| :mod:`email`: Miscellaneous utilities |
| ------------------------------------- |
| |
| .. module:: email.utils |
| :synopsis: Miscellaneous email package utilities. |
| |
| |
| There are several useful utilities provided in the :mod:`email.utils` module: |
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| .. function:: quote(str) |
| |
| Return a new string with backslashes in *str* replaced by two backslashes, and |
| double quotes replaced by backslash-double quote. |
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| .. function:: unquote(str) |
| |
| Return a new string which is an *unquoted* version of *str*. If *str* ends and |
| begins with double quotes, they are stripped off. Likewise if *str* ends and |
| begins with angle brackets, they are stripped off. |
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| .. function:: parseaddr(address) |
| |
| Parse address -- which should be the value of some address-containing field such |
| as :mailheader:`To` or :mailheader:`Cc` -- into its constituent *realname* and |
| *email address* parts. Returns a tuple of that information, unless the parse |
| fails, in which case a 2-tuple of ``('', '')`` is returned. |
| |
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| .. function:: formataddr(pair) |
| |
| The inverse of :meth:`parseaddr`, this takes a 2-tuple of the form ``(realname, |
| email_address)`` and returns the string value suitable for a :mailheader:`To` or |
| :mailheader:`Cc` header. If the first element of *pair* is false, then the |
| second element is returned unmodified. |
| |
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| .. function:: getaddresses(fieldvalues) |
| |
| This method returns a list of 2-tuples of the form returned by ``parseaddr()``. |
| *fieldvalues* is a sequence of header field values as might be returned by |
| :meth:`Message.get_all`. Here's a simple example that gets all the recipients |
| of a message:: |
| |
| from email.utils import getaddresses |
| |
| tos = msg.get_all('to', []) |
| ccs = msg.get_all('cc', []) |
| resent_tos = msg.get_all('resent-to', []) |
| resent_ccs = msg.get_all('resent-cc', []) |
| all_recipients = getaddresses(tos + ccs + resent_tos + resent_ccs) |
| |
| |
| .. function:: parsedate(date) |
| |
| Attempts to parse a date according to the rules in :rfc:`2822`. however, some |
| mailers don't follow that format as specified, so :func:`parsedate` tries to |
| guess correctly in such cases. *date* is a string containing an :rfc:`2822` |
| date, such as ``"Mon, 20 Nov 1995 19:12:08 -0500"``. If it succeeds in parsing |
| the date, :func:`parsedate` returns a 9-tuple that can be passed directly to |
| :func:`time.mktime`; otherwise ``None`` will be returned. Note that indexes 6, |
| 7, and 8 of the result tuple are not usable. |
| |
| |
| .. function:: parsedate_tz(date) |
| |
| Performs the same function as :func:`parsedate`, but returns either ``None`` or |
| a 10-tuple; the first 9 elements make up a tuple that can be passed directly to |
| :func:`time.mktime`, and the tenth is the offset of the date's timezone from UTC |
| (which is the official term for Greenwich Mean Time) [#]_. If the input string |
| has no timezone, the last element of the tuple returned is ``None``. Note that |
| indexes 6, 7, and 8 of the result tuple are not usable. |
| |
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| .. function:: mktime_tz(tuple) |
| |
| Turn a 10-tuple as returned by :func:`parsedate_tz` into a UTC timestamp. It |
| the timezone item in the tuple is ``None``, assume local time. Minor |
| deficiency: :func:`mktime_tz` interprets the first 8 elements of *tuple* as a |
| local time and then compensates for the timezone difference. This may yield a |
| slight error around changes in daylight savings time, though not worth worrying |
| about for common use. |
| |
| |
| .. function:: formatdate(timeval=None, localtime=False, usegmt=False) |
| |
| Returns a date string as per :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 |
| :func:`time.gmtime` and :func:`time.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. The default is ``False`` meaning UTC is |
| used. |
| |
| Optional *usegmt* is a flag that when ``True``, outputs a date string with the |
| timezone as an ascii string ``GMT``, rather than a numeric ``-0000``. This is |
| needed for some protocols (such as HTTP). This only applies when *localtime* is |
| ``False``. The default is ``False``. |
| |
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| .. function:: make_msgid(idstring=None) |
| |
| Returns a string suitable for an :rfc:`2822`\ -compliant |
| :mailheader:`Message-ID` header. Optional *idstring* if given, is a string |
| used to strengthen the uniqueness of the message id. |
| |
| |
| .. function:: decode_rfc2231(s) |
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| Decode the string *s* according to :rfc:`2231`. |
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| .. function:: encode_rfc2231(s, charset=None, language=None) |
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| Encode the string *s* according to :rfc:`2231`. Optional *charset* and |
| *language*, if given is the character set name and language name to use. If |
| neither is given, *s* is returned as-is. If *charset* is given but *language* |
| is not, the string is encoded using the empty string for *language*. |
| |
| |
| .. function:: collapse_rfc2231_value(value, errors='replace', fallback_charset='us-ascii') |
| |
| When a header parameter is encoded in :rfc:`2231` format, |
| :meth:`Message.get_param` may return a 3-tuple containing the character set, |
| language, and value. :func:`collapse_rfc2231_value` turns this into a unicode |
| string. Optional *errors* is passed to the *errors* argument of :class:`str`'s |
| :func:`encode` method; it defaults to ``'replace'``. Optional |
| *fallback_charset* specifies the character set to use if the one in the |
| :rfc:`2231` header is not known by Python; it defaults to ``'us-ascii'``. |
| |
| For convenience, if the *value* passed to :func:`collapse_rfc2231_value` is not |
| a tuple, it should be a string and it is returned unquoted. |
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| .. function:: decode_params(params) |
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| Decode parameters list according to :rfc:`2231`. *params* is a sequence of |
| 2-tuples containing elements of the form ``(content-type, string-value)``. |
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| .. rubric:: Footnotes |
| |
| .. [#] Note that the sign of the timezone offset is the opposite of the sign of the |
| ``time.timezone`` variable for the same timezone; the latter variable follows |
| the POSIX standard while this module follows :rfc:`2822`. |
| |