Microservices Example

This project based on SERVLET STACK and using Spring Boot 2.0.4.RELEASE and Spring Cloud Finchley.RELEASE

• Service Discovery
• Api Gateway
• User Service Consumer
• User Service Producer
• Spring Boot Admin

Service Discovery

Service discovery is the automatic detection of devices and services offered by these devices on a computer network.

Tech Stack

- Netflix Eureka Server

Build

mvn clean install

Running

mvn spring-boot:run

server is running on port 8761

Api Gateway

The wrapper of services

Tech Stack

- Netflix Zuul Proxy
- OAuth2 Server (JDBC for client detail & Redis for store token)
- Api Documentation (Swagger)

Build

mvn clean install

Running

mvn spring-boot:run

server is running on port 9000

Swagger UI URL = http://localhost:9000/swagger-ui.html swagger resource is manually added on SwaggerConfig.java

User Service Consumer

Consume service from producer using load balancer, monitoring service usage on Hystrix Dashboard, Circuit Breaker when producer is down

Tech Stack

- Ribbon Load balancer (Rest Template & Open Feign)
- Hystrix Dashboard
- Circuit Breaker with fallback method
- Cache service (ehcache)
- Swagger Resource

Build

mvn clean install

Running

mvn spring-boot:run

server is running on port 9999

Hystrix Dashboard URL = http://localhost:9999/hystrix
Hystrix Stream URL = http://localhost:9999/actuator/hystrix.stream

User Service Producer

The main service that connected to database for transfering data

Tech Stack

- Mongo DB
- Mongo Repository like a JPA

Build

mvn clean install

Running

mvn spring-boot:run

server is running on port 9998

Spring Boot Admin

Monitoring your microservice

Tech Stack

- Spring Boot Admin

Build

mvn clean install

Running

mvn spring-boot:run

server is running on port 9995

Spring Boot Admin URL = http://localhost:9995
spring boot admin connect to eureka server and using instance service from eureka server

Consume From Client (Web and Mobile)

Header Authorization: Bearer token must be included in any request

Get Token

Request

Http Method : POST
URL : http://localhost:9000/oauth/token 
Header : Authorization: Basic auth, Content-Type: application/x-www-form-urlencoded
Body : grant_type: client_credentials

Response

{
    "access_token": "c4472fb0-3401-42fe-91c2-65e5627455ed",
    "token_type": "bearer",
    "expires_in": 286,
    "scope": "read write"
}

Access Services (Example)

Http Method : GET
Header : Authorization: Bearer c4472fb0-3401-42fe-91c2-65e5627455ed
URL: http://localhost:9000/api/user-service/getall

• localhost:9000 is host api gateway
• /api/user-service is path between api gateway and user service consumer
• /getall is path from user service consumer
• Header from response get token