Class: CarbonCopy::RequestCacher

Inherits:
Object
  • Object
show all
Defined in:
lib/carbon-copy/request_cacher.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(base_dir) ⇒ RequestCacher

Returns a new instance of RequestCacher.



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# File 'lib/carbon-copy/request_cacher.rb', line 8

def initialize(base_dir)
  @base_dir = base_dir
end

Instance Attribute Details

#base_dir ⇒ Object (readonly)

Returns the value of attribute base_dir.



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# File 'lib/carbon-copy/request_cacher.rb', line 6

def base_dir
  @base_dir
end

Instance Method Details

#cache_dir ⇒ Object

Setup cache directory



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# File 'lib/carbon-copy/request_cacher.rb', line 13

def cache_dir
  "#{@base_dir}/.request_cache"
end

#connect(request) ⇒ Object 



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# File 'lib/carbon-copy/request_cacher.rb', line 70

def connect(request)
  verify_cached_dir(request)
  cached_path = path(request)

  if File.exist?(cached_path) && !File.zero?(cached_path)
    puts "Getting file #{cached_path} from cache"
    IO.read(cached_path)
  else
    resp = get_response(request)
    File.open(cached_path, "w") do |f|
      f.puts resp
    end
    resp
  end
end

#get_response(request) ⇒ Object 



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# File 'lib/carbon-copy/request_cacher.rb', line 38

def get_response(request)
  a = TCPSocket.new(request.host, request.port)
  a.write(request.request)

  # Pull request data
  content_len = nil
  buff = ""
  loop do
    line = a.readline
    buff += line
    if line =~ /^Content-Length:\s+(\d+)\s*$/
      content_len = $1.to_i
    end
    break if line.strip.empty?
  end

  # Pull response
  if content_len
    buff += a.read(content_len)
  else
    loop do
      if a.eof? || line = a.readline || line.strip.empty?
        break
      end
      buff += line
    end
  end
  a.close

  buff
end

#path(request) ⇒ Object

Determine final path



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# File 'lib/carbon-copy/request_cacher.rb', line 18

def path(request)
  uri = request.uri == "/" ? "" : request.uri.tr("\/", "_")
  hash = Digest::MD5.new << request.header_str
  # Cache directory structure
  """
    #{cache_dir}/
      #{request.host}/
        #{request.verb.downcase}
        #{uri}_
        #{hash}
  """.gsub(/\n|\s/, "")
end

#verify_cached_dir(request) ⇒ Object

Ensure cached directories are created



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# File 'lib/carbon-copy/request_cacher.rb', line 32

def verify_cached_dir(request)
  FileUtils.mkdir_p(cache_dir) unless File.exist?(cache_dir)
  host_cache = "#{cache_dir}/#{request.host}"
  FileUtils.mkdir_p(host_cache) unless File.exist?(host_cache)
end