Reinhard Poetz wrote:
Sylvain Wallez wrote:
I once proposed that validators could produce a small snippet of JS that would be included in the produced page. However, this somehow mixes some client-side technology in the validators which isn't a good thing.
So the idea now is that a validator produces an XML representation of itself, which could be a simple as it's definition translated to the "fi:" namespace.
E.g.
<fd:field id="foo" required="true"> <fd:datatype base="integer"/> <fd:validation> <fd:range min="1" max="10"/> </fd:validation> </fd:field>
would produce <fi:field id="foo"> <fi:datatype type="integer"/> <fi:validation> <fi:required> <fi:range min="1" max="10"/> </fi:validation> </fi:field>
It's then the job of the presentation XSLs to transform <fi:range> into something useful.
Only those validators where a client-side implementation is possible would produce an XML fragment in the <fi:validation> element.
WDYT?
yep, that's the way to go! If widgets produced Javascript themselves, we would mix concerns because not all clients support Javascript or you need different Javascript "dialects" for different clients. Following Sylvain's proposal it's the stylesheet's job to create working valdiation programms.
We should also think of a way how and where we can add custom client-side validators. If we add this to the form defintion we would need some kind of abstract language, or at least Javascript with an abstract object model:
<ft:client-side-validation> if($widgetXY.value$ <= $widgetZZ.value$ { return "i18:value-to-high"; } return true; </ft:client-side-validation>
This could be transformed into something valid for the client by replacing the $...$-tokens through valid pointers to the client's object model.
Or simply an abstract getWidgetValue(name) function that would have different implementations server-side and client-side? That way, we don't need macro expansion and we can use a single JS snippet for both client and server-side validation.
Of course, not every JS validator can run client-side, and that needs to be distinguished with a particular attribute:
Sylvain
-- Sylvain Wallez Anyware Technologies http://www.apache.org/~sylvain http://www.anyware-tech.com { XML, Java, Cocoon, OpenSource }*{ Training, Consulting, Projects }
