module Middleman::CoreExtensions::Request::InstanceMethods

def send_file(resource, env)
  file      = ::Rack::File.new nil
  file.path = resource.source_file
  response = file.serving(env)
  status = response[0]
  response[1]['Content-Encoding'] = 'gzip' if %w(.svgz .gz).include?(resource.ext)
  # Do not set Content-Type if status is 1xx, 204, 205 or 304, otherwise
  # Rack will throw an error (500)
  if !(100..199).include?(status) && ![204, 205, 304].include?(status)
    response[1]['Content-Type'] = resource.content_type || "application/octet-stream"
  end
  halt response
end