[Web-SIG] Proposal: Handling POST forms in WSGI

[Ian Bicking]

Hans Then wrote:
> Phillip,
> 
>> -1 on this being middleware.  If middleware wants to read the input,
>> it should copy it to a temporary file or StringIO, not remove it.
> 
>> The simple, standard way to do something like this would be to have a
>> library routine like 'get_form_vars(environ)'.  The routine would
>> check for the form vars key, and if not present, then it would
>> process the input and cache the information in the environment.  It
>> could even have an option to clone the input, in case the routine is
>> being used from middleware.
> 
> I think Ian's point is to standardise on a form key and on the interface of
> the form object. Your point is valid that middleware should not
> destructively read the wsgi.input variable.
> 
> Many web applications will at some point call other web applications. It
> seems positively wasteful to have to clone and parse wsgi.input over and
> over again. It makes sense to do it once, in middleware, and then stuff it
> in a standard place in the wsgi environ.

Ideally I'm not expecting middleware to do this parsing (unless there's 
some good reason for the middleware to want the information).  I'm 
suggesting a way the parsing can be done in a lazy fashion, but that one 
consumer doesn't get exclusive access to it.

I also see this as a kind of prerequisite for supporting multiple 
request objects over the WSGI environment, as each object is going to 
want access to wsgi.input.


-- 
Ian Bicking | ianb at colorstudy.com | http://blog.ianbicking.org