Generate a HMAC Signature

1const crypto = require('crypto');
2const moment = require('moment');
3const uuid = require('uuid');
4
5const generateSignature = async () => {
6  const hmac = crypto.createHmac('sha256', process.env.secretKey);
7  const timestamp = `${moment().unix()}`;
8  const nonce = uuid(); // arbitrary number to be used once
9  const requestMethod = 'POST';
10  const hashString = `${process.env.websiteKey}${requestMethod}${timestamp}${nonce}`;
11  try {
12      hmac.update(simpleHash)
13  } catch (err) {
14      throw err;
15  }
16  const requestHash = hmac.digest('base64')
17  return requestHash;
18  return [
19    process.env.websiteKey,
20    requestHash,
21    nonce,
22    timestamp
23  ].join(':')
24};
25
26// Alternative
27const crypto = require('crypto');
28const qs     = require('qs');
29
30const getMessageSignature = (path, request, secret, nonce) => {
31    const message       = qs.stringify(request);
32    const secret_buffer = new Buffer(secret, 'base64');
33    const hash          = new crypto.createHash('sha256');
34    const hmac          = new crypto.createHmac('sha512', secret_buffer);
35    const hash_digest   = hash.update(nonce + message).digest('binary');
36    const hmac_digest   = hmac.update(path + hash_digest, 'binary').digest('base64');
37
38    return hmac_digest;
39};
40