Ktor Tutorial

We will be using the Ktor intellij plugin to setup a fully functional GraphQL & Ktor server.

Project Setup

The very first thing we'll be doing is creating a new IntelliJ project and use the Ktor template.

After this we'll press "Next" and fill out the necessary information and then press "Finish". Now we have a brand new Ktor project.

Dependencies

Now we can begin adding the needed dependencies.

Kotlin Gradle ScriptGradle

dependencies {
    implementation("de.stuebingerb:kgraphql:${KGraphQLVersion}")
    implementation("de.stuebingerb:kgraphql-ktor:${KGraphQLVersion}")
}

dependencies {
    implementation "de.stuebingerb:kgraphql:${KGraphQLVersion}"
    implementation "de.stuebingerb:kgraphql-ktor:${KGraphQLVersion}"
}

GraphQL Feature

The only thing left is installing the GraphQL feature onto our server by opening src/Application.kt and use the following lines as the Application.module function.

Application.kt

fun Application.module(testing: Boolean = false) {
    install(GraphQL) {
        configureRouting()
        playground = true
        schema {
            query("hello") {
                resolver { -> "World" }
            }
        }
    }
}

Now we have a fully functional GraphQL Server and we can startup our server by pressing the green play icon beside the main function.

Validating the Setup

We can test out our server by going to localhost:8080/graphql and our hello query should work by providing this query to the GraphQL Playground.

A great place to learn more is following the Star Wars tutorial. Everything mentioned in this tutorial can be placed inside the schema {} block.