:mod:`!imaplib` --- IMAP4 protocol client
=========================================

.. module:: imaplib
   :synopsis: IMAP4 protocol client (requires sockets).

**Source code:** :source:`Lib/imaplib.py`

.. index::
   pair: IMAP4; protocol
   pair: IMAP4_SSL; protocol
   pair: IMAP4_stream; protocol

--------------

This module defines three classes, :class:`IMAP4`, :class:`IMAP4_SSL` and
:class:`IMAP4_stream`, which encapsulate a connection to an IMAP4 server and
implement a large subset of the IMAP4rev1 client protocol as defined in
:rfc:`3501`. It is backward compatible with IMAP4 (:rfc:`1730`) servers, but
note that the ``STATUS`` command is not supported in IMAP4.

.. include:: ../includes/wasm-notavail.rst

Three classes are provided by the :mod:`!imaplib` module, :class:`IMAP4` is the
base class:


.. class:: IMAP4(host='', port=IMAP4_PORT, timeout=None)

   This class implements the actual IMAP4 protocol.  The connection is created and
   protocol version (IMAP4 or IMAP4rev1) is determined when the instance is
   initialized. If *host* is not specified, ``''`` (the local host) is used. If
   *port* is omitted, the standard IMAP4 port (143) is used. The optional *timeout*
   parameter specifies a timeout in seconds for the connection attempt.
   If timeout is not given or is ``None``, the global default socket timeout is used.

   The :class:`IMAP4` class supports the :keyword:`with` statement.  When used
   like this, the IMAP4 ``LOGOUT`` command is issued automatically when the
   :keyword:`!with` statement exits.  E.g.::

    >>> from imaplib import IMAP4
    >>> with IMAP4("domain.org") as M:
    ...     M.noop()
    ...
    ('OK', [b'Nothing Accomplished. d25if65hy903weo.87'])

   .. versionchanged:: 3.5
      Support for the :keyword:`with` statement was added.

   .. versionchanged:: 3.9
      The optional *timeout* parameter was added.

Three exceptions are defined as attributes of the :class:`IMAP4` class:


.. exception:: IMAP4.error

   Exception raised on any errors.  The reason for the exception is passed to the
   constructor as a string.


.. exception:: IMAP4.abort

   IMAP4 server errors cause this exception to be raised.  This is a sub-class of
   :exc:`IMAP4.error`.  Note that closing the instance and instantiating a new one
   will usually allow recovery from this exception.


.. exception:: IMAP4.readonly

   This exception is raised when a writable mailbox has its status changed by the
   server.  This is a sub-class of :exc:`IMAP4.error`.  Some other client now has
   write permission, and the mailbox will need to be re-opened to re-obtain write
   permission.


There's also a subclass for secure connections:


.. class:: IMAP4_SSL(host='', port=IMAP4_SSL_PORT, *, ssl_context=None, \
                     timeout=None)

   This is a subclass derived from :class:`IMAP4` that connects over an SSL
   encrypted socket (to use this class you need a socket module that was compiled
   with SSL support).  If *host* is not specified, ``''`` (the local host) is used.
   If *port* is omitted, the standard IMAP4-over-SSL port (993) is used.
   *ssl_context* is a :class:`ssl.SSLContext` object which allows bundling
   SSL configuration options, certificates and private keys into a single
   (potentially long-lived) structure.  Please read :ref:`ssl-security` for
   best practices.

   .. note::

      With the default *ssl_context*, the connection is encrypted but the
      server certificate and hostname are not verified.
      To verify them, pass a context created by
      :func:`ssl.create_default_context`.

   The optional *timeout* parameter specifies a timeout in seconds for the
   connection attempt. If timeout is not given or is ``None``, the global default
   socket timeout is used.

   .. versionchanged:: 3.3
      *ssl_context* parameter was added.

   .. versionchanged:: 3.4
      The class now supports hostname check with
      :attr:`ssl.SSLContext.check_hostname` and *Server Name Indication* (see
      :const:`ssl.HAS_SNI`).

   .. versionchanged:: 3.9
      The optional *timeout* parameter was added.

   .. versionchanged:: 3.12
      The deprecated *keyfile* and *certfile* parameters have been removed.

