Postman pre-request script for wsc hmac auth

wsc-hmac-auth.js

pm.variables.set("wsc-api-key", "XXXXXXXXX");

// get and set a timestamp in seconds (Unix epoch)
var timestamp = Math.floor(Date.now() / 1000);
pm.variables.set("wsc-timestamp", timestamp);
console.log("timestamp=" + timestamp);

//normalize Postman path object
console.log("pm.request.url.path=" + pm.request.url.path)
var path = "/";  // force leading slash
// add path, converting commas to slashes
path = path.concat(pm.request.url.path.toString().replace(/,/g, "/"));
// defensive code to make sure last char is NOT a slash
if (path.charAt(path.length - 1) == "/") {
    path = path.slice(0,path.length - 1);
}
console.log("normalized path=" + path);

// get secret API key from environment
var apikey = pm.variables.get("wsc-api-key");

//construct data string with required components
var data = timestamp + ":" +  path + ":" + apikey;
console.log("data=" + data);

// compute signature
var signature = CryptoJS.HmacSHA256(data, apikey).toString();
console.log("signature=" + signature);

// set Postman variable for signature
pm.variables.set("wsc-signature", signature);