Spring-Boot HATEOAS server example

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.4.3.RELEASE</version>
  </parent>

  <groupId>de.mvitz</groupId>
  <artifactId>spring-hateoas-server</artifactId>
  <version>0.1.0-SNAPSHOT</version>

  <properties>
    <java.version>1.8</java.version>
  </properties>

  <dependencies>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-hateoas</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-devtools</artifactId>
      <optional>true</optional>
    </dependency>
  </dependencies>

  <build>
    <finalName>${project.artifactId}</finalName>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>

</project>

Request with MediaType without EnableHypermediaSupport

~/Development/new/spring-hateoas-server $ http -p Hhb :8080/users Accept:application/hal+json
GET /users HTTP/1.1
Accept: application/hal+json
Accept-Encoding: gzip, deflate
Connection: keep-alive
Host: localhost:8080
User-Agent: HTTPie/0.9.8

HTTP/1.1 200
Content-Type: application/hal+json;charset=UTF-8
Date: Wed, 18 Jan 2017 10:52:51 GMT
Transfer-Encoding: chunked

[
    {
        "links": [
            {
                "href": "http://localhost:8080/users/foo",
                "rel": "self"
            }
        ]
    }
]

Response with EnableHypermediaSupport

~/Development/new/spring-hateoas-server $ http -p Hhb :8080/users
GET /users HTTP/1.1
Accept: */*
Accept-Encoding: gzip, deflate
Connection: keep-alive
Host: localhost:8080
User-Agent: HTTPie/0.9.8

HTTP/1.1 200
Content-Type: application/json;charset=UTF-8
Date: Wed, 18 Jan 2017 10:20:50 GMT
Transfer-Encoding: chunked

[
    {
        "_links": {
            "self": {
                "href": "http://localhost:8080/users/foo"
            }
        }
    }
]

Response without EnableHypermediaSupport

~/Development/new/spring-hateoas-server $ http -p Hhb :8080/users
GET /users HTTP/1.1
Accept: */*
Accept-Encoding: gzip, deflate
Connection: keep-alive
Host: localhost:8080
User-Agent: HTTPie/0.9.8

HTTP/1.1 200
Content-Type: application/json;charset=UTF-8
Date: Wed, 18 Jan 2017 10:20:26 GMT
Transfer-Encoding: chunked

[
    {
        "links": [
            {
                "href": "http://localhost:8080/users/foo",
                "rel": "self"
            }
        ]
    }
]

SpringHateoasApplication.java

package de.mvitz.spring.hateoas.server;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.hateoas.ExposesResourceFor;
import org.springframework.hateoas.ResourceSupport;
import org.springframework.hateoas.config.EnableHypermediaSupport;
import org.springframework.hateoas.mvc.ResourceAssemblerSupport;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.Collections;
import java.util.List;

import static org.springframework.hateoas.config.EnableHypermediaSupport.HypermediaType.HAL;

@SpringBootApplication
//@EnableHypermediaSupport(type = HAL)
public class SpringHateoasApplication {

  static class User {
    String name;
    User(String name) { this.name = name; }
  }

  static class UserResource extends ResourceSupport {
    String name;
    public UserResource(User user) { this.name = user.name; }
  }

  static class UserResourceAssembler extends ResourceAssemblerSupport<User, UserResource> {
    public UserResourceAssembler() {
      super(UserController.class, UserResource.class);
    }

    @Override
    protected UserResource instantiateResource(User entity) { return new UserResource(entity); }

    @Override
    public UserResource toResource(User entity) { return createResourceWithId(entity.name, entity); }
  }

  @Controller
  @RequestMapping("/users")
  @ResponseBody
  @ExposesResourceFor(UserResource.class)
  class UserController {
    UserResourceAssembler userResourceAssembler = new UserResourceAssembler();

    @RequestMapping
    public List<UserResource> users() {
      return Collections.singletonList(user("foo"));
    }

    @RequestMapping("/{name}")
    public UserResource user(@PathVariable("name") String name) {
      return userResourceAssembler.toResource(new User(name));
    }
  }

  public static void main(String[] args) {
    SpringApplication.run(SpringHateoasApplication.class, args);
  }
}