Akka authenticateOAuth2Async: credentials missing - authentication

Question

I have the following:
def myUserPassAuthenticator(credentials: Credentials): Future[Option[String]] = {
log.info(credentials.toString)
credentials match {
case p#Credentials.Provided(id) if p.verify("a") =>
log.info("Login success!")
Future.successful(Some(id))
case _ =>
log.info("Login failure!")
Future.successful(None)
}
}
val authRoute = path("login") {
authenticateOAuth2Async(realm = "secure site", myUserPassAuthenticator) { userName =>
complete(s"The user is '$userName'")
}
}
when navigating to that endpoint and entering credentials, the log line
log.info(credentials.toString)
just becomes Missing. What is wrong here?
The content-type of the request is "application/x-www-form-urlencoded"
and the data is "grant_type=password&username=INSERT_USERNAME_HERE&password=INSERT_PWD_HERE"

Answer 1

You should wrap your route in Route.seal directive:
val authRoute =
Route.seal {
path("login") {
authenticateOAuth2Async(realm = "secure site", myUserPassAuthenticator) { userName =>
complete(s"The user is '$userName'")
}
}
}
from documentation it seems to rely on default rejection 401 if authentication fails
Given a function returning Some[T] upon successful authentication and
None otherwise, respectively applies the inner route or rejects the
request with a AuthenticationFailedRejection rejection, which by
default is mapped to an 401 Unauthorized response.
and the Route.seal provides exactly that:
A Route can be "sealed" using Route.seal, which relies on the in-scope
RejectionHandler and ExceptionHandler instances to convert rejections
and exceptions into appropriate HTTP responses for the client.