compare 2 rss feeds and create nginx redirects

rss_redirector.rb

#!/usr/bin/env ruby

require 'httparty'
require 'feedjira'

def get_feed(source)
  if source.start_with?("http")
    xml = feed_from_url(source)
  else
    xml = feed_from_file(source)
  end
  Feedjira.parse(xml)
end

def feed_from_url(url)
  HTTParty.get(url).body
end

def feed_from_file(path)
  File.open(path, 'r').read
end

def feed_to_hash(feed)
  feed.entries.inject(Hash.new) do |memo, entry|
    memo[entry.id] = entry.url.sub(/https?\:\/\/devchat\.tv/, '') if entry.url && !entry.url.include?("/bonus/")
    memo
  end
end

original = feed_to_hash(get_feed(ARGV[0]))
new_feed = feed_to_hash(get_feed(ARGV[1]))

redirects = original.inject("") do |memo, (guid, orig_url)|
  new_url = new_feed[guid]
  memo << "location = #{orig_url} {\n  return 301 #{new_url};\n}\n\n"
  memo
end

File.open("./redirects", "wb") do |file|
  file.puts redirects
end