From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1NHzxT-0006of-UN
	for qemu-devel@nongnu.org; Tue, 08 Dec 2009 08:18:27 -0500
Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43)
	id 1NHzxN-0006eG-0d
	for qemu-devel@nongnu.org; Tue, 08 Dec 2009 08:18:27 -0500
Received: from [199.232.76.173] (port=33943 helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1NHzxM-0006e2-QR
	for qemu-devel@nongnu.org; Tue, 08 Dec 2009 08:18:20 -0500
Received: from mail-gx0-f223.google.com ([209.85.217.223]:52445)
	by monty-python.gnu.org with esmtp (Exim 4.60)
	(envelope-from <anthony@codemonkey.ws>) id 1NHzxM-0005ZT-GN
	for qemu-devel@nongnu.org; Tue, 08 Dec 2009 08:18:20 -0500
Received: by gxk23 with SMTP id 23so2898249gxk.2
	for <qemu-devel@nongnu.org>; Tue, 08 Dec 2009 05:18:15 -0800 (PST)
Message-ID: <4B1E5213.1070502@codemonkey.ws>
Date: Tue, 08 Dec 2009 07:18:11 -0600
From: Anthony Liguori <anthony@codemonkey.ws>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] Re: [FOR 0.12 PATCH 18/18] QMP: add human-readable
	description to error response
References: <1260218236-22143-1-git-send-email-armbru@redhat.com>	<1260218236-22143-19-git-send-email-armbru@redhat.com>
	<20091208101148.119bed20@doriath>
In-Reply-To: <20091208101148.119bed20@doriath>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Luiz Capitulino <lcapitulino@redhat.com>
Cc: aliguori@us.ibm.com, Markus Armbruster <armbru@redhat.com>, qemu-devel@nongnu.org

Luiz Capitulino wrote:
> On Mon,  7 Dec 2009 21:37:16 +0100
> Markus Armbruster <armbru@redhat.com> wrote:
>
>   
>> -{ "error": { "class": json-string, "data": json-value }, "id": json-value }
>> +{ "error": { "class": json-string, "data": json-value, "desc": json-string },
>> +  "id": json-value }
>>  
>>   Where,
>>  
>>  - The "class" member contains the error class name (eg. "ServiceUnavailable")
>>  - The "data" member contains specific error data and is defined in a
>>    per-command basis, it will be an empty json-object if the error has no data
>> +- The "desc" member is a human-readable error message.  Clients should
>> +  not attempt to parse this message.
>>  - The "id" member contains the transaction identification associated with
>>    the command execution (if issued by the Client)
>>     
>
>  As we've talked on irc, I don't agree with this change.
>
>  Basically, adding 'desc' to the standard error message introduces all
> the problems we've discussed about free-form English strings.
>   

It's not free form English.  The 'desc' string is always autogenerated 
based on the error object.

It's completely redundant information because you can already generate 
that string, but it simplifies client creation because a lazy client 
does not have to include the conversion table if they only care about 
English error output.

Regards,

Anthony Liguori