Dev Diary #3 - Require Auth Data with Middleware

requireAuthData.tsx

import User from "@eximchain/dappbot-types/spec/user";

export const requireAuthData:MiddlewareFunction<UniversalArgs> = (args) => {

  // This function will show the user an error and then
  // exit the process, preventing the command handler
  // from ever actually being called.
  function authErr() {
    render(
      <ErrorBox errMsg={"This command requires you to log in; please call 'dappbot signup' or 'dappbot login'."} />
    )
    process.exit(1);
  }
  
  // Make sure there is an auth file
  if (!args.authFile) {
    authErr();
    return;
  }
  const authData = JSON.parse(args.authFile);
  
  // Make sure it has the appropriate shape
  if (!User.isAuthData(authData)) {
    authErr(); 
    return;
  }
  
  // Our authStatus helper function tells us
  // whether a valid AuthData object is active,
  // stale, or empty.  We can refresh if stale,
  // but if it's empty bail out.
  if (User.authStatus(authData).isEmpty) {
    authErr()
    return;
  }
  
  // If all these checks pass successfully,
  // we either have an active login or we
  // have a stale one which will be
  // refreshed upon <App> mount.
  // Good to go!
  return args;
}