handleExceptions

Signature

def handleExceptions(handler: ExceptionHandler): Directive0

Description

Catches exceptions thrown by the inner route and handles them using the specified ExceptionHandler.

Using this directive is an alternative to using a global implicitly defined ExceptionHandler that applies to the complete route.

See Exception Handling for general information about options for handling exceptions.

Example

Scala
Java
sourceval divByZeroHandler = ExceptionHandler {
  case _: ArithmeticException => complete(StatusCodes.BadRequest, "You've got your arithmetic wrong, fool!")
}
val route =
  path("divide" / IntNumber / IntNumber) { (a, b) =>
    handleExceptions(divByZeroHandler) {
      complete(s"The result is ${a / b}")
    }
  }

// tests:
Get("/divide/10/5") ~> route ~> check {
  responseAs[String] shouldEqual "The result is 2"
}
Get("/divide/10/0") ~> route ~> check {
  status shouldEqual StatusCodes.BadRequest
  responseAs[String] shouldEqual "You've got your arithmetic wrong, fool!"
}
sourceimport static org.apache.pekko.http.javadsl.server.Directives.complete;
import static org.apache.pekko.http.javadsl.server.Directives.handleExceptions;
import static org.apache.pekko.http.javadsl.server.Directives.path;

final ExceptionHandler divByZeroHandler =
    ExceptionHandler.newBuilder()
        .match(
            ArithmeticException.class,
            x -> complete(StatusCodes.BAD_REQUEST, "You've got your arithmetic wrong, fool!"))
        .build();

final Route route =
    path(
        PathMatchers.segment("divide").slash(integerSegment()).slash(integerSegment()),
        (a, b) ->
            handleExceptions(divByZeroHandler, () -> complete("The result is " + (a / b))));

// tests:
testRoute(route).run(HttpRequest.GET("/divide/10/5")).assertEntity("The result is 2");
testRoute(route)
    .run(HttpRequest.GET("/divide/10/0"))
    .assertStatusCode(StatusCodes.BAD_REQUEST)
    .assertEntity("You've got your arithmetic wrong, fool!");
1.0.1