code: function createShardIterator(streamName, shardId, seq) {
    var encryptStr = [
        (new Array(14).join('0') + Date.now()).slice(-14),
        streamName,
        shardId,
        seq,
        new Array(37).join('0'), // Not entirely sure what would be making up all this data in production
      ].join('/'),
      cipher = crypto.createCipher('aes-256-cbc', exports.ITERATOR_PWD),
      buffer = Buffer.concat([
        new Buffer([0, 0, 0, 0, 0, 0, 0, 1]),
        cipher.update(encryptStr, 'utf8'),
        cipher.final(),
      ])
    return buffer.toString('base64')
  }
docs: Length depends on name length, given below calculation: 152 + (Math.floor((data.StreamName.length + 2) / 16) * 16)