Node.js: view data in controller called from model

Question

I want to assign data return from the model, then on console.log i only see undefined

My code is:

var dmodel  = require('../models/database');
dmodel.myfunction(request,response, function (err, user) {
         console.log(user); // see data
});

Then I repair code:

var dmodel  = require('../models/database');
var userinfo;
dmodel.myfunction(request,response, function (err, user) {
            userinfo = user;
});
console.log(userinfo); // undefined, not see data

How do it ? Thanks all

This is my function:

module.exports = {
    myfunction: function (request,response, callback) {
        var query = "select * from mytable";
        //call functionexcecute query
        executeQuery(query, function (err, rows) {
            if (!err) {           
                var user = rows;            
                callback(null, user);
            } else {
                console.log(err);
            }
        });
    }
};

You will only get user info in the callback only. This is async nature — Gaurav joshi, Jan 06 '17 at 07:01

user · Accepted Answer · 2017-01-06T07:17:03.467

0

Due to asynchronous nature of javascript, code console.log(userinfo) is getting executed before the callback function is called.
Modified code:

var dmodel  = require('../models/database');
var userinfo;
dmodel.myfunction(request,response, function (err, user) {
        userinfo = user;
        console.log(userinfo);
});

That is, your earlier code was correct. If the value printed is still undefined, that means there is some issue with the definition of function executeQuery.

edited Jan 06 '17 at 07:17

answered Jan 06 '17 at 07:10

user

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Thank you, but i want to view data console.log(userinfo) outsite myfunction beacuse I want to call another funtion then i do two array data. – tutran Jan 06 '17 at 07:19
You have to write code is such a way that _console.log(userinfo)_ gets executed after callback function is executed. One way is to write the logic that is written after the function _dmodel.myfunction_ in another function and call that function inside the callback, once the value is assigned to _userinfo_. – user Jan 06 '17 at 07:24
I will try, thank you – tutran Jan 06 '17 at 08:15

score 0 · Answer 2 · answered Jan 06 '17 at 07:22

you can use a .then promise which will wait for the first function to complete its execution

 var dmodel  = require('../models/database');
    var userinfo= {};
    dmodel.myfunction(request,response, function (err, user) {
                userinfo = user;
                return userinfo;
    }).then(function(data){
    console.log(userinfo);
    })

Node.js: view data in controller called from model

2 Answers2