What is a default rejection for http methods not found?

What is a default rejection for http methods not found?

This topic is based on a conversation between an anonymous user of Akka and our “Ask AI about Akka” bot in the documentation.

In Akka HTTP, if an HTTP request does not match any defined route, a default 404 Not Found response is returned. However, if a request is filtered based on its HTTP method and it does not match the specified method, it is rejected with a MethodRejection. This MethodRejection is then translated into a 405 Method Not Allowed response by the default RejectionHandler.

Here is an example from the Akka HTTP documentation:

Scala:

val route = method(HttpMethods.PUT) { complete("This is a PUT request.") }

// tests:
Put("/", "put content") ~> route ~> check {
  responseAs[String] shouldEqual "This is a PUT request."
}

Get("/") ~> Route.seal(route) ~> check {
  status shouldEqual StatusCodes.MethodNotAllowed
  responseAs[String] shouldEqual "HTTP method not allowed, supported methods: PUT"
}

Java:

import static akka.http.javadsl.server.Directives.complete;
import static akka.http.javadsl.server.Directives.method;

final Route route = method(HttpMethods.PUT,
    () -> complete("This is a PUT request."));

testRoute(route).run(HttpRequest.PUT("/").withEntity("put content"))
    .assertEntity("This is a PUT request.");

testRoute(route).run(HttpRequest.GET("/")).assertStatusCode(
    StatusCodes.METHOD_NOT_ALLOWED);

In these examples, the route only accepts PUT requests. If a GET request is made, it is rejected and a 405 Method Not Allowed response is returned.

Sources: