headerValueByName

Signature

def headerValueByName(headerName: Symbol): Directive1[String] 
def headerValueByName(headerName: String): Directive1[String] 

Description

Extracts the value of the HTTP request header with the given name.

If no header with a matching name 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 optionalHeaderValueByName directive instead.

Example

Scala
sourceval route =
  headerValueByName("X-User-Id") { userId =>
    complete(s"The user is $userId")
  }

// tests:
Get("/") ~> RawHeader("X-User-Id", "Joe42") ~> route ~> check {
  responseAs[String] shouldEqual "The user is Joe42"
}

Get("/") ~> Route.seal(route) ~> check {
  status shouldEqual BadRequest
  responseAs[String] shouldEqual "Request is missing required HTTP header 'X-User-Id'"
}
Java
sourceimport static org.apache.pekko.http.javadsl.server.Directives.complete;
import static org.apache.pekko.http.javadsl.server.Directives.headerValueByName;

final Route route = headerValueByName("X-User-Id", userId -> complete("The user is " + userId));

// tests:
final RawHeader header = RawHeader.create("X-User-Id", "Joe42");
testRoute(route).run(HttpRequest.GET("/").addHeader(header)).assertEntity("The user is Joe42");

testRoute(route)
    .run(HttpRequest.GET("/"))
    .assertStatusCode(StatusCodes.BAD_REQUEST)
    .assertEntity("Request is missing required HTTP header 'X-User-Id'");