[Zope-dev] __after_publishing_traverse__

[Ivo van der Wijk]

On Mon, Apr 15, 2002 at 09:39:47AM -0600, Casey Duncan wrote:
> The request object has a hold area which keeps objects alive as long as 
> the request lives. Although I have not tried it, you might be able to 
> add an object to this hold area using __bobo_traverse__ defined on B.
> 
> This object's class would need to have a destructor method (__del__) 
> defined so that it can do something when the request is over and the 
> response has presumably been written.
> 
> you could code that something like this:
> 
> In b's class:
> 
> class b:
>      ...
>      def __bobo_traverse__(self, name):
>          self.REQUEST._hold(ResponseChecker(self.REQUEST.RESPONSE))
> 
> class ResponseChecker:
>      def __init__(self, response):
>          self.response = response
> 
>      def __del__(self):
>          ...do something with self.response...
> 
> Like I said, I've never tried this, but you never know, it might work. 
> If not, another option would be to have b use __bobo_traverse__ to 
> dynamically add a destructor to the RESPONSE object (it doesn't already 
> have one AFAIK). Like this:
> 

This indeed does work. The only difference is that I'm installing the hook
in __before_publishing_traverse__, so I don't have to do any traversal
myself.

I find it a scary solution though (though not as scary as monkeypatching
__del__), so I'm not 100% sure if I will use this code, or perhaps I'll
make it very optional (basically, thanks to this nice hack, QuotaFolder can 
do traffic accounting as well :)

Cheers,

	Ivo

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