The second subclass allows for connections created by a child process:


.. class:: IMAP4_stream(command)

   This is a subclass derived from :class:`IMAP4` that connects to the
   ``stdin/stdout`` file descriptors created by passing *command* to
   ``subprocess.Popen()``.


The following utility functions are defined:


.. function:: Internaldate2tuple(resp)

   Parse a :term:`bytes-like object` containing an IMAP4 ``INTERNALDATE``
   response and return the corresponding local time.  The return value is a
   :class:`time.struct_time` tuple or ``None`` if the input has wrong format.

.. function:: Int2AP(num)

   Converts an integer into a bytes representation using characters from the set
   [``A`` .. ``P``].


.. function:: ParseFlags(resp)

   Converts a :term:`bytes-like object` containing an IMAP4 ``FLAGS`` response
   to a tuple of individual flags as :class:`bytes`.  The return value is an
   empty tuple if the input has wrong format.


.. function:: Time2Internaldate(date_time)

   Convert *date_time* to an IMAP4 ``INTERNALDATE`` representation.
   The return value is a string in the form: ``"DD-Mmm-YYYY HH:MM:SS
   +HHMM"`` (including double-quotes).  The *date_time* argument can
   be a number (int or float) representing seconds since epoch (as
   returned by :func:`time.time`), a 9-tuple representing local time
   an instance of :class:`time.struct_time` (as returned by
   :func:`time.localtime`), an aware instance of
   :class:`datetime.datetime`, or a double-quoted string.  In the last
   case, it is assumed to already be in the correct format.

Note that IMAP4 message numbers change as the mailbox changes; in particular,
after an ``EXPUNGE`` command performs deletions the remaining messages are
renumbered. So it is highly advisable to use UIDs instead, with the UID command.

At the end of the module, there is a test section that contains a more extensive
example of usage.


.. seealso::

   Documents describing the protocol, sources for servers
   implementing it, by the University of Washington's IMAP Information Center
   can all be found at (**Source Code**) https://github.com/uw-imap/imap (**Not Maintained**).


.. _imap4-objects:

IMAP4 Objects
-------------

All IMAP4rev1 commands are represented by methods of the same name, either
uppercase or lowercase.

All arguments to commands are converted to strings, except for ``AUTHENTICATE``,
and the last argument to ``APPEND`` which is passed as an IMAP4 literal.  If
necessary (the string contains IMAP4 protocol-sensitive characters and isn't
enclosed with either parentheses or double quotes) each string is quoted.
However, the *password* argument to the ``LOGIN`` command is always quoted. If
you want to avoid having an argument string quoted (eg: the *flags* argument to
``STORE``) then enclose the string in parentheses (eg: ``r'(\Deleted)'``).
Or you can quote the string yourself;
an argument that is already enclosed in double quotes is left unchanged.
In general, however, it is better to pass arguments unquoted
and let the module quote them as needed.

Mailbox names are encoded as modified UTF-7 (:rfc:`3501`, section 5.1.3),
so a mailbox name containing non-ASCII characters can be passed as an
ordinary :class:`str`.
A :class:`str` that is already valid modified UTF-7 is left unchanged,
so that a name obtained from :meth:`~IMAP4.list` (raw ``bytes`` decoded to
text) round-trips; pass :class:`bytes` to send the exact bytes with no
encoding.
When ``UTF8=ACCEPT`` is enabled (see :meth:`~IMAP4.enable`), mailbox names
are sent as UTF-8 instead.

.. versionchanged:: next
   Non-ASCII mailbox names are automatically encoded as modified UTF-7.

Most commands return a tuple: ``(type, [data, ...])`` where *type* is usually
``'OK'`` or ``'NO'``, and *data* is either the text from the command response,
or mandated results from the command. Each *data* is either a ``bytes``, or a
tuple. If a tuple, then the first part is the header of the response, and the
second part contains the data (ie: 'literal' value).

The *message_set* options to the commands below can be a string specifying
one or more messages to be acted upon.
It may be a simple message number (``'1'``),
a range of message numbers (``'2:4'``),
or a group of non-contiguous ranges separated by commas (``'1:3,6:9'``).
A range can contain an asterisk
to indicate an infinite upper bound (``'3:*'``).

