| :mod:`mailbox` --- Manipulate mailboxes in various formats |
| ========================================================== |
| |
| .. module:: mailbox |
| :synopsis: Manipulate mailboxes in various formats |
| .. moduleauthor:: Gregory K. Johnson <gkj@gregorykjohnson.com> |
| .. sectionauthor:: Gregory K. Johnson <gkj@gregorykjohnson.com> |
| |
| |
| This module defines two classes, :class:`Mailbox` and :class:`Message`, for |
| accessing and manipulating on-disk mailboxes and the messages they contain. |
| :class:`Mailbox` offers a dictionary-like mapping from keys to messages. |
| :class:`Message` extends the :mod:`email.Message` module's :class:`Message` |
| class with format-specific state and behavior. Supported mailbox formats are |
| Maildir, mbox, MH, Babyl, and MMDF. |
| |
| |
| .. seealso:: |
| |
| Module :mod:`email` |
| Represent and manipulate messages. |
| |
| |
| .. _mailbox-objects: |
| |
| :class:`Mailbox` objects |
| ------------------------ |
| |
| .. class:: Mailbox |
| |
| A mailbox, which may be inspected and modified. |
| |
| The :class:`Mailbox` class defines an interface and is not intended to be |
| instantiated. Instead, format-specific subclasses should inherit from |
| :class:`Mailbox` and your code should instantiate a particular subclass. |
| |
| The :class:`Mailbox` interface is dictionary-like, with small keys |
| corresponding to messages. Keys are issued by the :class:`Mailbox` instance |
| with which they will be used and are only meaningful to that :class:`Mailbox` |
| instance. A key continues to identify a message even if the corresponding |
| message is modified, such as by replacing it with another message. |
| |
| Messages may be added to a :class:`Mailbox` instance using the set-like |
| method :meth:`add` and removed using a ``del`` statement or the set-like |
| methods :meth:`remove` and :meth:`discard`. |
| |
| :class:`Mailbox` interface semantics differ from dictionary semantics in some |
| noteworthy ways. Each time a message is requested, a new representation |
| (typically a :class:`Message` instance) is generated based upon the current |
| state of the mailbox. Similarly, when a message is added to a |
| :class:`Mailbox` instance, the provided message representation's contents are |
| copied. In neither case is a reference to the message representation kept by |
| the :class:`Mailbox` instance. |
| |
| The default :class:`Mailbox` iterator iterates over message representations, |
| not keys as the default dictionary iterator does. Moreover, modification of a |
| mailbox during iteration is safe and well-defined. Messages added to the |
| mailbox after an iterator is created will not be seen by the |
| iterator. Messages removed from the mailbox before the iterator yields them |
| will be silently skipped, though using a key from an iterator may result in a |
| :exc:`KeyError` exception if the corresponding message is subsequently |
| removed. |
| |
| .. warning:: |
| |
| Be very cautious when modifying mailboxes that might be simultaneously |
| changed by some other process. The safest mailbox format to use for such |
| tasks is Maildir; try to avoid using single-file formats such as mbox for |
| concurrent writing. If you're modifying a mailbox, you *must* lock it by |
| calling the :meth:`lock` and :meth:`unlock` methods *before* reading any |
| messages in the file or making any changes by adding or deleting a |
| message. Failing to lock the mailbox runs the risk of losing messages or |
| corrupting the entire mailbox. |
| |
| :class:`Mailbox` instances have the following methods: |
| |
| |
| .. method:: add(message) |
| |
| Add *message* to the mailbox and return the key that has been assigned to |
| it. |
| |
| Parameter *message* may be a :class:`Message` instance, an |
| :class:`email.Message.Message` instance, a string, a byte string, or a |
| file-like object (which should be open in binary mode). If *message* is |
| an instance of the |
| appropriate format-specific :class:`Message` subclass (e.g., if it's an |
| :class:`mboxMessage` instance and this is an :class:`mbox` instance), its |
| format-specific information is used. Otherwise, reasonable defaults for |
| format-specific information are used. |
| |
| .. versionchanged:: 3.2 support for binary input |
| |
| |
| .. method:: remove(key) |
| __delitem__(key) |
| discard(key) |
| |
| Delete the message corresponding to *key* from the mailbox. |
| |
| If no such message exists, a :exc:`KeyError` exception is raised if the |
| method was called as :meth:`remove` or :meth:`__delitem__` but no |
| exception is raised if the method was called as :meth:`discard`. The |
| behavior of :meth:`discard` may be preferred if the underlying mailbox |
| format supports concurrent modification by other processes. |
| |
| |
| .. method:: __setitem__(key, message) |
| |
| Replace the message corresponding to *key* with *message*. Raise a |
| :exc:`KeyError` exception if no message already corresponds to *key*. |
| |
| As with :meth:`add`, parameter *message* may be a :class:`Message` |
| instance, an :class:`email.Message.Message` instance, a string, a byte |
| string, or a file-like object (which should be open in binary mode). If |
| *message* is an |
| instance of the appropriate format-specific :class:`Message` subclass |
| (e.g., if it's an :class:`mboxMessage` instance and this is an |
| :class:`mbox` instance), its format-specific information is |
| used. Otherwise, the format-specific information of the message that |
| currently corresponds to *key* is left unchanged. |
| |
| |
| .. method:: iterkeys() |
| keys() |
| |
| Return an iterator over all keys if called as :meth:`iterkeys` or return a |
| list of keys if called as :meth:`keys`. |
| |
| |
| .. method:: itervalues() |
| __iter__() |
| values() |
| |
| Return an iterator over representations of all messages if called as |
| :meth:`itervalues` or :meth:`__iter__` or return a list of such |
| representations if called as :meth:`values`. The messages are represented |
| as instances of the appropriate format-specific :class:`Message` subclass |
| unless a custom message factory was specified when the :class:`Mailbox` |
| instance was initialized. |
| |
| .. note:: |
| |
| The behavior of :meth:`__iter__` is unlike that of dictionaries, which |
| iterate over keys. |
| |
| |
| .. method:: iteritems() |
| items() |
| |
| Return an iterator over (*key*, *message*) pairs, where *key* is a key and |
| *message* is a message representation, if called as :meth:`iteritems` or |
| return a list of such pairs if called as :meth:`items`. The messages are |
| represented as instances of the appropriate format-specific |
| :class:`Message` subclass unless a custom message factory was specified |
| when the :class:`Mailbox` instance was initialized. |
| |
| |
| .. method:: get(key, default=None) |
| __getitem__(key) |
| |
| Return a representation of the message corresponding to *key*. If no such |
| message exists, *default* is returned if the method was called as |
| :meth:`get` and a :exc:`KeyError` exception is raised if the method was |
| called as :meth:`__getitem__`. The message is represented as an instance |
| of the appropriate format-specific :class:`Message` subclass unless a |
| custom message factory was specified when the :class:`Mailbox` instance |
| was initialized. |
| |
| |
| .. method:: get_message(key) |
| |
| Return a representation of the message corresponding to *key* as an |
| instance of the appropriate format-specific :class:`Message` subclass, or |
| raise a :exc:`KeyError` exception if no such message exists. |
| |
| |
| .. method:: get_bytes(key) |
| |
| Return a byte representation of the message corresponding to *key*, or |
| raise a :exc:`KeyError` exception if no such message exists. |
