title=Content-Package based development type=page status=published tags=development

# Content-Package based development

Sling offers first-class support for [Apache Jackrabbit FileVault](https://jackrabbit.apache.org/filevault/) content packages. FileVault offers a way of mapping content on filesystem to the JCR repository and the other way around. Content packages are an alternative to [the content loader mechanism](/documentation/bundles/content-loading-jcr-contentloader.html), offering a richer tool set and better support for deploying additional entities, such as users, groups, and access control entries.

There are three components of the content packages support:

- client-side tooling for building and installing content packages
- server-side support for installing content packages at runtime
- server-side support for installing content packages at build time

The server-side support for Apache Sling is made of:

- the [Composum Package Manager](https://www.composum.com/home/nodes/pckgmgr.html), implementing the HTTP API that receives and installs content packages
- the [Apache Sling Content Package Installer Factory](/documentation/bundles/content-package-installer-factory.html), allowing the deployment of content packages at build time.

Content packages can be included at build time using either the [provisioning model](/documentation/development/slingstart.html) or the [feature model](/documentation/development/feature-model.html).

The client-side support depends on the toolset used to build the project.

For Maven projects, this support consists of

- the [filevault-package-maven-plugin](https://jackrabbit.apache.org/filevault-package-maven-plugin/) builds content packages from Maven projects
- the [wcmio-content-package-maven-plugin](https://wcm.io/tooling/maven/plugins/wcmio-content-package-maven-plugin/) uploads content packages at runtime to a Sling instance using an HTTP API

For Javascript projects, the suport consists of the [Sling Packager](https://github.com/apache/sling-slingpackager/).

## Creating a content package

### Maven projects

The [Sling Project Archetype](https://github.com/apache/sling-project-archetype) creates a multi-module project that includes content packages as part of its output. To use it, run the following command

    $ mvn archetype:generate -Dfilter=org.apache.sling:sling-project-archetype

then select the latest version of the archetype and fill in the required information.

### Node projects

An example project using the Sling Packager can be found at [peregrine-cms/simple-sling-vue-example](https://github.com/peregrine-cms/simple-sling-vue-example) on GitHub.

## Deploying a content package at runtime

### Maven projects

Building a content package is achieved using the Maven command line

    $ mvn package
    
After starting up Sling, the resulting file can then be deployed using the wcmio-content-package-maven-plugin

    $ mvn wcmio-content-package:install
   
### Node projects

Content packages are built with

    $ npx slingpackager package <folder>

After starting up Sling, the resulting file can then be deployed with

    $ npx slingpackager upload <content-package.zip> -i
 

### Notes

Inspecting the content package reveals that is is just a ZIP file with additional metadata. 

After deploying the content package, ensure that you are logged in to the Sling Starter, and then navigate to the Composum Package Manager at [http://localhost:8080/bin/packages.html](http://localhost:8080/bin/packages.html). You will see the content package as listed and will be able, for instance, to uninstall it.

The [Sling IDE Tooling](/documentation/development/ide-tooling.html) has support for exporting and importing content incrementally to a Sling instance, and can be used alongside the Maven-based tooling.

## Installing a content package at build time

For the content package to be installed at build time, it must be available in a Maven repository at the time when the Sling application is built.

For the provisioning model, the content package must be added to an `artifacts` section, with the zip extension.

    [feature name=my-app]

    [artifacts]
      org.apache.sling.sample/org.apache.sling.sample001/1.0-SNAPSHOT/zip
      
For the feature model, the content package must be added to the `content-packages` section, also with a zip extension:

    {
      "id": "...",
      "content-packages:ARTIFACTS|true": [
        "org.apache.sling.sample:org.apache.sling.sample001:zip:1.0-SNAPSHOT"
      ]
    }