Sling Distribution

Sling Distribution

The Sling Content Distribution module main goal is allowing distribution of content (Sling resources) among different Sling instances. The term "distribution" here means the ability of picking one or more resources on a certain Sling instance in order to copy and persist them onto another Sling instance. The Sling Content Distribution module is able to distribute content by:

• "pushing" from Sling instance A to Sling instance B
• "pulling" from Sling instance B to Sling instance A
• "synchronizing" Sling instances A and B via a (third) coordinating instance C

Distribution Agents Configuration:

These are osgi configurations. These could be

• Forward
• Reverse
• Queue
• Sync

Usecases :

1. Forward distribution : Transfers contents from author to publish instances
2. Reverse distribution : From publish instance to author instances (UGC contents). 
3. Sync distribution : Transfer contents to two publish instances via author instance.
4. Queue distribution : Sending contents one by one. This is not feasible for production.

Example & scenarios :

User Synchronization in AEM using sync distribution

• users, user profiles and user groups created on publish are not created on author
• Sling distribution sets properties in jcr events, making it possible to act within publish-side event listeners without concern for infinite replication loops
• Sling distribution only sends user data to non-originating publish instances, eliminating unnecessary traffic
• ACLs set in the user node are included in the sychronization

When the topology is a publish farm and user sync has been correctly configured, the user and user profile is synchronized across the publish farm using Sling distribution.