| |
| .. versionadded:: 3.2 |
| |
| |
| .. method:: get_string(key) |
| |
| Return a string representation of the message corresponding to *key*, or |
| raise a :exc:`KeyError` exception if no such message exists. The |
| message is processed through :class:`email.message.Message` to |
| convert it to a 7bit clean representation. |
| |
| |
| .. method:: get_file(key) |
| |
| Return a file-like representation of the message corresponding to *key*, |
| or raise a :exc:`KeyError` exception if no such message exists. The |
| file-like object behaves as if open in binary mode. This file should be |
| closed once it is no longer needed. |
| |
| .. versionchanged:: 3.2 |
| The file object really is a binary file; previously it was incorrectly |
| returned in text mode. Also, the file-like object now supports the |
| context manager protocol: you can use a :keyword:`with` statement to |
| automatically close it. |
| |
| .. note:: |
| |
| Unlike other representations of messages, file-like representations are |
| not necessarily independent of the :class:`Mailbox` instance that |
| created them or of the underlying mailbox. More specific documentation |
| is provided by each subclass. |
| |
| |
| .. method:: __contains__(key) |
| |
| Return ``True`` if *key* corresponds to a message, ``False`` otherwise. |
| |
| |
| .. method:: __len__() |
| |
| Return a count of messages in the mailbox. |
| |
| |
| .. method:: clear() |
| |
| Delete all messages from the mailbox. |
| |
| |
| .. method:: pop(key, default=None) |
| |
| Return a representation of the message corresponding to *key* and delete |
| the message. If no such message exists, return *default*. The message is |
| represented as an instance of the appropriate format-specific |
| :class:`Message` subclass unless a custom message factory was specified |
| when the :class:`Mailbox` instance was initialized. |
| |
| |
| .. method:: popitem() |
| |
| Return an arbitrary (*key*, *message*) pair, where *key* is a key and |
| *message* is a message representation, and delete the corresponding |
| message. If the mailbox is empty, raise a :exc:`KeyError` exception. The |
| message is represented as an instance of the appropriate format-specific |
| :class:`Message` subclass unless a custom message factory was specified |
| when the :class:`Mailbox` instance was initialized. |
| |
| |
| .. method:: update(arg) |
| |
| Parameter *arg* should be a *key*-to-*message* mapping or an iterable of |
| (*key*, *message*) pairs. Updates the mailbox so that, for each given |
| *key* and *message*, the message corresponding to *key* is set to |
| *message* as if by using :meth:`__setitem__`. As with :meth:`__setitem__`, |
| each *key* must already correspond to a message in the mailbox or else a |
| :exc:`KeyError` exception will be raised, so in general it is incorrect |
| for *arg* to be a :class:`Mailbox` instance. |
| |
| .. note:: |
| |
| Unlike with dictionaries, keyword arguments are not supported. |
| |
| |
| .. method:: flush() |
| |
| Write any pending changes to the filesystem. For some :class:`Mailbox` |
| subclasses, changes are always written immediately and :meth:`flush` does |
| nothing, but you should still make a habit of calling this method. |
| |
| |
| .. method:: lock() |
| |
| Acquire an exclusive advisory lock on the mailbox so that other processes |
| know not to modify it. An :exc:`ExternalClashError` is raised if the lock |
| is not available. The particular locking mechanisms used depend upon the |
| mailbox format. You should *always* lock the mailbox before making any |
| modifications to its contents. |
| |
| |
| .. method:: unlock() |
| |
| Release the lock on the mailbox, if any. |
| |
| |
| .. method:: close() |
| |
| Flush the mailbox, unlock it if necessary, and close any open files. For |
| some :class:`Mailbox` subclasses, this method does nothing. |
| |
| |
| .. _mailbox-maildir: |
| |
| :class:`Maildir` |
| ^^^^^^^^^^^^^^^^ |
| |
| |
| .. class:: Maildir(dirname, factory=None, create=True) |
| |
| A subclass of :class:`Mailbox` for mailboxes in Maildir format. Parameter |
| *factory* is a callable object that accepts a file-like message representation |
| (which behaves as if opened in binary mode) and returns a custom representation. |
| If *factory* is ``None``, :class:`MaildirMessage` is used as the default message |
| representation. If *create* is ``True``, the mailbox is created if it does not |
| exist. |
| |
| It is for historical reasons that *dirname* is named as such rather than *path*. |
| |
| Maildir is a directory-based mailbox format invented for the qmail mail |
| transfer agent and now widely supported by other programs. Messages in a |
| Maildir mailbox are stored in separate files within a common directory |
| structure. This design allows Maildir mailboxes to be accessed and modified |
| by multiple unrelated programs without data corruption, so file locking is |
| unnecessary. |
| |
| Maildir mailboxes contain three subdirectories, namely: :file:`tmp`, |
| :file:`new`, and :file:`cur`. Messages are created momentarily in the |
| :file:`tmp` subdirectory and then moved to the :file:`new` subdirectory to |
| finalize delivery. A mail user agent may subsequently move the message to the |
| :file:`cur` subdirectory and store information about the state of the message |
| in a special "info" section appended to its file name. |
| |
| Folders of the style introduced by the Courier mail transfer agent are also |
| supported. Any subdirectory of the main mailbox is considered a folder if |
| ``'.'`` is the first character in its name. Folder names are represented by |
| :class:`Maildir` without the leading ``'.'``. Each folder is itself a Maildir |
| mailbox but should not contain other folders. Instead, a logical nesting is |
| indicated using ``'.'`` to delimit levels, e.g., "Archived.2005.07". |
| |
| .. note:: |
| |
| The Maildir specification requires the use of a colon (``':'``) in certain |
| message file names. However, some operating systems do not permit this |
| character in file names, If you wish to use a Maildir-like format on such |
| an operating system, you should specify another character to use |
| instead. The exclamation point (``'!'``) is a popular choice. For |
| example:: |
| |
| import mailbox |
| mailbox.Maildir.colon = '!' |
| |
| The :attr:`colon` attribute may also be set on a per-instance basis. |
| |
| :class:`Maildir` instances have all of the methods of :class:`Mailbox` in |
| addition to the following: |
| |
| |
| .. method:: list_folders() |
| |
| Return a list of the names of all folders. |
| |
| |
| .. method:: get_folder(folder) |
| |
| Return a :class:`Maildir` instance representing the folder whose name is |
| *folder*. A :exc:`NoSuchMailboxError` exception is raised if the folder |
| does not exist. |
| |
| |
| .. method:: add_folder(folder) |
| |
| Create a folder whose name is *folder* and return a :class:`Maildir` |
| instance representing it. |
| |
| |
| .. method:: remove_folder(folder) |
| |
| Delete the folder whose name is *folder*. If the folder contains any |
| messages, a :exc:`NotEmptyError` exception will be raised and the folder |
| will not be deleted. |
| |
| |
| .. method:: clean() |
| |
| Delete temporary files from the mailbox that have not been accessed in the |
| last 36 hours. The Maildir specification says that mail-reading programs |
| should do this occasionally. |
| |
| Some :class:`Mailbox` methods implemented by :class:`Maildir` deserve special |
| remarks: |
| |
| |
| .. method:: add(message) |
| __setitem__(key, message) |
| update(arg) |
| |
| .. warning:: |
| |
| These methods generate unique file names based upon the current process |
| ID. When using multiple threads, undetected name clashes may occur and |
