Re: draft-ietf-httpbis-header-structure: handling multiple field values

Willy Tarreau <w@1wt.eu> Tue, 12 May 2020 17:47 UTC

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Date: Tue, 12 May 2020 19:46:29 +0200
From: Willy Tarreau <w@1wt.eu>
To: Ian Clelland <iclelland@google.com>
Cc: Julian Reschke <julian.reschke@gmx.de>, HTTP Working Group <ietf-http-wg@w3.org>
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Subject: Re: draft-ietf-httpbis-header-structure: handling multiple field values
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On Tue, May 12, 2020 at 01:39:18PM -0400, Ian Clelland wrote:
> This is mentioned in
> https://httpwg.org/http-extensions/draft-ietf-httpbis-header-structure.html#rfc.section.4.2
> --
> "parsers MUST combine all lines in the same section (header or trailer)
> that case-insensitively match the field name into one comma-separated
> field-value", (with the warning given that strings split across multiple
> field values will have "unpredictable results") -- So I don't think you're
> allowed to parse them separately. If both exist in the same message, they
> must be combined before parsing.

Thanks, so the behavior is indeed well defined and easy to enforce.

Willy