server.js

const express = require('express');
const http = require('http');
const path = require('path');
const { Server } = require('socket.io');

const app = express();
const server = http.createServer(app);

const io = new Server(server, {
  cors: {
    origin: '*'
  },
});

// Serve static assets if in production
if (process.env.NODE_ENV === 'production') {
  // For Heroku redirection to secured layer connection in production
  app.use((req, res, next) => {
    if (req.header('x-forwarded-proto') !== 'https') {
      res.redirect(`https://${req.header('host')}${req.url}`);
    }
    else {
      next();
    }
  });

  // Set static folder
  app.use(express.static('client/build'));

  app.get('*', (req, res) => {
    res.sendFile(path.resolve(__dirname, 'client', 'build', 'index.html'));
  })
}

io.on('connection', (socket) => {
  console.log("Connected");

  let currUserId, currUserName, currRoom;

  socket.on("join-room", (roomId, id, username) => {
    console.log(roomId, id, username);
    socket.join(roomId);
    socket.to(roomId).emit("user-connected", id, username);

    currUserId = id;
    currUserName = username;
    currRoom = roomId;

    socket.on("set-info", (srcId, destId, username, streamInfo) => {
      socket.to(roomId).emit("get-info", srcId, destId, username, streamInfo);
    });

    socket.on("set-audio", (userId, isAudio) => {
      io.to(roomId).emit("get-audio", userId, isAudio);
    });

    socket.on("set-video", (userId, isVideo) => {
      io.to(roomId).emit("get-video", userId, isVideo);
    });

    socket.on("replace-stream", (userId, username) => {
      socket.to(roomId).emit("stream-replaced", userId, username);
    });

    socket.on("message-sent", (username, message) => {
      socket.to(roomId).emit("message", username, message);
    });
  });

  socket.on('disconnect', () => {
    console.log("Disonnected");
    socket.to(currRoom).emit("user-disconnected", currUserId, currUserName);
  });
});

const PORT = process.env.PORT || 5000;

server.listen(PORT, () => console.log(`Server started on port ${PORT}`));