failWith
Description
Bubbles up the given error through the route structure where it is dealt with by the closest handleExceptions
directive and its ExceptionHandler
ExceptionHandler
.
failWith
explicitly raises an exception that gets bubbled up through the route structure to be picked up by the nearest handleExceptions
directive. Using failWith
rather than simply throwing an exception enables the route structure’s Exception Handling mechanism to deal with the exception even if the current route is executed asynchronously on another thread (e.g. in a Future
or separate actor).
If no handleExceptions
is present above the respective location in the route structure the top-level routing logic will handle the exception and translate it into a corresponding HttpResponse
HttpResponse
using the in-scope ExceptionHandler
ExceptionHandler
. See the Exception Handling chapter for more details.
There is one notable special case: If the given exception is a RejectionError
RejectionError
exception it is not bubbled up, but rather the wrapped exception is unpacked and “executed”. This allows the “tunneling” of a rejection via an exception.
Example
- Scala
-
source
val route = path("foo") { failWith(new RuntimeException("Oops.")) } // tests: Get("/foo") ~> Route.seal(route) ~> check { status shouldEqual StatusCodes.InternalServerError responseAs[String] shouldEqual "There was an internal server error." }
- Java
-
source
import static akka.http.javadsl.server.Directives.failWith; import static akka.http.javadsl.server.Directives.path; final Route route = path("foo", () -> failWith(new RuntimeException("Oops.")) ); // tests: testRoute(route).run(HttpRequest.GET("/foo")) .assertStatusCode(StatusCodes.INTERNAL_SERVER_ERROR) .assertEntity("There was an internal server error.");