| cause corruption of the mailbox unless threads are coordinated to avoid |
| using these methods to manipulate the same mailbox simultaneously. |
| |
| |
| .. method:: flush() |
| |
| All changes to Maildir mailboxes are immediately applied, so this method |
| does nothing. |
| |
| |
| .. method:: lock() |
| unlock() |
| |
| Maildir mailboxes do not support (or require) locking, so these methods do |
| nothing. |
| |
| |
| .. method:: close() |
| |
| :class:`Maildir` instances do not keep any open files and the underlying |
| mailboxes do not support locking, so this method does nothing. |
| |
| |
| .. method:: get_file(key) |
| |
| Depending upon the host platform, it may not be possible to modify or |
| remove the underlying message while the returned file remains open. |
| |
| |
| .. seealso:: |
| |
| `maildir man page from qmail <http://www.qmail.org/man/man5/maildir.html>`_ |
| The original specification of the format. |
| |
| `Using maildir format <http://cr.yp.to/proto/maildir.html>`_ |
| Notes on Maildir by its inventor. Includes an updated name-creation scheme and |
| details on "info" semantics. |
| |
| `maildir man page from Courier <http://www.courier-mta.org/maildir.html>`_ |
| Another specification of the format. Describes a common extension for supporting |
| folders. |
| |
| |
| .. _mailbox-mbox: |
| |
| :class:`mbox` |
| ^^^^^^^^^^^^^ |
| |
| |
| .. class:: mbox(path, factory=None, create=True) |
| |
| A subclass of :class:`Mailbox` for mailboxes in mbox format. Parameter *factory* |
| is a callable object that accepts a file-like message representation (which |
| behaves as if opened in binary mode) and returns a custom representation. If |
| *factory* is ``None``, :class:`mboxMessage` is used as the default message |
| representation. If *create* is ``True``, the mailbox is created if it does not |
| exist. |
| |
| The mbox format is the classic format for storing mail on Unix systems. All |
| messages in an mbox mailbox are stored in a single file with the beginning of |
| each message indicated by a line whose first five characters are "From ". |
| |
| Several variations of the mbox format exist to address perceived shortcomings in |
| the original. In the interest of compatibility, :class:`mbox` implements the |
| original format, which is sometimes referred to as :dfn:`mboxo`. This means that |
| the :mailheader:`Content-Length` header, if present, is ignored and that any |
| occurrences of "From " at the beginning of a line in a message body are |
| transformed to ">From " when storing the message, although occurrences of ">From |
| " are not transformed to "From " when reading the message. |
| |
| Some :class:`Mailbox` methods implemented by :class:`mbox` deserve special |
| remarks: |
| |
| |
| .. method:: get_file(key) |
| |
| Using the file after calling :meth:`flush` or :meth:`close` on the |
| :class:`mbox` instance may yield unpredictable results or raise an |
| exception. |
| |
| |
| .. method:: lock() |
| unlock() |
| |
| Three locking mechanisms are used---dot locking and, if available, the |
| :c:func:`flock` and :c:func:`lockf` system calls. |
| |
| |
| .. seealso:: |
| |
| `mbox man page from qmail <http://www.qmail.org/man/man5/mbox.html>`_ |
| A specification of the format and its variations. |
| |
| `mbox man page from tin <http://www.tin.org/bin/man.cgi?section=5&topic=mbox>`_ |
| Another specification of the format, with details on locking. |
| |
| `Configuring Netscape Mail on Unix: Why The Content-Length Format is Bad <http://www.jwz.org/doc/content-length.html>`_ |
| An argument for using the original mbox format rather than a variation. |
| |
| `"mbox" is a family of several mutually incompatible mailbox formats <http://homepages.tesco.net./~J.deBoynePollard/FGA/mail-mbox-formats.html>`_ |
| A history of mbox variations. |
| |
| |
| .. _mailbox-mh: |
| |
| :class:`MH` |
| ^^^^^^^^^^^ |
| |
| |
| .. class:: MH(path, factory=None, create=True) |
| |
| A subclass of :class:`Mailbox` for mailboxes in MH format. Parameter *factory* |
| is a callable object that accepts a file-like message representation (which |
| behaves as if opened in binary mode) and returns a custom representation. If |
| *factory* is ``None``, :class:`MHMessage` is used as the default message |
| representation. If *create* is ``True``, the mailbox is created if it does not |
| exist. |
| |
| MH is a directory-based mailbox format invented for the MH Message Handling |
| System, a mail user agent. Each message in an MH mailbox resides in its own |
| file. An MH mailbox may contain other MH mailboxes (called :dfn:`folders`) in |
| addition to messages. Folders may be nested indefinitely. MH mailboxes also |
| support :dfn:`sequences`, which are named lists used to logically group |
| messages without moving them to sub-folders. Sequences are defined in a file |
| called :file:`.mh_sequences` in each folder. |
| |
| The :class:`MH` class manipulates MH mailboxes, but it does not attempt to |
| emulate all of :program:`mh`'s behaviors. In particular, it does not modify |
| and is not affected by the :file:`context` or :file:`.mh_profile` files that |
| are used by :program:`mh` to store its state and configuration. |
| |
| :class:`MH` instances have all of the methods of :class:`Mailbox` in addition |
| to the following: |
| |
| |
| .. method:: list_folders() |
| |
| Return a list of the names of all folders. |
| |
| |
| .. method:: get_folder(folder) |
| |
| Return an :class:`MH` instance representing the folder whose name is |
| *folder*. A :exc:`NoSuchMailboxError` exception is raised if the folder |
| does not exist. |
| |
| |
| .. method:: add_folder(folder) |
| |
| Create a folder whose name is *folder* and return an :class:`MH` instance |
| representing it. |
| |
| |
| .. method:: remove_folder(folder) |
| |
| Delete the folder whose name is *folder*. If the folder contains any |
| messages, a :exc:`NotEmptyError` exception will be raised and the folder |
| will not be deleted. |
| |
| |
| .. method:: get_sequences() |
| |
| Return a dictionary of sequence names mapped to key lists. If there are no |
| sequences, the empty dictionary is returned. |
| |
| |
| .. method:: set_sequences(sequences) |
| |
| Re-define the sequences that exist in the mailbox based upon *sequences*, |
| a dictionary of names mapped to key lists, like returned by |
| :meth:`get_sequences`. |
| |
| |
| .. method:: pack() |
| |
| Rename messages in the mailbox as necessary to eliminate gaps in |
| numbering. Entries in the sequences list are updated correspondingly. |
| |
| .. note:: |
| |
| Already-issued keys are invalidated by this operation and should not be |
| subsequently used. |
| |
| Some :class:`Mailbox` methods implemented by :class:`MH` deserve special |
| remarks: |
| |
| |
| .. method:: remove(key) |
| __delitem__(key) |
| discard(key) |
| |
| These methods immediately delete the message. The MH convention of marking |
| a message for deletion by prepending a comma to its name is not used. |
| |
| |
| .. method:: lock() |
| unlock() |
| |
| Three locking mechanisms are used---dot locking and, if available, the |
| :c:func:`flock` and :c:func:`lockf` system calls. For MH mailboxes, locking |
| the mailbox means locking the :file:`.mh_sequences` file and, only for the |
| duration of any operations that affect them, locking individual message |
| files. |
| |
| |
| .. method:: get_file(key) |
| |
| Depending upon the host platform, it may not be possible to remove the |
| underlying message while the returned file remains open. |
| |
| |
| .. method:: flush() |
| |
| All changes to MH mailboxes are immediately applied, so this method does |
| nothing. |
| |
| |
| .. method:: close() |
| |
