Getting Started with GraphQL Netflix DGS

Prereq

• Gradle
• Java 17 (Could work for other versions of Java)

Create Spring Boot Project

Add the?Spring Initializr?plugin on IntelliJ

On IntelliJ goto?file?->?new

Set

• Language: Java
• Type: Gradle-Grooby
• JDK: 17
• Java: 17
• Package: Jar

Then click?Next

The only dependency you will need is?Spring Web

Click?Create, now you created a Spring Boot Project

Add GraphQL DGS

In build.gradle add the plugin?id "com.netflix.dgs.codegen" version "4.4.3"?change the?org.springframework.boot?version to?2.4.4

add the dependencies

implementation(platform("com.netflix.graphql.dgs:graphql-dgs-platform-dependencies:3.10.2"))
implementation "com.netflix.graphql.dgs:graphql-dgs-spring-boot-starter"        

build.gradle sample

plugins {
    id 'java'
    id 'org.springframework.boot' version '2.4.4'
    id 'io.spring.dependency-management' version '1.1.0'
    id "com.netflix.dgs.codegen" version "4.4.3"
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '17'

repositories {
    mavenCentral()
}

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
        implementation(platform('com.netflix.graphql.dgs:graphql-dgs-platform-dependencies:3.10.2'))
    implementation 'com.netflix.graphql.dgs:graphql-dgs-spring-boot-starter'
}

tasks.named('test') {
    useJUnitPlatform()
}        

Add GraphQL Schema

Create a directory in?resources?called?schema. Create a file called?schema.graphqls?under?schema?directory.

src/main/resources/schema/schema.graphqls

type Query {
    shows(titleFilter: String): [Show]
}

type Show {
    title: String
    releaseYear: Int
}        

Add DataFetcher

In the same directory as your application class add the following file

ShowsDataFetcher.java

@DgsComponent
public class ShowsDatafetcher {

    private final List<Show> shows = List.of(
            new Show("Stranger Things", 2016),
            new Show("Ozark", 2017),
            new Show("The Crown", 2016),
            new Show("Dead to Me", 2019),
            new Show("Orange is the New Black", 2013)
    );

    @DgsQuery
    public List<Show> shows(@InputArgument String titleFilter) {
        if(titleFilter == null) {
            return shows;
        }

        return shows.stream().filter(s -> s.getTitle().contains(titleFilter)).collect(Collectors.toList());
    }
}        

Generate the Show Type with the following command.

./gradlew generateJava        

Import your dependencies

Refresh Gradle

And import all your classes.

Spin up your GraphQL DGS App

To spin up your app run

./gradlew bootRun        

Run GraphQL Query

Go to http:localhost:8080/graphiql

and run the following query

query {
  shows {
    title
    releaseYear
  }
}        

Happy Developing! ??

Link to the GitHub Repo