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+# Copyright (C) 2001-2007 Python Software Foundation
+# Author: Barry Warsaw
+# Contact: email-sig@python.org
+
+"""Miscellaneous utilities."""
+
+__all__ = [
+ 'collapse_rfc2231_value',
+ 'decode_params',
+ 'decode_rfc2231',
+ 'encode_rfc2231',
+ 'formataddr',
+ 'formatdate',
+ 'getaddresses',
+ 'make_msgid',
+ 'parseaddr',
+ 'parsedate',
+ 'parsedate_tz',
+ 'unquote',
+ ]
+
+import os
+import re
+import time
+import base64
+import random
+import socket
+import urllib
+import warnings
+from io import StringIO
+
+from email._parseaddr import quote
+from email._parseaddr import AddressList as _AddressList
+from email._parseaddr import mktime_tz
+
+# We need wormarounds for bugs in these methods in older Pythons (see below)
+from email._parseaddr import parsedate as _parsedate
+from email._parseaddr import parsedate_tz as _parsedate_tz
+
+from quopri import decodestring as _qdecode
+
+# Intrapackage imports
+from email.encoders import _bencode, _qencode
+
+COMMASPACE = ', '
+EMPTYSTRING = ''
+UEMPTYSTRING = ''
+CRLF = '\r\n'
+TICK = "'"
+
+specialsre = re.compile(r'[][\\()<>@,:;".]')
+escapesre = re.compile(r'[][\\()"]')
+
+
+
+# Helpers
+
+def _identity(s):
+ return s
+
+
+def _bdecode(s):
+ # We can't quite use base64.encodestring() since it tacks on a "courtesy
+ # newline". Blech!
+ if not s:
+ return s
+ value = base64.decodestring(s)
+ if not s.endswith('\n') and value.endswith('\n'):
+ return value[:-1]
+ return value
+
+
+
+def fix_eols(s):
+ """Replace all line-ending characters with \r\n."""
+ # Fix newlines with no preceding carriage return
+ s = re.sub(r'(?<!\r)\n', CRLF, s)
+ # Fix carriage returns with no following newline
+ s = re.sub(r'\r(?!\n)', CRLF, s)
+ return s
+
+
+
+def formataddr(pair):
+ """The inverse of parseaddr(), this takes a 2-tuple of the form
+ (realname, email_address) and returns the string value suitable
+ for an RFC 2822 From, To or Cc header.
+
+ If the first element of pair is false, then the second element is
+ returned unmodified.
+ """
+ name, address = pair
+ if name:
+ quotes = ''
+ if specialsre.search(name):
+ quotes = '"'
+ name = escapesre.sub(r'\\\g<0>', name)
+ return '%s%s%s <%s>' % (quotes, name, quotes, address)
+ return address
+
+
+
+def getaddresses(fieldvalues):
+ """Return a list of (REALNAME, EMAIL) for each fieldvalue."""
+ all = COMMASPACE.join(fieldvalues)
+ a = _AddressList(all)
+ return a.addresslist
+
+
+
+ecre = re.compile(r'''
+ =\? # literal =?
+ (?P<charset>[^?]*?) # non-greedy up to the next ? is the charset
+ \? # literal ?
+ (?P<encoding>[qb]) # either a "q" or a "b", case insensitive
+ \? # literal ?
+ (?P<atom>.*?) # non-greedy up to the next ?= is the atom
+ \?= # literal ?=
+ ''', re.VERBOSE | re.IGNORECASE)
+
+
+
+def formatdate(timeval=None, localtime=False, usegmt=False):
+ """Returns a date string as specified by RFC 2822, e.g.:
+
+ Fri, 09 Nov 2001 01:08:47 -0000
+
+ Optional timeval if given is a floating point time value as accepted by
+ gmtime() and localtime(), otherwise the current time is used.
+
+ Optional localtime is a flag that when True, interprets timeval, and
+ returns a date relative to the local timezone instead of UTC, properly
+ taking daylight savings time into account.
+
+ Optional argument usegmt means that the timezone is written out as
+ an ascii string, not numeric one (so "GMT" instead of "+0000"). This
+ is needed for HTTP, and is only used when localtime==False.
+ """
+ # Note: we cannot use strftime() because that honors the locale and RFC
+ # 2822 requires that day and month names be the English abbreviations.
+ if timeval is None:
+ timeval = time.time()
+ if localtime:
+ now = time.localtime(timeval)
+ # Calculate timezone offset, based on whether the local zone has
+ # daylight savings time, and whether DST is in effect.
+ if time.daylight and now[-1]:
+ offset = time.altzone
+ else:
+ offset = time.timezone
+ hours, minutes = divmod(abs(offset), 3600)
+ # Remember offset is in seconds west of UTC, but the timezone is in
+ # minutes east of UTC, so the signs differ.