Alternatively it can be specified using integers and :class:`range` objects.
It may be a single message number or a sequence.
The sequence items may be integers, ``(start, stop)`` tuples
(where ``None`` or ``'*'`` stands for the last message),
or :class:`range` objects.
For example, ``[1, (3, 5), 8]`` and ``[range(1, 6), 8]``
are both equivalent to ``'1,3:5,8'``.

.. versionchanged:: next
   Added support for the structured *message_set*.

Command arguments that are parenthesized lists of atoms ---
such as the *flag_list* argument of :meth:`~IMAP4.store` and the *flags*
argument of :meth:`~IMAP4.append`,
the *names* argument of :meth:`~IMAP4.status`,
the *sort_criteria* argument of :meth:`~IMAP4.sort`,
or the *message_parts* argument of :meth:`~IMAP4.fetch` ---
can be passed as a sequence of strings instead of a single preformatted string.
For example, ``[r'\Seen', r'\Answered']``
is equivalent to ``(\Seen \Answered)``.

.. versionchanged:: next
   Added support for passing these arguments as a sequence.

.. _imap4-params:

The value-bearing arguments of the search and fetch commands
can be quoted by hand, but this is error prone.
Instead, they may contain ``?`` placeholders that are substituted, and quoted
as required, from a *params* keyword argument,
in the manner of :mod:`sqlite3` parameter substitution::

   # SEARCH FROM me@example.com SUBJECT "trip report"
   M.search(None, 'FROM ? SUBJECT ?', params=['me@example.com', 'trip report'])

   # FETCH 1:5 (FLAGS BODY[HEADER.FIELDS (DATE FROM)])
   M.fetch('1:5', 'FLAGS BODY[HEADER.FIELDS ?]', params=[['DATE', 'FROM']])

The placeholders are:

* ``?`` --- an ``astring``: a string (which will be quoted if necessary),
  an integer, or a list of integers and/or strings
  (which will be sent as a parenthesized list);
* ``?f`` --- a flag or a list of flags, sent verbatim without quoting;
* ``?s`` --- a *message_set* in the structured form described above.

``??`` stands for a literal ``?``.

Substitution is only performed when *params* is given;
if no *params* are given, an argument containing a literal ``?`` is unchanged.
The *params* keyword is accepted by :meth:`~IMAP4.search`,
:meth:`~IMAP4.fetch`, :meth:`~IMAP4.sort`, :meth:`~IMAP4.thread` and
:meth:`~IMAP4.uid`.

.. versionadded:: next
   The *params* keyword argument.

An :class:`IMAP4` instance has the following methods:


.. method:: IMAP4.append(mailbox, flags, date_time, message, *, translate_line_endings=True)

   Append *message* to named mailbox.

   *flags* may be ``None`` or a string of IMAP flag tokens.  Multiple
   flags are separated by spaces, for example ``r'\Seen \Answered'``.
   If *flags* is not already enclosed in parentheses, parentheses are
   added automatically.

   If *translate_line_endings* is true (the default),
   line endings in *message* are translated to CRLF.
   Pass ``False`` to send the message literal exactly as given,
   which is required to preserve messages that contain bare CR or LF.
   In that case *message* must already use CRLF line endings as required
   by :rfc:`3501`; for example, serialize :mod:`email` messages using
   :class:`email.policy.SMTP`.

   .. versionchanged:: next
      Added the *translate_line_endings* parameter.


.. method:: IMAP4.authenticate(mechanism, authobject)

   Authenticate command --- requires response processing.

   *mechanism* specifies which authentication mechanism is to be used - it should
   appear in the instance variable ``capabilities`` in the form ``AUTH=mechanism``.

   *authobject* must be a callable object::

      data = authobject(response)

   It will be called to process server continuation responses; the *response*
   argument it is passed will be ``bytes``.  It should return ``bytes`` *data*
   that will be base64 encoded and sent to the server.  It should return
   ``None`` if the client abort response ``*`` should be sent instead.

   .. versionchanged:: 3.5
      string usernames and passwords are now encoded to ``utf-8`` instead of
      being limited to ASCII.


.. method:: IMAP4.check()

   Checkpoint mailbox on server.


.. method:: IMAP4.close()

   Close currently selected mailbox. Deleted messages are removed from writable
   mailbox. This is the recommended command before ``LOGOUT``.


