven Plugin](https://sling.apache.org/components/slingfeature-maven-plugin/plugin-info.html) under `<build>` -> `<plugins>`. <plugin> <groupId>org.apache.sling</groupId> <artifactId>slingfeature-maven-plugin</artifactId> <version>${slingfeature-maven-plugin.version}</version> <extensions>true</extensions> <executions> <execution> <id>create-fm</id> <phase>package</phase> <goals> <goal>include-artifact</goal> </goals> </execution> <execution> <id>aggregate-configuration</id> <phase>package</phase> <goals> <goal>aggregate-features</goal> </goals> <configuration> <aggregates> <aggregate> <classifier>feature_model_sample</classifier> <filesInclude>**/*.json</filesInclude> <title>Sling Sample Feature Model</title> </aggregate> </aggregates> </configuration> </execution> <execution> <id>install-fm</id> <phase>package</phase> <goals> <goal>attach-features</goal> </goals> </execution> </executions> </plugin> The Sling Feature Maven Plugin is responsible for creating a Feature Model JSON file for your project. The only pieces that change from project to project are the `<classifier>` and `<title>` element values. Set these values to something descriptive for your project. The classifier value will be used as part of the Feature Model JSON filename: `target/slingfeature-tmp/feature-`_classifier_`.json` <div style="background: #cde0ea; padding: 14px; border-left: 10px solid #f9bb00; margin-bottom: 1em;"> Make a note of `target/slingfeature-tmp/feature-feature_model_sample.json` as this path will be used in the next section. </div> **3.** Add a Maven profile called `launch` under `<project>` -> `<profiles>`. <profile> <id>launch</id> <build> <plugins> <plugin> <groupId>org.apache.sling</groupId> <artifactId>sling-kickstart-maven-plugin</artifactId> <version>${sling-kickstart-maven-plugin.version}</version> <extensions>true</extensions> <executions> <execution> <id>start-sling</id> <phase>install</phase> <goals> <goal>start</goal> </goals> </execution> </executions> <configuration> <launchpadDependency> <groupId>org.apache.sling</groupId> <artifactId>org.apache.sling.kickstart</artifactId> <version>0.0.3-SNAPSHOT</version> </launchpadDependency> <parallelExecution>false</parallelExecution> <keepLaunchpadRunning>true</keepLaunchpadRunning> <servers> <server> <port>8080</port> <controlPort>8081</controlPort> <additionalFeatureFile> target/slingfeature-tmp/feature-feature_model_sample.json </additionalFeatureFile> <debug>true</debug> </server> </servers> </configuration> </plugin> </plugins> </build> </profile> This profile is responsible for starting your application using the Kickstarter. Simply, set the `<additionalFeatureFile>` to the file in your target directory that contains your application's Feature Model JSON. ### Step 4: Launch your application $ mvn clean install -Plaunch Now, log into Sling and visit the System Console. You should see your bundle (`feature-model-sample`) listed. ## Mission Accomplished <div style="background: #cde0ea; padding: 14px; border-left: 10px solid #f9bb00; margin-bottom: 1em;"> #### What we learned: * How to update a traditional Sling bundle project to support Feature Models * How to start your project with the Kickstarter </div> Well, that was fun. We'll revisit this sample project soon, But first, let's see how the Feature Model can help us handle complex application configurations. In the next section, we'll take a look at the Composite NodeStore and how to configure it with the Feature Model. <div style="background: #cde0ea; padding: 14px; border-left: 10px solid #f9bb00; margin-bottom: 1em;"> * Next Up: [How to Create a Sling Composite Node Store](/documentation/feature-model/howtos/create-sling-composite.html) * Back to the: [Feature Model How-To Guide](/documentation/feature-model/feature-model-howto.html) </div>