Re: Semantics of absent header field versus header field with empty value

HTTP permits it, yes. It's considered questionable practice, though, because some implementations might not be able to make the distinction, and/or strip empty fields from the section.

Cheers,


> On 1 Mar 2022, at 10:30 am, Backman, Annabelle <richanna@amazon.com> wrote:
> 
> In light of the discussion regarding support for absent header fields in HTTP Message Signatures, I'd like to ask the perhaps obvious question: does HTTP permit header fields to make a semantic distinction between the header field being absent from a message, and the header field being present with field value equal to the empty string? If so, are there real-world use cases that people are aware of for this that might help inform that discussion?
> 
> Thanks!
> 
> —
> Annabelle Backman (she/her)
> richanna@amazon.com
> 
> 
> 
> 

--
Mark Nottingham   https://www.mnot.net/

Received on Monday, 28 February 2022 23:58:04 UTC