OSGi Specs Carsten Ziegeler David Bosschaert 1 of 53 Speakers - - PDF document

▶
osgi specs
SMART_READER_LITE
LIVE PREVIEW

OSGi Specs Carsten Ziegeler David Bosschaert 1 of 53 Speakers - - PDF document

Sep 06, 2022 305 likes •850 views

What's cool in the new and updated OSGi Specs Carsten Ziegeler David Bosschaert 1 of 53 Speakers Carsten Ziegeler (cziegeler@apache.org) RnD Adobe Research Switzerland OSGi Board, CPEG and EEG Member ASF member David Bosschaert

slide-1
SLIDE 1

Carsten Ziegeler David Bosschaert

What's cool in the new and updated

OSGi Specs

1 of 53

slide-2
SLIDE 2

Speakers

Carsten Ziegeler (cziegeler@apache.org) ⦿ RnD Adobe Research Switzerland ⦿ OSGi Board, CPEG and EEG Member ⦿ ASF member David Bosschaert (davidb@apache.org) ⦿ RnD Adobe Research Dublin ⦿ Co-chair OSGi EEG ⦿ Open-source and cloud enthusiast

2 of 53

slide-3
SLIDE 3

Agenda

⦿ Framework updates ⦿ Repository update ⦿ Asynchronous Services & Promises ⦿ Declarative Services ⦿ Http Service ⦿ Cloud ⦿ Semantic Versioning Annotations ⦿ Other spec updates

3 of 53

slide-4
SLIDE 4

OSGi Core R6 Release

⦿ Service Scopes ⦿ Package and Type Annotations ⦿ Data Transfer Objects ⦿ Native Namespace ⦿ WeavingHook Enhancements ⦿ System Bundle Framework Hooks ⦿ Extension Bundle Activators ⦿ Framework Wiring

4 of 53

slide-5
SLIDE 5

Framework Updates Service Scopes (RFC 195)

OSGi R5 supports two service scopes: ⦿ Singleton ⦿ Bundle (ServiceFactory) Transparent to the client

S getService(S Se er rv vi ic ce eR Re ef fe er re en nc ce e<S> r re ef f) v vo

  • i

id d ungetService(S Se er rv vi ic ce eR Re ef fe er re en nc ce e<S> r re ef f)

5 of 53

slide-6
SLIDE 6

Framework Updates Service Scopes (RFC 195)

⦿ Third Scope: prototype ⦿ Driver: Support for EEG specs (EJB, CDI) ⦿ Usage in other spec updates Clients need to use new API / mechanisms

6 of 53

slide-7
SLIDE 7

Framework Updates Service Scopes (RFC 195)

New BundleContext Methods API

S getServiceObjects(S Se er rv vi ic ce eR Re ef fe er re en nc ce e<S> r re ef f).getService() v vo

  • i

id d getServiceObjects(S Se er rv vi ic ce eR Re ef fe er re en nc ce e<S> r re ef f).ungetService(S)

Transparent to the client

7 of 53

slide-8
SLIDE 8

Framework Updates Service Scopes (RFC 195)

⦿ New PrototypeServiceFactory interface ⦿ Managed service registration properties for inspection ⦿ Support in component frameworks (DS, Blueprint)

8 of 53

slide-9
SLIDE 9

Data Transfer Objects

9 of 53

slide-10
SLIDE 10

RFC 185 – Data Transfer Objects

⦿ Defines a DTO model for OSGi

⦿ Serializable/Deserializable objects

⦿ Use cases: REST, JMX, Web Console... ⦿ To be adopted by other specs

10 of 53

slide-11
SLIDE 11

RFC 185 – Data Transfer Objects

Getting DTOs: adapter pattern

p pu ub bl li ic c c cl la as ss s B Bu un nd dl le eD DT TO O e ex xt te en nd ds s org.osgi.dto.DTO { p pu ub bl li ic c l lo

