[Web-SIG] WSGI 2.0

Manlio Perillo manlio_perillo at libero.it
Thu Oct 4 18:58:50 CEST 2007

Phillip J. Eby ha scritto:
> At 06:37 PM 10/4/2007 +0200, Manlio Perillo wrote:
>> To make an example (not tested), suppose that a WSGI application keeps a
>> global counter (as a thread specific data).
>> When a new request arrives, the counter is reset to 0, and its value is
>> incremented for every iteration.
>> With all the existing WSGI implementation (as far as I know), we always
>> know the current value of the counter: it will start at 0, reach the
>> number of iterations, and then will start at 0 again.
> So?  An application that does this is obviously broken.  Again, remember 
> that the WSGI spec encourages interleaving, so any multi-threaded server 
> is well within its  rights to do the same thing.
> There is nothing in WSGI that says multiple simultaneous requests cannot 
> be run in the same thread.  Therefore, nothing is guaranteed about what 
> happens to global or thread-local resources while the application (or 
> its returned iterable) is not actually executing.

But why you are against adding a new environ value (not necessary named 
wsgi.asynchronous), that will explicitly state if the WSGI server will 
interleave the WSGI application?

Regards  Manlio Perillo

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