Agree. In its(TurboGears) current form, I have changed all my functions
to this form(thus ignore the validator feature) :
func(self,**kwargs):
Then I can define a formencode schema to validate against kwargs which
is a dict. Basically achieve what you mentioned. The only issue is, a
few line of code is needed to grab the keywords that is needed for
processing, back from kwargs, rather than func(self,
something=None,someother=None). But kwargs is needed anyway(as the
kitchen sink) or any strange hidden fields in a form would bomb.
Krys Wilken wrote:
> Interesting idea. :-)
>
> I am unsure what benefit it provides over just say just having an extra
> errors=None argument on the original method. I'd love to hear your
> thoughts on it though. :-)
>
> It seems to me that that there are two simple ways of handling
> validation errors:
>
> 1) Adding an errors=None argument to the method and letting it handle
> things (so the validators would just populate the errors dict and pass
> them on to the method), or
> 2) Ian's idea of an on_error='method_name' added to expose.
>
> Actually, now that I am thinking of it, I'd say combine the two ideas.
>
> If no on_error is provided assume the on_error method is the method
> being decorated, otherwise call the specified method.
>
> Whatever method is called would have and errors keyword argument which
> is a dictionary in the form of: {'form_field_name': [list of Invalid
> objects],...}
>
> That way you can have, as Ian believes, separate methods for
> presentation of a form and processing of it, or you can have one method
> responsible for both, as others prefer.
>
> In either case, the method that knows best about it's subject matter is
> responsible for handling the errors, instead of some generic
> validation_error method that knows nothing of the specifics of the
> original method that was called.
>
> Anyway, just my $.02. Shoot me down if out in left field. :-)
>
> Krys
>
> Jeff Watkins wrote:
>
> >
> > What about a nested validation_error function. For example:
> >
> >
> > @turbogears.expose( validators= mySchema() )
> > def index( self, arg1, arg2 )
> > def validation_failed( errors ):
> > # do something clever here and ultimately
> > # either retry index or bail
> > pass
> >
> > # real code for index
> > pass
> >
> >
> > Is it legal to have a self parameter for the nested function? If so,
> > I guess we'll have to pass it along explicitly when calling the
> > nested validation_failed function.
> >
> > Of course, if no validation_failed function is defined, the class-
> > based one should be tried next.
> >
> >
> >
> > --
> > Jeff Watkins
> > http://metrocat.org/
> >
> > "Advertising directed at children is inherently deceptive and
> > exploits children under eight years of age."
> > -- American Academy of Pediatrics
> >
> >
