indicare.rb

require 'net/http'
module Indicare
  class NewsFeedItemProcessor < Larva::Processor
    def news_feed_item_created
      publish_to_flumen
    end

    private
    def publish_to_flumen
      nfi = MeducationSDK::NewsFeedItem.find(id)
      message = {
        type: :news_feed_item,
        payload: NewsFeedItemSerializer.serialize(nfi).to_json
      }

      Indicare.config.logger.info "Posting message to flumen"
      uri = URI('http://flow.meducation.net:3004')
      unless retry_post(uri, message)
        Indicare.config.logger.error "Message POST failed: #{res.code}: #{res.message}"
        raise IndicareError.new("Message failed to post to flumen")
      end
    end

    def retry_post(uri, message)
      max_posts = Indicare.config.max_post_retries
      delay = Indicare.config.initial_post_retry_delay

      max_posts.times do |post_count|
        begin
          Indicare.config.logger.info "Attempting POST #{post_count}"
          res = Net::HTTP.post_form(uri, message)
          if res.code == '200'
            Indicare.config.logger.info "POST #{post_count} successful"
            return true
          else
            Indicare.config.logger.error "POST #{post_count} failed with response: #{res.code} - sleeping for #{delay} seconds"
          end
        rescue => e
          Indicare.config.logger.error "POST #{post_count} failed with exception: #{e.message} - sleeping for #{delay} seconds"
          raise if (post_count - 1) == max_posts
        end
        sleep delay
        delay = delay * 2
      end
      false
    end
  end
end