[Zope] catching BadRequest exceptions

[Palermo, Tom]

I'm trying to catch when someone tries to create an object with the same Id
as another object. I thought this was handled by checkValidId. It doesn't
appear that this error is handled by standard_error_message. Whenever this
error happens, the rror message is not skinned like the site I'm working on
(ie. It's just some very basic html output). 

Thanks,
Tom

-----Original Message-----
From: Dieter Maurer [mailto:dieter at handshake.de] 
Sent: Saturday, March 04, 2006 2:29 PM
To: Palermo, Tom
Cc: 'zope at zope.org'
Subject: Re: [Zope] catching BadRequest exceptions

Palermo, Tom wrote at 2006-3-3 13:56 -0500:
> ...
>It seems that BadRequest exceptions, like the ones thrown by 
>checkValidId() in OFS.ObjectManager (lib/python/OFS/ObjectManager.py), 
>are not handled by a standard_error_message.

Some "BadRequest" exceptions are not handled by "standard_error_message"
(a bug, please file a bug report). But, this is not the case for the one
from "checkValidId".

Affected are errors detected in "REQUEST.processInputs()".
They are not handled by "standard_error_message" because they are detected
too early -- before traversal has even begun.
As a result, there is not yet any "standard_error_message" in the request
context.

These errors are usually type errors during conversion of request parameters
called for by ":<type>" suffixes, e.g.
"start:int=a" would cause such an error.

The easy workaround is not to use such ZPublisher type conversions but
perform the conversions yourself in your application code.

--
Dieter