  • n

ng g id; p pu ub bl li ic c l lo

  • n

ng g lastModified; p pu ub bl li ic c i in nt t state; p pu ub bl li ic c S St tr ri in ng g symbolicName; p pu ub bl li ic c S St tr ri in ng g version; }

11 of 53

slide-12
SLIDE 12

RFC 185 – Data Transfer Objects

DTOs for the OSGi framework ⦿ FrameworkDTO ⦿ BundleDTO ⦿ ServiceReferenceDTO ⦿ BundleStartLevelDTO, FrameworkStartLevelDT ⦿ CapabilityDTO, RequirementDTO, ResourceDTO ⦿ BundleWiringsDTO, etc

12 of 53

slide-13
SLIDE 13

Repository 1.1

13 of 53

slide-14
SLIDE 14

OSGi Repository today

14 of 53

slide-15
SLIDE 15

Example Repository namespaces

15 of 53

slide-16
SLIDE 16

RFC 187 - Repository 1.1

Existing repository powerful but: limited to queries in a single namespace New in RFC 187:

Combine requirements spanning multiple namespaces:

R Re ep po

  • s

si it to

  • r

ry y repo = ... // Obtain from Service Registry C Co

  • l

ll le ec ct ti io

  • n

n<R Re es so

  • u

ur rc ce e> res = repo.findProviders( repo.getExpressionCombiner().a an nd d( repo.newRequirementBuilder("osgi.wiring.package"). addDirective("filter","(osgi.wiring.package=foo.pkg1)"). buildExpression(), repo.newRequirementBuilder("osgi.identity"). addDirective("filter", "(license=http://opensource.org/licenses/Apache-2.0)"). buildExpression()));

16 of 53

slide-17
SLIDE 17

Asynchronous Services & Promises

17 of 53

slide-18
SLIDE 18

Async Services

  • Asynchronously invoke services

existing service new ones, written for async access

  • Client invokes the service via a mediator
  • Invocation returns quickly

result can be obtained later

18 of 53

slide-19
SLIDE 19

Async Services - example

A typical service:

p pu ub bl li ic c i in nt te er rf fa ac ce e C Ca al lc cS Se er rv vi ic ce e { B Bi ig gI In nt te eg ge er r factorial(i in nt t num); }

Invoke it asynchronously:

C Ca al lc cS Se er rv vi ic ce e mySvc = ... // from service registry A As sy yn nc c asyncService = ... // from service registry C Ca al lc cS Se er rv vi ic ce e myMediator = asyncService.mediate(mySvc); f fi in na al l P Pr ro

  • m

mi is se e<B Bi ig gI In nt te eg ge er r> p = asyncService.call( myMediator.factorial(1000000)); // ... factorial invoked asynchronously ... // callback to handle the result when it arrives p.onResolve(n ne ew w R Ru un nn na ab bl le e() { p pu ub bl li ic c v vo

  • i

id d run() { S Sy ys st te em m.o

  • u

ut t.println("Found the answer: " + p.getValue()); } });

19 of 53

slide-20
SLIDE 20

OSGi Promises

  • Inspired by JavaScript Promises

Make latency and errors explicit

  • Provide async chaining mechanism

Based on callbacks

  • Promises are Monads
  • Works with many (older) Java versions
  • Designed to work with Java 8

CompletableFuture and Lambdas

  • Used with Async Services

Also useful elsewhere

20 of 53

slide-21
SLIDE 21

OSGi Promises - example

S Su uc cc ce es ss s<S St tr ri in ng g,S St tr ri in ng g> transformResult = n ne ew w S Su uc cc ce es ss s<>() { p pu ub bl li ic c P Pr ro

  • m

mi is se e<S St tr ri in ng g> call(P Pr ro

  • m

mi is se e<S St tr ri in ng g> p) { r re et tu ur rn n P Pr ro

  • m

mi is se es s.resolved(toHTML(p.getValue())); } }; P Pr ro

  • m

mi is se e<S St tr ri in ng g> p = asyncRemoteMethod(); p.t th he en n(validateResult) .t th he en n(transformResult) .t th he en n(showResult, showError);

21 of 53

slide-22
SLIDE 22

Declarative Services

22 of 53

slide-23
SLIDE 23

RFC 190 - Declarative Services Enhancements

⦿ Support of prototype scope ⦿ Introspection API ⦿ DTOs ⦿ But most importantly...

