RSS Feeds Using logstash

I am fetching RSS Feeds using logstash-input-rss plugin. I am mainly facing three problems as below. It will be great if someone can give me insgihts.

  1. How to avoid repetition of items?
    i.e. same item is indexed after the time interval, but I want to index only if a new data is added to the feed URL independent of the time interval.
  2. There are various feeds which are not compatible, how to fix them and parse them too?
  3. I'm trying to search using "GET index_name/_search?q=title:*"
    Its working fine, I just want to output few fields from the searched query, is it possible?