Re: [draft-melnikov-sieve-external-lists] Proposed Changes To Section 2.3

[Barry Leiba <barryleiba.mailing.lists@xxxxxxxxx>]

I don't strongly object to the change Robert suggests, below, but I
think it's useful to explain the situation, to explain why there might
be issues here.  I'd rather not eliminate the paragraph that gives
that explanation.  I'm happier, if we want to use Robert's text, to
leave at least some of the eliminated paragraph in as an informative
note.

Barry

On Fri, Jul 24, 2009 at 5:04 AM, Robert Burrell
Donkin<robertburrelldonkin@xxxxxxxxx> wrote:
>
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> Changes
> - -------
> Revise and consolidate existing paragraphs 3 and 4 into a shorter functional
> description.
>
> Rationale
> - ---------
> Paragraphs 3 and 4 in 2.3 specify complex, hard to test requirements for
> little clear gain. Regarding the redirection as a black box makes the
> specification
> more concise and allows more space for novel approaches.
>
> - --------------------------------------------------------------------------
> [1] Proposed Text
> - --------------------------------------------------------------------------
>
> 2.3.  :list tagged argument to the "redirect" action
>
>   Usage:  redirect :list
>
>   The "redirect" action with the ":list" argument is used to send the
>   message to one or more email addresses stored in the externally
>   stored list 'ext-list-name'.  This variant of the redirect command
>   can be used to implement a personal distribution list.
>
>   The Sieve engine and list server SHOULD collaborate to achieve a
>   redirection consistent with the semantics described in [Sieve]. If
>   they are unable to do so then the situation MUST result in a
>   runtime error.
>
>   See Section 2.4 for the detailed description of syntax used for
>   naming externally stored lists.
>
> - --------------------------------------------------------------------------
> [2] Original Text
> - --------------------------------------------------------------------------
> 2.3.  :list tagged argument to the "redirect" action
>
>   Usage:  redirect :list
>
>   The "redirect" action with the ":list" argument is used to send the
>   message to one or more email addresses stored in the externally
>   stored list 'ext-list-name'.  This variant of the redirect command
>   can be used to implement a personal distribution list.
>
>   Use of this feature requires that the list resolve to a list of email
>   addresses, and that the Sieve engine be able to enumerate those
>   addresses. [[anchor5: Alexey would like the option of allowing the
>   list handler to enumerate the addresses and do the redirect there.
>   Barry thinks that's contrary to Sieve, which expects to queue the
>   redirect action for processing at a later stage, and that it would be
>   a bad idea to have the redirect happen in the list handler.  The WG
>   needs to resolve this issue.]]  In cases where, for example, a list
>   contains hashed email address values or an email address pattern
>   ("sz*@example.com", "*+ietf@xxxxxxxxxxx"), it will not be possible to
>   redirect to that list.
>
>   If the Sieve engine [[anchor6: or list handler?]] is permanently
>   unable to enumerate the list or the list does not resolve to email
>   addresses, the situation MUST result in a runtime error in the Sieve
>   script.
>
>   See Section 2.4 for the detailed description of syntax used for
>   naming externally stored lists.
>