server.js

const http = require('http');
const fs = require('fs');
const WebSocketServer = require('ws').Server;
const xss = require('xss');
// const AlchemyAPI = require('watson-developer-cloud/alchemy-language/v1');
// const key = process.env.ALCHEMY_KEY || null;
// const alchemy_client = key ? new AlchemyAPI({api_key:key}) : null;

let currentUsers = 0;
const messageHistory = [];

const port = process.env.PORT || 80;

// Basic HTTP httpServer
const httpServer = http.createServer((req, res) => {
  switch (req.url) {
    case '/':
      fs.readFile('public/index.html',
        'utf-8',
        (err, data) => res.end(data));
      break;
    case '/logo.png':
      fs.readFile('public/logo.png', (err, data) => res.end(data));
      break;
    case '/bundle.js':
      fs.readFile('public/bundle.js',
        'utf-8',
        (err, data) => res.end(data));
      break;
    default:
      res.end();
  }
});

const webSocketServer = new WebSocketServer({server: httpServer});

webSocketServer.on('connection', (ws) => {
  const payload = {
    message_type: 'initial_message_load',
    payload: messageHistory,
  };

  // Initial history
  ws.send(JSON.stringify(payload));

  ws.on('open', () => {
    console.log("Opening a connection...");
  });

  ws.on('message', (msg) => {
    const clientReply = JSON.parse(msg);

    switch (clientReply.cmd) {

    case 'connect':
      currentUsers++; break;
    case 'user_count':
      ws.send(JSON.stringify({
        users_count: `${currentUsers > 0 ? currentUsers : 0}`,
        message_type: 'user_count',
      }));
      break;
    case 'new_message':
      clientReply.payload = xss(clientReply.payload);
      messageHistory.push(clientReply.payload);
      const trimmed = clientReply.rawMessage.trim();
      const sendMeOff = JSON.stringify({
        message_type: 'new_chat_message',
        payload: clientReply.payload,
      });
      webSocketServer.clients.forEach((client) => {
	try {
	  // if (trimmed.startsWith('!hyebot.sentiment=>')) {
	  //   const analyze =
	  // 	  {text:trimmed.split('=>')[1].trim()};
	  //   if (alchemy_client) {
	  //     alchemy_client.sentiment(analyze, (e, resp) => {
	  // 	client.send(sendMeOff);
	  // 	if (e)
	  // 	  client.send(JSON.stringify({
	  // 	    message_type:'new_chat_message',
	  // 	    payload:`Watson messed up ${JSON.stringify(e)}`
	  // 	  }));
	  // 	else {
	  // 	const bot_message =
	  // 	      `{message:${trimmed}} has a score of:${resp.docSentiment.score} and its ${resp.docSentiment.type}`;
	  // 	client.send(JSON.stringify({
	  // 	  message_type:'new_chat_message',
	  // 	  payload:bot_message
	  // 	}));
	  // 	}
	  //     });
	  //   }
	  // } else {
            client.send(sendMeOff);
	  // }
	} catch (e) {
	  console.error('Tried writing to a closed socket', e);
	}
      });
      break;
    default:
      break;
    }
  });

  ws.on('close', () => {
    currentUsers--;
  });

  ws.on('error', (evt) => {
    console.log("ERR: " + evt.data);
  });
});

httpServer.listen(port, () =>
  console.log(`Server started on port:${port}, check localhost:${port}`)
);