.. method:: IMAP4.copy(message_set, new_mailbox, *, uid=False)

   Copy *message_set* messages onto end of *new_mailbox*.

   If *uid* is true, *message_set* is a set of UIDs and the ``UID COPY``
   command is used instead of ``COPY``.

   .. versionchanged:: next
      Added the *uid* parameter.


.. method:: IMAP4.create(mailbox)

   Create new mailbox named *mailbox*.


.. method:: IMAP4.delete(mailbox)

   Delete old mailbox named *mailbox*.


.. method:: IMAP4.deleteacl(mailbox, who)

   Delete the ACLs (remove any rights) set for who on mailbox.


.. method:: IMAP4.enable(capability)

   Enable *capability* (see :rfc:`5161`).  Most capabilities do not need to be
   enabled.  Currently only the ``UTF8=ACCEPT`` capability is supported
   (see :RFC:`6855`).

   .. versionadded:: 3.5
      The :meth:`enable` method itself, and :RFC:`6855` support.


.. method:: IMAP4.expunge(message_set=None, *, uid=False)

   Permanently remove deleted items from selected mailbox. Generates an ``EXPUNGE``
   response for each deleted message. Returned data contains a list of ``EXPUNGE``
   message numbers in order received.

   If *uid* is true, the ``UID EXPUNGE`` command (:rfc:`4315`) is used to remove
   only the messages that both are marked as deleted and have a UID in
   *message_set*.  *message_set* is required in this case, and must be omitted
   otherwise.

   .. versionchanged:: next
      Added the *message_set* and *uid* parameters.


.. method:: IMAP4.fetch(message_set, message_parts, *, uid=False, params=None)

   Fetch (parts of) messages.  *message_parts* should be a string of message part
   names enclosed within parentheses, eg: ``"(UID BODY[TEXT])"``.  Returned data
   are tuples of message part envelope and data.

   If *uid* is true, *message_set* is a set of UIDs and the message numbers in
   the response are UIDs (``UID FETCH``).

   If *params* is given, ``?`` placeholders in *message_parts* are substituted
   with the quoted parameters (see :ref:`the placeholders <imap4-params>`).

   .. versionchanged:: next
      Added the *params* and *uid* parameters.


.. method:: IMAP4.getacl(mailbox)

   Get the ``ACL``\ s for *mailbox*. The method is non-standard, but is supported
   by the ``Cyrus`` server.


.. method:: IMAP4.getannotation(mailbox, entry, attribute)

   Retrieve the specified ``ANNOTATION``\ s for *mailbox*. The method is
   non-standard, but is supported by the ``Cyrus`` server.


.. method:: IMAP4.getquota(root)

   Get the ``quota`` *root*'s resource usage and limits. This method is part of the
   IMAP4 QUOTA extension defined in rfc2087.


.. method:: IMAP4.getquotaroot(mailbox)

   Get the list of ``quota`` ``roots`` for the named *mailbox*. This method is part
   of the IMAP4 QUOTA extension defined in rfc2087.


.. method:: IMAP4.id(fields=None)

   Send client identification information to the server
   and return the identification information sent back by the server
   (the ``ID`` command, defined in :rfc:`2971`).
   *fields* is a mapping of field names to values
   (for example, ``{'name': 'myclient', 'version': '1.0'}``);
   a value can be ``None``.
   The server must support the ``ID`` capability.

   .. versionadded:: next


.. method:: IMAP4.idle(duration=None)

   Return an :class:`!Idler`: an iterable context manager implementing the
   IMAP4 ``IDLE`` command as defined in :rfc:`2177`.

   The returned object sends the ``IDLE`` command when activated by the
   :keyword:`with` statement, produces IMAP untagged responses via the
   :term:`iterator` protocol, and sends ``DONE`` upon context exit.

   All untagged responses that arrive after sending the ``IDLE`` command
   (including any that arrive before the server acknowledges the command) will
   be available via iteration. Any leftover responses (those not iterated in
   the :keyword:`with` context) can be retrieved in the usual way after
   ``IDLE`` ends, using :meth:`IMAP4.response`.

   Responses are represented as ``(type, [data, ...])`` tuples, as described
   in :ref:`IMAP4 Objects <imap4-objects>`.

