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author | Guido van Rossum <guido@python.org> | 2007-08-25 13:43:02 (GMT) |
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committer | Guido van Rossum <guido@python.org> | 2007-08-25 13:43:02 (GMT) |
commit | 6398b7a351d04408fa8ce0204d78559e8d6ac98f (patch) | |
tree | 5f274983fa91009d1a7b4bfa26de59a83942581f /Lib/email/charset.py | |
parent | f616b224506ef17ac9ab4378c92b99ae816b88f7 (diff) | |
download | cpython-6398b7a351d04408fa8ce0204d78559e8d6ac98f.zip cpython-6398b7a351d04408fa8ce0204d78559e8d6ac98f.tar.gz cpython-6398b7a351d04408fa8ce0204d78559e8d6ac98f.tar.bz2 |
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.py | 391 |
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 +++ /dev/null @@ -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 |