Re: [ftpext] Soliciting comments/reviews on draft-yevstifeyev-ftp-uri-scheme

Daniel Stenberg <daniel@haxx.se> Sun, 22 May 2011 17:58 UTC

Return-Path: <daniel@haxx.se>
X-Original-To: ftpext@ietfa.amsl.com
Delivered-To: ftpext@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id DFD73E06CF; Sun, 22 May 2011 10:58:38 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.249
X-Spam-Level:
X-Spam-Status: No, score=-2.249 tagged_above=-999 required=5 tests=[BAYES_00=-2.599, HELO_EQ_SE=0.35]
Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id k0K5ZiJeXvOE; Sun, 22 May 2011 10:58:38 -0700 (PDT)
Received: from giant.haxx.se (giant.haxx.se [80.67.6.50]) by ietfa.amsl.com (Postfix) with ESMTP id CA5DBE06A0; Sun, 22 May 2011 10:58:35 -0700 (PDT)
Received: from giant.haxx.se (giant.haxx.se [80.67.6.50]) by giant.haxx.se (8.14.4/8.14.4/Debian-2) with ESMTP id p4MHjib2003426; Sun, 22 May 2011 19:45:44 +0200
Date: Sun, 22 May 2011 19:45:44 +0200
From: Daniel Stenberg <daniel@haxx.se>
X-X-Sender: dast@giant.haxx.se
To: Mykyta Yevstifeyev <evnikita2@gmail.com>
In-Reply-To: <4DD89A18.3090105@gmail.com>
Message-ID: <alpine.DEB.2.00.1105221515140.5566@tvnag.unkk.fr>
References: <4DD89A18.3090105@gmail.com>
User-Agent: Alpine 2.00 (DEB 1167 2008-08-23)
X-fromdanielhimself: yes
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; format="flowed"; charset="US-ASCII"
X-Greylist: Default is to whitelist mail, not delayed by milter-greylist-4.3.8 (giant.haxx.se [80.67.6.50]); Sun, 22 May 2011 19:45:44 +0200 (CEST)
Cc: "uri-review@ietf.org" <uri-review@ietf.org>, ftpext@ietf.org
Subject: Re: [ftpext] Soliciting comments/reviews on draft-yevstifeyev-ftp-uri-scheme
X-BeenThere: ftpext@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: <ftpext.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ftpext>, <mailto:ftpext-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/ftpext>
List-Post: <mailto:ftpext@ietf.org>
List-Help: <mailto:ftpext-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ftpext>, <mailto:ftpext-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sun, 22 May 2011 17:58:39 -0000

On Sun, 22 May 2011, Mykyta Yevstifeyev wrote:

> I'm writing to ask people to comment my draft 
> draft-yevstifeyev-ftp-uri-scheme, that may be found here:

Hi

I think the document looks fine and basically repeats what RFC1738 says. It 
would be really helpful if it would mention where or how it differs from 
RFC1738.

My concern is "The <ftp-path> Part", section 2.2.3, and the problems aren't 
really introduced by you but repeating existing problems in a brand new 
document seems a bit unnecessary.

The original problem I have with this exists already in RFC1738 as it mandates 
a CWD command for each <cwd> part of the path. There are lots of servers out 
in the wild who are configured to not allow this, but yet allows the client to 
do a single CWD to the entire path. That means "CWD dir1/dir2" works while 
"CWD dir1" fails. We can of course just consider such servers as non-compliant 
but clients may still need to consider this (and I know lots of clients only 
do the CWD <full path> approach).

The next problem in the same section is what to do with empty <cwd> parts. As 
in "ftp://example.com/path1//path2". RFC1738 acknowledges that the <cwd> parts 
may be empty. It continues to say that each <cwd> should result as an argument 
to CWD. But lots of FTP servers will treat "CWD" with a blank argument similar 
to what unix machines does with 'cd' without a directory: it changes directory 
to a pre-determined location (home directory) that certainly is not at all 
what the client wants for this. A "normal" FTP client will therefore not issue 
a separate CWD for empty parts.

In draft-yevstifeyev-ftp-uri-scheme there's no mention of the fact that <cwd> 
can be empty (which isn't really solving how to deal with them) but there's a 
similar mention that each <cwd> should be passed on to CWD.

-- 

  / daniel.haxx.se