W3C home > Mailing lists > Public > ietf-http-wg@w3.org > April to June 2011

Re: Whitespace before responses

From: Willy Tarreau <w@1wt.eu>
Date: Thu, 30 Jun 2011 01:34:55 +0200
To: Mark Nottingham <mnot@mnot.net>
Cc: httpbis Group <ietf-http-wg@w3.org>
Message-ID: <20110629233455.GA25910@1wt.eu>
On Thu, Jun 30, 2011 at 09:12:49AM +1000, Mark Nottingham wrote:
> <http://tools.ietf.org/html/draft-ietf-httpbis-p1-messaging-14#section-3.1> says:
> 
>    In the interest of robustness, servers SHOULD ignore at least one
>    empty line received where a Request-Line is expected.  In other
>    words, if the server is reading the protocol stream at the beginning
>    of a message and receives a CRLF first, it SHOULD ignore the CRLF.
> 
> Should a similar approach be taken when clients parse responses?

While I have done it in haproxy, I don't think it really adds any value,
as I don't remember having even seen a server emit extra CRLFs after a
response.

That said, skipping leading CRLFs can be quite cheap but can bring a new
issue for browsers who try to detect HTTP/0.9 responses.

Probably that we should check if any client implementation supports it
first, and decide not to take this approach if nobody does it right now ?

> See also:
>   https://bugzilla.mozilla.org/show_bug.cgi?id=668168

Well, to be fair, I don't really catch the relation between this and
packet boundaries as discussed in this bug report. In my opinion, those
are two orthogonal things.

Regards,
Willy
Received on Wednesday, 29 June 2011 23:35:35 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Friday, 27 April 2012 06:51:42 GMT