1. Evolution of Application Development
From apps, services and APIs to microservices
Kishanthan Thangarajah Afkham Azeez
Tech Lead Snr. Director, Platform Architecture
May 24, 2017

2. Agenda
We will talk about;
● Network connected programs
● Web Applications
● Services
● APIs
● Microservices
2

3. Standalone
Program

4. 4https://github.com/afkham/jaffna-meetup-2017/tree/master/echo-server/src

5. What are the problems in this approach?
● Concurrency handling
● Scaling
● Efficient management of resources
● Everything you need has to be written from scratch every time
● No server environment
● No standards
5

7. Applications

8. Application Servers to the Rescue!
8

9. Echo Web Application
9
https://github.com/afkham/jaffna-meetup-2017/tree/master/echo-app

10. ● Developer only need to focus on the business logic
● All complexities are now handled at the application server layer
○ Concurrency
○ Standards (HTTP)
○ Resource management (memory)
● Easy to port applications from one server to another
Advantages of Applications over Standalone
Programs
10

11. Services

12. What is a Service?
A software functionality or a set of software
functionalities (such as the retrieval of specified
information or the execution of a set of operations)
with a purpose that can be reused by different clients
for different purposes

13. ● Services are well-defined, self-contained.
● Serve as a contract between the service consumer and service
provider.
● Ability to discover and consume services is the fundamental of
SOA (Service Oriented Architecture) level.
Why do we need services?
13

14. Echo Service
14
https://github.com/afkham/jaffna-meetup-2017/tree/master/echo-service

15. APIs

16. ● Standard way to secure and manage API endpoints.
● External consumers / developers interact with your system using
the API’s exposed.
● Mainly we need security, analytics and monetization with API’s
● Other requirements such as throttling, caching, etc are also
needed.
Why do we need APIs?
16

17. Echo API
● Demo - Expose the previously created service as an API in WSO2
API Manager
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18. Microservices
Architecture (MSA)

19. What is MSA?
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.
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20. 20

21. Characteristics of
MSA

22. Small
22
How small?
You build it, you
run it.

23. Organized around Business Capabilities

24. Componentization via Services
● Micro services will use libraries, but their primary
way of componentizing their own software is by
breaking down into services.
● Use explicit component interface during
communication.
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25. Decentralized Data Management

26. Support for Technology Heterogeneity

27. Design for Failure

28. Disposable

29. Microservices
Framework for Java
(MSF4J)

30. What is MSF4J?
A lightweight, high performance
framework for building microservices
in Java
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31. What does it provide?
● Lightweight & fast runtime
● Uses Java annotations as a way of defining microservices
APIs as well as metrics
● Supports well known & widely used methods such as JAXRS
annotations
● Provides simple ways to develop & deploy microservices
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32. Performance
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33. Try it out
● Get the latest release from
https://github.com/wso2/msf4j/releases
● Start with the “Getting started guide”
● A good place to start is the samples
https://github.com/wso2/msf4j/tree/master/sampl
es 33

34. Pet Store Sample
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35. THANK YOU
wso2.com