| :class:`MH` instances do not keep any open files, so this method is |
| equivalent to :meth:`unlock`. |
| |
| |
| .. seealso:: |
| |
| `nmh - Message Handling System <http://www.nongnu.org/nmh/>`_ |
| Home page of :program:`nmh`, an updated version of the original :program:`mh`. |
| |
| `MH & nmh: Email for Users & Programmers <http://rand-mh.sourceforge.net/book/>`_ |
| A GPL-licensed book on :program:`mh` and :program:`nmh`, with some information |
| on the mailbox format. |
| |
| |
| .. _mailbox-babyl: |
| |
| :class:`Babyl` |
| ^^^^^^^^^^^^^^ |
| |
| |
| .. class:: Babyl(path, factory=None, create=True) |
| |
| A subclass of :class:`Mailbox` for mailboxes in Babyl format. Parameter |
| *factory* is a callable object that accepts a file-like message representation |
| (which behaves as if opened in binary mode) and returns a custom representation. |
| If *factory* is ``None``, :class:`BabylMessage` is used as the default message |
| representation. If *create* is ``True``, the mailbox is created if it does not |
| exist. |
| |
| Babyl is a single-file mailbox format used by the Rmail mail user agent |
| included with Emacs. The beginning of a message is indicated by a line |
| containing the two characters Control-Underscore (``'\037'``) and Control-L |
| (``'\014'``). The end of a message is indicated by the start of the next |
| message or, in the case of the last message, a line containing a |
| Control-Underscore (``'\037'``) character. |
| |
| Messages in a Babyl mailbox have two sets of headers, original headers and |
| so-called visible headers. Visible headers are typically a subset of the |
| original headers that have been reformatted or abridged to be more |
| attractive. Each message in a Babyl mailbox also has an accompanying list of |
| :dfn:`labels`, or short strings that record extra information about the |
| message, and a list of all user-defined labels found in the mailbox is kept |
| in the Babyl options section. |
| |
| :class:`Babyl` instances have all of the methods of :class:`Mailbox` in |
| addition to the following: |
| |
| |
| .. method:: get_labels() |
| |
| Return a list of the names of all user-defined labels used in the mailbox. |
| |
| .. note:: |
| |
| The actual messages are inspected to determine which labels exist in |
| the mailbox rather than consulting the list of labels in the Babyl |
| options section, but the Babyl section is updated whenever the mailbox |
| is modified. |
| |
| Some :class:`Mailbox` methods implemented by :class:`Babyl` deserve special |
| remarks: |
| |
| |
| .. method:: get_file(key) |
| |
| In Babyl mailboxes, the headers of a message are not stored contiguously |
| with the body of the message. To generate a file-like representation, the |
| headers and body are copied together into a :class:`StringIO` instance |
| (from the :mod:`StringIO` module), which has an API identical to that of a |
| file. As a result, the file-like object is truly independent of the |
| underlying mailbox but does not save memory compared to a string |
| representation. |
| |
| |
| .. method:: lock() |
| unlock() |
| |
| Three locking mechanisms are used---dot locking and, if available, the |
| :c:func:`flock` and :c:func:`lockf` system calls. |
| |
| |
| .. seealso:: |
| |
| `Format of Version 5 Babyl Files <http://quimby.gnus.org/notes/BABYL>`_ |
| A specification of the Babyl format. |
| |
| `Reading Mail with Rmail <http://www.gnu.org/software/emacs/manual/html_node/emacs/Rmail.html>`_ |
| The Rmail manual, with some information on Babyl semantics. |
| |
| |
| .. _mailbox-mmdf: |
| |
| :class:`MMDF` |
| ^^^^^^^^^^^^^ |
| |
| |
| .. class:: MMDF(path, factory=None, create=True) |
| |
| A subclass of :class:`Mailbox` for mailboxes in MMDF format. Parameter *factory* |
| is a callable object that accepts a file-like message representation (which |
| behaves as if opened in binary mode) and returns a custom representation. If |
| *factory* is ``None``, :class:`MMDFMessage` is used as the default message |
| representation. If *create* is ``True``, the mailbox is created if it does not |
| exist. |
| |
| MMDF is a single-file mailbox format invented for the Multichannel Memorandum |
| Distribution Facility, a mail transfer agent. Each message is in the same |
| form as an mbox message but is bracketed before and after by lines containing |
| four Control-A (``'\001'``) characters. As with the mbox format, the |
| beginning of each message is indicated by a line whose first five characters |
| are "From ", but additional occurrences of "From " are not transformed to |
| ">From " when storing messages because the extra message separator lines |
| prevent mistaking such occurrences for the starts of subsequent messages. |
| |
| Some :class:`Mailbox` methods implemented by :class:`MMDF` deserve special |
| remarks: |
| |
| |
| .. method:: get_file(key) |
| |
| Using the file after calling :meth:`flush` or :meth:`close` on the |
| :class:`MMDF` instance may yield unpredictable results or raise an |
| exception. |
| |
| |
| .. method:: lock() |
| unlock() |
| |
| Three locking mechanisms are used---dot locking and, if available, the |
| :c:func:`flock` and :c:func:`lockf` system calls. |
| |
| |
| .. seealso:: |
| |
| `mmdf man page from tin <http://www.tin.org/bin/man.cgi?section=5&topic=mmdf>`_ |
| A specification of MMDF format from the documentation of tin, a newsreader. |
| |
| `MMDF <http://en.wikipedia.org/wiki/MMDF>`_ |
| A Wikipedia article describing the Multichannel Memorandum Distribution |
| Facility. |
| |
| |
| .. _mailbox-message-objects: |
| |
| :class:`Message` objects |
| ------------------------ |
| |
| |
| .. class:: Message(message=None) |
| |
| A subclass of the :mod:`email.Message` module's :class:`Message`. Subclasses of |
| :class:`mailbox.Message` add mailbox-format-specific state and behavior. |
| |
| If *message* is omitted, the new instance is created in a default, empty state. |
| If *message* is an :class:`email.Message.Message` instance, its contents are |
| copied; furthermore, any format-specific information is converted insofar as |
| possible if *message* is a :class:`Message` instance. If *message* is a string, |
| a byte string, |
| or a file, it should contain an :rfc:`2822`\ -compliant message, which is read |
| and parsed. Files should be open in binary mode, but text mode files |
| are accepted for backward compatibility. |
| |
| The format-specific state and behaviors offered by subclasses vary, but in |
| general it is only the properties that are not specific to a particular |
| mailbox that are supported (although presumably the properties are specific |
| to a particular mailbox format). For example, file offsets for single-file |
| mailbox formats and file names for directory-based mailbox formats are not |
| retained, because they are only applicable to the original mailbox. But state |
| such as whether a message has been read by the user or marked as important is |
| retained, because it applies to the message itself. |
| |
| There is no requirement that :class:`Message` instances be used to represent |
| messages retrieved using :class:`Mailbox` instances. In some situations, the |
| time and memory required to generate :class:`Message` representations might |
| not not acceptable. For such situations, :class:`Mailbox` instances also |
| offer string and file-like representations, and a custom message factory may |
| be specified when a :class:`Mailbox` instance is initialized. |
| |
| |
| .. _mailbox-maildirmessage: |
| |
| :class:`MaildirMessage` |
| ^^^^^^^^^^^^^^^^^^^^^^^ |
| |
| |
| .. class:: MaildirMessage(message=None) |
| |
| A message with Maildir-specific behaviors. Parameter *message* has the same |
| meaning as with the :class:`Message` constructor. |
| |
