heartbeat.js

import Device from 'zetta-device';

export default class Heartbeat extends Device {
  constructor() {
    super();
    this.pulse = null;
  }

  init(config) {
    config
      .type('heartbeat')
      .monitor('pulse')

    setInterval(() => {
      const min = 60;
      const max = 72;

      this.pulse = Math.round(Math.random() * (max - min) + min, 2);
    }, 1000);
  }
}

led.js

import Device from 'zetta-device'

export default class LED extends Device {
  init(config) {
    config
      .type('led')
      .state('off')
      .when('off', { allow: ['turn-on'] })
      .when('on', { allow: ['turn-off'] })
      .map('turn-on', this.turnOn)
      .map('turn-off', this.turnOff);
  }

  turnOn(cb) {
    this.state = 'on';
    cb();
  }

  turnOff(cb) {
    this.state = 'off';
    cb();
  }
}

package.json

{
  "name": "asfasdfsfasd",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "dependencies": {
    "babel-runtime": "5.6.12",
    "zetta": "^0.30.0",
    "zetta-device": "^0.11.0"
  },
  "devDependencies": {
    "babel": "5.6.12"
  },
  "scripts": {
    "build": "rm -rf lib/* && babel src --ignore __tests__ --optional runtime --optional es7.classProperties --out-dir lib",
    "server": "npm run build && node lib/server.js"
  },
  "author": "",
  "license": "ISC"
}

server.js

import zetta from 'zetta';
import LED from './led';
import Heartbeat from './heartbeat';

zetta()
  .use(LED)
  .use(Heartbeat)
  .listen(process.env.PORT || 1337);