1  var ms = require('ms');
 2  
 3  module.exports = function (time, iat) {
 4    var timestamp = iat || Math.floor(Date.now() / 1000);
 5  
 6    if (typeof time === 'string') {
 7      var milliseconds = ms(time);
 8      if (typeof milliseconds === 'undefined') {
 9        return;
10      }
11      return Math.floor(timestamp + milliseconds / 1000);
12    } else if (typeof time === 'number') {
13      return timestamp + time;
14    } else {
15      return;
16    }
17  
18  };