GEt value of column nodejs rest and Express - node.js

Question

I am trying to obtain a column name value or multiple column name values but I am not obtaining it. I am pretty new to Nodejs but debugging it is even difficult. Here is my code:
var express = require('express');
var app = express();
var mongodb = require('mongodb');
var MongoClient = mongodb.MongoClient;
MongoClient.connect(url, function (err, db) {
if (err) {
console.log('Unable to connect', err);
} else {
console.log('Connected');
var collection = db.collection('users');
app.get('/db', function (request, response) {
collection.find({username: request.query.username, password: request.query.password}).toArray(function(err, docs) {
docs.forEach(function(doc) {
console.log(doc.toArray());
});
});
});
}
db.close();
});
I am basically authenticating if the username and password entered in db matches to my REST query and if yes then print success or redirect to a new page or something.

Answer 1

For starters, unless you are actually expecting more than one "user" to share the same "username" and "password" then you are better off using .findOne() for the singular response.
Then what is returned is just a plain JavaScript object, so just reference the properties:
collection.findOne(
{
username: request.query.username,
password: request.query.password
},
function(err,doc) {
if (err) throw err;
console.log( doc.username ); // Just the username value
}
);
If course if "nothing" is returned and there is no "error" then you didn't match anything with your criteria, so either "username" or "password" is wrong.
That's as the basic excercise, but really, authentication is a wheel that was built long ago and you would likely be better of implementing an existing module to handle it.
And get rid of db.close(). The functions here are asynchronous and this will execute before anything else completes. You basically never want to call this in real world applications.