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authorGuido van Rossum <guido@python.org>2007-08-25 13:43:02 (GMT)
committerGuido van Rossum <guido@python.org>2007-08-25 13:43:02 (GMT)
commit6398b7a351d04408fa8ce0204d78559e8d6ac98f (patch)
tree5f274983fa91009d1a7b4bfa26de59a83942581f /Lib/email/charset.py
parentf616b224506ef17ac9ab4378c92b99ae816b88f7 (diff)
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Remove the email package for now.
Once Barry and the email-sig have a working new version we'll add it back. If it doesn't make the 3.0a deadline (release August 31), too bad.
Diffstat (limited to 'Lib/email/charset.py')
-rw-r--r--Lib/email/charset.py391
1 files changed, 0 insertions, 391 deletions
diff --git a/Lib/email/charset.py b/Lib/email/charset.py
deleted file mode 100644
index 5b5e95d..0000000
--- a/Lib/email/charset.py
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@@ -1,391 +0,0 @@
-# Copyright (C) 2001-2006 Python Software Foundation
-# Author: Ben Gertzfield, Barry Warsaw
-# Contact: email-sig@python.org
-
-__all__ = [
- 'Charset',
- 'add_alias',
- 'add_charset',
- 'add_codec',
- ]
-
-import email.base64mime
-import email.quoprimime
-
-from email import errors
-from email.encoders import encode_7or8bit
-
-
-
-# Flags for types of header encodings
-QP = 1 # Quoted-Printable
-BASE64 = 2 # Base64
-SHORTEST = 3 # the shorter of QP and base64, but only for headers
-
-# In "=?charset?q?hello_world?=", the =?, ?q?, and ?= add up to 7
-MISC_LEN = 7
-
-DEFAULT_CHARSET = 'us-ascii'
-
-
-
-# Defaults
-CHARSETS = {
- # input header enc body enc output conv
- 'iso-8859-1': (QP, QP, None),
- 'iso-8859-2': (QP, QP, None),
- 'iso-8859-3': (QP, QP, None),
- 'iso-8859-4': (QP, QP, None),
- # iso-8859-5 is Cyrillic, and not especially used
- # iso-8859-6 is Arabic, also not particularly used
- # iso-8859-7 is Greek, QP will not make it readable
- # iso-8859-8 is Hebrew, QP will not make it readable
- 'iso-8859-9': (QP, QP, None),
- 'iso-8859-10': (QP, QP, None),
- # iso-8859-11 is Thai, QP will not make it readable
- 'iso-8859-13': (QP, QP, None),
- 'iso-8859-14': (QP, QP, None),
- 'iso-8859-15': (QP, QP, None),
- 'iso-8859-16': (QP, QP, None),
- 'windows-1252':(QP, QP, None),
- 'viscii': (QP, QP, None),
- 'us-ascii': (None, None, None),
- 'big5': (BASE64, BASE64, None),
- 'gb2312': (BASE64, BASE64, None),
- 'euc-jp': (BASE64, None, 'iso-2022-jp'),
- 'shift_jis': (BASE64, None, 'iso-2022-jp'),
- 'iso-2022-jp': (BASE64, None, None),
- 'koi8-r': (BASE64, BASE64, None),
- 'utf-8': (SHORTEST, BASE64, 'utf-8'),
- # We're making this one up to represent raw unencoded 8-bit
- '8bit': (None, BASE64, 'utf-8'),
- }
-
-# Aliases for other commonly-used names for character sets. Map
-# them to the real ones used in email.
-ALIASES = {
- 'latin_1': 'iso-8859-1',
- 'latin-1': 'iso-8859-1',
- 'latin_2': 'iso-8859-2',
- 'latin-2': 'iso-8859-2',
- 'latin_3': 'iso-8859-3',
- 'latin-3': 'iso-8859-3',
- 'latin_4': 'iso-8859-4',
- 'latin-4': 'iso-8859-4',
- 'latin_5': 'iso-8859-9',
- 'latin-5': 'iso-8859-9',
- 'latin_6': 'iso-8859-10',
- 'latin-6': 'iso-8859-10',
- 'latin_7': 'iso-8859-13',
- 'latin-7': 'iso-8859-13',
- 'latin_8': 'iso-8859-14',
- 'latin-8': 'iso-8859-14',
- 'latin_9': 'iso-8859-15',
- 'latin-9': 'iso-8859-15',
- 'latin_10':'iso-8859-16',
- 'latin-10':'iso-8859-16',
- 'cp949': 'ks_c_5601-1987',
- 'euc_jp': 'euc-jp',
- 'euc_kr': 'euc-kr',
- 'ascii': 'us-ascii',
- }
-
-
-# Map charsets to their Unicode codec strings.
-CODEC_MAP = {
- 'gb2312': 'eucgb2312_cn',
- 'big5': 'big5_tw',
- # Hack: We don't want *any* conversion for stuff marked us-ascii, as all
- # sorts of garbage might be sent to us in the guise of 7-bit us-ascii.
- # Let that stuff pass through without conversion to/from Unicode.
