Rack apps may (through a round-about way) send HTTP trailers
to HTTP/1.1 clients, and we need a way to forward those responses
through without losing the trailers.
---
lib/yahns/proxy_http_response.rb | 81 ++++++++++++++++++++++++++++++----------
lib/yahns/proxy_pass.rb | 1 +
test/test_proxy_pass.rb | 62 +++++++++++++++++++++++++++++-
3 files changed, 123 insertions(+), 21 deletions(-)
diff --git a/lib/yahns/proxy_http_response.rb b/lib/yahns/proxy_http_response.rb
index 8f4790e..fe0a37b 100644
--- a/lib/yahns/proxy_http_response.rb
+++ b/lib/yahns/proxy_http_response.rb
@@ -120,6 +120,7 @@ module Yahns::HttpResponse # :nodoc:
end until len == 0
else # nasty chunked body
+ req_res.proxy_trailers = nil # define to avoid warnings for now
# Only HTTP/1.1 supports chunked responses, we must translate
# otherwise. Otherwise, we must drop the connection to signal
@@ -130,9 +131,7 @@ module Yahns::HttpResponse # :nodoc:
when String
kcar.filter_body(buf, tmp)
unless buf.empty?
- tmp = rechunk ? [ "#{buf.size.to_s(16)}\r\n", buf, "\r\n".freeze ]
- : buf
- wbuf = proxy_write(wbuf, tmp, alive)
+ wbuf = proxy_write(wbuf, rechunk ? chunk_out(buf) : buf, alive)
end
when nil # premature EOF
return proxy_err_response(nil, req_res, nil, wbuf)
@@ -142,8 +141,25 @@ module Yahns::HttpResponse # :nodoc:
return :wait_readable # self remains in :ignore, wait on upstream
end until kcar.body_eof?
- # TODO: Trailer support
- wbuf = proxy_write(wbuf, "0\r\n\r\n".freeze, alive) if rechunk
+ buf = tmp
+ req_res.proxy_trailers = [ buf, tlr = [] ]
+ rbuf = Thread.current[:yahns_rbuf] = ''
+ if rechunk
+ until kcar.trailers(tlr, buf)
+ case rv = req_res.kgio_tryread(0x2000, rbuf)
+ when String
+ buf << rv
+ when :wait_readable
+ # for ensure:
+ wbuf ||= Yahns::Wbuf.new(nil, alive, k.output_buffer_tmpdir,
+ false)
+ return :wait_readable
+ when nil # premature EOF
+ return proxy_err_response(nil, req_res, nil, wbuf)
+ end # no loop here
+ end
+ wbuf = proxy_write(wbuf, trailer_out(tlr), alive)
+ end
end
end
@@ -178,22 +194,36 @@ module Yahns::HttpResponse # :nodoc:
# Rack/Rails can always send streaming responses.
rechunk = @hs.env['HTTP_VERSION'] == 'HTTP/1.1'.freeze
buf = ''
- case tmp = req_res.kgio_tryread(0x2000, rbuf)
- when String
- kcar.filter_body(buf, tmp)
- unless buf.empty?
- tmp = rechunk ? [ "#{buf.size.to_s(16)}\r\n", buf, "\r\n".freeze ]
- : buf
- wbuf.wbuf_write(self, tmp)
- end
- when nil # premature EOF
- return proxy_err_response(nil, req_res, nil, wbuf)
- when :wait_readable
- return :wait_readable # self remains in :ignore, wait on upstream
- end until kcar.body_eof?
- # TODO: Trailer support
- wbuf.wbuf_write(self, "0\r\n\r\n".freeze) if rechunk
+ unless req_res.proxy_trailers
+ # are we done dechunking the main body, yet?
+ case tmp = req_res.kgio_tryread(0x2000, rbuf)
+ when String
+ kcar.filter_body(buf, tmp)
+ buf.empty? or wbuf.wbuf_write(self, rechunk ? chunk_out(buf) : buf)
+ when nil # premature EOF
+ return proxy_err_response(nil, req_res, nil, wbuf)
+ when :wait_readable
+ return :wait_readable # self remains in :ignore, wait on upstream
+ end until kcar.body_eof?
+ req_res.proxy_trailers = [ tmp, [] ] # onto trailers!
