Reactive Programming With MEAN stack

Question

I’m thinking about starting to develop a social network similar to Instagram, for learning purposes, using MEAN stack. I thought of my models :

User’s:

var mongoose = require('mongoose');

module.exports = mongoose.model('User', {
    email: String,
    username: String,
    password: String,
    image: String,
    bio: String,
	following: [{userId: String}],
	followers: [{userId: String}]
});

var mongoose = require('mongoose');

module.exports = mongoose.model('Post', {
user: String,
userId: String,
userImage: String,
content: String,
date: {type: Date, default: Date.now}
})

wanted to do something to work in more real time, so that when a user makes a post, who is following him and is logged in to receive this post in his $Scope, I don’t know if I can do something like this with the socket.io, or put a setInterval() to keep checking every 1 minute, I’m thinking about architecture still, I’m very beginner still in this world of MEAN. I accept every idea, every secret.