find.rb

require 'sinatra'
# require 'kramdown'

def files(regex, dir=".")
  Dir.chdir(dir) do
    ret = Dir[regex].inject([]) {|acc, f| acc << f}
    Dir["*/"].inject(ret) {|acc, f| acc << {f => files(regex, f)}}
  end
end

get "/:file" do
  file = params[:file]
  Dir.chdir Dir.pwd do
    if File.exists?(file)
      File.open(file).read
    else
      "no such file: #{Dir.pwd}/#{file}"
    end
  end
end