1. Building Services with WSO2
Microservices Framework for
Java and WSO2 Application
Server
Kasun Gajasinghe & Kishanthan Thangarajah
WSO2

2. Agenda
• Introduction to Microservices Architecture
• Introduction to WSO2 MSF4J
– Hands-on Sessions
• Introduction to Kubernetes/Docker
• Demonstrating MSF4J deployment with Kubernetes
• Introduction to WSO2 Application Server
– Hands-on Session

3. Microservices Architecture
A method of developing software applications as a
suite of independently deployable, small, modular
services in which each service runs a unique process
and communicates through a well-defined,
lightweight mechanism to serve a business goal.

4. Microservices
http://martinfowler.com/articles/microservices.html

5. Inner & Outer Architecture
http://blogs.gartner.com/gary-olliffe/2015/01/30/microservices-guts-on-the-outside/

6. WSO2 Microservices Framework for Java (MSF4J)
• Lightweight & fast runtime
• Use Java annotations as a way of defining microservices APIs as well
as metrics
• Support well known & widely used methods such as JAX-RS
annotations
• Provide simple ways to develop & deploy microservices
• Built-in Metrics & Analytics APIs with out-of-the-box integration with
WSO2 Data Analytics Server (DAS)
• To be used in the WSO2 platform as a way of replacing all admin
services as well as defining other microservices for inter-component
interactions

7. MSF4J Implementation
• Based on the new WSO2 Carbon 5.0 kernel
• Transport is based on Netty 4.0
• Supports streaming
• High performance
• 5MB pack size
• Starts within 300ms
• ~25MB memory consumption for the framework

8. MSF4J Performance Comparison

9. MSF4J Memory Consumption Comparison

10. Core Features of MSF4J
• Quick & simple development model using simple annotations
• Lightweight & high performance
• Custom interceptors
• OAuth based security
• Metrics gathering & publishing
• Streaming input & streaming output support
• WSO2 DevStudio based tooling for generating microservices projects
starting from a Swagger API definition
• Comprehensive samples demonstrating how to develop microservices
application

11. MSF4J Flow & Thread Model

12. Developer Experience & Programming
Model

13. Development Model
• Maven Archetype
• IDE/Build Classpath (msf4j-all.jar)
• Tooling (Swagger -> Code)

14. Maven pom.xml

15. Maven Archetype
mvn archetype:generate
-DarchetypeGroupId=org.wso2.msf4j
-DarchetypeArtifactId=msf4j-microservice
-DarchetypeVersion=1.0.0
-DgroupId=org.example
-DartifactId=myservice
-Dversion=1.0.0-SNAPSHOT
-Dpackage=org.example.service

16. Example - StockQuote Microservice

17. Application - Main Class

18. Build and Run !!!
mvn clean install
java -jar stockquote-1.0.0.jar

19. Tooling - WSO2 Developer Studio

20. Types of Deployment
• Standalone, Self contained jar files
• OS / Container images

21. Analytics & Monitoring
Supports annotations
• Timed – measures execution
• Metered – measures rate of events
• Counted – counts the total invocations
• HTTPMonitored – monitors HTTP requests

22. Analytics & Monitoring

23. Service Metrics - Console Output

25. Security
• Security is done via a central server issuing JWT or
OAuth tokens.
• The OAuth2SecurityInterceptor verifies the token
before accessing the resources.

26. MSF4J Hands-on Sessions

27. Hello World!
1. Build the sample - wso2msf4j-dist-1.0.0
/samples/helloworld
mvn clean install
2. Run the sample
java -jar helloworld-*.jar
3. Test the sample
curl http://localhost:8080/hello/wso2

28. Generate a sample with Maven
archetype
mvn archetype:generate -
DarchetypeGroupId=org.wso2.msf4j -
DarchetypeArtifactId=msf4j-microservice
-DarchetypeVersion=1.0.0

29. Hands-on - Write a StudentService
• API -
– GET /student/getAll - get all students
– GET /student/get/{id} - get student with {id}
– POST /add - add a student
• Intercept requests
• Monitoring

30. Service class annotations
• JAX-RS HTTP resource methods - @GET @POST
@PUT @DELETE
• Content-negotiation - @Produces @Consumes
• Service lifecycle - @PreDestroy
@PostDestroy

31. HTTP Monitoring with Data Analytics
Server
1. Refer the sample -
wso2msf4j-1.0.0/samples/metrics-
httpmon/metrics-httpmon-fatjar

32. Production Deployment with
Kubernetes and Docker

33. Virtual Machines vs Containers

34. What is Docker
• Container Virtualization
• Build, pack, ship and run applications as containers
• Build once, run in many places
• Isolated

35. Docker Filesystem

36. StockQuote Service Dockerfile

37. Kubernetes
• Kubernetes is an open source orchestration system
for Docker containers
• Docker -> Container lifecycle management
• Kubernetes -> Orchestration and container cluster
management
“Kubernetes, I need 5 Tomcat and one
MySQL server running at all times.”

38. Kubernetes in a Nutshell

39. Kubernetes UI

40. PetStore sample

41. Petstore sample

42. Petstore sample

43. Petstore sample - deployment view

44. Demo - Petstore

45. Building Services with
WSO2 Application Server

46. Current status of Application Server
• Latest release - AS 5.3.0
• Built on top of WSO2 Carbon
• Embedded Apache Tomcat 7 and Apache TomEE 7
• First class support for
– JAX-WS and JAX-RS services
– JavaEE 6 Web Profile applications

47. Future plan for Application Server
• Upcoming release - AS 6.0
• NOT based on WSO2 Carbon or OSGi!
• Built on top of Apache Tomcat

48. AS 6.0
• HTTP Request Monitoring for Tomcat
• Seamless integration with WSO2 Identity Server for
SAML SSO Authentication
• Classloading improvements
Upcoming
- Integration with WSO2 API Manager for exposing
APIs. (API Everywhere!)

49. Hands-on Session

50. Questions?

51. Thank You