Georgiy T. Georgiy T. - 2 months ago 30
Javascript Question

How properly assign object properties is JS

I have following object:

"_id": "583c4e054c99d310f543b11e",
"cellphone": "123456",
"password": "$2a$10$d3SeD5CCzTo6wBR/4SGUu.i7vUvX98N1NlpBTwDdWCRrIYcVwWmCO",
"fullname": "some name",
"gender": "male",
"avatar": {
"_id": "583c4e054c99d310f543b11d",
"__v": 0,
"url": "",
"likesCount": 0,
"description": "Hey guys"
"__v": 0

By next code I want to create a new object without properties from mongodb (__v) and with renaming _id to id.

let plainUser = {
id: user._id,

delete plainUser._id;
delete plainUser.password;
delete plainUser.__v;
delete plainUser.avatar._id;
delete plainUser.avatar.__v;

return res.send(plainUser);

I think I can make it differently. Any suggestions how can I properly improve my code with ES6?


Better be explicit about which properties to keep instead of specifying which ones should be removed. And delete is quite inefficient. So just go for

return res.send({
    id: user._id,
    cellphone: user.cellphone,
    fullname: user.fullname,
    gender: user.gender,
    avatar: {
        url: user.avatar.url,
        likesCount: user.avatar.likesCount,
        description: user.avatar.description

For some simplification, have a look at the approach from One-liner to take some properties from object in ES 6:

const {_id: id, cellphone, fullname, gender} = user;
const avatar = (({url, likesCount, description}) => ({url, likesCount, description}))(user.avatar);
return res.send({id, cellphone, fullname, gender, avatar});