headerValueByType

def headerValueByType[T <: HttpHeader: ClassTag](): Directive1[T]

Description

Traverses the list of request headers and extracts the first header of the given type.

The headerValueByType directive finds a header of the given type in the list of request header. If no header of the given type is found the request is rejected with a MissingHeaderRejectionMissingHeaderRejection.

If the header is expected to be missing in some cases or to customize handling when the header is missing use the optionalHeaderValueByType directive instead.

Example

Scala

copysourceval route =
  headerValueByType(Origin) { origin =>
    complete(s"The first origin was ${origin.origins.head}")
  }

val originHeader = Origin(HttpOrigin("http://localhost:8080"))

// tests:
// extract a header if the type is matching
Get("abc") ~> originHeader ~> route ~> check {
  responseAs[String] shouldEqual "The first origin was http://localhost:8080"
}

// reject a request if no header of the given type is present
Get("abc") ~> route ~> check {
  inside(rejection) { case MissingHeaderRejection("Origin") => }
}

Java

copysourceimport static org.apache.pekko.http.javadsl.server.Directives.complete;
import static org.apache.pekko.http.javadsl.server.Directives.headerValueByType;

final Route route =
    headerValueByType(
        Origin.class,
        origin -> complete("The first origin was " + origin.getOrigins().iterator().next()));

// tests:
final Host host = Host.create("localhost", 8080);
final Origin originHeader = Origin.create(HttpOrigin.create("http", host));

testRoute(route)
    .run(HttpRequest.GET("abc").addHeader(originHeader))
    .assertEntity("The first origin was http://localhost:8080");

testRoute(route)
    .run(HttpRequest.GET("abc"))
    .assertStatusCode(StatusCodes.BAD_REQUEST)
    .assertEntity("Request is missing required HTTP header 'Origin'");