Postman Pre-request script to add signatures to work with django-rest-framework-httpsignature

gistfile1.txt

/**
 *     How to use
 *
 *  1. Place below script in "Pre-request Script" tab in Postman, change "apiKey" and "apiSecret" variable.
 *  2. In the "Headers" tab, reference the value as "{{authorisation}}" as per your predefined header name, 
 *     typically "authorization"      
 *  3. Depending on your server side setup, add header "x-api-key" to your KEY.
 *
 *   Tested with Postman Version 6.0.9
 *
 */ 
 

var apiKey = 'WFTJJLB344ZJGTG2G83B';
var apiSecret = 'iiHNoVhT9r47r93msq5SDgmd0ICIH9mLD4CnfmBM';


var method = request.method;

var hostMatch = /\/\/(\w+:\d{3,4})/.exec(request.url);
var host = hostMatch[1];

var pathMatch = /:\d{3,4}(.+)/.exec(request.url);
var path = pathMatch[1];

var signatureContentString = [
    '(request-target): ' + method.toLowerCase() + ' ' + path,
    'host: ' + host.toLowerCase(),
    'x-api-key: ' + apiKey
].join('\n');

var signatureString = CryptoJS.HmacSHA256(signatureContentString, apiSecret).toString(CryptoJS.enc.Base64);

var authHeader = 'Signature algorithm="hmac-sha256",headers="(request-target) host x-api-key", signature="' 
    +  signatureString + '"';

pm.globals.set("authorisation", authHeader);