Loom

A minimalistic Kotlin web framework.

Get started

Maven

<dependency>
    <groupId>dk.magical</groupId>
    <artifactId>Loom</artifactId>
    <version>LATEST</version>
</dependency>

Loom

The Loom framework use threads from the ExecutorService.
Use the Executors static creator methods to easily provide the ExecutorService.

Example:

val loom = Loom(Executors.newCachedThreadPool())

Routers

The Router take a base URL in the constructor.

Example:

val router = Router("/users")

Make Loom use the router:

loom.route(router)

Methods

Loom support the methods: GET, POST, PUT, DELETE

router.get("/") { request, response -> }

router.post("/") { request, response -> }

router.put("/") { request, response -> }

router.delete("/") { request, response -> }

URL

val router = Router("/users")

router.get("/name")

Will catch the GET requests send to: "/users/name"

URL-parameters

val router = Router("/users")

router.get("/name/{name}")

Will catch the GET requests send to: "/users/name/name" Where name match everything.

The URL-parameters chan be accessed in the handler using the request:

router.get("/name/{name}") { request, response ->
    val name = request.urlParameters["name"]
}

Request

The request contains the properties:

• method: The request method, ex: GET, POST
• urlParameters: Values from the URL, ex: /users/name/{name}, {name} defines the name url parameter.
• queryParameters: Query parameters, ex: /users?name=Peter
• headers: The key value headers
• body: The optional request body

val method = request.method
val urlName = request.urlParameters["name"]
val queryName = request.queryParameters["name"]
val headerName = request.headers["name"]
val body = request.body

Response

The response have the methods:

• status: Set the response http-status.
• header: Add the header to the response.
• headers: Add multiple headers to the response.
• body: Set the response body.
• end: Send the response.

response.status(Status.OK).header("name", "Peter").body("Body").end()

Middleware

Middleware will catch a request before a Router.
More than one Middleware can catch the same request, they will be called in the order they are added to the Loom server.

In this example the first Middleware i called and because the next function i called the second Middleware will be called afterwards. The Router will not be called because the Second Middleware respond before the router is called.

// First middleware
loom.use(HttpMethod.GET, HttpMethod.POST, path = "/users/name") { request, response, next ->
    next()
}

// Second middleware
loom.use(HttpMethod.GET, HttpMethod.POST, path = "/users/name") { request, response, next ->
    response.status(Status.OK).body("Result").end()
}

Next

When the next callback is called the next Middleware will be called if it is the last Middleware the Router will be called.

loom.use(HttpMethod.GET, HttpMethod.POST, path = "/users/name") { request, response, next ->
    next()
}