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
| | # -*- encoding: binary -*-
module Rainbows
# Rack response middleware wrapping any IO-like object with an
# OS-level file descriptor associated with it. May also be used to
# create responses from integer file descriptors or existing +IO+
# objects. This may be used in conjunction with the #to_path method
# on servers that support it to pass arbitrary file descriptors into
# the HTTP response without additional open(2) syscalls
class DevFdResponse < Struct.new(:app, :to_io, :to_path)
include Rack::Utils
# Rack middleware entry point, we'll just pass through responses
# unless they respond to +to_io+ or +to_path+
def call(env)
status, headers, body = response = app.call(env)
# totally uninteresting to us if there's no body
return response if STATUS_WITH_NO_ENTITY_BODY.include?(status)
io = body.to_io if body.respond_to?(:to_io)
io ||= File.open(body.to_path, 'rb') if body.respond_to?(:to_path)
return response if io.nil?
headers = HeaderHash.new(headers)
st = io.stat
if st.file?
headers['Content-Length'] ||= st.size.to_s
headers.delete('Transfer-Encoding')
elsif st.pipe? || st.socket? # epoll-able things
if env['rainbows.autochunk']
headers['Transfer-Encoding'] = 'chunked'
headers.delete('Content-Length')
else
headers['X-Rainbows-Autochunk'] = 'no'
end
# we need to make sure our pipe output is Fiber-compatible
case env["rainbows.model"]
when :FiberSpawn, :FiberPool, :RevFiberSpawn
return [ status, headers.to_hash, Fiber::IO.new(io,::Fiber.current) ]
end
else # unlikely, char/block device file, directory, ...
return response
end
resp = dup # be reentrant here
resp.to_path = "/dev/fd/#{io.fileno}"
resp.to_io = io
[ status, headers.to_hash, resp ]
end
# called by the webserver or other middlewares if they can't
# handle #to_path
def each(&block)
to_io.each(&block)
end
# remain Rack::Lint-compatible for people with wonky systems :P
unless File.exist?("/dev/fd/0")
alias to_path_orig to_path
undef_method :to_path
end
# called by the web server after #each
def close
begin
to_io.close if to_io.respond_to?(:close)
rescue IOError # could've been IO::new()'ed and closed
end
end
end # class
end
|