Socket.io multiplayer basis

socket.io_client.js

const Client = {
            socket: io(),
            zombieManager: false,
            newPlayer: function(){
                this.socket.emit('newplayer');
            },
            playerMove: function(x, y){
                this.socket.emit('move', {x, y});
            },
            shootBeam: function(x, y, angle, velocity){
                this.socket.emit('shot', {x, y, angle, velocity});
            },
            hitBeam: function(bulletID){
                this.socket.emit('hitshot', bulletID);
            },
            moveZombie: function(id, x, y){
                if(this.zombieManager){
                    this.socket.emit('moveZombie', {id, x, y});
                }
            },
            initListeners: function(){
                this.socket.on('newplayer', function(player){
                    console.log('add', player);
                });
                this.socket.on('allplayers', function(players){
                    console.log('create game players with', players);
                });
                this.socket.on('allbullets', function(bullets){
                    console.log('create game bullets with', bullets);
                });
                this.socket.on('allzombies', function(zombies){
                    console.log('create game zombies with', zombies);
                });
                this.socket.on('zombiemanager', () => {
                    this.zombieManager = true;
                    console.log('This socket will be the zombie manager');
                })
                this.socket.on('move', function(coords){
                    console.log('tween to', coords);
                });
                this.socket.on('zombiesUpdate', function(zombies){
                    console.log('zombies update positions', zombies);
                });
                this.socket.on('newbullet', function(bullet){
                    console.log('create new bullet', bullet)
                });
                this.socket.on('destroybullet', function(bulletID){
                    console.log('destroy bullet', bulletID);
                })
                this.socket.on('remove', function(id){
                    console.log('remove', id);
                });
            }
        };
        Client.initListeners();
        Client.newPlayer();
        //Client.playerMove(100, 200);
        //Client.shootBeam(100, 200, 90, {x: 10, y: 10});

socket.io_server.js

const express = require('express'); // Express contains some boilerplate to for routing and such
const app = express();
const http = require('http').Server(app);
const io = require('socket.io')(http); // Here's where we include socket.io as a node module

// Serve the index page
// app.get("/", function (request, response) {
//   response.sendFile(__dirname + '/index.html');
// });

// Serve the assets directory
app.use(express.static(__dirname + '/public'));
app.use('/assets', express.static('assets'));

// Listen on port 5000
const port = process.env.PORT || 5000;
http.listen(port, function() {
    console.log('listening on port', port);
});

let nextPlayerID = 0;
let gameBullets = [];
let gameZombies;

function getAllPlayers(){
    return Object.keys(io.sockets.connected).map(socketID => io.sockets.connected[socketID].player);
}

// Tell Socket.io to start accepting connections
io.on('connection', function(socket) {
    if(Object.keys(io.sockets.connected).length <= 1){
        gameZombies = [];
        gameZombies.push({x: 10, y: 0, velocity: {x: 5, y: 0}});
        gameZombies.push({x: 20, y: 50, velocity: {x: 0, y: 5}});
        gameZombies.push({x: 30, y: 100, velocity: {x: 5, y: 0}});
        socket.emit('zombiemanager');
    }
    socket.on('newplayer', function(){
        socket.player = {
            id: nextPlayerID++,
            x: 0,
            y: 0
        }
        console.log(socket.player);
        socket.emit('allplayers', getAllPlayers());
        socket.emit('allbullets', gameBullets);
        socket.emit('allzombies', gameZombies);
        socket.broadcast.emit('newplayer', socket.player);

        socket.on('moveZombie', function(zombie){
            gameZombies[zombie.id].velocity.x = zombie.x;
            gameZombies[zombie.id].velocity.y = zombie.y;
            socket.broadcast.emit('zombiesUpdate', gameZombies);
        })

        socket.on('move', function(coords){
            console.log(coords);
            socket.player.x = coords.x;
            socket.player.y = coords.y;
            io.emit('move', socket.player);
        });

        socket.on('shot', function(coords){
            var bullet = Object.assign(coords, {
                id: new Date().getTime()
            });
            gameBullets.push(bullet);
            io.emit('newbullet', bullet);
        });

        socket.on('hitshot', function(id){
            gameBullets = gameBullets.filter(bullet => bullet.id != id);
            io.emit('destroybullet', id);
        });

        socket.on('disconnect', function(){
            io.emit('remove', socket.player.id);
        });
    })
})