extractMethod

Signature

def extractMethod: Directive1[HttpMethod]

Description

Extracts the HttpMethod from the request context and provides it for use for other directives explicitly.

Example

In the below example our route first matches all GET requests, and if an incoming request wasn’t a GET, the matching continues and the extractMethod route will be applied which we can use to programatically print what type of request it was - independent of what actual HttpMethod it was:

Scala
Java
sourceval route =
  concat(
    get {
      complete("This is a GET request.")
    },
    extractMethod { method =>
      complete(s"This ${method.name} request, clearly is not a GET!")
    })

// tests:
Get("/") ~> route ~> check {
  responseAs[String] shouldEqual "This is a GET request."
}

Put("/") ~> route ~> check {
  responseAs[String] shouldEqual "This PUT request, clearly is not a GET!"
}
Head("/") ~> route ~> check {
  responseAs[String] shouldEqual "This HEAD request, clearly is not a GET!"
}
sourceimport static org.apache.pekko.http.javadsl.server.Directives.complete;
import static org.apache.pekko.http.javadsl.server.Directives.get;
import static org.apache.pekko.http.javadsl.server.Directives.extractMethod;


final Route route =
    concat(
        get(() -> complete("This is a GET request.")),
        extractMethod(
            method -> complete("This " + method.value() + " request, clearly is not a GET!")));

testRoute(route).run(HttpRequest.GET("/")).assertEntity("This is a GET request.");

testRoute(route)
    .run(HttpRequest.PUT("/").withEntity("put content"))
    .assertEntity("This PUT request, clearly is not a GET!");

testRoute(route)
    .run(HttpRequest.HEAD("/"))
    .assertEntity("This HEAD request, clearly is not a GET!");

Custom Http Method

When you define a custom HttpMethod, you can define a route using extractMethod.

Scala
Java
sourceimport org.apache.pekko.http.scaladsl.settings.{ ParserSettings, ServerSettings }

// define custom method type:
val BOLT = HttpMethod.custom("BOLT", safe = false,
  idempotent = true, requestEntityAcceptance = Expected)

// add custom method to parser settings:
val parserSettings = ParserSettings.forServer(system).withCustomMethods(BOLT)
val serverSettings = ServerSettings(system).withParserSettings(parserSettings)

val routes = extractMethod { method =>
  complete(s"This is a ${method.name} method request.")
}
val binding = Http().newServerAt(host, port).withSettings(serverSettings).bind(routes)

val request = HttpRequest(BOLT, s"http://$host:$port/", protocol = `HTTP/1.1`)
sourceimport static org.apache.pekko.http.javadsl.server.Directives.complete;
import static org.apache.pekko.http.javadsl.server.Directives.extractMethod;


// define custom method type:
HttpMethod BOLT = HttpMethods.custom("BOLT", false, true, Expected);

// add custom method to parser settings:
final ParserSettings parserSettings = ParserSettings.forServer(system).withCustomMethods(BOLT);
final ServerSettings serverSettings =
    ServerSettings.create(system).withParserSettings(parserSettings);

final Route routes =
    concat(extractMethod(method -> complete("This is a " + method.name() + " request.")));
final Http http = Http.get(system);
final CompletionStage<ServerBinding> binding =
    http.newServerAt(host, port)
        .withSettings(serverSettings)
        .logTo(loggingAdapter)
        .bind(routes);

HttpRequest request =
    HttpRequest.create()
        .withUri("http://" + host + ":" + Integer.toString(port))
        .withMethod(BOLT)
        .withProtocol(HTTP_1_1);

CompletionStage<HttpResponse> response = http.singleRequest(request);
1.0.1