Class: ActionDispatch::FileHandler

Inherits:
Object
  • Object
show all
Defined in:
actionpack/lib/action_dispatch/middleware/static.rb

Overview

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` where the base path is in the root directory. For example, if the root is set to `public/`, then a request with `env` 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.

Instance Method Summary collapse

Constructor Details

#initialize(root, index: 'index', headers: {}) ⇒ FileHandler

Returns a new instance of FileHandler.


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# File 'actionpack/lib/action_dispatch/middleware/static.rb', line 16

def initialize(root, index: 'index', headers: {})
  @root          = root.chomp('/')
  @file_server   = ::Rack::File.new(@root, headers)
  @index         = index
end

Instance Method Details

#call(env) ⇒ Object


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# File 'actionpack/lib/action_dispatch/middleware/static.rb', line 48

def call(env)
  serve(Rack::Request.new(env))
end

#match?(path) ⇒ Boolean

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 Static#call).

Returns:

  • (Boolean)

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# File 'actionpack/lib/action_dispatch/middleware/static.rb', line 28

def match?(path)
  path = ::Rack::Utils.unescape_path path
  return false unless 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.force_encoding('UTF-8'.freeze))
    begin
      File.file?(path) && File.readable?(path)
    rescue SystemCallError
      false
    end

  }
    return ::Rack::Utils.escape_path(match)
  end
end

#serve(request) ⇒ Object


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# File 'actionpack/lib/action_dispatch/middleware/static.rb', line 52

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

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