自分用アレゲ画像キャッシュプロキシ

cache_proxy.rb

#!/usr/bin/env ruby

require 'fileutils'
require 'digest/sha2'
require 'webrick'
require 'webrick/httpproxy'

HOST_REGEX = [<HOST>]
PATH_REGEX = {/gif$/ => 'image/gif', /jpe??g$/ => 'image/jpeg', /png$/ => 'image/png'}

BIND_ADDR = '<IP>'
PORT = 8080

class CacheProxy < WEBrick::HTTPProxyServer
  def proxy_service(req, res)
    match_host = false
    HOST_REGEX.each do |v|
      if req.host.match(v) then
        match_host = true
        break
      end
    end

    if !match_host then
      super(req, res)
      return
    end

    match_path_mime = nil
    match_path = false
    PATH_REGEX.each do |k, v|
      if req.path.match(k) then
        match_path = true
        match_path_mime = v
        break
      end
    end

    if !match_path then
      super(req, res)
      return
    end

    puts req.host + req.path

    hash = Digest::SHA256.hexdigest(req.path)
    path_ = 'cache/%s' % req.host.gsub('/', '')
    path = '%s/%s' % [path_, hash]

    if File.exists?(path) then
      puts 'Using %s' % path
      puts

      data = IO.binread(path)
      res.status = 200
      res.content_type = match_path_mime
      res.body = data

      return
    end

    super(req, res)

    FileUtils.mkdir_p(path_)
    IO.binwrite(path, res.body)
    puts 'Cached to %s' % path
    puts
  end
end

config = { :BindAddress => BIND_ADDR, :Port => PORT, :AccessLog => [], :DoNotReverseLookup => true }
s = CacheProxy.new( config )
Signal.trap('INT') do
  s.shutdown
end
s.start