Subject: #1004 USEFOR 3.2.14 - X-Headers text suggestion

From: Harald Tveit Alvestrand <[email-masked]>
Date: Tue, 14 Jun 2005 07:52:56 -0400

Ticket text and comments so far:

> From Frank Ellermann:
>
> Is deprecating X- headers allowed ?
>
> From Charles Lindsey, May 26:
>
>> Is deprecating X- headers allowed ?
>
> I don't see why not, if you are providing a standard header to fulfil
> the same role.

> From Frank Ellermann:
>
> Examples could include "X-NoArchive: yes, (c) 2005 by xyzzy"
> or "X-ComplaintsTo: not me". The "same role" is unclear for
> X- header fields.
>
> Not an important point, but if it helps to avoid a warning
> from Bruce's review tool I'd just delete the last statement
> "These headers are thus deprecated." - the intended effect of
> the complainto-param is obvious without it.

text suggestion from me:

OLD (3.2.13):

      NOTE: This header supersedes the role performed redundantly by
      experimental headers such as X-Newsreader, X-Mailer, X-Posting-
      Agent, X-Http-User-Agent, and other headers previously used on
      Usenet and in Email for this purpose.  Use of these experimental
      headers SHOULD be discontinued in favor of the single, standard
      User-Agent header.

NEW:

      NOTE: Some of this information has previously been sent in
      non-standardized headers such as X-Newsreader, X-Mailer, X-Posting-
      Agent, X-Http-User-Agent, and others.
      Once an agent uses User-Agent, it should have no need to
      send these non-standard headers.

OLD (3.2.14):

   This header is intended to replace various currently-used but
   undocumented headers such as "NNTP-Posting-Host", "X-Trace" and
   "X-Complaints-To".  These headers are thus deprecated.

NEW:

      NOTE: Some of this information has previously been sent in
      non-standardized headers such as NNTP-Posting-Host, X-trace,
      X-Complaints-To, and others.
      Once an injecting agent uses Injection-Info, it should have no need to
      send these non-standard headers.

Makes sense?

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From: Frank Ellermann <[email-masked]>
Date: Tue, 14 Jun 2005 14:11:10 +0200

> Makes sense?

Yes, good riddance of this X-header-zoo => #1004 resolved.

---

From: Alexey Melnikov <[email-masked]>
Date: Wed, 15 Jun 2005 00:24:54 +0100

>      send these non-standard headers.

One issue I should have raised earlier is about X-Mailer. X-Mailer is 
supported by majority of mail clients and is a de-facto standard for 
email. Many of those mail clients are also news clients. So I think it 
is too late (and even harmful) to deprecate X-Mailer.

>      send these non-standard headers.

The rest looks good to me.

---

From: Harald Tveit Alvestrand <[email-masked]>
Date: Wed, 15 Jun 2005 07:13:11 -0400

--On 15. juni 2005 00:24 +0100 Alexey Melnikov 
<[email-masked]> wrote:

> email. Many of those mail clients are also news clients. So I think it is
> too late (and even harmful) to deprecate X-Mailer.

We can't standardize it (due to the X- rule; see John Klensin's appeal on 
the LEMONADE MMS document on the IETF list for details).
So it's going to remain undefined with regard to format, handling rules and 
so on. And messages without it are going to continue to be acceptable, no 
matter what.

So we've got 2 options:

- Keep it on the list of "don't see why you'd continue to send it"
- Not mention it at all

I don't want to say anything that seems like *recommending* sending

User-agent: foobar/1.2
X-Mailer: foobar/1.2

That's just useless header bloat in my opinion. But just my opinion.

---

From: Alexey Melnikov <[email-masked]>
Date: Wed, 15 Jun 2005 12:33:50 +0100

Harald Tveit Alvestrand wrote:

> We can't standardize it (due to the X- rule; see John Klensin's appeal 
> on the LEMONADE MMS document on the IETF list for details).
> So it's going to remain undefined with regard to format, handling 
> rules and so on. And messages without it are going to continue to be 
> acceptable, no matter what.
>
> So we've got 2 options:
>

Considering the choices I would prefer not mentioning it.

---

From: "Charles Lindsey" <[email-masked]>
Date: Wed, 15 Jun 2005 12:12:53 GMT

>>      send these non-standard headers.

I think I prefer the original wording; or if not, something in between.
What we are trying to bring about is that User-Agent will become the norm,
and that usage of the others will fade away. If "SHOULD be discontinued"
is considered to be too strong, then something like "it is
intended/expected that ...", or "continued use of ... is discouraged". And
the word "redundant(ly)" in the original could usefully be retained, as
providing motivation for the intention/expectation/discouragement.

>is too late (and even harmful) to deprecate X-Mailer.

Again, I think the intent is that it will fade away (note that one could
never standardize it in that form). More and more user agents are using
User-Agent (though with some divergence as regards its exact syntax, which
our draft should clarify). And when you say X-Mailer is "supported",
surely what you mean is that it is "generated". I don't think much
software actually looks at it, apart from ad hoc scripts, which are going
to have to look at User-Agent as well. Indeed, the whole point of
encouraging those old headers to fade away is that eventually the writers
of ad hoc scripts will just need to look at User-Agent.

>>      send these non-standard headers.

Same remarks as for User-Agent. I prefer the Old, and if not that then
something a bit stronger than the New.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
Tel: +44 161 436 6131 Fax: +44 161 436 6133   Web: http://www.cs.man.ac.uk/~chl
Email: [email-masked]      Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, U.K.
PGP: 2C15F1A9      Fingerprint: 73 6D C2 51 93 A0 01 E7 65 E8 64 7E 14 A4 AB A5

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From: Russ Allbery <[email-masked]>
Date: Wed, 15 Jun 2005 11:12:59 -0700

> text suggestion from me:

I like this a lot better.  Deprecating X-* headers did feel a bit odd, and
I think this will accomplish the same thing in practice.

-- 
Russ Allbery ([email-masked])             <http://www.eyrie.org/~eagle/>

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From: [email-masked] (Kai Henningsen)
Date: 17 Jun 2005 09:05:00 +0200

> is too late (and even harmful) to deprecate X-Mailer.

I don't see why. (And I'm not even sure I believe that! User-Agent is  
certainly not an invention of this WG; it's copied from HTTP, and I expect  
(didn't look) that Mozilla and derived software (Thunderbird, for example)  
already support *that*.)

MfG Kai