Question

我正在尝试在登录过程中获取用户数据。数据存储在rethinkDb中。流程是：

•请求被路由到控制器（通过快递）

•控制器选择正确的处理程序

•处理程序调用dao.get（）：

  login: function (email, password, res) {
        var feedback = daouser.get(email);
        if (feedback.success) {
            var user = feedback.data;
            //Do some validatios...
        }       
        res.status = 200;
        res.send(feedback);
    },

•dao.get（）代码是：

get: function (email) {        
    var feedback = new Feedback();
    self.app.dbUsers.filter({email: email}).run().then(function (result) {
        var user = result[0];
        feedback.success = true;
        feedback.data = user;
        return feedback;
    });
}

但由于调用是通过promise，dao.get在实际的“Then”函数返回之前返回，控制器获得 undefined 反馈...

我的设计有问题......

Answer 1

var feedback = daouser.get(email);

你不能在这里进行同步分配，因为.get是异步的。此外，请注意您没有从.get返回任何内容，这就是为什么它未定义。我将所有这些都作为承诺链。

get: function (email) {        
var feedback = new Feedback();

// RETURN is important here, this way .get() return a promise instead of undefined
return self.app.dbUsers.filter({email: email}).run().then(function (result) {
    var user = result[0];
    feedback.success = true;
    feedback.data = user;
    return feedback;
});

}

login: function (email, password, res) {
    //return the promise again, so login will be chainable too
    return daouser.get(email)
    // You can chain another then here, because you returned a promise from .get above
    // Your then function will be called with the return from the previous then, which is 'feedback'
    .then(function(feedback) {
      if (feedback.success) {
        var user = feedback.data;
        //Do some validatios...
      }       
      res.status = 200;
      res.send(feedback);
  }
},

如何控制以异步操作为目标的http请求

1 个答案: