Function interledger_service::incoming_service_fn

pub fn incoming_service_fn<A, B, F>(handler: F) -> ServiceFn<F, A> where
    A: Account,
    B: IntoFuture<Item = Fulfill, Error = Reject>,
    F: FnMut(IncomingRequest<A>) -> B, 

Create an IncomingService that calls the given handler for each request.