class ActionDispatch::FileHandler

Parent:: Object

This middleware returns a file's contents from disk in the body response. When initialized, it can accept optional HTTP headers, which will be set when a response containing a file's contents is delivered.

This middleware will render the file specified in env["PATH_INFO"] where the base path is in the root directory. For example, if the root is set to public/, then a request with env["PATH_INFO"] of assets/application.js will return a response with the contents of a file located at public/assets/application.js if the file exists. If the file does not exist, a 404 “File not Found” response will be returned.

Public Class Methods

new(root, index: "index", headers: {}) Show source

# File actionpack/lib/action_dispatch/middleware/static.rb, line 18
def initialize(root, index: "index", headers: {})
  @root          = root.chomp("/").b
  @file_server   = ::Rack::File.new(@root, headers)
  @index         = index
end

Public Instance Methods

call(env) Show source

# File actionpack/lib/action_dispatch/middleware/static.rb, line 49
def call(env)
  serve(Rack::Request.new(env))
end

match?(path) Show source

# File actionpack/lib/action_dispatch/middleware/static.rb, line 30
def match?(path)
  path = ::Rack::Utils.unescape_path path
  return false unless ::Rack::Utils.valid_path? path
  path = ::Rack::Utils.clean_path_info path

  paths = [path, "#{path}#{ext}", "#{path}/#{@index}#{ext}"]

  if match = paths.detect { |p|
    path = File.join(@root, p.b)
    begin
      File.file?(path) && File.readable?(path)
    rescue SystemCallError
      false
    end
  }
    return ::Rack::Utils.escape_path(match).b
  end
end

Takes a path to a file. If the file is found, has valid encoding, and has correct read permissions, the return value is a URI-escaped string representing the filename. Otherwise, false is returned.

Used by the Static class to check the existence of a valid file in the server's public/ directory (see ActionDispatch::Static#call).

serve(request) Show source

# File actionpack/lib/action_dispatch/middleware/static.rb, line 53
def serve(request)
  path      = request.path_info
  gzip_path = gzip_file_path(path)

  if gzip_path && gzip_encoding_accepted?(request)
    request.path_info           = gzip_path
    status, headers, body       = @file_server.call(request.env)
    if status == 304
      return [status, headers, body]
    end
    headers["Content-Encoding"] = "gzip"
    headers["Content-Type"]     = content_type(path)
  else
    status, headers, body = @file_server.call(request.env)
  end

  headers["Vary"] = "Accept-Encoding" if gzip_path

  [status, headers, body]
ensure
  request.path_info = path
end