23 of 53

slide-24
SLIDE 24

Simplify Component Dvlpmnt

@Component(p pr ro

  • p

pe er rt ty y={ M My yC Co

  • m

mp po

  • n

ne en nt t.PROP_ENABLED + ":Boolean=" + M My yC Co

  • m

mp po

  • n

ne en nt t.DEFAULT_ENABLED M My yC Co

  • m

mp po

  • n

ne en nt t.PROP_TOPIC + "=" + M My yC Co

  • m

mp po

  • n

ne en nt t.DEFAULT_TOPIC_1, M My yC Co

  • m

mp po

  • n

ne en nt t.PROP_TOPIC + "=" + M My yC Co

  • m

mp po

  • n

ne en nt t.DEFAULT_TOPIC_2, "service.ranking:Integer=15" }) p pu ub bl li ic c c cl la as ss s M My yC Co

  • m

mp po

  • n

ne en nt t { s st ta at ti ic c f fi in na al l S St tr ri in ng g PROP_ENABLED = "enabled"; s st ta at ti ic c f fi in na al l S St tr ri in ng g PROP_TOPIC = "topic"; s st ta at ti ic c f fi in na al l S St tr ri in ng g PROP_USERNAME = "userName"; s st ta at ti ic c f fi in na al l b bo

  • l

le ea an n DEFAULT_ENABLED = t tr ru ue e; s st ta at ti ic c f fi in na al l S St tr ri in ng g DEFAULT_TOPIC_1 = "topicA"; s st ta at ti ic c f fi in na al l S St tr ri in ng g DEFAULT_TOPIC_2 = "topicB";

24 of 53

slide-25
SLIDE 25

Simplify Component Dvlpmnt

@Activate p pr ro

  • t

te ec ct te ed d v vo

  • i

id d activate(f fi in na al l M Ma ap p config) { f fi in na al l b bo

  • l

le ea an n enabled = P Pr ro

  • p

pe er rt ti ie es sU Ut ti il l.toBoolean(config.g ge et t(PROP_ENABLED), DEFAULT_ENABLED); i if f ( enabled ) { t th hi is s.userName = P Pr ro

  • p

pe er rt ti ie es sU Ut ti il l.toString(config.g ge et t(PROP_USERNAME), n nu ul ll l t th hi is s.topics = P Pr ro

  • p

pe er rt ti ie es sU Ut ti il l.toStringArray(config.g ge et t(PROP_TOPIC), n ne ew w S St tr ri in ng g[] {DEFAULT_TOPIC_1, DEFAULT_TOPIC_2}); } }

25 of 53

slide-26
SLIDE 26

Use annotations for configuration...

@interface M My yC Co

  • n

nf fi ig g { b bo

  • l

le ea an n enabled() d de ef fa au ul lt t t tr ru ue e; S St tr ri in ng g[] topic() d de ef fa au ul lt t {"topicA", "topicB"}; S St tr ri in ng g userName(); i in nt t service_ranking() d de ef fa au ul lt t 15; }

26 of 53

slide-27
SLIDE 27

...and reference them in lifecycle methods

@Component p pu ub bl li ic c c cl la as ss s M My yC Co

  • m

mp po

  • n

ne en nt t { S St tr ri in ng g userName; S St tr ri in ng g[] topics; @Activate p pr ro

  • t

te ec ct te ed d v vo

  • i

id d activate(f fi in na al l M My yC Co

  • n

nf fi ig g config) { // note: annotation MyConfig used as interface i if f ( config.enabled() ) { t th hi is s.userName = config.userName(); t th hi is s.topics = config.topic(); } } }

27 of 53

slide-28
SLIDE 28

...or even simpler...

