RESTful API Hello World with Spring Boot

Reference

1. Spring Microservices in Action, Manning, 2017 Jun, https://www.manning.com/books/spring-microservices-in-action
2. Getting Started · Building a RESTful Web Service, https://spring.io/guides/gs/rest-service/

Environment

• Maven: 3.5.2
• JDK: 1.8.0_131, vendor: Oracle Corporation
• OS: "windows 10"
• IDE Spring Tool Suite 3.9.4.RELEASE

1. Create the Maven project

https://start.spring.io/

• Maven project with Java and Spring Boot: 1.5.13 (failure to start) 1.5.10
• Group: com.wonderland.api
• Artifact: helloworld-service
• Dependencies:
• Actuator #for the metric later
• Web
• Rest Repositories
• Eureka Discovery #for the API registration and discover later

Download: helloworld-api.zip
Unzip into {project folder}
Import into IDE: File > Import > Existing Maven Projects > {project folder} > Finish

2. Change the Code

2.1. Add class Greeting with attribute name #force the JSON response with Object return

2.2. Add class HelloworldController with @RestController
2.2.1. Add method:
@RequestMapping(value = "/hello", method = RequestMethod.GET)
public Greeting greeting(@RequestParam(value = "name", defaultValue = "World") String name)

2.3. Update class HelloworldApiApplication with @EnableEurekaClient

3. Configure the Spring Boot application

Edit application.yml (rename the application.properties into application.yml)

spring: 
    application:
        name: helloworld-api

server:
    port: 10010

logging:
    level:
        com.wonderland.api.helloworldapi: DEBUG

management:
    security:
        enabled: false

eureka:     
    instance:
        leaseRenewalIntervalInSeconds: 5
        leaseExpirationDurationInSeconds: 2
    client:
        serviceUrl:
            defaultZone: http://localhost:30100/eureka/

4. Test the API

#> {project folder}\mvn spring-boot:run
http://localhost:10010/hello

http://localhost:10010/hello?name=julian

4.1. Expected error about Eureka registration #to be resolved