This document provides an overview and introduction to Adobe Experience Manager (AEM), including its key components and architecture. It discusses AEM's content services, use of Sling and JCR technologies, and how content is stored and replicated using the Oak storage layer with implementations like TarMK and MongoMK. The document also provides information on AEM's RESTful principles, OSGi framework, and common deployment topologies.

1. { + }

2. Agenda
• Intro to AEM
• OAK
• MongoMK

3. 3
What is AEM?
A set of content management
services built on a content-centric
Web application framework on top of
a Java Content Repository

4. 4
What’s inside?
• Content Management Services - Author
interfaces, workflow engine, etc.
• Web Application Framework - Sling/OSGi
• Content Services - JCR

5. 5
Key Principles
• RESTful!!
• OSGi driven
– Web service registry
– Track dependencies
– Avoid collisions
• Sling application framework
– Content-driven
– Scripting inside

6. 6
Technology Stack
AEM Content Services
Sling
JCR
OSGi

7. 7
Stack (continued)
• Sling
– Application Controller driven by URL and supporting RESTful
communication
• JCR
– Java Content Repository
– OAK 1.0.8 implementation
• OSGi
– Universal middleware, dynamic module system.
– Service centric, component-based environment.
– Standardized software life-cycle management

8. 8
AEM Content Services
• CMS application:
• creation, revision, publication, translation, archival and deletion
• task management, portal management, collaboration
• cooperative and automated business processes to move the
content through its lifecycle
• intelligent versioning of content as it moves through its lifecycle
• Tech:
• Ajax / JavaScript user interface, APIs, and libraries
• Direct client-side JavaScript access to JCR content
• Workflow engine – controls the processing of workflow instances
– Workflow instances often control the process of generating and publishing
content

9. 9
Sling
• Maps content objects to components
• Server-side and AJAX scripting support
• Can be used with a range of scripting languages
• JSP
• ESP
• Ruby
• Scala

10. Sling architecture

11. URL Decomposition
• Path – resource/servlet
• Selector – servlet/function
• Extension – Content format
• Suffix path – additional info for processing
• Params – additional info for processing
protocol host path selector extension
http:// myhost/ tools/spy .print.a4 .html /
suffix
a/b ?
param(s)
x=12

12. Architecture
12 Matija Grguric
https://www.flickr.com/photos/matijagrguric/4494622971/in/pool-lego

13. CQ5 Deployment – Topology
Publish Delivery *
13
AEM
CRX
CDN*
Load
Balancer
Dispatcher
Dispatcher
Cluster
Forward & Reverse
Replication of Content
and Application Packages
Visitor Traffic
Cache Invalidation
AEM
CRX
AEM
CRX
Content Delivery
Network
Cache Invalidation
Author

14. 14
AEM Replication
Author Publish
Authors, Developers
create Templates & Pages
Activate/Publish
Visitors request
Pages

15. OAK
a.k.a JCR 3
15

16. Design Goals
• Scalability
– Support big distributed repositories
– Improved write throughput
– Parallel Writes
• Support for more child nodes
• Support for more ACLs
• Built in clustering. Instead of built on top
• OSGi friendly

17. OAK Architecture

18. MK
• TarMK
– Similar to TarPM without clustering and better
performing.
– Persists to Tar files
• MongoMK
– New, MVCC based persistence
– Persists to MongoDB.

19. MongoMK
• Exposes Micro kernel API
• Implements a DocumentStore
– DocumentMK and DocumentNodeStore
• MVCC Approach
• GIT/SVN-inspired DAG-based versioning model [0]
• [0] http://wiki.apache.org/jackrabbit/RepositoryMicroKernel?action=AttachFile&do=view&target=MicroKernel+Revision+Model.pdf

20. MongoMK Data Structure
• simple JSON data model
• properties are name/value pairs
• supported property types:
– String
– Number
– Boolean
– Array
– BSON

21. MongoDB Nodes
{
"_id": "10:/content/dam/geometrixx-media/articles/jp/2012/November/sparrow-post.txt/jcr:content/related",
"_lastRev": {
"r0-0-1": "r1497e6ac359-0-1"
},
"_commitRoot": {
"r1497e6ac359-0-1": "0"
},
"_deleted": {
"r1497e6ac359-0-1": "false"
},
"_modified": NumberLong(1415165165),
"jcr:primaryType": {
"r1497e6ac359-0-1": ""nam:nt:unstructured""
},
":childOrder": {
"r1497e6ac359-0-1": ""[0]:Name""
},
"_modCount": NumberLong(1)
}

22. MVCC
• In JCR 2 sessions always reflects the latest state of the
repository.
• In Oak a session reflects a view of the repository from
the time the session was acquire
Counter = 1
Session 1
Counter = 0
Session 2
Counter = 0
getCounter()?
returns 0
Counter+1 = 1
Time
Counter = 1
Counter+1 = 1
JCR
Counter = 0

23. Recommended deployment
23

24. http://docs.adobe.com/docs/en/aem/6-0/deploy/recommended-deploys.html