gistfile1.txt

var Bitstamp = function(){
  
  this.host = "https://www.bitstamp.net";
  this.path = "/api/";
  
  this.balances = {};
  
  this.initialize = function() {
    var pp      = PropertiesService.getScriptProperties();
    this.key    = pp.getProperties()['bitstamp_key'];
    this.secret = pp.getProperties()['bitstamp_secret'];
    this.customer_id = pp.getProperties()['bitstamp_id'];
  };
  
  this.createSignature = function(nonce) {
    var message = nonce + this.customer_id + this.key;
    
    var res = Utilities.computeHmacSha256Signature(message, this.secret).map(function(e) {return ("0" + (e < 0 ? e + 256 : e).toString(16)).slice(-2)}).join("");
    
    return res.toUpperCase();
  };
  
  
  
  this.getBalancesV2 = function() {
    
    var url = this.host + this.path;
    var sub_path = "v2/balance/";
    url += sub_path;
    
    var nonce = this.generateUUID();
    var timestamp = ""+new Date().getTime();
    var signature = this.createSignatureV2("post", sub_path, "", nonce, timestamp, "");
    
    var headers = {
      'X-Auth'           : "BITSTAMP " + this.key,
      'X-Auth-Signature' : signature,
      'X-Auth-Nonce'     : nonce,
      'X-Auth-Timestamp' : timestamp,
      'X-Auth-Version'   : 'v2',
      'contentType'      : "application/x-www-form-urlencoded"
    };
    
    var options = {
        "method"             : "post",
        "muteHttpExceptions" : true,
        "headers"            : headers,
        "payload"            : {}
    };
    
    var response = UrlFetchApp.fetch(url, options);
    var balances = JSON.parse(response.getContentText());
    
    Logger.log(response);
    
    this.balances = {
      'usd' : balances['usd_balance'],
      'btc' : balances['btc_balance'],
      'eth' : balances['eth_balance'],
      'ltc' : balances['ltc_balance'],
      'bch' : balances['bch_balance'],
      'eur' : balances['eur_balance']
    }
    
    return balances; 
  };

  
  this.generateUUID = function() {
    return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
      var r = Math.random() * 16 | 0, v = c == 'x' ? r : (r & 0x3 | 0x8);
      return v.toString(16);
    });
  };
    
  this.createSignatureV2 = function(verb, sub_path, query, nonce, timestamp, request_body) {
     
    var message = "BITSTAMP " + this.key + verb + this.host + this.path + sub_path + query + "application/x-www-form-urlencoded" + nonce + timestamp + 'v2' + request_body;

    var res = Utilities.computeHmacSha256Signature(message, this.secret).map(function(e) {return ("0" + (e < 0 ? e + 256 : e).toString(16)).slice(-2)}).join("");
    
    return res.toUpperCase();
    
  };
  
  // run this every time the object is created
  this.initialize();
};