django.util.encoding.py
import types
import urllib
import locale
import datetime
import codecs
from decimal import Decimal
from django.utils.functional import Promise
class DjangoUnicodeDecodeError(UnicodeDecodeError):
def __init__(self, obj, *args):
self.obj = obj
UnicodeDecodeError.__init__(self, *args)
def __str__(self):
original = UnicodeDecodeError.__str__(self)
return '%s. You passed in %r (%s)' % (original, self.obj,
type(self.obj))
class StrAndUnicode(object):
"""
A class whose __str__ returns its __unicode__ as a UTF-8 bytestring.
Useful as a mix-in.
"""
def __str__(self):
return self.__unicode__().encode('utf-8')
def smart_unicode(s, encoding='utf-8', strings_only=False, errors='strict'):
"""
Returns a unicode object representing 's'. Treats bytestrings using the
'encoding' codec.
If strings_only is True, don't convert (some) non-string-like objects.
"""
if isinstance(s, Promise):
# The input is the result of a gettext_lazy() call.
return s
return force_unicode(s, encoding, strings_only, errors)
def is_protected_type(obj):
"""Determine if the object instance is of a protected type.
Objects of protected types are preserved as-is when passed to
force_unicode(strings_only=True).
"""
return isinstance(obj, (
types.NoneType,
int, long,
datetime.datetime, datetime.date, datetime.time,
float, Decimal)
)
def force_unicode(s, encoding='utf-8', strings_only=False, errors='strict'):
"""
Similar to smart_unicode, except that lazy instances are resolved to
strings, rather than kept as lazy objects.
If strings_only is True, don't convert (some) non-string-like objects.
"""
# Handle the common case first, saves 30-40% in performance when s
# is an instance of unicode. This function gets called often in that
# setting.
if isinstance(s, unicode):
return s
if strings_only and is_protected_type(s):
return s
try:
if not isinstance(s, basestring,):
if hasattr(s, '__unicode__'):
s = unicode(s)
else:
try:
s = unicode(str(s), encoding, errors)
except UnicodeEncodeError:
if not isinstance(s, Exception):
raise
# If we get to here, the caller has passed in an Exception
# subclass populated with non-ASCII data without special
# handling to display as a string. We need to handle this
# without raising a further exception. We do an
# approximation to what the Exception's standard str()
# output should be.
s = ' '.join([force_unicode(arg, encoding, strings_only,
errors) for arg in s])
elif not isinstance(s, unicode):
# Note: We use .decode() here, instead of unicode(s, encoding,
# errors), so that if s is a SafeString, it ends up being a
# SafeUnicode at the end.
s = s.decode(encoding, errors)
except UnicodeDecodeError, e:
if not isinstance(s, Exception):
raise DjangoUnicodeDecodeError(s, *e.args)
else:
# If we get to here, the caller has passed in an Exception
# subclass populated with non-ASCII bytestring data without a
# working unicode method. Try to handle this without raising a
# further exception by individually forcing the exception args
# to unicode.
s = ' '.join([force_unicode(arg, encoding, strings_only,
errors) for arg in s])
return s
def smart_str(s, encoding='utf-8', strings_only=False, errors='strict'):
"""
Returns a bytestring version of 's', encoded as specified in 'encoding'.
If strings_only is True, don't convert (some) non-string-like objects.
"""
if strings_only and isinstance(s, (types.NoneType, int)):
return s
if isinstance(s, Promise):
return unicode(s).encode(encoding, errors)
elif not isinstance(s, basestring):
try:
return str(s)
except UnicodeEncodeError:
if isinstance(s, Exception):
# An Exception subclass containing non-ASCII data that doesn't
# know how to print itself properly. We shouldn't raise a
# further exception.
return ' '.join([smart_str(arg, encoding, strings_only,
errors) for arg in s])
return unicode(s).encode(encoding, errors)
elif isinstance(s, unicode):
return s.encode(encoding, errors)
elif s and encoding != 'utf-8':
return s.decode('utf-8', errors).encode(encoding, errors)
else:
return s
def iri_to_uri(iri):
"""
Convert an Internationalized Resource Identifier (IRI) portion to a URI
portion that is suitable for inclusion in a URL.
This is the algorithm from section 3.1 of RFC 3987. However, since we are
assuming input is either UTF-8 or unicode already, we can simplify things a
little from the full method.
Returns an ASCII string containing the encoded result.
"""
# The list of safe characters here is constructed from the "reserved" and
# "unreserved" characters specified in sections 2.2 and 2.3 of RFC 3986:
# reserved = gen-delims / sub-delims
# gen-delims = ":" / "/" / "?" / "#" / "[" / "]" / "@"
# sub-delims = "!" / "$" / "&" / "'" / "(" / ")"
# / "*" / "+" / "," / ";" / "="
# unreserved = ALPHA / DIGIT / "-" / "." / "_" / "~"
# Of the unreserved characters, urllib.quote already considers all but
# the ~ safe.
# The % character is also added to the list of safe characters here, as the
# end of section 3.1 of RFC 3987 specifically mentions that % must not be
# converted.
if iri is None:
return iri
return urllib.quote(smart_str(iri), safe="/#%[]=:;$&()+,!?*@'~")
def filepath_to_uri(path):
"""Convert an file system path to a URI portion that is suitable for
inclusion in a URL.
We are assuming input is either UTF-8 or unicode already.
This method will encode certain chars that would normally be recognized as
special chars for URIs. Note that this method does not encode the '
character, as it is a valid character within URIs. See
encodeURIComponent() JavaScript function for more details.
Returns an ASCII string containing the encoded result.
"""
if path is None:
return path
# I know about `os.sep` and `os.altsep` but I want to leave
# some flexibility for hardcoding separators.
return urllib.quote(smart_str(path).replace("\\", "/"), safe="/~!*()'")
# The encoding of the default system locale but falls back to the
# given fallback encoding if the encoding is unsupported by python or could
# not be determined. See tickets #10335 and #5846
try:
DEFAULT_LOCALE_ENCODING = locale.getdefaultlocale()[1] or 'ascii'
codecs.lookup(DEFAULT_LOCALE_ENCODING)
except:
DEFAULT_LOCALE_ENCODING = 'ascii'