udp poc

gistfile1.txt

import dgram from 'dgram'
const procId = process.argv[2]
const myPort = process.argv[3]
const theirPort = process.argv[4]

if (!procId) {
  throw new Error("must supply a procId as the first argument")
}
if (!myPort) {
  throw new Error("must supply a port to host a udp end point as the second argument")
}
if (!theirPort) {
  throw new Error("must supply a port to another host a udp end point as the second argument")
}

const log = msg => console.log(`PROCESS ID[${procId}]: ${msg}`)

const udpsk = dgram.createSocket('udp4')

udpsk.on('error', err => {
  log(`udpsk error:\n${err.stack}`)
  udpsk.close()
})

udpsk.on('message', (msg, rinfo) => {
  log(`udpsk got: ${msg} from ${rinfo.address}:${rinfo.port}`)
})

udpsk.on('listening', () => {
  udpsk.setBroadcast(true)
  const address = udpsk.address();
  log(`udpsk listening ${address.address}:${address.port}`)
})

udpsk.bind(myPort)
console.log(`PID: ${process.pid}`)

const i = setInterval(() => {
  udpsk.send(`hello from process ${procId}`, theirPort, '255.255.255.255', err => {
    if (err) {
      console.error(err)
    }
    else {
      log('message broadcast')
    }
  })
}, 5000)

process.once('SIGINT', () => {
  clearInterval(i)
  console.log('closing udpsk...')
  udpsk.close()
  console.log('done')
  process.exit(0)
})

gistfile2.txt

{
  "name": "udp-poc",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "babel src --out-dir dist && node dist/index.js"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "babel-cli": "^6.24.1",
    "babel-preset-env": "^1.6.0"
  },
  "babel": {
    "presets": [
      [
        "env",
        {
          "targets": {
            "node": "current"
          }
        }
      ]
    ]
  }
}