Populating and selecting multiple sub-documents mongoose - mongodb

Question

I have a User Model
const UserSchema = new mongoose.Schema({
name: {
type: String,
required: true
}
email: {
type: String,
required: true,
maxlength: 128,
minlength: 5
},
hashedPassword: {
type: String,
required: false
}
});
module.exports = mongoose.model('users', UserSchema);
And a Post Model
const mongoose = require('mongoose');
const PostSchema = new mongoose.Schema({
description: {
type: String,
required: true
},
comments: [{
comment: {
type: String,
required: true
},
postedBy: {
type: mongoose.Schema.Types.ObjectId,
required: true,
ref: 'users'
},
postedOn: {
type: Date,
required: true,
default: Date.now
}
}],
postedBy: {
type: mongoose.Types.ObjectId,
required: true,
ref: 'users'
}
});
module.exports = mongoose.model('answers', AnswerSchema);
I want to fetch post with populated "postedBy"(of POST) also select fields of "name and email" from "postedBy"(of POST). Also, I want to populate "postedBy"(inside comments) and select the same field of "name and email" from "postedBy"(inside comments).
Expecting to see a result like
{
"post": [
{
"_id": "*some mongo id*",
"description": "This is a sample Post for testing",
"postedBy": {
"_id": "5e9285669bdcb146c411cef2",
"name": "Rohit Sharma",
"email": "rohit#gmail.com"
},
"comments": [{
"comment": "Test One Comment",
"postedBy": {
"_id": "5e9285669bdcb146c411cef2",
"name": "Rohit Sharma",
"email": "rohit#gmail.com"
},
}],
"postedOn": "2020-04-19T12:28:31.162Z"
}
]
}