ktor fruit example

00-ktor-fruits-example

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auth-dependencies.gradle

dependencies {
    ...
    implementation "io.ktor:ktor-auth:1.0.0"
}

basic-gradle-setup.gradle

repositories {
    ...
    jcenter()
}
dependencies {
    ...
    implementation "io.ktor:ktor-server-core:1.0.0"
    implementation "io.ktor:ktor-server-netty:1.0.0"
}

cleanup.kt

fun Application.module() {
    installGlobalFeatures()

    val fruitStash = mutableListOf<Fruit>()
    routing {
        ...
    }
}

fun Application.installGlobalFeatures() {
    install(ContentNegotiation) {...}
    install(StatusPages) {...}
    install(Authentication) {...}
}

content-negotiation-dependency.gradle

dependencies {
    ...
    implementation "io.ktor:ktor-jackson:1.0.0"
}

feature-basic-auth.kt

install(Authentication) {
    basic {
        validate { (name, password) ->
            if(name == "lovis" && password == "cc hamburg") { 
                UserIdPrincipal(name)
            } else {
                null
            }
        }
    }
}
...
authenticate {
    post("/fruits") {
        ...
    }
}

feature-content-negotiation.kt

fun Application.module() {
    install(feature = ContentNegotiation) {
        jackson()
    }
    ...
}

feature-status-pages-mapping.kt

exception<IndexOutOfBoundsException> {
    call.respond(NotFound, "404 Not Found")
}

feature-status-pages.kt

fun Application.module() {
    install(ContentNegotiation) {...}
    install(StatusPages) {
        exception<Throwable> { err -> call.respondText { err.message ?: "Unknown Error" } }
    }
    val fruitStash = mutableListOf<Fruit>()
    routing {
        ...
         get("/fruits/{index}") {
            val index = call.parameters["index"]?.toIntOrNull()
            if(index != null) {
                val fruit = fruitStash[index]
                call.respond(fruit)
            } else {
                call.respond(HttpStatusCode.NotFound)
            }
        }
    }
}

get-by-id.kt

fun Application.module() {
    install(ContentNegotiation) {...}
    val fruitStash = mutableListOf<Fruit>()
    routing {
        ...
         get("/fruits/{index}") {
            val index = call.parameters["index"]?.toIntOrNull()
            if(index != null) {
                val fruit = fruitStash[index]
                call.respond(fruit)
            } else {
                call.respond(HttpStatusCode.NotFound)
            }
        }
    }
}

merge-routes.kt

routing {
    route("/fruits") {
        authenticate {
            post { ... }
        }
        get { ... }
        get("/{index}") { ... }
    }
}

routing.kt

fun Application.module() {
    val fruitStash = mutableListOf<String>()
    routing {
        post("/fruits") {
            fruitStash.add(call.receive<String>())
            call.respond(HttpStatusCode.Created)
        }
        get("/fruits") {
            call.respond(fruitStash)
        }
    }
}

simple-main.kt

fun main(args: Array<String>) {
    embeddedServer(
            factory = Netty,
            port = 8080,
            module = Application::module
    ).start(wait = true)
}

simple-module.kt

fun Application.module() {
    routing {
        ...
    }
}

typed-routing.kt

data class Fruit(val name: String)

fun Application.module() {
    val fruitStash = mutableListOf<Fruit>()
    routing {
        post("/fruits") {
            fruitStash.add(call.receive<Fruit>())
            call.respond(Created)
        }
        get("/fruits") {
            call.respond(fruitStash)
        }
    }
}