• Language: en

Source code for django.utils.encoding

import codecs
import datetime
import locale
from decimal import Decimal
from urllib.parse import quote

from django.utils import six
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))


# For backwards compatibility. (originally in Django, then added to six 1.9)
python_2_unicode_compatible = six.python_2_unicode_compatible


[docs]def smart_text(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_text(s, encoding, strings_only, errors)
_PROTECTED_TYPES = ( type(None), int, float, Decimal, datetime.datetime, datetime.date, datetime.time, )
[docs]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_text(strings_only=True). """ return isinstance(obj, _PROTECTED_TYPES)
[docs]def force_text(s, encoding='utf-8', strings_only=False, errors='strict'): """ Similar to smart_text, 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
[docs]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)
[docs]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) if isinstance(s, Promise) or not isinstance(s, str): return str(s).encode(encoding, errors) else: return s.encode(encoding, errors)
smart_str = smart_text force_str = force_text smart_str.__doc__ = """ Apply smart_text in Python 3 and smart_bytes in Python 2. This is suitable for writing to sys.stdout (for instance). """ force_str.__doc__ = """ Apply force_text in Python 3 and force_bytes in Python 2. """
[docs]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 })
[docs]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()
[docs]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 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. """ try: path.decode() except UnicodeDecodeError as e: repercent = quote(path[e.start:e.end], safe=b"/#%[]=:;$&()+,!?*@'~") path = repercent_broken_unicode( path[:e.start] + force_bytes(repercent) + path[e.end:]) return path
[docs]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(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()
Back to Top