@Component p pu ub bl li ic c c cl la as ss s M My yC Co

  • m

mp po

  • n

ne en nt t { p pr ri iv va at te e M My yC Co

  • n

nf fi ig g configuration; @Activate p pr ro

  • t

te ec ct te ed d v vo

  • i

id d activate(f fi in na al l M My yC Co

  • n

nf fi ig g config) { // note: annotation MyConfig used as interface i if f ( config.enabled() ) { t th hi is s.configuration = config; } } }

28 of 53

slide-29
SLIDE 29

Annotation Mapping

⦿ Fields registered as component properties ⦿ Name mapping (_ -> .) ⦿ Type conversion for configurations

29 of 53

slide-30
SLIDE 30

Additional Metatype Support (RFC 208)

@ObjectClassDefinition(label="My Component", description="Coolest component in the world.") @interface M My yC Co

  • n

nf fi ig g { @AttributeDefinition(label="Enabled", description="Topic and user name are used if enabled") b bo

  • l

le ea an n enabled() d de ef fa au ul lt t t tr ru ue e; @AttributeDefinition(...) S St tr ri in ng g[] topic() d de ef fa au ul lt t {"topicA", "topicB"}; @AttributeDefinition(...) S St tr ri in ng g userName(); i in nt t service_ranking() d de ef fa au ul lt t 15; // maps to service.ranking }

30 of 53

slide-31
SLIDE 31

RFC 190 - Declarative Services Enhancements

⦿ Annotation configuration support ⦿ Support of prototype scope ⦿ Introspection API ⦿ DTOs

31 of 53

slide-32
SLIDE 32

HTTP Service

32 of 53

slide-33
SLIDE 33

Http Whiteboard Service RFC 189

⦿ Whiteboard support ⦿ Servlet API 3+ Support ⦿ and Introspection API

33 of 53

slide-34
SLIDE 34

Whiteboard Servlet Registration

@Component(service = javax.servlet.S Se er rv vl le et t.c cl la as ss s, scope="PROTOTYPE", p pr ro

  • p

pe er rt ty y={ "osgi.http.whiteboard.servlet.pattern=/products/*", }) p pu ub bl li ic c c cl la as ss s M My yS Se er rv vl le et t e ex xt te en nd ds s H Ht tt tp pS Se er rv vl le et t { ... }

34 of 53

slide-35
SLIDE 35

Whiteboard Servlet Filter Registration

@Component(service = javax.servlet.F Fi il lt te er r.c cl la as ss s, scope="PROTOTYPE", p pr ro

  • p

pe er rt ty y={ "osgi.http.whiteboard.filter.pattern=/products/*", }) p pu ub bl li ic c c cl la as ss s M My yF Fi il lt te er r i im mp pl le em me en nt ts s F Fi il lt te er r { ... }

35 of 53

slide-36
SLIDE 36

Additional Support

⦿ Most listener types are supported Register with their interface ⦿ Error Pages and Resources ⦿ Shared and segregated HttpContexts ⦿ Target Http Service

36 of 53

slide-37
SLIDE 37

Cloud

37 of 53

slide-38
SLIDE 38

Current PaaS offerings...

38 of 53

slide-39
SLIDE 39

OSGi Cloud Ecosystems PaaS

39 of 53

slide-40
SLIDE 40

An OSGi cloud ecosystem...

⦿ Many frameworks

○ hosting a variety of deployments

⦿ Together providing The Application ⦿ Not a bunch of replicas

○ rather a collection of different nodes ○ with different roles working together ○ some may be replicas

⦿ Load varies over time ⦿ ... and so does your cloud system

○ topology ○ configuration ○ number of nodes ○ depending on the demand

40 of 53

slide-41
SLIDE 41

To realize this you need...

