From: Eric Wong <e@80x24.org>
To: yahns-public@yhbt.net
Subject: [PATCH 2/2] proxy_pass: send 1.0 requests to upstreams for 1.0 clients
Date: Tue, 7 Apr 2015 03:16:58 +0000 [thread overview]
Message-ID: <1428376618-13665-3-git-send-email-e@80x24.org> (raw)
In-Reply-To: <1428376618-13665-1-git-send-email-e@80x24.org>
We cannot pass trailers from upstreams to HTTP/1.0 clients without
fully-buffering the response body AND trailers before forwarding the
response header.
Of course, one of the reasons yahns exists is to support lazy
buffering, so fully-buffering up front is wasteful and hurts
latency. So instead, degrade to 1.0 requests to upstreams for
HTTP/1.0 clients, this should prevent upstreams from sending
trailers in the first place.
HTTP/1.0 clients on Rails apps may suffer, but there probably
are not too many HTTP/1.0 clients out there.
---
lib/yahns/proxy_http_response.rb | 79 ++++++++++++----------------------------
lib/yahns/proxy_pass.rb | 8 +++-
test/test_proxy_pass.rb | 22 ++++++++---
3 files changed, 47 insertions(+), 62 deletions(-)
diff --git a/lib/yahns/proxy_http_response.rb b/lib/yahns/proxy_http_response.rb
index fe0a37b..cbfc17e 100644
--- a/lib/yahns/proxy_http_response.rb
+++ b/lib/yahns/proxy_http_response.rb
@@ -58,7 +58,6 @@ module Yahns::HttpResponse # :nodoc:
have_body = !Rack::Utils::STATUS_WITH_NO_ENTITY_BODY.include?(si) &&
env[REQUEST_METHOD] != HEAD
flags = MSG_DONTWAIT
- rechunk = false
k = self.class
alive = @hs.next? && k.persistent_connections
@@ -69,18 +68,6 @@ module Yahns::HttpResponse # :nodoc:
next # do not let some upstream headers leak through
when %r{\AContent-Length\z}i
flags |= MSG_MORE if have_body && value.to_i > 0
- when %r{\ATransfer-Encoding\z}i
- if value =~ /\bchunked\b/i
- case env['HTTP_VERSION'] # this is the original client request
- when 'HTTP/1.1'
- rechunk = true
- else
- # too expensive to calculate Content-Length for HTTP/1.0
- # persistent clients, so we will drop persistence instead
- alive = false # this should already be implied
- next
- end
- end
end
res << "#{key}: #{value}\r\n"
@@ -121,18 +108,11 @@ module Yahns::HttpResponse # :nodoc:
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
- # the end. We only send HTTP/1.1 requests to the upstream so
- # Rack/Rails can always send streaming responses.
buf = ''
case tmp = tip.shift || req_res.kgio_tryread(0x2000, rbuf)
when String
kcar.filter_body(buf, tmp)
- unless buf.empty?
- wbuf = proxy_write(wbuf, rechunk ? chunk_out(buf) : buf, alive)
- end
+ wbuf = proxy_write(wbuf, chunk_out(buf), alive) unless buf.empty?
when nil # premature EOF
return proxy_err_response(nil, req_res, nil, wbuf)
when :wait_readable
@@ -144,22 +124,19 @@ module Yahns::HttpResponse # :nodoc:
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)
+ 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
@@ -187,12 +164,6 @@ module Yahns::HttpResponse # :nodoc:
end while len != 0
else # nasty chunked body
-
- # Only HTTP/1.1 supports chunked responses, we must translate
- # otherwise. Otherwise, we must drop the connection to signal
- # the end. We only send HTTP/1.1 requests to the upstream so
- # Rack/Rails can always send streaming responses.
- rechunk = @hs.env['HTTP_VERSION'] == 'HTTP/1.1'.freeze
buf = ''
unless req_res.proxy_trailers
@@ -200,7 +171,7 @@ module Yahns::HttpResponse # :nodoc:
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)
+ buf.empty? or wbuf.wbuf_write(self, chunk_out(buf))
when nil # premature EOF
return proxy_err_response(nil, req_res, nil, wbuf)
when :wait_readable
@@ -211,19 +182,17 @@ module Yahns::HttpResponse # :nodoc:
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))
+ 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
busy = wbuf.busy and return proxy_busy_mod_blocked(wbuf, busy)
diff --git a/lib/yahns/proxy_pass.rb b/lib/yahns/proxy_pass.rb
index 3812dbf..e3ba7f0 100644
--- a/lib/yahns/proxy_pass.rb
+++ b/lib/yahns/proxy_pass.rb
@@ -205,7 +205,13 @@ class Yahns::ProxyPass # :nodoc:
req = @path.gsub(/\$(\w+)/) { req.__send__($1) }
# start the connection asynchronously and early so TCP can do a
- req = "#{env['REQUEST_METHOD']} #{req} HTTP/1.1\r\n" \
+ case ver = env['HTTP_VERSION']
+ when 'HTTP/1.1' # leave alone, response may be chunked
+ else # no chunking for HTTP/1.0 and HTTP/0.9
+ ver = 'HTTP/1.0'.freeze
+ end
+
+ req = "#{env['REQUEST_METHOD']} #{req} #{ver}\r\n" \
"X-Forwarded-For: #{env["REMOTE_ADDR"]}\r\n"
# pass most HTTP_* headers through as-is
diff --git a/test/test_proxy_pass.rb b/test/test_proxy_pass.rb
index 943fb35..c1539f8 100644
--- a/test/test_proxy_pass.rb
+++ b/test/test_proxy_pass.rb
@@ -86,13 +86,23 @@ class TestProxyPass < Testcase
delay = $1.to_f
chunky = Object.new
chunky.instance_variable_set(:@delay, delay)
- def chunky.each
- sleep @delay
- yield "3\r\nHI!\r\n"
- sleep @delay
- yield "0\r\n\r\n"
+ if env['HTTP_VERSION'] == 'HTTP/1.0'
+ h = [ %w(Content-Type text/pain), %w(Content-Length 3) ]
+ def chunky.each
+ %w(H I !).each do |x|
+ sleep @delay
+ yield x
+ end
+ end
+ else
+ h = [ %w(Content-Type text/pain), %w(Transfer-Encoding chunked) ]
+ def chunky.each
+ sleep @delay
+ yield "3\r\nHI!\r\n"
+ sleep @delay
+ yield "0\r\n\r\n"
+ end
end
- h = [ %w(Content-Type text/pain), %w(Transfer-Encoding chunked) ]
[ 200, h, chunky ]
else
[ 200, h, [ "hi\n"] ]
--
EW
prev parent reply other threads:[~2015-04-07 3:17 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-07 3:16 [PATCH 0/2] proxy_pass: fleshing out trailer support Eric Wong
2015-04-07 3:16 ` [PATCH 1/2] proxy_pass: preliminary support for passing trailers Eric Wong
2015-04-07 3:16 ` Eric Wong [this message]
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