   The *duration* argument sets a maximum duration (in seconds) to keep idling,
   after which any ongoing iteration will stop. It can be an :class:`int` or
   :class:`float`, or ``None`` for no time limit.
   Callers wishing to avoid inactivity timeouts on servers that impose them
   should keep this at most 29 minutes (1740 seconds).
   Requires a socket connection; *duration* must be ``None`` on
   :class:`IMAP4_stream` connections.

   .. code-block:: pycon

      >>> with M.idle(duration=29 * 60) as idler:
      ...     for typ, data in idler:
      ...         print(typ, data)
      ...
      EXISTS [b'1']
      RECENT [b'1']


   .. method:: Idler.burst(interval=0.1)

      Yield a burst of responses no more than *interval* seconds apart
      (expressed as an :class:`int` or :class:`float`).

      This :term:`generator` is an alternative to iterating one response at a
      time, intended to aid in efficient batch processing. It retrieves the
      next response along with any immediately available subsequent responses.
      (For example, a rapid series of ``EXPUNGE`` responses after a bulk
      delete.)

      Requires a socket connection; does not work on :class:`IMAP4_stream`
      connections.

      .. code-block:: pycon

         >>> with M.idle() as idler:
         ...     # get a response and any others following by < 0.1 seconds
         ...     batch = list(idler.burst())
         ...     print(f'processing {len(batch)} responses...')
         ...     print(batch)
         ...
         processing 3 responses...
         [('EXPUNGE', [b'2']), ('EXPUNGE', [b'1']), ('RECENT', [b'0'])]

      .. tip::

         The ``IDLE`` context's maximum duration, as passed to
         :meth:`IMAP4.idle`, is respected when waiting for the first response
         in a burst. Therefore, an expired :class:`!Idler` will cause this
         generator to return immediately without producing anything. Callers
         should consider this if using it in a loop.


   .. note::

      The iterator returned by :meth:`IMAP4.idle` is usable only within a
      :keyword:`with` statement. Before or after that context, unsolicited
      responses are collected internally whenever a command finishes, and can
      be retrieved with :meth:`IMAP4.response`.

   .. note::

      The :class:`!Idler` class name and structure are internal interfaces,
      subject to change. Calling code can rely on its context management,
      iteration, and public method to remain stable, but should not subclass,
      instantiate, compare, or otherwise directly reference the class.

   .. versionadded:: 3.14


.. method:: IMAP4.list(directory='', pattern='*')

   List mailbox names in *directory* matching *pattern*.  *directory* defaults to
   the top-level mail folder, and *pattern* defaults to match anything.  Returned
   data contains a list of ``LIST`` responses.


.. method:: IMAP4.login(user, password)

   Identify the client using a plaintext password. The *password* will be quoted.


.. method:: IMAP4.login_cram_md5(user, password)

   Force use of ``CRAM-MD5`` authentication when identifying the client to protect
   the password. It will only work if the server ``CAPABILITY`` response includes
   the phrase ``AUTH=CRAM-MD5``.

   .. versionchanged:: 3.15
      An :exc:`IMAP4.error` is raised if MD5 support is not available.


.. method:: IMAP4.login_plain(user, password)

   Authenticate using the ``PLAIN`` SASL mechanism (:rfc:`4616`).

   This is a plaintext authentication mechanism that can be used instead
   of :meth:`login` when UTF-8 support is required (see :rfc:`6855`).
   Since the credentials are only base64-encoded, not encrypted, this
   method should only be used over a TLS-protected connection, such as
   :class:`IMAP4_SSL` or after :meth:`starttls`.

   It will only work if the server supports the ``PLAIN`` mechanism,
   which it need not advertise as ``AUTH=PLAIN`` in its ``CAPABILITY``
   response.

   .. versionadded:: next


.. method:: IMAP4.logout()

   Shutdown connection to server. Returns server ``BYE`` response.

   .. versionchanged:: 3.8
      The method no longer ignores silently arbitrary exceptions.


.. method:: IMAP4.lsub(directory='', pattern='*')

   List subscribed mailbox names in directory matching pattern. *directory*
   defaults to the top level directory and *pattern* defaults to match any mailbox.
   Returned data are tuples of message part envelope and data.


.. method:: IMAP4.move(message_set, new_mailbox, *, uid=False)

   Move *message_set* messages onto end of *new_mailbox*.

