wav-to-mp3.rb

#!/usr/bin/env ruby
require 'sinatra'
require 'tempfile'

set :bind, '0.0.0.0'

get '/' do
  source_url = params['q']
  puts "Downloading #{source_url} ..."
  system("wget -nc #{source_url}")
  filename = source_url.split('/')[-1]
  dest = Tempfile.new(['audio', '.mp3'])
  system("ffmpeg -y #{dest.path} -i #{filename}")

  send_file dest.path
  dest.close
end