1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
|
require 'rack/utils'
require 'active_support/core_ext/uri'
module ActionDispatch
# This middleware returns a file's contents from disk in the body response.
# When initialized it can accept an optional 'Cache-Control' header 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 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.
class FileHandler
def initialize(root, cache_control)
@root = root.chomp('/')
@compiled_root = /^#{Regexp.escape(root)}/
headers = {}
headers['Cache-Control'] = cache_control if cache_control
@file_server = ::Rack::File.new(@root, headers)
end
def match?(path)
path = unescape_path(path)
return false unless path.valid_encoding?
full_path = path.empty? ? @root : File.join(@root, escape_glob_chars(path))
paths = "#{full_path}#{ext}"
matches = Dir[paths]
match = matches.detect { |m| File.file?(m) }
if match
match.sub!(@compiled_root, '')
::Rack::Utils.escape(match)
end
end
def call(env)
path = env['PATH_INFO']
gzip_file_exists = gzip_file_exists?(path)
if gzip_file_exists && gzip_encoding_accepted?(env)
env['PATH_INFO'] = "#{path}.gz"
status, headers, body = @file_server.call(env)
headers['Content-Encoding'] = 'gzip'
headers['Content-Type'] = content_type(path)
else
status, headers, body = @file_server.call(env)
end
headers['Vary'] = 'Accept-Encoding' if gzip_file_exists
return [status, headers, body]
end
private
def ext
@ext ||= begin
ext = ::ActionController::Base.default_static_extension
"{,#{ext},/index#{ext}}"
end
end
def unescape_path(path)
URI.parser.unescape(path)
end
def escape_glob_chars(path)
path.gsub(/[*?{}\[\]]/, "\\\\\\&")
end
def content_type(path)
::Rack::Mime.mime_type(::File.extname(path), 'text/plain')
end
def gzip_encoding_accepted?(env)
env['HTTP_ACCEPT_ENCODING'] =~ /\bgzip\b/
end
def gzip_file_exists?(path)
File.exist?(File.join(@root, "#{::Rack::Utils.unescape(path)}.gz"))
end
end
# This middleware will attempt to return the contents of a file's body from
# disk in the response. If a file is not found on disk, the request will be
# delegated to the application stack. This middleware is commonly initialized
# to serve assets from a server's `public/` directory.
#
# This middleware verifies the path to ensure that only files
# living in the root directory can be rendered. A request cannot
# produce a directory traversal using this middleware. Only 'GET' and 'HEAD'
# requests will result in a file being returned.
class Static
def initialize(app, path, cache_control=nil)
@app = app
@file_handler = FileHandler.new(path, cache_control)
end
def call(env)
case env['REQUEST_METHOD']
when 'GET', 'HEAD'
path = env['PATH_INFO'].chomp('/')
if match = @file_handler.match?(path)
env["PATH_INFO"] = match
return @file_handler.call(env)
end
end
@app.call(env)
end
end
end
|
