[Web-SIG] some questions about start_response implementation

[Manlio Perillo]

Phillip J. Eby ha scritto:
> At 06:21 PM 10/15/2007 +0200, Manlio Perillo wrote:
>> Phillip J. Eby ha scritto:
>> > At 05:52 PM 10/15/2007 +0200, Manlio Perillo wrote:
>> >> Hi.
>> >>
>> >> I'm implementing the start_response callable for Nginx mod_wsgi and I
>> >> have a few questions.
>> >>
>> >> 1) From the WSGI PEP it seems that an implementation is allowed to
>> >>     *always* raise an exception when start_response is called with 
>> a not
>> >>     null exc_info.
>> >>
>> >>     Is this true?
>> >
>> > Yes - as long as it's the exc_info passed in, i.e.:
>>
>> It seems that WSGI *does not* requires the application to raise the
>> exc_info passed.
> 
> We're talking about the *server*, not the application:
> 

Sorry, I have written application, but I meant server :-).

> "if exc_info is provided, and the HTTP headers have already been sent, 
> start_response MUST raise an error, and SHOULD raise the exc_info tuple."
> 
> So, it's a "should" for the server, with the intent being that you 
> should have some special reason for not doing so.  This is later 
> clarified in the PEP as meaning that exception-handling middleware may 
> have reasons to raise an alternative error or not raise an error.  
> However, there aren't any anticipated use cases for server gateways to 
> do anything but raise the passed-in errors.
> 

Ok, thanks for the clarification.

 > [...]


Regards  Manlio Perillo