Nuxeo World 2011 - Overview of Content Repositories and the Eclipse Apricot Platform

1. Eclipse Apricot
Overview of Content
Repositories and the Eclipse
Apricot Platform
Florent Guillaume, Bogdan Stefanescu
2011-10-20
Open Source ECM

2. Agenda
• What Is a Content Repository?
• Eclipse Apricot: Features & Benefits
• Apricot Modularity
• The Future of Apricot
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3. What Is a
Content Repository?
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4. What Is Content?
• Everything is content!
• Unstructured
• Files, Images, Assets, XML, Binary streams
• Structured
• Schema, Metadata, Business Data, Tables
• Semi-Structured
• Files + Metadata, Web pages (assemblies, relations),
Emails (attachments), Record Management 4

5. A Content Repository is
Middleware
• Between Application and Storage Subsystem
• Does not replace either
• Persistence Service
• Stores structured and unstructured content
• High-Level Abstraction
• Stop caring about storage details
• Focus on your domain model and its objects
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6. What a Content Repository Is
Not
• Not a CMS (WCM, ECM, ...)
• A CMS is one application on top of a Content Repository
• Not a filesystem
• If all you have is a filesystem, everything looks like a file
• Not an ORM
• Not that granular, don’t think in SQL terms
• Not just for storage
• Provides Services, Domain Model / Business Model
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7. Eclipse Apricot
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8. Eclipse Apricot
• OSGi framework
• Under the Eclipse Runtime project
• Currently in the Incubation phase
• Mentored by Gary Xue (Actuate) and Cédric Brun (Obeo)
• Contributed by Nuxeo, from Nuxeo Core
• http://www.eclipse.org/apricot
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9. What Is Apricot?
• Content Repository
• Web Support
• Content Automation
• CMIS
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10. Apricot: Content Repository
• Types and Schema definition
• Persistence
• Query
• Access Control
• Locking
• Versioning
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11. Apricot: Web Support
• Expose content on the web
• Fast framework based on JAX-RS
• Provides FreeMarker templating (pluggable)
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12. Apricot: Content Automation
• Based on Commands/Operations
• Build reusable business logic
• Accessible from UI frameworks and HTTP/ReST
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13. Apricot: CMIS
• OASIS Content Management Interoperability Services
• HTTP APIs (SOAP, AtomPub, Browser Bindings)
• Java APIs (OpenCMIS)
• http://docs.oasis-open.org/cmis/CMIS/v1.0/cmis-
spec-v1.0.html
• http://www.slideshare.net/efge/cmis-and-apache-
chemistry-apachecon-2010
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14. HTTP (CMIS) HTTP
OpenCMIS Java
OpenCMIS Automation
API
Native Java API Core Services
VCS
Binary Store SQL Backend Other Backend
Filesystem SQL Database Cloud 14

15. When to Use Apricot?
• Need to store Objects with Properties
• And also Files
• Don’t want to write SQL
• But be able to fall back to SQL if really needed
• Need Access Control
• Need Versioning, Queries, ...
• Don’t want to reinvent the wheel
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16. Why Is Apricot Good?
• Modular
• Fast
• Safe
• Scales
• Full-featured services
• Battle-tested
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17. Apricot: Modular
• Uses OSGi deployment
• OSGi bundles
• Dynamic lifecycle
• Extension points
• XML
• Inspired by those from Eclipse
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18. Apricot: Fast
• Efficient use of storage backends
• Use their native features and strengths
• Don’t reinvent transactions, relations
• Caching
• Batching
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19. Apricot: Safe
• Transaction-aware
• Rollback everything at once
• Hot backups
• Don’t stop the system
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20. Apricot: Scaling
• Clusterable on top of a standard SQL database
• Architecture ready for NoSQL backends
• Pluggable Binary Store
• Filesystem, SQL, Amazon S3, etc.
• Lockless
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21. Apricot: Full-Featured
Services
• Queries (NXQL, CMISQL, pluggable)
• Versioning (pluggable)
• Locking (synchronous, cluster-aware)
• Access Control (groups, grant/deny, inheritance)
• Proxies (shortcuts)
• Events & Listeners (sync, async, async post-
commit)
• Audit Trail 21

22. Apricot: Battle-Tested
• Originates from Nuxeo Core
• Used in Nuxeo DM, Nuxeo DAM, Nuxeo CMF
• In production for 4 years
• Thousands of deployments
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23. Apricot and Modularity
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24. Choosing a Modularity
Framework
• Java SE
• No bundle life cycle, no modularity, no extension system
• Java EE
• All is packaged as one big application (EAR or WAR),
cannot update or add a feature without recompiling the
entire application
• OSGi — yes, but...
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25. Additions Needed to OSGi
• To achieve a plugin model
• Eclipse already had the answer: extension points
• To provide enterprise features
• No real OSGi Enterprise Framework implementations yet
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26. Extension Points
• Eclipse used EXSD, which is very tied to PDE
• (remember it was 2006 and we had to use maven)
• Nuxeo redefined something similar but more flexible
• No intermediate object model between services and
contributed extensions
• Write an extension class and map it to XML using Java
annotations
• Easy to write for developers, no specific IDE needed
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27. Extension Point Example
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28. Integrating with Java EE
• Apricot should be able to run in an Application Server
(as a WAR)
• Java EE configuration is monolithic
• To declare servlets (web.xml) one must know in advance
the servlets provided by all the different bundles, same for
application.xml
• Apricot is dynamic: bundles may be installed at
runtime
• Java EE components declared by bundles must be
installed at runtime 28

29. Nuxeo Configuration
Fragments
• Using templates for Java EE configuration files
• Dynamically generate web.xml and application.xml at
application startup from the configuration contributed by
each bundle
• Ability to package WAR applications that can adapt
themselves to the configuration provided by new
application bundles
• No need to have different product packagings for different
configurations
• Needs a server-specific bridge to do this processing 29

30. Configuration Fragment
Example
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31. Apricot Configuration
Fragments
• Convert all configuration fragments into runtime
extension points
• Declaring a servlet is done by contributing an extension
point
• Servlets can be installed at runtime when the bundle
declaring them is activated
• Provide a bridge to interact with the host
application server
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32. Java EE Features
• Full OSGi integration of JAAS (authentication system)
• Full JTA support through Apache Geronimo
(transactions)
• Full JCA support through Apache Geronimo
(resource adapters and pooling)
• In-memory JNDI server
• Future plans to integrate the work done in the Gemini
project (and also support Virgo)
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33. The Future of Apricot
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34. Where Are We Going?
• Finish Apricot first release
• Cleanup, testing framework
• Replace Nuxeo Core with Apricot
• Nuxeo Core running under a full OSGi container
• Bridge for non-OSGi application servers
• Update JSF and Seam to Java EE 6
• Use CDI for easier access to services
• Better IDE support 34

35. Thank You!
#NxW11
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36. Additional Information & Links
• http://www.eclipse.org/apricot
• http://github.com/nuxeo/org.eclipse.ecr
• http://www.slideshare.net/efge/cmis-and-apache-
chemistry-apachecon-2010
• http://docs.oasis-open.org/cmis/CMIS/v1.0/cmis-
spec-v1.0.html
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