javascript - new - La promesa de NodeJS Bluebird creada en un controlador pero no fue devuelta

node js

Question

Tengo el siguiente código de nodojs como una función de middleware express

Middleware.is_authenticated = function(req, res, next)
{
    if(req.system_session == undefined || req.system_session.login_status == false) return res.status(401).send({errors: true, error: ''invalid_session'', session: req.system_session}).end();

    Session.validate_session(req.system_session, req.ip, req.headers[''user-agent''])

    .then(function(session)
    {
        return next();
    })

    .catch(function(err)
    {
        req.system_session.destroy();
        return res.status(401).send({errors: true, error: err.message, session: req.system_session}).end();
    });
};

Mi Session.validate_session code:

Session.validate_session = function(user, user_ip, user_agent)
{
    return new Promise(function(resolve, reject)
    {
        if(user.user_id == null || user.user_name == null || user.user_rank == null || user.user_session == null || user_ip == null || user_agent == null) return reject(new Error(''invalid_session''));

        new api_session({user_session: user.user_session}).fetch({columns: [''user_id'', ''user_name'', ''user_rank'', ''user_session'', ''user_ip'', ''user_agent'']})

        .then(function(result)
        {
            if(result == null) return reject(new Error(''invalid_session''));

            return result.toJSON();
        })

        .then(function(session)
        {
            if(session == null || session.user_id != user.user_id || session.user_name != user.user_name || session.user_rank != user.user_rank || session.user_ip != user_ip || session.user_agent != user_agent) return reject(new Error(''invalid_session''));

            return resolve(session);
        })

        .catch(function(err)
        {
            return reject(err);
        });
    });
};

Todo está funcionando exactamente como debería, todo se ejecuta sin problemas con la base de datos, así como resolver la ''siguiente'' ruta e incluso mostrar la respuesta. Pero no importa lo que intento, sigo obteniendo ''una promesa creada en un controlador pero no fue devuelta''

Warning: a promise was created in a handler at middleware.js:12:11 but was not returned from it

at new Promise (/Users/Bill/Documents/app/node_modules/bluebird/js/release/promise.js:77:14)
at Object.Permission.permission_list (/Users/Bill/Documents/app/app/security/permission.js:8:10)
at PermissionService.permission_list (/Users/Bill/Documents/app/app/http/services/permission_service.js:6:14)
at Layer.handle [as handle_request] (/Users/Bill/Documents/app/node_modules/express/lib/router/layer.js:95:5)
at next (/Users/Bill/Documents/app/node_modules/express/lib/router/route.js:131:13)
at /Users/Bill/Documents/app/app/http/middleware.js:12:11
at processImmediate [as _immediateCallback] (timers.js:383:17)

From previous event:
at Middleware.is_authenticated (/Users/Bill/Documents/app/app/http/middleware.js:10:4)
at Layer.handle [as handle_request] (/Users/Bill/Documents/app/node_modules/express/lib/router/layer.js:95:5)
at next (/Users/Bill/Documents/app/node_modules/express/lib/router/route.js:131:13)
at Route.dispatch (/Users/Bill/Documents/app/node_modules/express/lib/router/route.js:112:3)
at Layer.handle [as handle_request] (/Users/Bill/Documents/app/node_modules/express/lib/router/layer.js:95:5)
at /Users/Bill/Documents/app/node_modules/express/lib/router/index.js:277:22
at Function.process_params (/Users/Bill/Documents/app/node_modules/express/lib/router/index.js:330:12)
at next (/Users/Bill/Documents/app/node_modules/express/lib/router/index.js:271:10)
at clientSession (/Users/Bill/Documents/app/node_modules/client-sessions/lib/client-sessions.js:630:5)
at Layer.handle [as handle_request] (/Users/Bill/Documents/app/node_modules/express/lib/router/layer.js:95:5)
at trim_prefix (/Users/Bill/Documents/app/node_modules/express/lib/router/index.js:312:13)
at /Users/Bill/Documents/app/node_modules/express/lib/router/index.js:280:7
at Function.process_params (/Users/Bill/Documents/app/node_modules/express/lib/router/index.js:330:12)
at next (/Users/Bill/Documents/app/node_modules/express/lib/router/index.js:271:10)
at SendStream.error (/Users/Bill/Documents/app/node_modules/express/node_modules/serve-static/index.js:121:7)
at emitOne (events.js:77:13)
at SendStream.emit (events.js:169:7)
at SendStream.error (/Users/Bill/Documents/app/node_modules/express/node_modules/send/index.js:275:17)
at SendStream.onStatError (/Users/Bill/Documents/app/node_modules/express/node_modules/send/index.js:392:12)

Si alguien tiene alguna solución, sería genial. Tengo muchas promesas en mi proyecto que son extremadamente similares y todas funcionan estupendamente, pero no puedo entender esto.

Answer 1

Esto proviene de la combinación de código basado en promesas ( Session.validate_session ) con código basado en devolución de llamada ( next ). Sería de esperar que la next() llamada no sea asincrónica (no cree ninguna promesa) o devuelva esa promesa, que no (culpa de expresar).

Hay dos formas de evitar la advertencia:

• Deje que express haga el manejo de errores, y llame a next con un error si ocurre. En este caso, puede usar el método .asCallback :

  Middleware.is_authenticated = function(req, res, next) {
      if (req.system_session == undefined || req.system_session.login_status == false)
          var promise = Promise.reject(new Error(''invalid_session''));
      else
          var promise = Session.validate_session(req.system_session, req.ip, req.headers[''user-agent'']);
  
      promise.asCallback(next);
  };

• Como dice la explicación de advertencia , puede return null explícitamente en lugar de devolver el valor undefined que arroja next() :

  Middleware.is_authenticated = function(req, res, next) {
      if (req.system_session == undefined || req.system_session.login_status == false)
          var promise = Promise.reject(new Error(''invalid_session''));
      else
          var promise = Session.validate_session(req.system_session, req.ip, req.headers[''user-agent''])
          .catch(function(err) {
              req.system_session.destroy();
              throw err;
          });
  
      promise.then(function(session) {
          next();
          return null;
      }, function(err) {
          res.status(401).send({errors: true, error: err.message, session: req.system_session}).end();
      });
  };