Presentation given at the German OSGi Users Forum meeting in Cologne, Germany on December 6th, 2012

1. OSGi
Enterprise Expert Group
David Bosschaert
Principal Engineer, JBoss/Red Hat
david@redhat.com
December 2012

2. Agenda
● What is the EEG?
● New specs in OSGi Enterprise R5
● Work in progress for OSGi Enterprise R6

3. What is the EEG
● One of the 3 active expert groups in the OSGi
Alliance, others are CPEG and REG
● Works on OSGi Specifications that are
applicable to Enterprise use-cases
– but are potentially useful in other contexts too
● Active members include: IBM, RedHat, TIBCO,
Adobe, Oracle, Luminis, Paremus and others
● Previous releases:
– R4.2 (first Enterprise Release, 2010)
– R5 (second Enterprise Release, 2012)

4. New specs in the
Enterprise R5 release

5. Repository Spec (Enterprise R5)
Find resources in a repository...
● based on capabilities
– (not just their name)
– osgi-defined capabilities (exported packages, bsn)
– user-defined capabilities (e.g. passed QA)
● E.g. “find a bundles that provides package
org.acme.foo in version range [1.2, 2)”
● API, can be implemented over existing repos
public Map<Requirement,Collection<Capability>>
findProviders(Collection<Requirement> requirements)
● Can be used with any resource, not just bundles
● Implementation at JBoss
(github: jbosgi-repository)

6. Resolver spec (Enterprise R5)
● Resolve on behalf of a framework
– Given a framework with existing bundles...
– Will a set of bundles resolve?
– What else is needed?
– Transitive dependencies
● Can be used to prepare bundles to-be-installed
● Run what-if scenarios
● Can work seamlessly with the Repository API
● Implementation at Apache Felix

7. Subsystems (Enterprise R5)
● Allows definition of OSGi Applications
– made up of a number of bundles
– other coarse-grained components also possible
● e.g. a library that consists of many bundles
– either an archive that contains bundles (.esa file)
– or just a subsystem desc
● bundles obtained from Repository
● subsystems can be nested
● version ranges can be frozen in a deployment
descriptor

8. Subsystems (Enterprise R5)
● Sharing models
– Feature (everything shared)
– Application (nothing shared out, libraries shared in)
– Composite (custom sharing)

9. Subsystem examples (Enterprise R5)
Two example subsystem definitions
MyZippedApplication.esa: MyDeclarativeApplication.esa:
META-INF/SUBSYSTEM.MF: META-INF/SUBSYSTEM.MF:
Subsystem-SymbolicName: foo Subsystem-SymbolicName: bar
Subsystem-Version: 1.0.0 Subsystem-Type: osgi.subsystem.feature
Subsystem-Type: Subsystem-Content:
osgi.subsystem.application org.acme.b1;
bundle1.jar type=osgi.bundle;
bundle2.jar version=[1.1, 2),
bundle3.jar org.acme.s2;
subsystem4.esa type=osgi.subsystem.feature
META-INF/DEPLOYMENT.MF:
Deployed-Content:
org.acme.b1; deployed-version=1.7.2,
org.acme.s2; deployed-version=1.0.2
Implementation at Apache Aries

10. Migration Support (Enterprise R5)
ServiceLoader Mediator specification
● Enables java.util.ServiceLoader in OSGi
● Implementation at Apache Aries
http://aries.apache.org/modules/spi-fly.html
For any OSGi spec, find the available implementations on
Wikipedia:
http://en.wikipedia.org/wiki/OSGi_Specification_Implementations

11. Capability Namespaces (Enterprise R5)
For use by Framework Resolver, Repository or tools
● osgi.extender
– allows a bundle to say 'I need this extender to run'
– or 'I am this extender'
– prevents system from resolving if extender not there
– can prevent multiple extenders from extending the same
● osgi.contract
– a shorthand for a group of imports (e.g. Servlet, JPA, JAXB)
– primarily for use by tools
● osgi.service
– express that a bundle needs/provides a service
– primarily for use with the Repository

12. Work in progress for R6
● Tentative release date: early 2014
● Current themes:
– Cloud
– JavaEE Integration
– Updating existing specs

13. R6 – Cloud
REST management API (RFC 182)
● A remote management API for OSGi
frameworks over REST (JSON or XML)
● Install/Uninstall/Start/Stop bundles
● Inspect the framework, services etc...
Cloud Ecosystems (RFC 183)
● A fluid, multi-node, service-based PaaS
– deployments can dynamically scale up/down
– move around
– be repurposed

14. R6 – JavaEE integration (1)
● CDI integration (RFC 193)
– Use the CDI programming model to work with OSGi
services
– Integrate across JavaEE and OSGi boundaries
using CDI
● JCA integration (RFC 146)
– Use JCA Resource Adapters in OSGi

15. R6 – JavaEE integration (2)
● EJB integration (RFC 194)
– Deploy and use EJBs in OSGi
● JavaEE Package Versions (RFC 180)
– projects developed for OSGi use semantic
versioning on their Java Packages
– but what versions do I use when I need to import
something from javax.xxx / JSR spec?
– This RFC aims at providing a solution to this

16. R6 – Other Spec Updates
● Blueprint 1.1, Blueprint transactions and
possibly other Blueprint updates
● HttpService is being updated (RFC 189)
– to include support for newer Servlet features
– Whiteboard pattern support
● Declarative Services update (RFC 190)
– a number of updates including an administrative API
and enhanced Annotation support

17. Interested? Come and help out!
● If you're interested in any of the R6 EEG topics,
come and help out!
– the OSGi Alliance is always open for new members:
http://www.osgi.org/Join
– if your employer is already a member, talk to me
(david at redhat.com) or any other co-chair on how
to get involved
● If you're not a member
– regular Early Access Drafts are released for
feedback