- 'us-ascii': None,
- }
-
-
-
-# Convenience functions for extending the above mappings
-def add_charset(charset, header_enc=None, body_enc=None, output_charset=None):
- """Add character set properties to the global registry.
-
- charset is the input character set, and must be the canonical name of a
- character set.
-
- Optional header_enc and body_enc is either Charset.QP for
- quoted-printable, Charset.BASE64 for base64 encoding, Charset.SHORTEST for
- the shortest of qp or base64 encoding, or None for no encoding. SHORTEST
- is only valid for header_enc. It describes how message headers and
- message bodies in the input charset are to be encoded. Default is no
- encoding.
-
- Optional output_charset is the character set that the output should be
- in. Conversions will proceed from input charset, to Unicode, to the
- output charset when the method Charset.convert() is called. The default
- is to output in the same character set as the input.
-
- Both input_charset and output_charset must have Unicode codec entries in
- the module's charset-to-codec mapping; use add_codec(charset, codecname)
- to add codecs the module does not know about. See the codecs module's
- documentation for more information.
- """
- if body_enc == SHORTEST:
- raise ValueError('SHORTEST not allowed for body_enc')
- CHARSETS[charset] = (header_enc, body_enc, output_charset)
-
-
-def add_alias(alias, canonical):
- """Add a character set alias.
-
- alias is the alias name, e.g. latin-1
- canonical is the character set's canonical name, e.g. iso-8859-1
- """
- ALIASES[alias] = canonical
-
-
-def add_codec(charset, codecname):
- """Add a codec that map characters in the given charset to/from Unicode.
-
- charset is the canonical name of a character set. codecname is the name
- of a Python codec, as appropriate for the second argument to the unicode()
- built-in, or to the encode() method of a Unicode string.
- """
- CODEC_MAP[charset] = codecname
-
-
-
-class Charset:
- """Map character sets to their email properties.
-
- This class provides information about the requirements imposed on email
- for a specific character set. It also provides convenience routines for
- converting between character sets, given the availability of the
- applicable codecs. Given a character set, it will do its best to provide
- information on how to use that character set in an email in an
- RFC-compliant way.
-
- Certain character sets must be encoded with quoted-printable or base64
- when used in email headers or bodies. Certain character sets must be
- converted outright, and are not allowed in email. Instances of this
- module expose the following information about a character set:
-
- input_charset: The initial character set specified. Common aliases
- are converted to their `official' email names (e.g. latin_1
- is converted to iso-8859-1). Defaults to 7-bit us-ascii.
-
- header_encoding: If the character set must be encoded before it can be
- used in an email header, this attribute will be set to
- Charset.QP (for quoted-printable), Charset.BASE64 (for
- base64 encoding), or Charset.SHORTEST for the shortest of
- QP or BASE64 encoding. Otherwise, it will be None.
-
- body_encoding: Same as header_encoding, but describes the encoding for the
- mail message's body, which indeed may be different than the
- header encoding. Charset.SHORTEST is not allowed for
- body_encoding.
-
- output_charset: Some character sets must be converted before the can be
- used in email headers or bodies. If the input_charset is
- one of them, this attribute will contain the name of the
- charset output will be converted to. Otherwise, it will
- be None.
-
- input_codec: The name of the Python codec used to convert the
- input_charset to Unicode. If no conversion codec is
- necessary, this attribute will be None.
-
- output_codec: The name of the Python codec used to convert Unicode
- to the output_charset. If no conversion codec is necessary,
- this attribute will have the same value as the input_codec.
- """
- def __init__(self, input_charset=DEFAULT_CHARSET):
- # RFC 2046, $4.1.2 says charsets are not case sensitive. We coerce to
- # unicode because its .lower() is locale insensitive. If the argument
- # is already a unicode, we leave it at that, but ensure that the
- # charset is ASCII, as the standard (RFC XXX) requires.
- try:
- if isinstance(input_charset, str):
- input_charset.encode('ascii')
- else:
- input_charset = str(input_charset, 'ascii')
- except UnicodeError:
- raise errors.CharsetError(input_charset)
- input_charset = input_charset.lower()
- # Set the input charset after filtering through the aliases
- self.input_charset = ALIASES.get(input_charset, input_charset)
- # We can try to guess which encoding and conversion to use by the
- # charset_map dictionary. Try that first, but let the user override
- # it.
- henc, benc, conv = CHARSETS.get(self.input_charset,
- (SHORTEST, BASE64, None))
- if not conv:
- conv = self.input_charset
- # Set the attributes, allowing the arguments to override the default.
- self.header_encoding = henc
- self.body_encoding = benc
- self.output_charset = ALIASES.get(conv, conv)
- # Now set the codecs. If one isn't defined for input_charset,
- # guess and try a Unicode codec with the same name as input_codec.
- self.input_codec = CODEC_MAP.get(self.input_charset,
- self.input_charset)
- self.output_codec = CODEC_MAP.get(self.output_charset,
- self.output_charset)
-
- def __str__(self):
- return self.input_charset.lower()
-
- __repr__ = __str__
-
- def __eq__(self, other):
- return str(self) == str(other).lower()
-
- def __ne__(self, other):
- return not self.__eq__(other)
-
- def get_body_encoding(self):
- """Return the content-transfer-encoding used for body encoding.
