code review 1610042: http: reply to Expect 100-continue requests automatically

http: reply to Expect 100-continue requests automatically

This CL replaces my earlier http://codereview.appspot.com/1640044/show
in which Continue handling was explicit.  Instead, this CL makes
it automatic.  Reading from Body() is an implicit acknowledgement
that the request headers were fine and the body is wanted.  In that
case, the 100 Continue response is written automatically when the
request continues the "Expect: 100-continue" header.

[brad_danga_com, 2010-06-12 21:06:38]

Hello rsc (cc: golang-dev@googlegroups.com),

I'd like you to review this change.

[adg, 2010-06-13 07:14:17]

http://codereview.appspot.com/1610042/diff/2001/3002
File src/pkg/http/server.go (right):

http://codereview.appspot.com/1610042/diff/2001/3002#newcode59
src/pkg/http/server.go:59: wroteContinue   bool              // 100 Continue
response was written
With the wroteContinueReader, do we still need this flag?

http://codereview.appspot.com/1610042/diff/2001/3002#newcode88
src/pkg/http/server.go:88: ecr.conn.writeContinueResponse()
instead of calling this function, why not just replace with this code:

ecr.conn.wroteContinue = true
if ecr.conn.Req.ProtoAtLeast(1, 1) {
     io.WriteString(ecr.conn.buf, "HTTP/1.1 100 Continue\r\n\r\n")
     ecr.conn.buf.Flush()
}

http://codereview.appspot.com/1610042/diff/2001/3002#newcode193
src/pkg/http/server.go:193: func (c *Conn) writeContinueResponse() {
If this function is only called from the Read method of expectsContinueReader,
then most of it is redundant, as it won't be called if either c.hijacked or
c.wroteContinue are true.

[brad_danga_com, 2010-06-13 16:17:25]

Hello rsc, adg (cc: golang-dev@googlegroups.com),

Please take another look.

[adg, 2010-06-16 08:03:41]

LGTM

Russ?

On 13 June 2010 18:17,  <bradfitz@gmail.com> wrote:
> Hello rsc, adg (cc: golang-dev@googlegroups.com),
>
> Please take another look.
>
>
> http://codereview.appspot.com/1610042/show
>

[rsc, 2010-06-16 17:13:37]

LGTM

[rsc, 2010-06-16 17:15:47]

*** Submitted as http://code.google.com/p/go/source/detail?r=4cb083009bcc ***

http: reply to Expect 100-continue requests automatically

This CL replaces my earlier http://codereview.appspot.com/1640044/show
in which Continue handling was explicit.  Instead, this CL makes
it automatic.  Reading from Body() is an implicit acknowledgement
that the request headers were fine and the body is wanted.  In that
case, the 100 Continue response is written automatically when the
request continues the "Expect: 100-continue" header.

R=rsc, adg
CC=golang-dev
http://codereview.appspot.com/1610042

Committer: Russ Cox <rsc@golang.org>