| Typically, a mail user agent application moves all of the messages in the |
| :file:`new` subdirectory to the :file:`cur` subdirectory after the first time |
| the user opens and closes the mailbox, recording that the messages are old |
| whether or not they've actually been read. Each message in :file:`cur` has an |
| "info" section added to its file name to store information about its state. |
| (Some mail readers may also add an "info" section to messages in |
| :file:`new`.) The "info" section may take one of two forms: it may contain |
| "2," followed by a list of standardized flags (e.g., "2,FR") or it may |
| contain "1," followed by so-called experimental information. Standard flags |
| for Maildir messages are as follows: |
| |
| +------+---------+--------------------------------+ |
| | Flag | Meaning | Explanation | |
| +======+=========+================================+ |
| | D | Draft | Under composition | |
| +------+---------+--------------------------------+ |
| | F | Flagged | Marked as important | |
| +------+---------+--------------------------------+ |
| | P | Passed | Forwarded, resent, or bounced | |
| +------+---------+--------------------------------+ |
| | R | Replied | Replied to | |
| +------+---------+--------------------------------+ |
| | S | Seen | Read | |
| +------+---------+--------------------------------+ |
| | T | Trashed | Marked for subsequent deletion | |
| +------+---------+--------------------------------+ |
| |
| :class:`MaildirMessage` instances offer the following methods: |
| |
| |
| .. method:: get_subdir() |
| |
| Return either "new" (if the message should be stored in the :file:`new` |
| subdirectory) or "cur" (if the message should be stored in the :file:`cur` |
| subdirectory). |
| |
| .. note:: |
| |
| A message is typically moved from :file:`new` to :file:`cur` after its |
| mailbox has been accessed, whether or not the message is has been |
| read. A message ``msg`` has been read if ``"S" in msg.get_flags()`` is |
| ``True``. |
| |
| |
| .. method:: set_subdir(subdir) |
| |
| Set the subdirectory the message should be stored in. Parameter *subdir* |
| must be either "new" or "cur". |
| |
| |
| .. method:: get_flags() |
| |
| Return a string specifying the flags that are currently set. If the |
| message complies with the standard Maildir format, the result is the |
| concatenation in alphabetical order of zero or one occurrence of each of |
| ``'D'``, ``'F'``, ``'P'``, ``'R'``, ``'S'``, and ``'T'``. The empty string |
| is returned if no flags are set or if "info" contains experimental |
| semantics. |
| |
| |
| .. method:: set_flags(flags) |
| |
| Set the flags specified by *flags* and unset all others. |
| |
| |
| .. method:: add_flag(flag) |
| |
| Set the flag(s) specified by *flag* without changing other flags. To add |
| more than one flag at a time, *flag* may be a string of more than one |
| character. The current "info" is overwritten whether or not it contains |
| experimental information rather than flags. |
| |
| |
| .. method:: remove_flag(flag) |
| |
| Unset the flag(s) specified by *flag* without changing other flags. To |
| remove more than one flag at a time, *flag* maybe a string of more than |
| one character. If "info" contains experimental information rather than |
| flags, the current "info" is not modified. |
| |
| |
| .. method:: get_date() |
| |
| Return the delivery date of the message as a floating-point number |
| representing seconds since the epoch. |
| |
| |
| .. method:: set_date(date) |
| |
| Set the delivery date of the message to *date*, a floating-point number |
| representing seconds since the epoch. |
| |
| |
| .. method:: get_info() |
| |
| Return a string containing the "info" for a message. This is useful for |
| accessing and modifying "info" that is experimental (i.e., not a list of |
| flags). |
| |
| |
| .. method:: set_info(info) |
| |
| Set "info" to *info*, which should be a string. |
| |
| When a :class:`MaildirMessage` instance is created based upon an |
| :class:`mboxMessage` or :class:`MMDFMessage` instance, the :mailheader:`Status` |
| and :mailheader:`X-Status` headers are omitted and the following conversions |
| take place: |
| |
| +--------------------+----------------------------------------------+ |
| | Resulting state | :class:`mboxMessage` or :class:`MMDFMessage` | |
| | | state | |
| +====================+==============================================+ |
| | "cur" subdirectory | O flag | |
| +--------------------+----------------------------------------------+ |
| | F flag | F flag | |
| +--------------------+----------------------------------------------+ |
| | R flag | A flag | |
| +--------------------+----------------------------------------------+ |
| | S flag | R flag | |
| +--------------------+----------------------------------------------+ |
| | T flag | D flag | |
| +--------------------+----------------------------------------------+ |
| |
| When a :class:`MaildirMessage` instance is created based upon an |
| :class:`MHMessage` instance, the following conversions take place: |
| |
| +-------------------------------+--------------------------+ |
| | Resulting state | :class:`MHMessage` state | |
| +===============================+==========================+ |
| | "cur" subdirectory | "unseen" sequence | |
| +-------------------------------+--------------------------+ |
| | "cur" subdirectory and S flag | no "unseen" sequence | |
| +-------------------------------+--------------------------+ |
| | F flag | "flagged" sequence | |
| +-------------------------------+--------------------------+ |
| | R flag | "replied" sequence | |
| +-------------------------------+--------------------------+ |
| |
| When a :class:`MaildirMessage` instance is created based upon a |
| :class:`BabylMessage` instance, the following conversions take place: |
| |
| +-------------------------------+-------------------------------+ |
| | Resulting state | :class:`BabylMessage` state | |
| +===============================+===============================+ |
| | "cur" subdirectory | "unseen" label | |
| +-------------------------------+-------------------------------+ |
| | "cur" subdirectory and S flag | no "unseen" label | |
| +-------------------------------+-------------------------------+ |
| | P flag | "forwarded" or "resent" label | |
| +-------------------------------+-------------------------------+ |
| | R flag | "answered" label | |
| +-------------------------------+-------------------------------+ |
| | T flag | "deleted" label | |
| +-------------------------------+-------------------------------+ |
| |
| |
| .. _mailbox-mboxmessage: |
| |
| :class:`mboxMessage` |
| ^^^^^^^^^^^^^^^^^^^^ |
| |
| |
| .. class:: mboxMessage(message=None) |
| |
| A message with mbox-specific behaviors. Parameter *message* has the same meaning |
| as with the :class:`Message` constructor. |
| |
| Messages in an mbox mailbox are stored together in a single file. The |
| sender's envelope address and the time of delivery are typically stored in a |
| line beginning with "From " that is used to indicate the start of a message, |
| though there is considerable variation in the exact format of this data among |
| mbox implementations. Flags that indicate the state of the message, such as |
| whether it has been read or marked as important, are typically stored in |
| :mailheader:`Status` and :mailheader:`X-Status` headers. |
| |
| Conventional flags for mbox messages are as follows: |
| |
| +------+----------+--------------------------------+ |
| | Flag | Meaning | Explanation | |
| +======+==========+================================+ |
| | R | Read | Read | |
| +------+----------+--------------------------------+ |
| | O | Old | Previously detected by MUA | |
| +------+----------+--------------------------------+ |
