ico-bench.js

const request = require('request')
const hmacSha384 = require('crypto-js/hmac-sha384')
const btoa = require('btoa')

const pubKey = 'my-pub-key'
const priKey = 'my-pri-key'

const data = JSON.stringify({'hello': 'world'})

// Hash the data with the private key then Base64 encode
const priKeyHash = hmacSha384(data, priKey)
const priKeyBase64 = btoa(priKeyHash)

// also tried this:
// const priKeyBase64 = Buffer.from(JSON.stringify(priKeyHash)).toString('base64')

const options = {
  url: 'https://icobench.com/api/v1/other/stats',
  headers: {
    'Content-Type': 'application/json',
    'X-ICObench-Key': pubKey,
    'X-ICObench-Sig': priKeyBase64
  }
};  

request.post(options, (error, response, body) => {
  if (!error && response.statusCode == 200) {
    const info = JSON.parse(body);
    console.log(info)
  }
})