+ rbuf = Thread.current[:yahns_rbuf] = ''
+ end
+
+ buf, tlr = *req_res.proxy_trailers
+ if rechunk
+ until kcar.trailers(tlr, buf)
+ case rv = req_res.kgio_tryread(0x2000, rbuf)
+ when String
+ buf << rv
+ when :wait_readable
+ return :wait_readable
+ when nil # premature EOF
+ return proxy_err_response(nil, req_res, nil, wbuf)
+ end # no loop here
+ end
+ wbuf.wbuf_write(self, trailer_out(tlr))
+ end
end
busy = wbuf.busy and return proxy_busy_mod_blocked(wbuf, busy)
@@ -226,4 +256,15 @@ module Yahns::HttpResponse # :nodoc:
# no touching self after queue_mod
:ignore
end
+
+ # n.b.: we can use String#size for optimized dispatch under YARV instead
+ # of String#bytesize because all the IO read methods return a binary
+ # string when given a maximum read length
+ def chunk_out(buf)
+ [ "#{buf.size.to_s(16)}\r\n", buf, "\r\n".freeze ]
+ end
+
+ def trailer_out(tlr)
+ "0\r\n#{tlr.map! do |k,v| "#{k}: #{v}\r\n" end.join}\r\n"
+ end
end
diff --git a/lib/yahns/proxy_pass.rb b/lib/yahns/proxy_pass.rb
index ec1fbcf..3812dbf 100644
--- a/lib/yahns/proxy_pass.rb
+++ b/lib/yahns/proxy_pass.rb
@@ -12,6 +12,7 @@ require_relative 'proxy_http_response'
class Yahns::ProxyPass # :nodoc:
class ReqRes < Kgio::Socket
attr_writer :resbuf
+ attr_accessor :proxy_trailers
def req_start(c, req, input, chunked)
@hdr = @resbuf = nil
diff --git a/test/test_proxy_pass.rb b/test/test_proxy_pass.rb
index 47fc231..943fb35 100644
--- a/test/test_proxy_pass.rb
+++ b/test/test_proxy_pass.rb
@@ -53,6 +53,33 @@ class TestProxyPass < Testcase
io = env['rack.hijack'].call
io.write(TRUNCATE_HEAD)
io.close
+ when '/response-trailer'
+ h = [
+ %w(Content-Type text/pain),
+ %w(Transfer-Encoding chunked),
+ %w(Trailer Foo)
+ ]
+ b = [ "3\r\n", "hi\n", "\r\n", "0\r\n", "Foo: bar", "\r\n", "\r\n" ]
+ case env['HTTP_X_TRAILER']
+ when 'fast'
+ b = [ b.join ]
+ when 'allslow'
+ def b.each
+ size.times do |i|
+ sleep 0.1
+ yield self[i]
+ end
+ end
+ when /\Atlrslow(\d+)/
+ b.instance_variable_set(:@yahns_sleep_thresh, $1.to_i)
+ def b.each
+ size.times do |i|
+ sleep(0.1) if i > @yahns_sleep_thresh
+ yield self[i]
+ end
+ end
+ end
+ [ 200, h, b ]
when '/immediate-EOF'
env['rack.hijack'].call.close
when %r{\A/chunky-slow-(\d+(?:\.\d+)?)\z}
@@ -184,7 +211,7 @@ class TestProxyPass < Testcase
@srv.close
cfg.instance_eval do
app(:rack, ProxiedApp.new) do
- listen "#{host2}:#{port2}"
+ listen "#{host2}:#{port2}", rcvbuf: 4096
client_max_body_size nil
end
stderr_path err.path
@@ -192,6 +219,7 @@ class TestProxyPass < Testcase
end
check_pipelining(host, port)
+ check_response_trailer(host, port)
gplv3 = File.open('COPYING')
@@ -434,4 +462,36 @@ class TestProxyPass < Testcase
ensure
s.close if s
end
+
+ def check_response_trailer(host, port)
+ thrs = [
+ "X-Trailer: fast\r\n",
+ "X-Trailer: allslow\r\n",
+ "X-Trailer: tlrslow1\r\n",
+ "X-Trailer: tlrslow2\r\n",
+ "X-Trailer: tlrslow3\r\n",
+ "X-Trailer: tlrslow4\r\n",
+ ''
+ ].map do |x|
+ Thread.new do
+ s = TCPSocket.new(host, port)
+ s.write "GET /response-trailer HTTP/1.1\r\n#{x}" \
+ "Host: example.com\r\n\r\n"
+ res = ''
+ buf = ''
+ Timeout.timeout(60) do
+ until res =~ /Foo: bar\r\n\r\n\z/
+ res << s.readpartial(16384, buf)
+ end
+ end
+ assert_match(%r{\r\n0\r\nFoo: bar\r\n\r\n\z}, res)
+ assert_match(%r{^Trailer: Foo\r\n}, res)
+ assert_match(%r{^Transfer-Encoding: chunked\r\n}, res)
+ assert_match(%r{\AHTTP/1\.1 200 OK\r\n}, res)
+ s.close
+ :OK
+ end
+ end
+ thrs.each { |t| assert_equal(:OK, t.value) }
+ end
end
--
EW
