Welcome to Sling

Sling is a Web application framework based on REST principles that provides easy development of content-oriented applications. Sling uses a JCR repository, such as Apache Jackrabbit, as its data store.

Sling started as an internal project of Day Management AG and has been contributed to the Apache Software Foundation and is currently undergoing incubation. See the Sling status page for more information.

These pages are currently under construction, so please come back now and then, over the next few days, to see what is going on here. Discussion should be directed to the Apache Jackrabbit development list (dev at jackrabbit.apache.org).

Excuse our mess while we redesign Sling has undergone an important redesign in the last few months, and we're not done updating this website yet. The status of each page is indicated by a note like this at the top of each page. Pages which do not have such a note should be considered not reviewed: the information that they contain might be out of sync with the current Sling codebase.

Getting started

If you prefer doing rather than reading, please proceed to Discover Sling in 15 minutes, where you can quickly get started on your own instance of Sling.

Contents

ApacheConUS07 tidbits ApacheCon US 07 Fast Feather Track Presentation on Sling Feathercast On Day 4 with an interview on Sling with Felix

• Project Information
• Some Use Cases for Sling
• The Component API underlying Sling
• Architecture of Sling
• Assembly: Bundling Bundles
• Initial Provisioning and Startup
• Configuration Support
• Logging
• Content Loading and Nodetype Support
• HTTP Request Processing

Advanced Topics

• Eventing and Jobs

Guides

In addition to this more descriptive and referential documentation, a series of user and developer guides are provided here:

• Installing and Upgrading Bundles
• Default Content Mapping and Request Rendering
• Dispatching requests in Sling Applications
• Request Parameter Handling in Sling

References

Apache Jackrabbit

The main purpose of Sling is to develop a content-centric Web Application framework for Java Content Repository (JCR) based data stores. Sling is implemented - with the notable exception of JCR Node Type management - purely in terms of the JCR API and as such may use any JCR compliant repository. The default implementation for Apache Jackrabbit is provided out of the box.

OSGi

Sling is implemented as a series of OSGi Bundles and makes extensive use of the OSGi functionality, such as lifecycle management and the service layer. In addition, Sling requires several OSGi compendium services to be available, such as the Log Service, Http Service, Configuration Admin Service, Metatype Service, and Declarative Services.

Apache Felix

While Sling does not require a specific OSGi framework implementation to run in, Sling is being developed using Apache Felix as the OSGi framework implementation. It has not been tested yet, but it is expected that Sling also operates perfectly inside other OSGi frameworks such as Equinox and Knopflerfish.