Moved to https://slidr.io/azzazzel/osgi-fundamentals
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The document discusses modularity and the OSGi modularity framework. It presents several modularity maturity models with increasing levels of modularity, from monolithic applications to dynamic systems that can adapt to changing requirements. The levels move from being unaware of dependencies to being aware of and managing different types of dependencies. The document also explains how OSGi implements many of these modularity concepts through mechanisms like modules, services, and declarative services.
Moved to https://slidr.io/azzazzel/osgi-fundamentals
- 3. "When I use a word," Humpty Dumpty said, in rather a scornful tone, "it means just what I choose it to mean - neither more nor less."
- 4. Modularity Maturity Model proposed by Dr Graham Charters at the OSGi Community Event 2011 Level 1 Ad Hoc nothing Level 2 Modules decoupled from artifact Level 3 Modularity decoupled from identity Level 4 Loose-Coupling decoupled from implementation Level 5 Devolution decoupled from ownership Level 6 Dynamism decoupled from time
- 5. Level 1 Ad Hoc nothing Level 2 Modules decoupled from artifact Level 3 Modularity decoupled from identity Level 4 Loose-Coupling decoupled from implementation Level 5 Devolution decoupled from ownership Level 6 Dynamism decoupled from time Level 7 Peter Kriens only available to people who are Peter Kriens Modularity Maturity Model proposed by Dr Graham Charters at the OSGi Community Event 2011
- 6. Modularity Maturity Model proposed by Peter Kriens in foreword to “Java Application Architecture” Level 1 Ad Hoc Level 2 Modules Level 3 Modularity Level 4 Loose-Coupling Level 5 Devolution Level 6 Dynamism Unmanaged / chaos Managing dependencies Proper isolation Minimize coupling Service-oriented architecture
- 7. Level 1 Monolith Level 2 Composite Level 3 Containers Level 4 Discovery Level 5 JuServices Buzzword compliant Modularity Maturity Model
- 8. Level 1 Monolith Unaware of own dependencies Level 2 Composite Aware of infrastructural dependencies Level 3 Containers Aware of functional dependencies Level 4 Discovery Aware of functional requirements Level 5 Adapts to changing requirementsJuServices Buzzword compliant Modularity Maturity Model
- 9. Level 1 Monolith Level 2 Composite Level 3 Containers Level 4 Discovery Level 5 JuServices Buzzword compliant Modularity Maturity Model
- 10. Level 1 Monolith Level 2 Composite Level 3 Containers Level 4 Discovery Level 5 JuServices Buzzword compliant Modularity Maturity Model
- 11. Buzzword compliant Modularity Maturity Model JuServices Level 1 Monolith Level 2 Composite Level 3 Containers Level 4 Discovery Level 5
- 12. Buzzword compliant Modularity Maturity Model JuServices Level 1 Monolith Level 2 Composite Level 3 Containers Level 4 Discovery Level 5 OSGi
- 20. Foo Level 2 decoupled from artifact Manifest-Version: 1.0 Bundle-ManifestVersion: 2 Bundle-Name: Foo Bundle-SymbolicName: com.foo Bundle-Vendor: Foo, Inc. Bundle-Version: 1.0.0 . . .
- 21. Buzzword compliant Modularity Maturity Model JuServices OSGi Level 1 Monolith Level 2 Composite Level 3 Containers Level 4 Discovery Level 5 OK!
- 23. Level 3 decoupled from identity Require-Bundle: com.foo Foo Me
- 24. Level 3 decoupled from identity Export-Package ::= export ( ',' export)* List of packages (Java package + version) within this jar file that external code is allowed to access! Foo Me
- 25. Level 3 decoupled from identity Export-Package: com.standard.power.plugs; version=”1.0.0”, com.foo.power.plugs.shop; version=”2.3.0”; uses:=”com.standard.power.plugs”, ... Export-Package ::= export ( ',' export)* List of packages (Java package + version) within this jar file that external code is allowed to access! Foo Me
- 26. Level 3 decoupled from identity Import-Package ::= import ( ',' import )* List of packages (Java package + version-range) that classes in this jar file expect other bundles to provide! Foo Me
- 27. Level 3 decoupled from identity Import-Package: com.standard.power.plugs; version=”[1,2)”, com.foo.power.plugs.shop; version=”2.3.0”, com.other.power.plugs.shop; version=”1.5.0”, ... Foo Me Import-Package ::= import ( ',' import )* List of packages (Java package + version-range) that classes in this jar file expect other bundles to provide!