⦿ Information!

○ need to know what nodes are available ○ ability to react to changes

⦿ Provisioning capability ⦿ Remote invocation

○ inside your cloud system ○ to get nodes to communicate ○ either directly... ○ ... or as a means to set up communication channels

41 of 53

slide-42
SLIDE 42

RFC 183 - Cloud Ecosystems

F Fr ra am me ew wo

  • r

rk kN No

  • d

de eS St ta at tu us s service:

information about each Cloud node accessible as a Remote Service throughout the ecosystem

Information such as:

Hostname/IP address Location (country etc) OSGi and Java version running A REST management URL Runtime metadata

Available memory / disk space Load measurement

... you can add custom metadata too ...

42 of 53

slide-43
SLIDE 43

FrameworkNodeStatus service properties

43 of 53

slide-44
SLIDE 44

RFC 182 - REST API

A cloud-friendly remote management API works great with FrameworkNodeStatus Example:

addingService(S Se er rv vi ic ce eR Re ef fe er re en nc ce e<F Fr ra am me ew wo

  • r

rk kN No

  • d

de eS St ta at tu us s> r re ef f) { // A new Node became available S St tr ri in ng g url = r re ef f.getProperty("org.osgi.node.rest.url"); R Re es st tC Cl li ie en nt t rc = n ne ew w R Re es st tC Cl li ie en nt t(n ne ew w URI(url)); // Provision the new node rc.installBundle(...); rc.startBundle(...); }

44 of 53

slide-45
SLIDE 45

Additional ideas in RFC 183

⦿ Special Remote Services config type

・ osgi.configtype.ecosystem ・ defines supported Remote Service data types ・ not visible outside of cloud system

⦿ Ability to intercept remote service calls

・ can provide different service for each client ・ can do invocation counting (quotas, billing)

⦿ Providing remote services meta-data

・ quota exceeded ・ payment needed ・ maintenance scheduled

45 of 53

slide-46
SLIDE 46

Current OSGi cloud work

Provides a base line ○ to build fluid cloud systems ○ portability across clouds Where everything is dynamic ○ nodes can be repurposed ... and you deal with your cloud nodes through OSGi services

46 of 53

slide-47
SLIDE 47

Type and Package Annotations

47 of 53

slide-48
SLIDE 48

Semantic Versioning...

... is a versioning policy for exported packages. OSGi versions: <major>.<minor>.<micro>.<qualifier> Updating package versions:

  • fix/patch (no change to API):

update micro

  • extend API (affects implementers, not clients):

update minor

  • API breakage:

update major Note: not always used for bundle versions

48 of 53

slide-49
SLIDE 49

RFC 197 – OSGi Type and Package Annotations

⦿ Annotations for documenting semantic versioning information

⦿ Class retention annotations

⦿ @Version ⦿ @ProviderType ⦿ @ConsumerType

49 of 53

slide-50
SLIDE 50

Other Enterprise Spec updates

50 of 53

slide-51
SLIDE 51

▻ Remote Service Admin 1.1

・ Remote Service registration modification

▻ Subsystems 1.1

・ Provide Deployment Manifest separately ・ Many small enhancements

▻ Portable Java SE/EE Contracts

51 of 53

slide-52
SLIDE 52

Where can I get it?

Core R6 spec released this week:

http://www.osgi.org/Specifications/HomePage (http://www.osgi.org/Specifications/HomePage)

Enterprise R6 draft released this week:

http://www.osgi.org/Specifications/Drafts (http://www.osgi.org/Specifications/Drafts) RFCs 189, 190, 208 included in zip All current RFCs at https://github.com/osgi/design (https://github.com/osgi/design)

52 of 53

slide-53
SLIDE 53

Questions?

53 of 53