Grant Signature PubNub Access Manager (PAM) HMAC SHA-256 - JavaScript

sign-grant.html

Open Dev Console

<script>(async ()=>{
'use strict';

let secret = "sec-demo";
let enc = new TextEncoder("utf-8");
let body = "GET\npub-demo\n/v2/auth/grant/sub-key/sub-demo\nauth=myAuthKey&g=1&target-uuid=user-1&timestamp=1595619509&ttl=300";
let algorithm = { name: "HMAC", hash: "SHA-256" };

let key = await crypto.subtle.importKey("raw", enc.encode(secret), algorithm, false, ["sign", "verify"]);
let signature = await crypto.subtle.sign(algorithm.name, key, enc.encode(body));
let digest = btoa(String.fromCharCode(...new Uint8Array(signature)));

console.log(digest);

})();</script>

Async/Await Crypto Subtle HMAC SHA-256 with Base64 Digest

The following is a copy of the ✅ StackOverflow Crypto Subtle answer. This time we are using async/await for clean syntax. This approach also offers a base64 encoding digest.

• body is the string-to-sign.
• enc is a text encoder that converts the UTF-8 to JavaScript byte arrays.
• algorithm is a JS object which is used to identify the signature methods.
• key is a CryptoKey.
• signature is the byte array hash.
• digest is the base64 encoded signature.