| | D | Deleted | Marked for subsequent deletion | |
| +------+----------+--------------------------------+ |
| | F | Flagged | Marked as important | |
| +------+----------+--------------------------------+ |
| | A | Answered | Replied to | |
| +------+----------+--------------------------------+ |
| |
| The "R" and "O" flags are stored in the :mailheader:`Status` header, and the |
| "D", "F", and "A" flags are stored in the :mailheader:`X-Status` header. The |
| flags and headers typically appear in the order mentioned. |
| |
| :class:`mboxMessage` instances offer the following methods: |
| |
| |
| .. method:: get_from() |
| |
| Return a string representing the "From " line that marks the start of the |
| message in an mbox mailbox. The leading "From " and the trailing newline |
| are excluded. |
| |
| |
| .. method:: set_from(from_, time_=None) |
| |
| Set the "From " line to *from_*, which should be specified without a |
| leading "From " or trailing newline. For convenience, *time_* may be |
| specified and will be formatted appropriately and appended to *from_*. If |
| *time_* is specified, it should be a :class:`struct_time` instance, a |
| tuple suitable for passing to :meth:`time.strftime`, or ``True`` (to use |
| :meth:`time.gmtime`). |
| |
| |
| .. method:: get_flags() |
| |
| Return a string specifying the flags that are currently set. If the |
| message complies with the conventional format, the result is the |
| concatenation in the following order of zero or one occurrence of each of |
| ``'R'``, ``'O'``, ``'D'``, ``'F'``, and ``'A'``. |
| |
| |
| .. method:: set_flags(flags) |
| |
| Set the flags specified by *flags* and unset all others. Parameter *flags* |
| should be the concatenation in any order of zero or more occurrences of |
| each of ``'R'``, ``'O'``, ``'D'``, ``'F'``, and ``'A'``. |
| |
| |
| .. method:: add_flag(flag) |
| |
| Set the flag(s) specified by *flag* without changing other flags. To add |
| more than one flag at a time, *flag* may be a string of more than one |
| character. |
| |
| |
| .. method:: remove_flag(flag) |
| |
| Unset the flag(s) specified by *flag* without changing other flags. To |
| remove more than one flag at a time, *flag* maybe a string of more than |
| one character. |
| |
| When an :class:`mboxMessage` instance is created based upon a |
| :class:`MaildirMessage` instance, a "From " line is generated based upon the |
| :class:`MaildirMessage` instance's delivery date, and the following conversions |
| take place: |
| |
| +-----------------+-------------------------------+ |
| | Resulting state | :class:`MaildirMessage` state | |
| +=================+===============================+ |
| | R flag | S flag | |
| +-----------------+-------------------------------+ |
| | O flag | "cur" subdirectory | |
| +-----------------+-------------------------------+ |
| | D flag | T flag | |
| +-----------------+-------------------------------+ |
| | F flag | F flag | |
| +-----------------+-------------------------------+ |
| | A flag | R flag | |
| +-----------------+-------------------------------+ |
| |
| When an :class:`mboxMessage` instance is created based upon an |
| :class:`MHMessage` instance, the following conversions take place: |
| |
| +-------------------+--------------------------+ |
| | Resulting state | :class:`MHMessage` state | |
| +===================+==========================+ |
| | R flag and O flag | no "unseen" sequence | |
| +-------------------+--------------------------+ |
| | O flag | "unseen" sequence | |
| +-------------------+--------------------------+ |
| | F flag | "flagged" sequence | |
| +-------------------+--------------------------+ |
| | A flag | "replied" sequence | |
| +-------------------+--------------------------+ |
| |
| When an :class:`mboxMessage` instance is created based upon a |
| :class:`BabylMessage` instance, the following conversions take place: |
| |
| +-------------------+-----------------------------+ |
| | Resulting state | :class:`BabylMessage` state | |
| +===================+=============================+ |
| | R flag and O flag | no "unseen" label | |
| +-------------------+-----------------------------+ |
| | O flag | "unseen" label | |
| +-------------------+-----------------------------+ |
| | D flag | "deleted" label | |
| +-------------------+-----------------------------+ |
| | A flag | "answered" label | |
| +-------------------+-----------------------------+ |
| |
| When a :class:`Message` instance is created based upon an :class:`MMDFMessage` |
| instance, the "From " line is copied and all flags directly correspond: |
| |
| +-----------------+----------------------------+ |
| | Resulting state | :class:`MMDFMessage` state | |
| +=================+============================+ |
| | R flag | R flag | |
| +-----------------+----------------------------+ |
| | O flag | O flag | |
| +-----------------+----------------------------+ |
| | D flag | D flag | |
| +-----------------+----------------------------+ |
| | F flag | F flag | |
| +-----------------+----------------------------+ |
| | A flag | A flag | |
| +-----------------+----------------------------+ |
| |
| |
| .. _mailbox-mhmessage: |
| |
| :class:`MHMessage` |
| ^^^^^^^^^^^^^^^^^^ |
| |
| |
| .. class:: MHMessage(message=None) |
| |
| A message with MH-specific behaviors. Parameter *message* has the same meaning |
| as with the :class:`Message` constructor. |
| |
| MH messages do not support marks or flags in the traditional sense, but they |
| do support sequences, which are logical groupings of arbitrary messages. Some |
| mail reading programs (although not the standard :program:`mh` and |
| :program:`nmh`) use sequences in much the same way flags are used with other |
| formats, as follows: |
| |
| +----------+------------------------------------------+ |
| | Sequence | Explanation | |
| +==========+==========================================+ |
| | unseen | Not read, but previously detected by MUA | |
| +----------+------------------------------------------+ |
| | replied | Replied to | |
| +----------+------------------------------------------+ |
| | flagged | Marked as important | |
| +----------+------------------------------------------+ |
| |
| :class:`MHMessage` instances offer the following methods: |
| |
| |
| .. method:: get_sequences() |
| |
| Return a list of the names of sequences that include this message. |
| |
| |
| .. method:: set_sequences(sequences) |
| |
| Set the list of sequences that include this message. |
| |
| |
| .. method:: add_sequence(sequence) |
| |
| Add *sequence* to the list of sequences that include this message. |
| |
| |
| .. method:: remove_sequence(sequence) |
| |
| Remove *sequence* from the list of sequences that include this message. |
| |
| When an :class:`MHMessage` instance is created based upon a |
| :class:`MaildirMessage` instance, the following conversions take place: |
| |
| +--------------------+-------------------------------+ |
| | Resulting state | :class:`MaildirMessage` state | |
| +====================+===============================+ |
| | "unseen" sequence | no S flag | |
| +--------------------+-------------------------------+ |
| | "replied" sequence | R flag | |
| +--------------------+-------------------------------+ |
| | "flagged" sequence | F flag | |
| +--------------------+-------------------------------+ |
| |
| When an :class:`MHMessage` instance is created based upon an |
| :class:`mboxMessage` or :class:`MMDFMessage` instance, the :mailheader:`Status` |
| and :mailheader:`X-Status` headers are omitted and the following conversions |
| take place: |
| |
| +--------------------+----------------------------------------------+ |
| | Resulting state | :class:`mboxMessage` or :class:`MMDFMessage` | |
