On Tue, Oct 12, 2021 at 10:26:22AM +0200, Alexey Abramov via Bug reports for GUILE, GNU's Ubiquitous Extension Language wrote:
> Hi,
> 
> I agree that it is not a complient http response,

According to The Book [1] ;-) there should be at least one
space (SP) (as far as I understand this is really a true
honest space, Unicode codepoint 32. It is /not/ part of the
message (aka "reason phrase") , but a separator. The rule
is:

  status-line = HTTP-version SP status-code SP reason-phrase CRLF

The reason phrase itself can contain whatever funny whitespace
it wants:

  reason-phrase  = *( HTAB / SP / VCHAR / obs-text )

and it /can/ be empty.

That said I'd agree that it makes sense to tolerate a missing
SP there. The legal minimum seems thus to be

  HTTP-version SP status-code SP CRLF

>                                          but unfortunately I
> came across with some http services (redfish, cimc from Cisco )

uh-oh. All bets are off, then ;-)


> where they don't put a reason phrase.

That would be OK, but they also eat the mandatory separator space
before the empty reason phrase. Bad folks, bad ;-)

As an onlooker I haven't much to say, but I think you are right
(but not Cisco :)

Cheers
 - t