Can't access fields of MongoDB document in Node.Js - node.js

Question

I'm using mongoose and express on my nodejs project.
Trying to get the data from here
app.get('/offers/:id', (req, res) =>{
//store the id from the url
var id = req.params.id;
//just a placeholder
var data = {title: "title", description:"description"};
//store the returned object in a variable
var oop = offers.findById(id, function (err, user) {
if(err){
return err;
}else{
title = user.title;
description = user.description;
this.obj = {
title:title,
description:description
}
console.log(obj)
return obj;
}
} );
console.log(oop)
res.render('single', {data:data});
});
so my idea is to grab the post id from the url, find it in the database, then display the title and description in the corresponding place on the ejs template, but for some reason I can't access the returned data, and what I get is a long list of objects that belongs to mongodb, without the presence of "title" or "description"

Answer 1

Try this, your code has couple of issues & also you need use .lean() to get raw Js objects rather than mongoDB documents :
app.get('/offers/:id', (req, res) => {
//store the id from the url
var id = req.params.id;
//just a placeholder
var data = { title: "title", description: "description" };
//store the returned object in a variable
offers.findById(id).lean().exec((err, user) => {
if (err) {
console.log(err);
res.send(err)
} else {
data.title = user.title;
data.description = user.description;
this.obj = {
title: title,
description: description
}
console.log(obj);
res.render('single', { data: data });
// (Or) res.render('single', { data: obj });
}
});
});

Answer 2

I just modified your code and added comments (all starting with "***").
app.get('/offers/:id', (req, res) =>{
//store the id from the url
var id = req.params.id;
//just a placeholder
var data = {title: "title", description:"description"};
//store the returned object in a variables
// var oop = ***no need for this, the data you want will be in the user variable.
offers.findById(id, function (err, user) {
if(err){
return err;
}else{
// ***this needs to be changed to...
// title = user.title;
// description = user.description;
// ***that...
data.title = user.title;
data.description = user.description;
// ***what's that for??
// this.obj = {
// title:title,
// description:description
// }
// ***this needs to be inside mongoose's callback
res.render('single', {data:data});
}
});
});