authenticateOrRejectWithChallenge

Signature

type AuthenticationResult[+T] = Either[HttpChallenge, T]
def authenticateOrRejectWithChallenge[T](authenticator: Option[HttpCredentials] ⇒ Future[AuthenticationResult[T]]): AuthenticationDirective[T]

Description

Lifts an authenticator function into a directive.

This directive allows implementing the low level challenge-response type of authentication that some services may require.

More details about challenge-response authentication are available in the RFC 2617, RFC 7616 and RFC 7617.

Example

Scala
val challenge = HttpChallenge("MyAuth", Some("MyRealm"))

// your custom authentication logic:
def auth(creds: HttpCredentials): Boolean = true

def myUserPassAuthenticator(credentials: Option[HttpCredentials]): Future[AuthenticationResult[String]] =
  Future {
    credentials match {
      case Some(creds) if auth(creds) => Right("some-user-name-from-creds")
      case _                          => Left(challenge)
    }
  }

val route =
  Route.seal {
    path("secured") {
      authenticateOrRejectWithChallenge(myUserPassAuthenticator _) { userName =>
        complete("Authenticated!")
      }
    }
  }

// tests:
Get("/secured") ~> route ~> check {
  status shouldEqual StatusCodes.Unauthorized
  responseAs[String] shouldEqual "The resource requires authentication, which was not supplied with the request"
  header[`WWW-Authenticate`].get.challenges.head shouldEqual HttpChallenge("MyAuth", Some("MyRealm"))
}

val validCredentials = BasicHttpCredentials("John", "p4ssw0rd")
Get("/secured") ~> addCredentials(validCredentials) ~> // adds Authorization header
  route ~> check {
    status shouldEqual StatusCodes.OK
    responseAs[String] shouldEqual "Authenticated!"
  }
Java
final HttpChallenge challenge = HttpChallenge.create("MyAuth", new Option.Some<>("MyRealm"));

// your custom authentication logic:
final Function<HttpCredentials, Boolean> auth = credentials -> true;

final Function<Optional<HttpCredentials>, CompletionStage<Either<HttpChallenge, String>>> myUserPassAuthenticator =
  opt -> {
    if (opt.isPresent() && auth.apply(opt.get())) {
      return CompletableFuture.completedFuture(Right.apply("some-user-name-from-creds"));
    } else {
      return CompletableFuture.completedFuture(Left.apply(challenge));
    }
  };

final Route route = path("secured", () ->
  authenticateOrRejectWithChallenge(myUserPassAuthenticator, userName ->
    complete("Authenticated!")
  )
).seal(system(), materializer());

// tests:
testRoute(route).run(HttpRequest.GET("/secured"))
  .assertStatusCode(StatusCodes.UNAUTHORIZED)
  .assertEntity("The resource requires authentication, which was not supplied with the request")
  .assertHeaderExists("WWW-Authenticate", "MyAuth realm=\"MyRealm\"");

final HttpCredentials validCredentials =
  BasicHttpCredentials.createBasicHttpCredentials("John", "p4ssw0rd");
testRoute(route).run(HttpRequest.GET("/secured").addCredentials(validCredentials))
  .assertStatusCode(StatusCodes.OK)
  .assertEntity("Authenticated!");
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