[Python-Dev] PEP 3333: wsgi_string() function

[Victor Stinner]

Hi,

In the PEP 3333, I read:
--------------
import os, sys

enc, esc = sys.getfilesystemencoding(), 'surrogateescape'

def wsgi_string(u):
    # Convert an environment variable to a WSGI "bytes-as-unicode"
string
    return u.encode(enc, esc).decode('iso-8859-1')

def run_with_cgi(application):
    environ = {k: wsgi_string(v) for k,v in os.environ.items()}
    environ['wsgi.input']        = sys.stdin
    environ['wsgi.errors']       = sys.stderr
    environ['wsgi.version']      = (1, 0)
...
--------------

What is this horrible encoding "bytes-as-unicode"? os.environ is
supposed to be correctly decoded and contain valid unicode characters.
If WSGI uses another encoding than the locale encoding (which is a bad
idea), it should use os.environb and decodes keys and values using its
own encoding.

If you really want to store bytes in unicode, str is not the right type:
use the bytes type and use os.environb instead.

Victor