CODEWITHSUNDEEP
javaspringspring-mvchateoasspring-hateoas
Chad
Chad

Reputation: 2071

Generating consistent resource links in Spring

When producing links using this line of code:

indexResource.add(linkTo(IndexController.class).withSelfRel());

This JSON is produced:

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

However, resource links produced by Spring Data Rest produce this JSON:

{
  "_links" : {
    "self" : {
      "href" : "http://localhost:8080/persons{?page,size,sort}",
      "templated" : true
    }
  }
}

Particularly, I would like to imitate the one produced by Spring Data Rest. How do I go about this?

I am using Spring Boot with the following configuration:

@Configuration
@Import(RepositoryRestMvcConfiguration.class)
@EnableAutoConfiguration
@EnableJpaRepositories(repositoryFactoryBeanClass = EnversRevisionRepositoryFactoryBean.class)
@EnableHypermediaSupport(type = EnableHypermediaSupport.HypermediaType.HAL)
@ComponentScan
public class Application { ... }

Retaining or removing @EnableHypermediaSupport(type = EnableHypermediaSupport.HypermediaType.HAL) doesn't seem to change anything.

I also have the following gradle dependencies:

compile "org.springframework.boot:spring-boot-starter-data-rest"
compile "org.springframework.boot:spring-boot-starter-data-jpa"
compile "org.springframework.boot:spring-boot-starter-actuator"
compile "org.springframework.boot:spring-boot-starter-jetty"
compile "org.springframework.data:spring-data-envers:0.2.0.RELEASE"
compile "org.hibernate:hibernate-envers:4.3.6.Final"
runtime "mysql:mysql-connector-java:5.1.32"
testCompile "junit:junit"

Upvotes: 2

Views: 1195

Answers (4)

mlo55
mlo55

Reputation: 6915

If you make the request with the following request header

Accept: application/alps+json

You should get the desired result, of...

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

If you make the request with:

Accept: application/json

or

Accept: application/hal+json

Then you'll get the HAL (currently the default, see link below)

{
  "_links" : {
    "self" : {
      "href" : "http://localhost:8080/persons{?page,size,sort}",
      "templated" : true
    }
  }
}

See https://github.com/spring-projects/spring-hateoas/blob/master/src/main/java/org/springframework/hateoas/config/EnableHypermediaSupport.java

Upvotes: 0

David Caseria
David Caseria

Reputation: 261

In order to produce the HAL formatted JSON, your HTTP request must accept application/hal+json (i.e. the Accept header is application/hal+json).

The default content type of your application may also be application/json. You can change the default content type to application/hal+json through the following configuration class:

public class WebConfig extends WebMvcConfigurerAdapter {
    @Override
    public void configureContentNegotiation(ContentNegotiationConfigurer c) {
        c.defaultContentType(MediaTypes.HAL_JSON);
    }
}

Upvotes: 1

a better oliver
a better oliver

Reputation: 26828

Spring Data Rest uses the HAL format. It should be the default for newer versions of Spring HATEOAS. You can activate it with an annotation on a Configuration class:

@EnableHypermediaSupport(type= {HypermediaType.HAL})

UPDATE

I ran into a similar siutation with Spring Boot. I had to add the following to my my pom.xml:

<dependency>
  <groupId>org.springframework.plugin</groupId>
  <artifactId>spring-plugin-core</artifactId>
  <version>1.1.0.RELEASE</version>
</dependency>

Upvotes: 1

pd30
pd30

Reputation: 240

I would suggest creating two classes like Link and Self.Link has Self. Self has href and templated. Create a class that does the formation of links as Java object. Then use a Java to Json library like GSON for a similar output as above

Upvotes: 0

Related Questions