| | | state | |
| +====================+==============================================+ |
| | "unseen" sequence | no R flag | |
| +--------------------+----------------------------------------------+ |
| | "replied" sequence | A flag | |
| +--------------------+----------------------------------------------+ |
| | "flagged" sequence | F flag | |
| +--------------------+----------------------------------------------+ |
| |
| When an :class:`MHMessage` instance is created based upon a |
| :class:`BabylMessage` instance, the following conversions take place: |
| |
| +--------------------+-----------------------------+ |
| | Resulting state | :class:`BabylMessage` state | |
| +====================+=============================+ |
| | "unseen" sequence | "unseen" label | |
| +--------------------+-----------------------------+ |
| | "replied" sequence | "answered" label | |
| +--------------------+-----------------------------+ |
| |
| |
| .. _mailbox-babylmessage: |
| |
| :class:`BabylMessage` |
| ^^^^^^^^^^^^^^^^^^^^^ |
| |
| |
| .. class:: BabylMessage(message=None) |
| |
| A message with Babyl-specific behaviors. Parameter *message* has the same |
| meaning as with the :class:`Message` constructor. |
| |
| Certain message labels, called :dfn:`attributes`, are defined by convention |
| to have special meanings. The attributes are as follows: |
| |
| +-----------+------------------------------------------+ |
| | Label | Explanation | |
| +===========+==========================================+ |
| | unseen | Not read, but previously detected by MUA | |
| +-----------+------------------------------------------+ |
| | deleted | Marked for subsequent deletion | |
| +-----------+------------------------------------------+ |
| | filed | Copied to another file or mailbox | |
| +-----------+------------------------------------------+ |
| | answered | Replied to | |
| +-----------+------------------------------------------+ |
| | forwarded | Forwarded | |
| +-----------+------------------------------------------+ |
| | edited | Modified by the user | |
| +-----------+------------------------------------------+ |
| | resent | Resent | |
| +-----------+------------------------------------------+ |
| |
| By default, Rmail displays only visible headers. The :class:`BabylMessage` |
| class, though, uses the original headers because they are more |
| complete. Visible headers may be accessed explicitly if desired. |
| |
| :class:`BabylMessage` instances offer the following methods: |
| |
| |
| .. method:: get_labels() |
| |
| Return a list of labels on the message. |
| |
| |
| .. method:: set_labels(labels) |
| |
| Set the list of labels on the message to *labels*. |
| |
| |
| .. method:: add_label(label) |
| |
| Add *label* to the list of labels on the message. |
| |
| |
| .. method:: remove_label(label) |
| |
| Remove *label* from the list of labels on the message. |
| |
| |
| .. method:: get_visible() |
| |
| Return an :class:`Message` instance whose headers are the message's |
| visible headers and whose body is empty. |
| |
| |
| .. method:: set_visible(visible) |
| |
| Set the message's visible headers to be the same as the headers in |
| *message*. Parameter *visible* should be a :class:`Message` instance, an |
| :class:`email.Message.Message` instance, a string, or a file-like object |
| (which should be open in text mode). |
| |
| |
| .. method:: update_visible() |
| |
| When a :class:`BabylMessage` instance's original headers are modified, the |
| visible headers are not automatically modified to correspond. This method |
| updates the visible headers as follows: each visible header with a |
| corresponding original header is set to the value of the original header, |
| each visible header without a corresponding original header is removed, |
| and any of :mailheader:`Date`, :mailheader:`From`, :mailheader:`Reply-To`, |
| :mailheader:`To`, :mailheader:`CC`, and :mailheader:`Subject` that are |
| present in the original headers but not the visible headers are added to |
| the visible headers. |
| |
| When a :class:`BabylMessage` instance is created based upon a |
| :class:`MaildirMessage` instance, the following conversions take place: |
| |
| +-------------------+-------------------------------+ |
| | Resulting state | :class:`MaildirMessage` state | |
| +===================+===============================+ |
| | "unseen" label | no S flag | |
| +-------------------+-------------------------------+ |
| | "deleted" label | T flag | |
| +-------------------+-------------------------------+ |
| | "answered" label | R flag | |
| +-------------------+-------------------------------+ |
| | "forwarded" label | P flag | |
| +-------------------+-------------------------------+ |
| |
| When a :class:`BabylMessage` instance is created based upon an |
| :class:`mboxMessage` or :class:`MMDFMessage` instance, the :mailheader:`Status` |
| and :mailheader:`X-Status` headers are omitted and the following conversions |
| take place: |
| |
| +------------------+----------------------------------------------+ |
| | Resulting state | :class:`mboxMessage` or :class:`MMDFMessage` | |
| | | state | |
| +==================+==============================================+ |
| | "unseen" label | no R flag | |
| +------------------+----------------------------------------------+ |
| | "deleted" label | D flag | |
| +------------------+----------------------------------------------+ |
| | "answered" label | A flag | |
| +------------------+----------------------------------------------+ |
| |
| When a :class:`BabylMessage` instance is created based upon an |
| :class:`MHMessage` instance, the following conversions take place: |
| |
| +------------------+--------------------------+ |
| | Resulting state | :class:`MHMessage` state | |
| +==================+==========================+ |
| | "unseen" label | "unseen" sequence | |
| +------------------+--------------------------+ |
| | "answered" label | "replied" sequence | |
| +------------------+--------------------------+ |
| |
| |
| .. _mailbox-mmdfmessage: |
| |
| :class:`MMDFMessage` |
| ^^^^^^^^^^^^^^^^^^^^ |
| |
| |
| .. class:: MMDFMessage(message=None) |
| |
| A message with MMDF-specific behaviors. Parameter *message* has the same meaning |
| as with the :class:`Message` constructor. |
| |
| As with message in an mbox mailbox, MMDF messages are stored with the |
| sender's address and the delivery date in an initial line beginning with |
| "From ". Likewise, flags that indicate the state of the message are |
| typically stored in :mailheader:`Status` and :mailheader:`X-Status` headers. |
| |
| Conventional flags for MMDF messages are identical to those of mbox message |
| and are as follows: |
| |
| +------+----------+--------------------------------+ |
| | Flag | Meaning | Explanation | |
| +======+==========+================================+ |
| | R | Read | Read | |
| +------+----------+--------------------------------+ |
| | O | Old | Previously detected by MUA | |
| +------+----------+--------------------------------+ |
| | D | Deleted | Marked for subsequent deletion | |
| +------+----------+--------------------------------+ |
| | F | Flagged | Marked as important | |
| +------+----------+--------------------------------+ |
| | A | Answered | Replied to | |
| +------+----------+--------------------------------+ |
| |
| The "R" and "O" flags are stored in the :mailheader:`Status` header, and the |
| "D", "F", and "A" flags are stored in the :mailheader:`X-Status` header. The |
| flags and headers typically appear in the order mentioned. |
| |
| :class:`MMDFMessage` instances offer the following methods, which are |
| identical to those offered by :class:`mboxMessage`: |
| |
| |
| .. method:: get_from() |
| |
