382 lines
13 KiB
Python
382 lines
13 KiB
Python
# Copyright (C) 2001-2010 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',
|
|
'format_datetime',
|
|
'getaddresses',
|
|
'make_msgid',
|
|
'mktime_tz',
|
|
'parseaddr',
|
|
'parsedate',
|
|
'parsedate_tz',
|
|
'parsedate_to_datetime',
|
|
'unquote',
|
|
]
|
|
|
|
import os
|
|
import re
|
|
import time
|
|
import random
|
|
import socket
|
|
import datetime
|
|
import urllib.parse
|
|
|
|
from email._parseaddr import quote
|
|
from email._parseaddr import AddressList as _AddressList
|
|
from email._parseaddr import mktime_tz
|
|
|
|
from email._parseaddr import parsedate, parsedate_tz, _parsedate_tz
|
|
|
|
# Intrapackage imports
|
|
from email.charset import Charset
|
|
|
|
COMMASPACE = ', '
|
|
EMPTYSTRING = ''
|
|
UEMPTYSTRING = ''
|
|
CRLF = '\r\n'
|
|
TICK = "'"
|
|
|
|
specialsre = re.compile(r'[][\\()<>@,:;".]')
|
|
escapesre = re.compile(r'[\\"]')
|
|
|
|
def _has_surrogates(s):
|
|
"""Return True if s contains surrogate-escaped binary data."""
|
|
# This check is based on the fact that unless there are surrogates, utf8
|
|
# (Python's default encoding) can encode any string. This is the fastest
|
|
# way to check for surrogates, see issue 11454 for timings.
|
|
try:
|
|
s.encode()
|
|
return False
|
|
except UnicodeEncodeError:
|
|
return True
|
|
|
|
# How to deal with a string containing bytes before handing it to the
|
|
# application through the 'normal' interface.
|
|
def _sanitize(string):
|
|
# Turn any escaped bytes into unicode 'unknown' char. If the escaped
|
|
# bytes happen to be utf-8 they will instead get decoded, even if they
|
|
# were invalid in the charset the source was supposed to be in. This
|
|
# seems like it is not a bad thing; a defect was still registered.
|
|
original_bytes = string.encode('utf-8', 'surrogateescape')
|
|
return original_bytes.decode('utf-8', 'replace')
|
|
|
|
|
|
|
|
# Helpers
|
|
|
|
def formataddr(pair, charset='utf-8'):
|
|
"""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.
|
|
|
|
Optional charset if given is the character set that is used to encode
|
|
realname in case realname is not ASCII safe. Can be an instance of str or
|
|
a Charset-like object which has a header_encode method. Default is
|
|
'utf-8'.
|
|
"""
|
|
name, address = pair
|
|
# The address MUST (per RFC) be ascii, so raise an UnicodeError if it isn't.
|
|
address.encode('ascii')
|
|
if name:
|
|
try:
|
|
name.encode('ascii')
|
|
except UnicodeEncodeError:
|
|
if isinstance(charset, str):
|
|
charset = Charset(charset)
|
|
encoded_name = charset.header_encode(name)
|
|
return "%s <%s>" % (encoded_name, address)
|
|
else:
|
|
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 _format_timetuple_and_zone(timetuple, zone):
|
|
return '%s, %02d %s %04d %02d:%02d:%02d %s' % (
|
|
['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun'][timetuple[6]],
|
|
timetuple[2],
|
|
['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
|
|
'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'][timetuple[1] - 1],
|
|
timetuple[0], timetuple[3], timetuple[4], timetuple[5],
|
|
zone)
|
|
|
|
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 or usegmt:
|
|
dt = datetime.datetime.fromtimestamp(timeval, datetime.timezone.utc)
|
|
else:
|
|
dt = datetime.datetime.utcfromtimestamp(timeval)
|
|
if localtime:
|
|
dt = dt.astimezone()
|
|
usegmt = False
|
|
return format_datetime(dt, usegmt)
|
|
|
|
def format_datetime(dt, usegmt=False):
|
|
"""Turn a datetime into a date string as specified in RFC 2822.
|
|
|
|
If usegmt is True, dt must be an aware datetime with an offset of zero. In
|
|
this case 'GMT' will be rendered instead of the normal +0000 required by
|
|
RFC2822. This is to support HTTP headers involving date stamps.