-
- This is either the string `quoted-printable' or `base64' depending on
- the encoding used, or it is a function in which case you should call
- the function with a single argument, the Message object being
- encoded. The function should then set the Content-Transfer-Encoding
- header itself to whatever is appropriate.
-
- Returns "quoted-printable" if self.body_encoding is QP.
- Returns "base64" if self.body_encoding is BASE64.
- Returns "7bit" otherwise.
- """
- assert self.body_encoding != SHORTEST
- if self.body_encoding == QP:
- return 'quoted-printable'
- elif self.body_encoding == BASE64:
- return 'base64'
- else:
- return encode_7or8bit
-
- def convert(self, s):
- """Convert a string from the input_codec to the output_codec."""
- if self.input_codec != self.output_codec:
- return str(s, self.input_codec).encode(self.output_codec)
- else:
- return s
-
- def to_splittable(self, s):
- """Convert a possibly multibyte string to a safely splittable format.
-
- Uses the input_codec to try and convert the string to Unicode, so it
- can be safely split on character boundaries (even for multibyte
- characters).
-
- Returns the string as-is if it isn't known how to convert it to
- Unicode with the input_charset.
-
- Characters that could not be converted to Unicode will be replaced
- with the Unicode replacement character U+FFFD.
- """
- if isinstance(s, str) or self.input_codec is None:
- return s
- try:
- return str(s, self.input_codec, 'replace')
- except LookupError:
- # Input codec not installed on system, so return the original
- # string unchanged.
- return s
-
- def from_splittable(self, ustr, to_output=True):
- """Convert a splittable string back into an encoded string.
-
- Uses the proper codec to try and convert the string from Unicode back
- into an encoded format. Return the string as-is if it is not Unicode,
- or if it could not be converted from Unicode.
-
- Characters that could not be converted from Unicode will be replaced
- with an appropriate character (usually '?').
-
- If to_output is True (the default), uses output_codec to convert to an
- encoded format. If to_output is False, uses input_codec.
- """
- if to_output:
- codec = self.output_codec
- else:
- codec = self.input_codec
- if not isinstance(ustr, str) or codec is None:
- return ustr
- try:
- return ustr.encode(codec, 'replace')
- except LookupError:
- # Output codec not installed
- return ustr
-
- def get_output_charset(self):
- """Return the output character set.
-
- This is self.output_charset if that is not None, otherwise it is
- self.input_charset.
- """
- return self.output_charset or self.input_charset
-
- def encoded_header_len(self, s):
- """Return the length of the encoded header string."""
- cset = self.get_output_charset()
- # The len(s) of a 7bit encoding is len(s)
- if self.header_encoding == BASE64:
- return email.base64mime.base64_len(s) + len(cset) + MISC_LEN
- elif self.header_encoding == QP:
- return email.quoprimime.header_quopri_len(s) + len(cset) + MISC_LEN
- elif self.header_encoding == SHORTEST:
- lenb64 = email.base64mime.base64_len(s)
- lenqp = email.quoprimime.header_quopri_len(s)
- return min(lenb64, lenqp) + len(cset) + MISC_LEN
- else:
- return len(s)
-
- def header_encode(self, s, convert=False):
- """Header-encode a string, optionally converting it to output_charset.
-
- If convert is True, the string will be converted from the input
- charset to the output charset automatically. This is not useful for
- multibyte character sets, which have line length issues (multibyte
- characters must be split on a character, not a byte boundary); use the
- high-level Header class to deal with these issues. convert defaults
- to False.
-
- The type of encoding (base64 or quoted-printable) will be based on
- self.header_encoding.
- """
- cset = self.get_output_charset()
- if convert:
- s = self.convert(s)
- # 7bit/8bit encodings return the string unchanged (modulo conversions)
- if self.header_encoding == BASE64:
- return email.base64mime.header_encode(s, cset)
- elif self.header_encoding == QP:
- return email.quoprimime.header_encode(s, cset, maxlinelen=None)
- elif self.header_encoding == SHORTEST:
- lenb64 = email.base64mime.base64_len(s)
- lenqp = email.quoprimime.header_quopri_len(s)
- if lenb64 < lenqp:
- return email.base64mime.header_encode(s, cset)
- else:
- return email.quoprimime.header_encode(s, cset, maxlinelen=None)
- else:
- return s
-
- def body_encode(self, s, convert=True):
- """Body-encode a string and convert it to output_charset.
-
- If convert is True (the default), the string will be converted from
- the input charset to output charset automatically. Unlike
- header_encode(), there are no issues with byte boundaries and
- multibyte charsets in email bodies, so this is usually pretty safe.
-
- The type of encoding (base64 or quoted-printable) will be based on
- self.body_encoding.
- """
- if convert:
- s = self.convert(s)
- # 7bit/8bit encodings return the string unchanged (module conversions)
- if self.body_encoding is BASE64:
- return email.base64mime.body_encode(s)
- elif self.body_encoding is QP:
- return email.quoprimime.body_encode(s)
- else:
- return s