login-desugar.scala

def login(dbConn: DbConnection, req: Request): Try[Response] =
  req.body.flatMap { reqJsonStr =>
    json.parse(reqJsonStr).flatMap { reqJson =>
      validateAndDecode[LoginRequest](reqJson).flatMap { loginReq =>
        dbConn.findUser[UserDetails](dbConn, loginReq.username).flatMap { userDetails =>
          doesPasswordMatch(userDetails.hashedPassword, loginReq.password).flatMap { _ =>
            jwt.generateToken(loginReq.username).map { jwtToken =>
              Response(200, json.encode(Map("token" -> jwtToken)))
            }
          }
        }
      }
    }
  }