Generates RSS file from the files in a folder with subfolders

podcast_generator.rb

#!/usr/bin/env ruby -wKU
#
# based on a script
# by Kelan Champagne
# http://kelan.io

require 'date'

# Config values
podcast_title = "Title"
podcast_description = "Description"
public_url_base = "put_the_remote_file_url_here"


# Generated values
date_format = '%a, %d %b %Y %H:%M:%S %z'
podcast_pub_date = DateTime.now.strftime(date_format)
rss_archive_filename = "archive.rss"
rss_output_filename = "new.rss"

# Build the items
items_content = ""
Dir["/Path/To/Files/**/*"].each do |file|
    next if file =~ /^\./  # ignore invisible files
    next unless file =~ /\.(mp3|m4a)$/  # only use audio files

    item_pub_date = File.mtime(file)
    previous_pub_date = File.mtime(rss_archive_filename)
    next if previous_pub_date > item_pub_date

    puts "adding file: #{file}"

    item_size_in_bytes = File.size(file).to_s
    item_title = File.basename(file, '.m4a')
    item_url = "#{public_url_base}"
    item_content = <<-HTML
        <item>
            <title>#{item_title}</title>
            <enclosure url="#{item_url}" length="#{item_size_in_bytes}" type="audio" />
            <pubDate>#{item_pub_date.strftime(date_format)}</pubDate>
        </item>
HTML

    items_content << item_content
end

# Build the whole file
content = <<-HTML
<?xml version="1.0" encoding="ISO-8859-1"?>
<rss version="2.0">
    <channel>
        <title>#{podcast_title}</title>
        <description>#{podcast_description}</description>
        <pubDate>#{podcast_pub_date}</pubDate>
#{items_content}
    </channel>
</rss>
HTML

# write it out
output_file = File.new(rss_output_filename, 'w')
output_file.write(content)
output_file.close