   The server must support the ``MOVE`` capability (:rfc:`6851`).

   If *uid* is true, *message_set* is a set of UIDs and the ``UID MOVE``
   command is used instead of ``MOVE``.

   .. versionadded:: next


.. method:: IMAP4.myrights(mailbox)

   Show my ACLs for a mailbox (i.e. the rights that I have on mailbox).


.. method:: IMAP4.namespace()

   Returns IMAP namespaces as defined in :rfc:`2342`.


.. method:: IMAP4.noop()

   Send ``NOOP`` to server.


.. method:: IMAP4.open(host, port, timeout=None)

   Opens socket to *port* at *host*. The optional *timeout* parameter
   specifies a timeout in seconds for the connection attempt.
   If timeout is not given or is ``None``, the global default socket timeout
   is used. Also note that if the *timeout* parameter is set to be zero,
   it will raise a :class:`ValueError` to reject creating a non-blocking socket.
   This method is implicitly called by the :class:`IMAP4` constructor.
   The connection objects established by this method will be used in
   the :meth:`IMAP4.read`, :meth:`IMAP4.readline`, :meth:`IMAP4.send`,
   and :meth:`IMAP4.shutdown` methods. You may override this method.

   .. audit-event:: imaplib.open self,host,port imaplib.IMAP4.open

   .. versionchanged:: 3.9
      The *timeout* parameter was added.

.. method:: IMAP4.partial(message_num, message_part, start, length)

   Fetch truncated part of a message. Returned data is a tuple of message part
   envelope and data.


.. method:: IMAP4.proxyauth(user)

   Assume authentication as *user*. Allows an authorised administrator to proxy
   into any user's mailbox.


.. method:: IMAP4.read(size)

   Reads *size* bytes from the remote server. You may override this method.


.. method:: IMAP4.readline()

   Reads one line from the remote server. You may override this method.


.. method:: IMAP4.recent()

   Prompt server for an update. Returned data is ``None`` if no new messages, else
   value of ``RECENT`` response.


.. method:: IMAP4.rename(oldmailbox, newmailbox)

   Rename mailbox named *oldmailbox* to *newmailbox*.


.. method:: IMAP4.response(code)

   Return data for response *code* if received, or ``None``. Returns the given
   code, instead of the usual type.


.. method:: IMAP4.search(charset, criterion[, ...], *, uid=False, params=None)

   Search mailbox for matching messages.  *charset* may be ``None``, in which case
   no ``CHARSET`` will be specified in the request to the server.  The IMAP
   protocol requires that at least one criterion be specified; an exception will be
   raised when the server returns an error.  *charset* must be ``None`` if
   the ``UTF8=ACCEPT`` capability was enabled using the :meth:`enable`
   command.

   If *uid* is true, the message numbers in the response are UIDs
   (``UID SEARCH``).

   A criterion passed as :class:`str` is encoded to *charset*
   (which must name a codec known to Python);
   pass :class:`bytes` to send a criterion that is already encoded,
   for example when *charset* is one that Python does not support.
   When *charset* is ``None`` (as it must be under ``UTF8=ACCEPT``),
   the criterion is sent using the connection's encoding instead.

   If *params* is given, ``?`` placeholders in the criteria are substituted
   with the quoted parameters (see :ref:`the placeholders <imap4-params>`).

   Example::

      # M is a connected IMAP4 instance...
      typ, msgnums = M.search(None, 'FROM', '"John Smith"')

      # or:
      typ, msgnums = M.search(None, '(FROM "John Smith")')

      # or, letting the module quote the value (this is recommended):
      typ, msgnums = M.search(None, 'FROM ?', params=['John Smith'])

   .. versionchanged:: next
      Added the *params* and *uid* parameters.
      ``str`` search criteria are encoded to *charset*.


.. method:: IMAP4.select(mailbox='INBOX', readonly=False)

   Select a mailbox. Returned data is the count of messages in *mailbox*
   (``EXISTS`` response).  The default *mailbox* is ``'INBOX'``.  If the *readonly*
   flag is set, modifications to the mailbox are not allowed.


.. method:: IMAP4.send(data)

   Sends ``data`` to the remote server. You may override this method.