|
|
"""
|
|
now = dt.timetuple()
|
|
if usegmt:
|
|
if dt.tzinfo is None or dt.tzinfo != datetime.timezone.utc:
|
|
raise ValueError("usegmt option requires a UTC datetime")
|
|
zone = 'GMT'
|
|
elif dt.tzinfo is None:
|
|
zone = '-0000'
|
|
else:
|
|
zone = dt.strftime("%z")
|
|
return _format_timetuple_and_zone(now, zone)
|
|
|
|
|
|
def make_msgid(idstring=None, domain=None):
|
|
"""Returns a string suitable for RFC 2822 compliant Message-ID, e.g:
|
|
|
|
<142480216486.20800.16526388040877946887@nightshade.la.mastaler.com>
|
|
|
|
Optional idstring if given is a string used to strengthen the
|
|
uniqueness of the message id. Optional domain if given provides the
|
|
portion of the message id after the '@'. It defaults to the locally
|
|
defined hostname.
|
|
"""
|
|
timeval = int(time.time()*100)
|
|
pid = os.getpid()
|
|
randint = random.getrandbits(64)
|
|
if idstring is None:
|
|
idstring = ''
|
|
else:
|
|
idstring = '.' + idstring
|
|
if domain is None:
|
|
domain = socket.getfqdn()
|
|
msgid = '<%d.%d.%d%s@%s>' % (timeval, pid, randint, idstring, domain)
|
|
return msgid
|
|
|
|
|
|
def parsedate_to_datetime(data):
|
|
*dtuple, tz = _parsedate_tz(data)
|
|
if tz is None:
|
|
return datetime.datetime(*dtuple[:6])
|
|
return datetime.datetime(*dtuple[:6],
|
|
tzinfo=datetime.timezone(datetime.timedelta(seconds=tz)))
|
|
|
|
|
|
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.
|
|
"""
|
|
s = urllib.parse.quote(s, safe='', encoding=charset or 'ascii')
|
|
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]+)\*?)?$',
|
|
re.ASCII)
|
|
|
|
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:
|
|
# Decode as "latin-1", so the characters in s directly
|
|
# represent the percent-encoded octet values.
|
|
# collapse_rfc2231_value treats this as an octet sequence.
|
|
s = urllib.parse.unquote(s, encoding="latin-1")
|
|
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
|
|
if charset is None:
|
|
# Issue 17369: if charset/lang is None, decode_rfc2231 couldn't parse
|
|
# the value, so use the fallback_charset.
|
|
charset = fallback_charset
|
|
rawbytes = bytes(text, 'raw-unicode-escape')
|
|
try:
|
|
return str(rawbytes, charset, errors)
|
|
except LookupError:
|
|
# charset is not a known codec.
|
|
return unquote(text)
|
|
|
|
|
|
#
|
|
# datetime doesn't provide a localtime function yet, so provide one. Code
|
|
# adapted from the patch in issue 9527. This may not be perfect, but it is
|
|
# better than not having it.
|
|
#
|
|
|
|
def localtime(dt=None, isdst=-1):
|
|
"""Return local time as an aware datetime object.
|
|
|
|
If called without arguments, return current time. Otherwise *dt*
|
|
argument should be a datetime instance, and it is converted to the
|
|
local time zone according to the system time zone database. If *dt* is
|
|
naive (that is, dt.tzinfo is None), it is assumed to be in local time.
|
|
In this case, a positive or zero value for *isdst* causes localtime to
|
|
presume initially that summer time (for example, Daylight Saving Time)
|
|
is or is not (respectively) in effect for the specified time. A
|
|
negative value for *isdst* causes the localtime() function to attempt
|
|
to divine whether summer time is in effect for the specified time.
|
|
|
|
"""
|
|
if dt is None:
|
|
return datetime.datetime.now(datetime.timezone.utc).astimezone()
|
|
if dt.tzinfo is not None:
|
|
return dt.astimezone()
|
|
# We have a naive datetime. Convert to a (localtime) timetuple and pass to
|
|
# system mktime together with the isdst hint. System mktime will return
|
|
# seconds since epoch.
|
|
tm = dt.timetuple()[:-1] + (isdst,)
|
|
seconds = time.mktime(tm)
|
|
localtm = time.localtime(seconds)
|
|
try:
|
|
delta = datetime.timedelta(seconds=localtm.tm_gmtoff)
|
|
tz = datetime.timezone(delta, localtm.tm_zone)
|
|
except AttributeError:
|
|
# Compute UTC offset and compare with the value implied by tm_isdst.
|
|
# If the values match, use the zone name implied by tm_isdst.
|
|
delta = dt - datetime.datetime(*time.gmtime(seconds)[:6])
|
|
dst = time.daylight and localtm.tm_isdst > 0
|
|
gmtoff = -(time.altzone if dst else time.timezone)
|
|
if delta == datetime.timedelta(seconds=gmtoff):
|
|
tz = datetime.timezone(delta, time.tzname[dst])
|
|
else:
|
|
tz = datetime.timezone(delta)
|
|
return dt.replace(tzinfo=tz)
|