A program that merges together the various archive and current feeds for In Our Time with Melvyn Bragg and delivers one feed with all the programmes ordered by broadcast date.

iotu.rb

# a program that merges together the various archive and current
# feeds for In Our Time with Melvyn Bragg and delivers one feed
# with all the programmes ordered by broadcast date.

# this was very helpful
# http://www.subelsky.com/2007/08/roll-your-own-podcast-feed-with-rails.html

require 'rss'
require 'open-uri'

# take a list of feeds
urls = {
  :iot => "http://downloads.bbc.co.uk/podcasts/radio4/iot/rss.xml",
  :iotc => "http://downloads.bbc.co.uk/podcasts/radio4/iotc/rss.xml",
  :ioth => "http://downloads.bbc.co.uk/podcasts/radio4/ioth/rss.xml",
  :iotp => "http://downloads.bbc.co.uk/podcasts/radio4/iotp/rss.xml",
  :iotr => "http://downloads.bbc.co.uk/podcasts/radio4/iotr/rss.xml",
  :iots => "http://downloads.bbc.co.uk/podcasts/radio4/iots/rss.xml",
}

# handy for local testing, downloading the feeds is laggy
# download them
# urls.each_pair do |name, value|
#   puts "#{name} => #{value}"
#   system "curl #{value} > feeds/#{name}.xml"
# end

# urls = {
#   :iot  => "feeds/iot.xml" ,
#   :iotc => "feeds/iotc.xml",
#   :ioth => "feeds/ioth.xml",
#   :iotp => "feeds/iotp.xml",
#   :iotr => "feeds/iotr.xml",
#   :iots => "feeds/iots.xml"
# }

# grab all the items
feeds = {}
items = []
urls.each_pair do |name, url|
  open(url) do |rss|
    feed = RSS::Parser.parse(rss)
    feeds[name] = feed
    items += feed.items
  end
end

feed = feeds[:iot]
  
iotu_feed = RSS::Maker.make("2.0") do |maker|
  channel = maker.channel
  channel.title = feed.channel.title
  channel.description = feed.channel.description
  channel.link = feed.channel.link
  channel.language = feed.channel.language
  channel.copyright = feed.channel.copyright
  channel.lastBuildDate = feed.channel.lastBuildDate

  image = maker.image
  image.url = feed.image.url
  image.title = feed.image.title

  channel.itunes_author = feed.channel.itunes_author
  channel.itunes_owner.itunes_name = feed.channel.itunes_owner.itunes_name
  channel.itunes_owner.itunes_email= feed.channel.itunes_owner.itunes_email

  channel.itunes_keywords = feed.channel.itunes_keywords

  channel.itunes_subtitle = feed.channel.itunes_subtitle
  channel.itunes_summary = feed.channel.itunes_summary

  # below is what iTunes uses for your "album art", different from RSS standard
  channel.itunes_image = feed.channel.itunes_image.href
  channel.itunes_explicit = "No"

  # nested data that we don't need, let's call it too hard for now
  # category = channel.itunes_categories.new_category
  # category.text = feed.channel.itunes_categories.first.text ?
  # category.new_itunes_category.text = "Literature"
    
  maker.items.do_sort = true

  items.each do |audio|
    maker.items.new_item do |item|
      item.title = audio.title
      item.link = audio.link
      item.itunes_keywords = audio.itunes_keywords
      item.guid.content = audio.link
      item.guid.isPermaLink = true
      item.pubDate = audio.pubDate
    
      item.description = audio.description
      item.itunes_summary = audio.description
      item.itunes_subtitle = audio.itunes_subtitle
      item.itunes_explicit = "No"
      item.itunes_author = audio.itunes_author
      item.itunes_duration = audio.itunes_duration.value
    
      item.enclosure.url = audio.link
      item.enclosure.length = audio.enclosure.length
      item.enclosure.type = 'audio/mpeg'
    end
  end
end
  
# publish them as an rss feed
puts iotu_feed.to_xml