| Return a string representing the "From " line that marks the start of the |
| message in an mbox mailbox. The leading "From " and the trailing newline |
| are excluded. |
| |
| |
| .. method:: set_from(from_, time_=None) |
| |
| Set the "From " line to *from_*, which should be specified without a |
| leading "From " or trailing newline. For convenience, *time_* may be |
| specified and will be formatted appropriately and appended to *from_*. If |
| *time_* is specified, it should be a :class:`struct_time` instance, a |
| tuple suitable for passing to :meth:`time.strftime`, or ``True`` (to use |
| :meth:`time.gmtime`). |
| |
| |
| .. method:: get_flags() |
| |
| Return a string specifying the flags that are currently set. If the |
| message complies with the conventional format, the result is the |
| concatenation in the following order of zero or one occurrence of each of |
| ``'R'``, ``'O'``, ``'D'``, ``'F'``, and ``'A'``. |
| |
| |
| .. method:: set_flags(flags) |
| |
| Set the flags specified by *flags* and unset all others. Parameter *flags* |
| should be the concatenation in any order of zero or more occurrences of |
| each of ``'R'``, ``'O'``, ``'D'``, ``'F'``, and ``'A'``. |
| |
| |
| .. method:: add_flag(flag) |
| |
| Set the flag(s) specified by *flag* without changing other flags. To add |
| more than one flag at a time, *flag* may be a string of more than one |
| character. |
| |
| |
| .. method:: remove_flag(flag) |
| |
| Unset the flag(s) specified by *flag* without changing other flags. To |
| remove more than one flag at a time, *flag* maybe a string of more than |
| one character. |
| |
| When an :class:`MMDFMessage` instance is created based upon a |
| :class:`MaildirMessage` instance, a "From " line is generated based upon the |
| :class:`MaildirMessage` instance's delivery date, and the following conversions |
| take place: |
| |
| +-----------------+-------------------------------+ |
| | Resulting state | :class:`MaildirMessage` state | |
| +=================+===============================+ |
| | R flag | S flag | |
| +-----------------+-------------------------------+ |
| | O flag | "cur" subdirectory | |
| +-----------------+-------------------------------+ |
| | D flag | T flag | |
| +-----------------+-------------------------------+ |
| | F flag | F flag | |
| +-----------------+-------------------------------+ |
| | A flag | R flag | |
| +-----------------+-------------------------------+ |
| |
| When an :class:`MMDFMessage` instance is created based upon an |
| :class:`MHMessage` instance, the following conversions take place: |
| |
| +-------------------+--------------------------+ |
| | Resulting state | :class:`MHMessage` state | |
| +===================+==========================+ |
| | R flag and O flag | no "unseen" sequence | |
| +-------------------+--------------------------+ |
| | O flag | "unseen" sequence | |
| +-------------------+--------------------------+ |
| | F flag | "flagged" sequence | |
| +-------------------+--------------------------+ |
| | A flag | "replied" sequence | |
| +-------------------+--------------------------+ |
| |
| When an :class:`MMDFMessage` instance is created based upon a |
| :class:`BabylMessage` instance, the following conversions take place: |
| |
| +-------------------+-----------------------------+ |
| | Resulting state | :class:`BabylMessage` state | |
| +===================+=============================+ |
| | R flag and O flag | no "unseen" label | |
| +-------------------+-----------------------------+ |
| | O flag | "unseen" label | |
| +-------------------+-----------------------------+ |
| | D flag | "deleted" label | |
| +-------------------+-----------------------------+ |
| | A flag | "answered" label | |
| +-------------------+-----------------------------+ |
| |
| When an :class:`MMDFMessage` instance is created based upon an |
| :class:`mboxMessage` instance, the "From " line is copied and all flags directly |
| correspond: |
| |
| +-----------------+----------------------------+ |
| | Resulting state | :class:`mboxMessage` state | |
| +=================+============================+ |
| | R flag | R flag | |
| +-----------------+----------------------------+ |
| | O flag | O flag | |
| +-----------------+----------------------------+ |
| | D flag | D flag | |
| +-----------------+----------------------------+ |
| | F flag | F flag | |
| +-----------------+----------------------------+ |
| | A flag | A flag | |
| +-----------------+----------------------------+ |
| |
| |
| Exceptions |
| ---------- |
| |
| The following exception classes are defined in the :mod:`mailbox` module: |
| |
| |
| .. exception:: Error() |
| |
| The based class for all other module-specific exceptions. |
| |
| |
| .. exception:: NoSuchMailboxError() |
| |
| Raised when a mailbox is expected but is not found, such as when instantiating a |
| :class:`Mailbox` subclass with a path that does not exist (and with the *create* |
| parameter set to ``False``), or when opening a folder that does not exist. |
| |
| |
| .. exception:: NotEmptyError() |
| |
| Raised when a mailbox is not empty but is expected to be, such as when deleting |
| a folder that contains messages. |
| |
| |
| .. exception:: ExternalClashError() |
| |
| Raised when some mailbox-related condition beyond the control of the program |
| causes it to be unable to proceed, such as when failing to acquire a lock that |
| another program already holds a lock, or when a uniquely-generated file name |
| already exists. |
| |
| |
| .. exception:: FormatError() |
| |
| Raised when the data in a file cannot be parsed, such as when an :class:`MH` |
| instance attempts to read a corrupted :file:`.mh_sequences` file. |
| |
| |
| .. _mailbox-examples: |
| |
| Examples |
| -------- |
| |
| A simple example of printing the subjects of all messages in a mailbox that seem |
| interesting:: |
| |
| import mailbox |
| for message in mailbox.mbox('~/mbox'): |
| subject = message['subject'] # Could possibly be None. |
| if subject and 'python' in subject.lower(): |
| print(subject) |
| |
| To copy all mail from a Babyl mailbox to an MH mailbox, converting all of the |
| format-specific information that can be converted:: |
| |
| import mailbox |
| destination = mailbox.MH('~/Mail') |
| destination.lock() |
| for message in mailbox.Babyl('~/RMAIL'): |
| destination.add(mailbox.MHMessage(message)) |
| destination.flush() |
| destination.unlock() |
| |
| This example sorts mail from several mailing lists into different mailboxes, |
| being careful to avoid mail corruption due to concurrent modification by other |
| programs, mail loss due to interruption of the program, or premature termination |
| due to malformed messages in the mailbox:: |
| |
| import mailbox |
| import email.Errors |
| |
| list_names = ('python-list', 'python-dev', 'python-bugs') |
| |
| boxes = {name: mailbox.mbox('~/email/%s' % name) for name in list_names} |
| inbox = mailbox.Maildir('~/Maildir', factory=None) |
| |
| for key in inbox.iterkeys(): |
| try: |
| message = inbox[key] |
| except email.Errors.MessageParseError: |
| continue # The message is malformed. Just leave it. |
| |
| for name in list_names: |
| list_id = message['list-id'] |
| if list_id and name in list_id: |
| # Get mailbox to use |
| box = boxes[name] |
| |
| # Write copy to disk before removing original. |
| # If there's a crash, you might duplicate a message, but |
| # that's better than losing a message completely. |
| box.lock() |
| box.add(message) |
| box.flush() |
| box.unlock() |
| |
| # Remove original message |
| inbox.lock() |
| inbox.discard(key) |
| inbox.flush() |
| inbox.unlock() |
| break # Found destination, so stop looking. |
| |
| for box in boxes.itervalues(): |
| box.close() |
| |