optionalHeaderValuePF
Calls the specified partial function with the first request header the function is isDefinedAt
and extracts the
result of calling the function.
Signature
def optionalHeaderValuePF[T](pf: PartialFunction[HttpHeader, T]): Directive1[Option[T]]
Description
The optionalHeaderValuePF
directive is similar to the headerValuePF
directive but always extracts an Option
value instead of rejecting the request if no matching header could be found.