[Web-SIG] WSGI 2

[P.J. Eby]

At 10:44 PM 8/4/2009 +1000, Graham Dumpleton wrote:
>In summary, what are the practical uses cases that would make passing
>bytes over UTF-8 or even latin-1 worthwhile?

My concern at this point is a nagging feeling that we are abandoning 
WSGI<->HTTP equivalence for convenience in the face of changes in 
Python's defaults.  Had Python 3 been the standard version in 
existence when WSGI 1 was created, I would've argued for making 
*everything* bytes, in order to:

1. Force all encodings to be explicit, and
2. Ensure WSGI<->HTTP equivalence (i.e., WSGI==HTTP encoded in Python objects)

And this is why the original spec said that Unicode strings should be 
treated as bytes -- because byte strings were always the original 
target of the spec.

Please remember that WSGI is not primarily intended to provide 
application developers with a convenient API; its first and most 
important job is to ship the data around without mangling it in the process.

HTTP moves bytes, therefore WSGI should move bytes.  For practical 
reasons, it would be good to *also* support strings on the 
application side, especially for application migration.  However, I 
see no reason to make *servers* provide decoded strings instead of bytes.

So I would ask, what is the practical use case for having the server 
decode bytes into strings, instead of leaving them as bytes?