A 10 minute ruby bit-torrent tracker :)

gistfile1.txt

require 'sinatra'
require "sinatra/reloader" 

PEER_DICT = Hash.new { |h,k| h[k] = {} }


class Hash
  def bencode
    [
      "d",
      map { |k,v| [k.to_s.bencode, v.bencode] },
      "e"
    ].join('')
  end
end
class Symbol
  def bencode
    to_s.bencode
  end
end
class String
  def bencode
    "#{length}:#{to_s}"
  end
end
class Fixnum
  def bencode
    "i#{to_s}e"
  end
end
class Array
  def bencode
    [
      "l",
      map { |v| v.bencode },
      "e"
    ].flatten.join('')
  end
end

# puts "Thomas".bencode
# puts 1234.bencode
# puts [1,2,3,4].bencode
# puts({"a" => 123}.bencode)
# puts({"a" => [1,2,{"b" => :c}, [4,5,6]]}.bencode)

# exit(0)

get '/announce' do

  info_hash = params['info_hash']
  info_hash_disp = info_hash.unpack("C*")[0,20].map { |i| "%02x" % i }.join(" ")
  peer_id = params['peer_id']
  peer_id_disp = peer_id.unpack("C*")[0,20].map { |i| "%02x" % i }.join(" ")
  port = params['port'].to_i
  ip = params['ip'] || request.ip

  event = params['event']

  if event == 'started'
    PEER_DICT[info_hash][peer_id] = [ip, port]
  elsif event == 'stopped'
    PEER_DICT[info_hash].delete(peer_id)
  end

  puts "Got annoucement '#{event}'"
  puts "Info hash is #{info_hash_disp}"
  puts "Peer id is   #{peer_id_disp}"
  puts "Port is      #{port}"

  puts "Remote IP is #{ip}" 


  puts "This info hash has #{PEER_DICT[info_hash].values.size} peers"

  content_type 'text/plain'
  p response = {
    "interval"    => 2,
    "complete"    => 10,
    "incomplete"  => 20,
    "tracker_id"  => "tracker-id",
    "peers" => PEER_DICT[info_hash].map { |peer_id,params| 
      ip, port = params
      { "peer_id" => peer_id, "ip" => ip, "port" => port }
    }
  }.bencode
end


get '/scrape' do

  puts "SCRAPE!"
end