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RE: Question about XML Schema validation

From: Mark Birbeck <mark.birbeck@x-port.net>
Date: Thu, 9 Jun 2005 11:45:29 +0100
Message-ID: <783605C1-5F6C-438C-BC49-53E52231C937@S009>
To: "'John Boyer'" <JBoyer@PureEdge.com>, "'Erik Bruchez'" <erik@bruchez.org>, <www-forms@w3.org>

Hi John and Eric,

I thought it would be a useful exercise to try to summarise in one place
everything that I could find on validation, from the 1.0 and errata


It would be helpful if anyone who is interested in this could cast their
eyes over it and see if there is anything that should be
added/removed/explained better, etc.

During the course of doing this, one thing jumped out which is that the spec
says events like xforms-readwrite, xforms-enabled and so on, are dispatched
during xforms-revalidate (see section 4.3.5, step 3). However, the MIPs that
correspond to these events are not themselves calculated here, but in
xforms-recalculate, so there is no way that these events can be fired at
this time. (Also, the event is cancellable, which means you'd lose events
like xforms-optional, which have nothing to do with validity.)

Probably another errata candidate? ;)



Mark Birbeck
x-port.net Ltd.

e: Mark.Birbeck@x-port.net
t: +44 (0) 20 7689 9232
w: http://www.formsPlayer.com/
b: http://internet-apps.blogspot.com/

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> -----Original Message-----
> From: www-forms-request@w3.org 
> [mailto:www-forms-request@w3.org] On Behalf Of John Boyer
> Sent: 08 June 2005 17:16
> To: Erik Bruchez; www-forms@w3.org
> Subject: RE: Question about XML Schema validation
> Hi Eric,
> Yes, the validity of a node comes from the following channels:
> 1) defined schema related to the node (which also implies the 
> type MIP)
> 2) required
> 3) constraint MIP
> (assuming the node is relevant, of course).
> See Section 4.3.5, the xforms-revalidate event.
> Cheers,
> John Boyer
> -----Original Message-----
> From: www-forms-request@w3.org [mailto:www-forms-request@w3.org]On
> Behalf Of Erik Bruchez
> Sent: Wednesday, June 08, 2005 3:09 AM
> To: www-forms@w3.org
> Subject: Re: Question about XML Schema validation
> John Boyer wrote:
>  > Hi Erik,
>  >
>  > The erratum is erroneous, and the working group is 
> actively working  > on it.
>  >
>  > The issue has been thoroughly discussed on our last 
> telecon, and its  > resolution is scheduled for our face to 
> face meeting next week.
>  >
>  > I expect there will be some kind of change in what E29 says.
> Thanks.
> Another question I have regards validity and how it relates 
> to the "required" model item property, if at all.
> It seems that "required" mainly impacts submission (according to
> 6.1.3: "indicates that a non-empty instance data node is 
> required before a submission of instance data can occur"). 
> Plus, a control bound to required node may have some visual feedback.
> So far, so good, except that the section on submission is a little
> fuzzy: "Any selected instance data found to be *invalid* 
> stops submit processing...". Definition of "invalid instance 
> data" is not clear. Does this include checking for 
> "required"? 6.1.3 appears to say so, but then it's not 
> validity, it's being required! However, this suggests that in 
> somebody's mind, "valid" is tied to "required".
> An example:
> If you say that an "instance data node" (BTW "instance data node"
> doesn't have a definition in the spec as far as I can tell) 
> is bound to, say, a type "xs:date", and if it is not 
> required, does the node become valid, or invalid? It seems to 
> me that according to the spec the properties on the node will be:
> o valid: false()
> o required: false() (default)
> Is this the intended result? Should then the UI and controls 
> be in charge of marking the node as "invalid" for the user by 
> combining those two model item properties?
> Intuitively, I would have imagined that "required" would influence
> "valid": if a node would be otherwise invalid as per a bound 
> type, but is actually empty and not required, then it is no 
> longer invalid.
> Am I the only one confused?
> -Erik
Received on Thursday, 9 June 2005 10:46:00 UTC

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