   .. audit-event:: imaplib.send self,data imaplib.IMAP4.send


.. method:: IMAP4.setacl(mailbox, who, what)

   Set an ``ACL`` for *mailbox*. The method is non-standard, but is supported by
   the ``Cyrus`` server.


.. method:: IMAP4.setannotation(mailbox, entry, attribute[, ...])

   Set ``ANNOTATION``\ s for *mailbox*. The method is non-standard, but is
   supported by the ``Cyrus`` server.


.. method:: IMAP4.setquota(root, limits)

   Set the ``quota`` *root*'s resource *limits*. This method is part of the IMAP4
   QUOTA extension defined in rfc2087.


.. method:: IMAP4.shutdown()

   Close connection established in ``open``.  This method is implicitly
   called by :meth:`IMAP4.logout`.  You may override this method.


.. method:: IMAP4.socket()

   Returns socket instance used to connect to server.


.. method:: IMAP4.sort(sort_criteria, charset, search_criterion[, ...], *, uid=False, params=None)

   The ``sort`` command is a variant of ``search`` with sorting semantics for the
   results.  Returned data contains a space separated list of matching message
   numbers.

   Sort has two arguments before the *search_criterion* argument(s); a
   parenthesized list of *sort_criteria*, and the searching *charset*.  Note that
   unlike ``search``, the searching *charset* argument is mandatory.  There is also
   a ``uid sort`` command which corresponds to ``sort`` the way that ``uid search``
   corresponds to ``search``.  The ``sort`` command first searches the mailbox for
   messages that match the given searching criteria using the charset argument for
   the interpretation of strings in the searching criteria.  It then returns the
   numbers of matching messages.

   If *uid* is true, the message numbers in the response are UIDs (``UID SORT``).

   As with :meth:`search`,
   a *search_criterion* passed as :class:`str` is encoded to *charset*;
   pass :class:`bytes` to send one already encoded.

   If *params* is given, ``?`` placeholders in the search criteria are
   substituted with the quoted parameters (see :ref:`the placeholders <imap4-params>`).

   This is an ``IMAP4rev1`` extension command.

   .. versionchanged:: next
      Added the *params* and *uid* parameters.
      ``str`` search criteria are encoded to *charset*.


.. method:: IMAP4.starttls(ssl_context=None)

   Send a ``STARTTLS`` command.  The *ssl_context* argument is optional
   and should be a :class:`ssl.SSLContext` object.  This will enable
   encryption on the IMAP connection.  Please read :ref:`ssl-security` for
   best practices.

   .. note::

      With the default *ssl_context*, the connection is encrypted but the
      server certificate and hostname are not verified.
      To verify them, pass a context created by
      :func:`ssl.create_default_context`.

   .. versionadded:: 3.2

   .. versionchanged:: 3.4
      The method now supports hostname check with
      :attr:`ssl.SSLContext.check_hostname` and *Server Name Indication* (see
      :const:`ssl.HAS_SNI`).


.. method:: IMAP4.status(mailbox, names)

   Request named status conditions for *mailbox*.


.. method:: IMAP4.store(message_set, command, flag_list, *, uid=False)

   Alters flag dispositions for messages in mailbox.  *command* is specified by
   section 6.4.6 of :rfc:`3501` as being one of "FLAGS", "+FLAGS", or "-FLAGS",
   optionally with a suffix of ".SILENT".

   If *uid* is true, *message_set* is a set of UIDs and the ``UID STORE``
   command is used instead of ``STORE``.

   For example, to set the delete flag on all messages::

      typ, data = M.search(None, 'ALL')
      for num in data[0].split():
         M.store(num, '+FLAGS', r'\Deleted')
      M.expunge()

   .. note::

      Creating flags containing ']' (for example: "[test]") violates
      :rfc:`3501` (the IMAP protocol).  However, imaplib has historically
      allowed creation of such flags, and popular IMAP servers, such as Gmail,
      accept and produce such flags.  There are non-Python programs which also
      create such flags.  Although it is an RFC violation and IMAP clients and
      servers are supposed to be strict, imaplib still continues to allow
      such flags to be created for backward compatibility reasons, and as of
      Python 3.6, handles them if they are sent from the server, since this
      improves real-world compatibility.

   .. versionchanged:: next
      Added the *uid* parameter.

.. method:: IMAP4.subscribe(mailbox)

   Subscribe to new mailbox.


