On Sun, Sep 20, 2009 at 11:25 PM, Chris McDonough <chr...@plope.com> wrote: > WSGI is a fairly low-level protocol aimed at folks who need to interface a > server to the outside world. The outside world (by its nature) talks bytes. > I fear that any implied conversion of environment values and iterable > return values to Unicode will actually eventually make things harder than > they are now. I realize that it would make middleware implementors lives > harder to need to deal in bytes. However, at this point, I also believe > that middleware kinda should be hard. We have way too much middleware that > shouldn't be middleware these days (some written by myself).
Well, ordinarily I'd be inclined to agree: HTTP deals in bytes, so an interface to HTTP should deal in bytes as well. The problem, really is that despite being a very low-level interface, WSGI has a tendency to leak up into much higher-level code, and (IMO) authors of that high-level code really shouldn't have to waste their time dealing with details of the underlying low-level gateway. You've said you don't want to hear "Python 3" as the reason, but it provides some useful examples: in high-level code you'll commonly want to be doing things like, say, comparing parts of the requested URL path to known strings or patterns. And that high-level code will almost certainly use strings, while WSGI, in theory, will be using bytes. That's just a recipe for disaster; if WSGI mandates bytes, then bytes will have to start "infecting" much higher-level code (since Python 3 -- rightly -- doesn't let you be nearly as promiscuous about mixing bytes and strings). Once I'm at a point where I can use Python 3, I know I'll personally be looking for some library which will normalize everything for me before I interact with it, precisely to avoid this sort of leakage; if WSGI itself would at least *allow* that normalization to happen at the low level (mandating it is another discussion entirely) I'd feel much happier about it going forward. -- "Bureaucrat Conrad, you are technically correct -- the best kind of correct." _______________________________________________ Web-SIG mailing list Web-SIG@python.org Web SIG: http://www.python.org/sigs/web-sig Unsubscribe: http://mail.python.org/mailman/options/web-sig/archive%40mail-archive.com
