example_order.js

const ws = require('ws')
const crypto = require('crypto')
const bfx = new ws('wss://api.bitfinex.com/ws/2')

// Replace with your own api key and secret
let api_key = ''
let api_secret = ''

// Ensure your nonce is always increasing
let nonce = Date.now()

// Payload to be sent to authenticate
let payload = {
  apiKey: api_key,
  event: 'auth',
  authPayload: 'AUTH' + nonce,
  authNonce: +nonce
}
payload.authSig = crypto.createHmac('sha384', api_secret)
  .update(payload.authPayload)
  .digest('hex')

// On open event, send authentication message
bfx.on('open', () => {
  bfx.send(JSON.stringify(payload))
})

// Here is the example order from the docs (all WS messages must be strings, hence JSON.stringify)
let order = JSON.stringify([
  0,
  'on',
  null,
  {
    gid: 1,
    cid: 12345,
    type: "LIMIT",
    symbol: "tBTCUSD",
    amount: "1.0",
    price: "500",
    hidden: 0
  }
])

// When we get the message telling us we are authenticated, send our order
bfx.on('message', (message, buffer) => {
  msg = JSON.parse(message)
  if (msg.event === 'auth' && msg.status === 'OK') {
    bfx.send(order)
  }
})