Back-end using Spring Boot

A java based framework to generate web application back end services

Initialize a service

Get started using spring initializr.

https://start.spring.io

Package Manager: Maven
Language: Java
Spring boot version: 2.5.3
Name <test service>
Dependencies:
- Spring Web
- Spring Data JPA 
- PostgreSQL Driver 

Generate and unpack download file to project location

Open project in IDE (e.g. IntelliJ)
Run
Check in browser

localhost:8080

Add “hello world controller”

add package "controller"
add class "InfoController"

@RestController
public class InfoController  {
     @GetMapping("/")
     public String home() {
        return "This is the backend service for the application Homelab-Docu";
     }
}

Extend InfoController with version information

    @Value("${app.name}")
    private String appName;

    @Value("${app.description}")
    private String appDescription;

    @Value("${app.version}")
    private String appVersion;

    @GetMapping("/version")
    public Object getVersion(HttpServletResponse response){
        Map<String, String> properties = new HashMap<>();
        properties.put("appName", appName);
        properties.put("appDescription", appDescription);
        properties.put("appVersion", appVersion);

        response.addHeader("Access-Control-Allow-Origin", "*");
        response.setStatus(HttpStatus.OK.value());

        return properties;
    }