Turn "authors" attached to blog posts into a _data file

gistfile1.rb

#! /usr/bin/ruby
require 'jekyll'
config = Jekyll.configuration
source = config['source']
data_source = File.join(source, config['data_source'])
posts = File.join(source, '_posts')
authors = []
if ARGV[0].nil?
	puts "No value passed for filename, assuming 'author.'"
	file_name = 'author'
else
	file_name = ARGV[0]
end
Dir.foreach(posts) { |p|
	if File.extname(p) == ".html" or File.extname(p) == '.md'
		yaml = YAML.load_file(File.join(posts, p))
		if yaml['author']
			yaml['author'].each { |a| authors.push(a) }
		end
		if yaml['authors']
			yaml['authors'].each { |a| authors.push(a) }
		end
	end
}
target = File.open(File.join(data_source, "#{file_name}.yml"), 'w')
target.write(YAML.dump(authors.uniq.to_yaml))