.. method:: IMAP4.thread(threading_algorithm, charset, search_criterion[, ...], *, uid=False, params=None)

   The ``thread`` command is a variant of ``search`` with threading semantics for
   the results.  Returned data contains a space separated list of thread members.

   Thread members consist of zero or more messages numbers, delimited by spaces,
   indicating successive parent and child.

   Thread has two arguments before the *search_criterion* argument(s); a
   *threading_algorithm*, and the searching *charset*.  Note that unlike
   ``search``, the searching *charset* argument is mandatory.  There is also a
   ``uid thread`` command which corresponds to ``thread`` the way that ``uid
   search`` corresponds to ``search``.  The ``thread`` command first searches the
   mailbox for messages that match the given searching criteria using the *charset*
   argument for the interpretation of strings in the searching criteria. It then
   returns the matching messages threaded according to the specified threading
   algorithm.

   If *uid* is true, the message numbers in the response are UIDs
   (``UID THREAD``).

   As with :meth:`search`,
   a *search_criterion* passed as :class:`str` is encoded to *charset*;
   pass :class:`bytes` to send one already encoded.

   If *params* is given, ``?`` placeholders in the search criteria are
   substituted with the quoted parameters (see :ref:`the placeholders <imap4-params>`).

   This is an ``IMAP4rev1`` extension command.

   .. versionchanged:: next
      Added the *params* and *uid* parameters.
      ``str`` search criteria are encoded to *charset*.


.. method:: IMAP4.uid(command, arg[, ...], *, params=None)

   Execute command args with messages identified by UID, rather than message
   number.  Returns response appropriate to command.  At least one argument must be
   supplied; if none are provided, the server will return an error and an exception
   will be raised.

   If *params* is given, ``?`` placeholders in the ``SEARCH``, ``SORT`` and
   ``THREAD`` criteria or in the ``FETCH`` parts are substituted with the quoted
   parameters (see :ref:`the placeholders <imap4-params>`).

   .. versionchanged:: next
      Added the *params* parameter.


.. method:: IMAP4.unsubscribe(mailbox)

   Unsubscribe from old mailbox.

.. method:: IMAP4.unselect()

   :meth:`imaplib.IMAP4.unselect` frees server's resources associated with the
   selected mailbox and returns the server to the authenticated
   state. This command performs the same actions as :meth:`imaplib.IMAP4.close`, except
   that no messages are permanently removed from the currently
   selected mailbox.

   .. versionadded:: 3.9

.. method:: IMAP4.xatom(name[, ...])

   Allow simple extension commands notified by server in ``CAPABILITY`` response.


The following attributes are defined on instances of :class:`IMAP4`:

.. attribute:: IMAP4.PROTOCOL_VERSION

   The most recent supported protocol in the ``CAPABILITY`` response from the
   server.


.. attribute:: IMAP4.debug

   Integer value to control debugging output.  The initialize value is taken from
   the module variable ``Debug``.  Values greater than three trace each command.


.. attribute:: IMAP4.utf8_enabled

   Boolean value that is normally ``False``, but is set to ``True`` if an
   :meth:`enable` command is successfully issued for the ``UTF8=ACCEPT``
   capability.

   .. versionadded:: 3.5


.. property:: IMAP4.file

   Internal :class:`~io.BufferedReader` associated with the underlying socket.
   This property is documented for legacy purposes but not part of the public
   interface. The caller is responsible to ensure that the current file is
   closed before changing it.

   .. deprecated-removed:: 3.15 3.19


.. _imap4-example:

IMAP4 Example
-------------

Here is a minimal example (without error checking) that opens a mailbox and
retrieves and prints all messages::

   import getpass, imaplib

   M = imaplib.IMAP4(host='example.org')
   M.login(getpass.getuser(), getpass.getpass())
   M.select()
   typ, data = M.search(None, 'ALL')
   for num in data[0].split():
       typ, data = M.fetch(num, '(RFC822)')
       print('Message %s\n%s\n' % (num, data[0][1]))
   M.close()
   M.logout()

.. note::

   A ``FETCH`` response may contain additional or unsolicited data
   (see :rfc:`3501`, section 7.4.2),
   so production code should inspect the whole response
   rather than rely on ``data[0][1]``.

