django1/django/utils/encoding.py

274 lines
9.1 KiB
Python

import codecs
import datetime
import locale
import warnings
from decimal import Decimal
from urllib.parse import quote
from django.utils.deprecation import RemovedInDjango40Warning
from django.utils.functional import Promise
class DjangoUnicodeDecodeError(UnicodeDecodeError):
def __init__(self, obj, *args):
self.obj = obj
super().__init__(*args)
def __str__(self):
return '%s. You passed in %r (%s)' % (super().__str__(), self.obj, type(self.obj))
def smart_str(s, encoding='utf-8', strings_only=False, errors='strict'):
"""
Return a string representing 's'. Treat 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_str(s, encoding, strings_only, errors)
_PROTECTED_TYPES = (
type(None), int, float, Decimal, datetime.datetime, datetime.date, datetime.time,
)
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_str(strings_only=True).
"""
return isinstance(obj, _PROTECTED_TYPES)
def force_str(s, encoding='utf-8', strings_only=False, errors='strict'):
"""
Similar to smart_str(), 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 for performance reasons.
if issubclass(type(s), str):
return s
if strings_only and is_protected_type(s):
return s
try:
if isinstance(s, bytes):
s = str(s, encoding, errors)
else:
s = str(s)
except UnicodeDecodeError as e:
raise DjangoUnicodeDecodeError(s, *e.args)
return s
def smart_bytes(s, encoding='utf-8', strings_only=False, errors='strict'):
"""
Return a bytestring version of 's', encoded as specified in 'encoding'.
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_bytes(s, encoding, strings_only, errors)
def force_bytes(s, encoding='utf-8', strings_only=False, errors='strict'):
"""
Similar to smart_bytes, 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 for performance reasons.
if isinstance(s, bytes):
if encoding == 'utf-8':
return s
else:
return s.decode('utf-8', errors).encode(encoding, errors)
if strings_only and is_protected_type(s):
return s
if isinstance(s, memoryview):
return bytes(s)
return str(s).encode(encoding, errors)
def smart_text(s, encoding='utf-8', strings_only=False, errors='strict'):
warnings.warn(
'smart_text() is deprecated in favor of smart_str().',
RemovedInDjango40Warning, stacklevel=2,
)
return smart_str(s, encoding, strings_only, errors)
def force_text(s, encoding='utf-8', strings_only=False, errors='strict'):
warnings.warn(
'force_text() is deprecated in favor of force_str().',
RemovedInDjango40Warning, stacklevel=2,
)
return force_str(s, encoding, strings_only, errors)
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, slightly simplified
since the input is assumed to be a string rather than an arbitrary byte
stream.
Take an IRI (string or UTF-8 bytes, e.g. '/I ♥ Django/' or
b'/I \xe2\x99\xa5 Django/') and return a string containing the encoded
result with ASCII chars only (e.g. '/I%20%E2%99%A5%20Django/').
"""
# 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 = "!" / "$" / "&" / "'" / "(" / ")"
# / "*" / "+" / "," / ";" / "="
# unreserved = ALPHA / DIGIT / "-" / "." / "_" / "~"
# Of the unreserved characters, urllib.parse.quote() already considers all
# but the ~ safe.
# The % character is also added to the list of safe characters here, as the
# end of section 3.1 of RFC 3987 specifically mentions that % must not be
# converted.
if iri is None:
return iri
elif isinstance(iri, Promise):
iri = str(iri)
return quote(iri, safe="/#%[]=:;$&()+,!?*@'~")
# List of byte values that uri_to_iri() decodes from percent encoding.
# First, the unreserved characters from RFC 3986:
_ascii_ranges = [[45, 46, 95, 126], range(65, 91), range(97, 123)]
_hextobyte = {
(fmt % char).encode(): bytes((char,))
for ascii_range in _ascii_ranges
for char in ascii_range
for fmt in ['%02x', '%02X']
}
# And then everything above 128, because bytes ≥ 128 are part of multibyte
# Unicode characters.
_hexdig = '0123456789ABCDEFabcdef'
_hextobyte.update({
(a + b).encode(): bytes.fromhex(a + b)
for a in _hexdig[8:] for b in _hexdig
})
def uri_to_iri(uri):
"""
Convert a Uniform Resource Identifier(URI) into an Internationalized
Resource Identifier(IRI).
This is the algorithm from section 3.2 of RFC 3987, excluding step 4.
Take an URI in ASCII bytes (e.g. '/I%20%E2%99%A5%20Django/') and return
a string containing the encoded result (e.g. '/I%20♥%20Django/').
"""
if uri is None:
return uri
uri = force_bytes(uri)
# Fast selective unqote: First, split on '%' and then starting with the
# second block, decode the first 2 bytes if they represent a hex code to
# decode. The rest of the block is the part after '%AB', not containing
# any '%'. Add that to the output without further processing.
bits = uri.split(b'%')
if len(bits) == 1:
iri = uri
else:
parts = [bits[0]]
append = parts.append
hextobyte = _hextobyte
for item in bits[1:]:
hex = item[:2]
if hex in hextobyte:
append(hextobyte[item[:2]])
append(item[2:])
else:
append(b'%')
append(item)
iri = b''.join(parts)
return repercent_broken_unicode(iri).decode()
def escape_uri_path(path):
"""
Escape the unsafe characters from the path portion of a Uniform Resource
Identifier (URI).
"""
# These are the "reserved" and "unreserved" characters specified in
# sections 2.2 and 2.3 of RFC 2396:
# reserved = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" | "$" | ","
# unreserved = alphanum | mark
# mark = "-" | "_" | "." | "!" | "~" | "*" | "'" | "(" | ")"
# The list of safe characters here is constructed subtracting ";", "=",
# and "?" according to section 3.3 of RFC 2396.
# The reason for not subtracting and escaping "/" is that we are escaping
# the entire path, not a path segment.
return quote(path, safe="/:@&+$,-_.!~*'()")
def punycode(domain):
"""Return the Punycode of the given domain if it's non-ASCII."""
return domain.encode('idna').decode('ascii')
def repercent_broken_unicode(path):
"""
As per section 3.2 of RFC 3987, step three of converting a URI into an IRI,
repercent-encode any octet produced that is not part of a strictly legal
UTF-8 octet sequence.
"""
while True:
try:
path.decode()
except UnicodeDecodeError as e:
# CVE-2019-14235: A recursion shouldn't be used since the exception
# handling uses massive amounts of memory
repercent = quote(path[e.start:e.end], safe=b"/#%[]=:;$&()+,!?*@'~")
path = path[:e.start] + repercent.encode() + path[e.end:]
else:
return path
def filepath_to_uri(path):
"""Convert a file system path to a URI portion that is suitable for
inclusion in a URL.
Encode certain chars that would normally be recognized as special chars
for URIs. Do not encode the ' character, as it is a valid character
within URIs. See the encodeURIComponent() JavaScript function for details.
"""
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 quote(str(path).replace("\\", "/"), safe="/~!*()'")
def get_system_encoding():
"""
The encoding of the default system locale. Fallback to 'ascii' if the
#encoding is unsupported by Python or could not be determined. See tickets
#10335 and #5846.
"""
try:
encoding = locale.getdefaultlocale()[1] or 'ascii'
codecs.lookup(encoding)
except Exception:
encoding = 'ascii'
return encoding
DEFAULT_LOCALE_ENCODING = get_system_encoding()