+ if offset > 0:
+ sign = '-'
+ else:
+ sign = '+'
+ zone = '%s%02d%02d' % (sign, hours, minutes // 60)
+ else:
+ now = time.gmtime(timeval)
+ # Timezone offset is always -0000
+ if usegmt:
+ zone = 'GMT'
+ else:
+ zone = '-0000'
+ return '%s, %02d %s %04d %02d:%02d:%02d %s' % (
+ ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun'][now[6]],
+ now[2],
+ ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
+ 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'][now[1] - 1],
+ now[0], now[3], now[4], now[5],
+ zone)
+
+
+
+def make_msgid(idstring=None):
+ """Returns a string suitable for RFC 2822 compliant Message-ID, e.g:
+
+ <20020201195627.33539.96671@nightshade.la.mastaler.com>
+
+ Optional idstring if given is a string used to strengthen the
+ uniqueness of the message id.
+ """
+ timeval = time.time()
+ utcdate = time.strftime('%Y%m%d%H%M%S', time.gmtime(timeval))
+ pid = os.getpid()
+ randint = random.randrange(100000)
+ if idstring is None:
+ idstring = ''
+ else:
+ idstring = '.' + idstring
+ idhost = socket.getfqdn()
+ msgid = '<%s.%s.%s%s@%s>' % (utcdate, pid, randint, idstring, idhost)
+ return msgid
+
+
+
+# These functions are in the standalone mimelib version only because they've
+# subsequently been fixed in the latest Python versions. We use this to worm
+# around broken older Pythons.
+def parsedate(data):
+ if not data:
+ return None
+ return _parsedate(data)
+
+
+def parsedate_tz(data):
+ if not data:
+ return None
+ return _parsedate_tz(data)
+
+
+def parseaddr(addr):
+ addrs = _AddressList(addr).addresslist
+ if not addrs:
+ return '', ''
+ return addrs[0]
+
+
+# rfc822.unquote() doesn't properly de-backslash-ify in Python pre-2.3.
+def unquote(str):
+ """Remove quotes from a string."""
+ if len(str) > 1:
+ if str.startswith('"') and str.endswith('"'):
+ return str[1:-1].replace('\\\\', '\\').replace('\\"', '"')
+ if str.startswith('<') and str.endswith('>'):
+ return str[1:-1]
+ return str
+
+
+
+# RFC2231-related functions - parameter encoding and decoding
+def decode_rfc2231(s):
+ """Decode string according to RFC 2231"""
+ parts = s.split(TICK, 2)
+ if len(parts) <= 2:
+ return None, None, s
+ return parts
+
+
+def encode_rfc2231(s, charset=None, language=None):
+ """Encode string according to RFC 2231.
+
+ If neither charset nor language is given, then s is returned as-is. If
+ charset is given but not language, the string is encoded using the empty
+ string for language.
+ """
+ import urllib
+ s = urllib.quote(s, safe='')
+ if charset is None and language is None:
+ return s
+ if language is None:
+ language = ''
+ return "%s'%s'%s" % (charset, language, s)
+
+
+rfc2231_continuation = re.compile(r'^(?P<name>\w+)\*((?P<num>[0-9]+)\*?)?$')
+
+def decode_params(params):
+ """Decode parameters list according to RFC 2231.
+
+ params is a sequence of 2-tuples containing (param name, string value).
+ """
+ # Copy params so we don't mess with the original
+ params = params[:]
+ new_params = []
+ # Map parameter's name to a list of continuations. The values are a
+ # 3-tuple of the continuation number, the string value, and a flag
+ # specifying whether a particular segment is %-encoded.
+ rfc2231_params = {}
+ name, value = params.pop(0)
+ new_params.append((name, value))
+ while params:
+ name, value = params.pop(0)
+ if name.endswith('*'):
+ encoded = True
+ else:
+ encoded = False
+ value = unquote(value)
+ mo = rfc2231_continuation.match(name)
+ if mo:
+ name, num = mo.group('name', 'num')
+ if num is not None:
+ num = int(num)
+ rfc2231_params.setdefault(name, []).append((num, value, encoded))
+ else:
+ new_params.append((name, '"%s"' % quote(value)))
+ if rfc2231_params:
+ for name, continuations in rfc2231_params.items():
+ value = []
+ extended = False
+ # Sort by number
+ continuations.sort()
+ # And now append all values in numerical order, converting
+ # %-encodings for the encoded segments. If any of the
+ # continuation names ends in a *, then the entire string, after
+ # decoding segments and concatenating, must have the charset and
+ # language specifiers at the beginning of the string.
+ for num, s, encoded in continuations:
+ if encoded:
+ s = urllib.unquote(s)
+ extended = True
+ value.append(s)
+ value = quote(EMPTYSTRING.join(value))
+ if extended:
+ charset, language, value = decode_rfc2231(value)
+ new_params.append((name, (charset, language, '"%s"' % value)))
+ else:
+ new_params.append((name, '"%s"' % value))
+ return new_params
+
+def collapse_rfc2231_value(value, errors='replace',
+ fallback_charset='us-ascii'):
+ if not isinstance(value, tuple) or len(value) != 3:
+ return unquote(value)
+ # While value comes to us as a unicode string, we need it to be a bytes
+ # object. We do not want bytes() normal utf-8 decoder, we want a straight
+ # interpretation of the string as character bytes.
+ charset, language, text = value
+ rawbytes = bytes(ord(c) for c in text)
+ try:
+ return str(rawbytes, charset, errors)
+ except LookupError:
+ # charset is not a known codec.
+ return unquote(text)