about.md

serial: https://hackernoon.com/arduino-serial-data-796c4f7d27ce

ws server: https://www.npmjs.com/package/ws#simple-server

client code for sketch.js: https://github.com/mattdesl/bartlett-dfpi-rpi/blob/87fef204bfd42d1c994e9062f41505bc03f3a0b3/demos/accelerometer/sketch.js#L13-L26

--

install error: https://github.com/nodejs/node-gyp#option-1

server.js

const WebSocket = require("ws");
const wss = new WebSocket.Server({ port: 8080 });

let newData;

// ---
// somehow get newData from serialport
// ---

...

// ---
// send to websocket clients
// ---

setInterval(update, 1000 / 30);

function update() {
  const obj = {
    data: newData
  };
  const str = JSON.stringify(obj);
  const clients = Array.from(wss.clients);
  for (let i = 0; i < clients.length; i++) {
    const client = clients[i];
    client.send(str);
  }
}