- 28. Buzzword compliant Modularity Maturity Model JuServices OSGi Level 1 Monolith Level 2 Composite Level 3 Containers Level 4 Discovery Level 5 OK! OK!
- 29. Level 4 decoupled from implementation Artifact Artifact Requirement Need to connect device to power outlet! Capability Can connect device to power outlet! RESOLVER
- 30. Level 4 decoupled from implementation Artifact Artifact Requirement Need to connect device to power outlet! Capability Can connect device to power outlet! RESOLVER Require-Capability: power.supply; filter:=”(& (voltage>110) (voltage<230))”, electrician; filter:=”(& (price<50) (certified=yes))”
- 31. Level 4 decoupled from implementation Artifact Artifact Requirement Need to connect device to power outlet! Capability Can connect device to power outlet! RESOLVER Require-Capability: power.supply; filter:=”(& (voltage>110) (voltage<230))”, electrician; filter:=”(& (price<50) (certified=yes))” org.osgi.framework.system.capabilities.extra= power.supply;voltage:Long=220
- 32. Level 4 decoupled from implementation Artifact Artifact Requirement Need to connect device to power outlet! Capability Can connect device to power outlet! RESOLVER Require-Capability: power.supply; filter:=”(& (voltage>110) (voltage<230))”, electrician; filter:=”(& (price<50) (certified=yes))” org.osgi.framework.system.capabilities.extra= power.supply;voltage:Long=220 Provide-Capability: electrician;price:Long=10;certified=yes
- 33. Buzzword compliant Modularity Maturity Model JuServices OSGi Level 1 Monolith Level 2 Composite Level 3 Containers Level 4 Discovery Level 5 OK! OK! OK!
- 34. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service
- 35. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service manifestmanifest OSGi service registry REGISTER REGISTER manifest Interface Service 1 . . . Service N
- 36. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service manifestmanifest OSGi service registry REGISTER USE manifest Interface Service 1 . . . Service N REGISTER
- 37. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service OSGi service registry SERVLET SERVLET GET GET REGISTER REGISTER HTTPServiceImpl HTTP Service HTTPServiceImpl REGISTER manifest
- 38. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service manifest OSGi service registry HTTP Servlet REGISTER SERVLET SERVLETGET (when needed) HTTPServiceImpl Servlet1 (path=”/1”) Servlet2 (path=”/2”) REGISTER
- 39. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service Register OSGI service (manually) SINGLETON PROPERTIES CONTRACT
- 40. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service Use an OSGI service (manually) DONE WITH THE SERVICE START USING THE SERVCE FIND A SERVCE
- 41. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service Declarative services and Service Component Runtime (SCR)
- 42. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service /OSGI-INF/MyComponent.xml file: <?xml version="1.0" encoding="UTF-8"?> <scr:component name=”MyComponent” xmlns:scr=”http://www.osgi.org/xmlns/scr/v1.2.0”> <implementation class=”com.liferay.MyComponent”/> </scr:component> Manifest header: Service-Component: OSGI-INF/MyComponent.xml
- 43. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service @Component( configurationPid=”hello.component.pid”, configurationPolicy=ConfigurationPolicy.OPTIONAL, enabled=true, immediate=true, name=”HelloComponent”, property={ ”vendor.name=Liferay”, ”other.property=value” }, service={HelloService.class, OtherService.class} ) public class HelloComponent implements MultiService { . . .
- 44. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service @Activate void open(Map<String,?> properties) { } @Deactivate void close() { } @Modified void modified(Map<String,?> properties) { }
- 45. Level 5 decoupled from ownership & time JuServices Artifact Artifact REGISTRY Service Service Service Service @Reference( cardinality=ReferenceCardinality.MANDATORY, name = “LogService”, policy = ReferencePolicy.STATIC, policyOption=ReferencePolicyOption.RELUCTANT, service = LogService.class, target = “(vendor.name=Liferay)”, unbind = “unsetLog”, updated = “updatedLog” ) void setLog( LogService log) { } void unsetLog( LogService log) { } void updatedLog( Map<String,?> ref ) { }
- 46. Buzzword compliant Modularity Maturity Model JuServices OSGi Level 1 Monolith Level 2 Composite Level 3 Containers Level 4 Discovery Level 5 OK! OK! OK! OK!
- 47. The essence of modularity is Not knowing
- 48. The essence of modularity is Not knowing Which enforces optimization for Predictability
- 49. Which results in application Agility The essence of modularity is Not knowing Which enforces optimization for Predictability