Spring Data REST - HAL browser - returning HAL browser HTML rather than root of API

Question

I am having a look into Spring Data REST, specifically the HAL browser. I have been following the documentation at http://docs.spring.io/spring-data/rest/docs/current/reference/html/#_the_hal_browser.

When I navigate to http://localhost:8080 it redirects me (as expected) to http://localhost:8080/browser/index.html#/, and the HAL browser is displayed. My issue is, rather than this page displaying details about the root of my API, it is trying to display itself. For example, the Response Body section has the HTML of the HAL browser in it, not JSON from my API.

I'm not sure if I have done something wrong in my setup - it is pretty vanilla (complete source listing below), so would appreciate any pointers in the right direction!

For completeness - if I enter /users into the Explorer text field and select Go!, then I do see details of my API as expected. Furthermore, if I remove the HAL browser dependency and browse to http://localhost:8080, then I see the root of my API as expected.

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<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>

    <groupId>sample</groupId>
    <artifactId>restsample</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>My application</name>
    <description>My application description</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.4.0.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-rest</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-rest-hal-browser</artifactId>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

Application.java

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

User.java

@Data
@Entity
public class User {
    @Id
    @GeneratedValue
    private Long id;

    @NotBlank
    @Size(min = 1, max = 100)
    @Column(unique = true)
    private String username;
}

UserRepository.java

@RepositoryRestResource
public interface UserRepository extends CrudRepository<User, Long> {
    User save(User user);
}

Thank you for the reply - however even if I add the application/json+hal content type header to the "Custom Request Headers" section of the HAL browser, I still get the HAL browser itself returned as the response. Furthermore, there is absolutely no indication in the documentation that this should be needed (and any examples I have seen of a running HAL browser do not appear to need to pass the content type header either). — user2455157
My mistake, I should have used "Accept: application/hal+json", which does indeed return the correct data. So, I guess the issue is the way that the spring boot package puts the redirect to the HAL browser on the same endpoint as the API, thus by default it won't work as expected. — user2455157

Bablu Bablu · Accepted Answer · 2021-06-12T17:38:58

Try changing dependency from

<dependency>
    <groupId>org.springframework.data</groupId>
    <artifactId>spring-data-rest-hal-browser</artifactId>
</dependency>

to

<dependency>
    <groupId>org.springframework.data</groupId>
    <artifactId>spring-data-rest-hal-explorer</artifactId>
</dependency>

and then goto: http://localhost:8080

Spring Data REST - HAL browser - returning HAL browser HTML rather than root of API

6 Answers