text: var crypto = require('crypto');
  
  exports.hmac = function(message, key) {
    return crypto.createHmac('sha1', key)
        .update(message)
        .digest('hex');
  };
  
  exports.atob = function(input) {
    return new Buffer(input, 'base64').toString('binary');
  };
  
  try {
    //websocket is an optional module, so it is maybe not installed
    exports.WebSocket = require('websocket').w3cwebsocket;
  } catch (e) {}
  
  
  exports.isNode = true;