if (params['_source'] != null 
    && params['_source'].containsKey("message") 
    && params['_source']["message"] != null) {
  String msg = params['_source']["message"];
  int pos = msg.indexOf("created");
  if (pos >= 0) {
    // Get everything after the word "created" and trim any extra whitespace
    String output = msg.substring(pos + "created".length()).trim();
    emit(output);
  } else {
    emit(null);
  }
} else {
  emit(null);
}