More Related Content
Viewers also liked (19)
Similar to Practical OSGi Subsystems (20)
Practical OSGi Subsystems
- 1. Practical OSGi Subsystems Glyn Normington
- 2. Agenda Background Subsystem types Nested subsystems Subsystem content and dependencies Getting started
- 3. Subsystems New in OSGi Enterprise 5.0 spec Implementation underway in Apache Aries Based on input from several projects Aries, Geronimo, Glass鍖sh, Karaf, Paremus Service Fabric,Virgo, WebSphere Best practices...
- 4. Why Subsystems? Many bundles Named, versioned grouping Management Scoping
- 5. Scoping Bundles Packages Capabilities Services
- 7. Feature Subsystems Feature Scoping: bundle bundle None bundle bundle
- 8. Application Subsystems Scoping: Application No exports bundle bundle Automatic imports bundle bundle
- 9. Composite Subsystems Scoping: Composite Con鍖gurable exports bundle bundle Con鍖gurable imports bundle bundle
- 10. Subsystem Types in Practice
- 11. Feature Subsystems Useful for grouping dependencies More controlled than auto-detection Helps avoid uses constraint failures Useful for: Common infrastructure Feature bundle bundle Shared bundles bundle bundle
- 12. Application Subsystems Useful for top layer of the system Application or independent parts of an app Avoid including infrastructure bundles Reduces sharing Application Application Makes update more dif鍖cult bundle bundle bundle bundle Can lead to resolution failures Feature bundle bundle
- 13. Composite Subsystems Essentially a systems programming feature Useful for kernels and special infrastructure Not recommended for general, widespread application use Complex Composite Can duplicate infrastructure bundle bundle extenders management bundles bundle bundle
- 14. Composite Subsystems: Kernels Root (kernel) Composite (user region) bundles packages services
- 15. Subsystem Content and Dependencies
- 16. Subsystem Content By value in a subsystem archive By reference to a repository
- 17. Dependencies Satisfy the requirements of a subsystem But not included in the subsystem content Automatically installed from a repository
- 18. Subsystem Content and Dependencies in Practice
- 19. Use of Repositories Subsystem archive content Easy to deploy May limit sharing Harder to update Repository content Convenient during development Avoids bloated archives Generally preferable
- 21. Nested Subsystems So far all subsystems have been children of the root subsystem Root Application Application bundle bundle bundle bundle Feature bundle bundle
- 22. Nested Subsystems Subsystems can be nested to any depth Sharing between parent and child is controlled by the child
- 23. Nested Subsystems in Practice
- 24. Nested Subsystems Features useful for grouping other subsystems Root Feature Application Application bundle bundle bundle bundle bundle bundle bundle
- 25. Nested Subsystems Nested features useful for logical grouping Root Root Feature Application Feature bundle bundle bundle bundle Feature bundle bundle bundle bundle
- 26. Nested Subsystems Nested applications useful for scoping Root bundle Application Application bundle bundle bundle bundle
- 27. Getting Started
- 28. Trying it out Apache Aries support in development Some Virgo equivalents available
- 29. Aries Subsystems This example runs on Virgo Kernel (Live demo) You can run it yourself in 5 minutes https://github.com/glyn/aries-subsystems- on-virgo-kernel README.md contains full instructions
- 30. Virgo Equivalents Standard Function Virgo Equivalent Feature Unscoped plan Application - scoped using a PAR or scoped plan - scoped region using metadata rewriting Composite - scoped using a User region region Nested plans Nesting PARs, plans, user region Repository Repository Deployment Contexts -
- 31. Thanks I am indebted to John Ross for his help with Aries Subsystems
- 32. Further Information OSGi R5 Enterprise Speci鍖cation http://www.osgi.org/Download/Release5 Aries Subsystems on Virgo Kernel https://github.com/glyn/aries-subsystems-on-virgo-kernel Virgo User & Programmer Guides http://www.eclipse.org/virgo/documentation/