2 This file is part of notmuch.
4 Notmuch is free software: you can redistribute it and/or modify it
5 under the terms of the GNU General Public License as published by the
6 Free Software Foundation, either version 3 of the License, or (at your
7 option) any later version.
9 Notmuch is distributed in the hope that it will be useful, but WITHOUT
10 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 You should have received a copy of the GNU General Public License
15 along with notmuch. If not, see <http://www.gnu.org/licenses/>.
17 Copyright 2010 Sebastian Spaeth <Sebastian@SSpaeth.de>'
22 from ctypes import c_char_p, c_void_p, c_uint, c_long, byref, POINTER
23 from notmuch.globals import (
38 from notmuch.message import Message
39 from notmuch.tag import Tags
40 from .query import Query
42 class Database(object):
43 """The :class:`Database` is the highest-level object that notmuch
44 provides. It references a notmuch database, and can be opened in
45 read-only or read-write mode. A :class:`Query` can be derived from
46 or be applied to a specific database to find messages. Also adding
47 and removing messages to the database happens via this
48 object. Modifications to the database are not atmic by default (see
49 :meth:`begin_atomic`) and once a database has been modified, all
50 other database objects pointing to the same data-base will throw an
51 :exc:`XapianError` as the underlying database has been
52 modified. Close and reopen the database to continue working with it.
54 :class:`Database` objects implement the context manager protocol
55 so you can use the :keyword:`with` statement to ensure that the
56 database is properly closed.
60 Any function in this class can and will throw an
61 :exc:`NotInitializedError` if the database was not intitialized
66 Do remember that as soon as we tear down (e.g. via `del db`) this
67 object, all underlying derived objects such as queries, threads,
68 messages, tags etc will be freed by the underlying library as well.
69 Accessing these objects will lead to segfaults and other unexpected
70 behavior. See above for more details.
73 """Class attribute to cache user's default database"""
75 MODE = Enum(['READ_ONLY', 'READ_WRITE'])
76 """Constants: Mode in which to open the database"""
78 """notmuch_database_get_directory"""
79 _get_directory = nmlib.notmuch_database_get_directory
80 _get_directory.argtypes = [NotmuchDatabaseP, c_char_p]
81 _get_directory.restype = NotmuchDirectoryP
83 """notmuch_database_get_path"""
84 _get_path = nmlib.notmuch_database_get_path
85 _get_path.argtypes = [NotmuchDatabaseP]
86 _get_path.restype = c_char_p
88 """notmuch_database_get_version"""
89 _get_version = nmlib.notmuch_database_get_version
90 _get_version.argtypes = [NotmuchDatabaseP]
91 _get_version.restype = c_uint
93 """notmuch_database_open"""
94 _open = nmlib.notmuch_database_open
95 _open.argtypes = [c_char_p, c_uint]
96 _open.restype = NotmuchDatabaseP
98 """notmuch_database_upgrade"""
99 _upgrade = nmlib.notmuch_database_upgrade
100 _upgrade.argtypes = [NotmuchDatabaseP, c_void_p, c_void_p]
101 _upgrade.restype = c_uint
103 """ notmuch_database_find_message"""
104 _find_message = nmlib.notmuch_database_find_message
105 _find_message.argtypes = [NotmuchDatabaseP, c_char_p,
106 POINTER(NotmuchMessageP)]
107 _find_message.restype = c_uint
109 """notmuch_database_find_message_by_filename"""
110 _find_message_by_filename = nmlib.notmuch_database_find_message_by_filename
111 _find_message_by_filename.argtypes = [NotmuchDatabaseP, c_char_p,
112 POINTER(NotmuchMessageP)]
113 _find_message_by_filename.restype = c_uint
115 """notmuch_database_get_all_tags"""
116 _get_all_tags = nmlib.notmuch_database_get_all_tags
117 _get_all_tags.argtypes = [NotmuchDatabaseP]
118 _get_all_tags.restype = NotmuchTagsP
120 """notmuch_database_create"""
121 _create = nmlib.notmuch_database_create
122 _create.argtypes = [c_char_p]
123 _create.restype = NotmuchDatabaseP
125 def __init__(self, path = None, create = False,
126 mode = MODE.READ_ONLY):
127 """If *path* is `None`, we will try to read a users notmuch
128 configuration and use his configured database. The location of the
129 configuration file can be specified through the environment variable
130 *NOTMUCH_CONFIG*, falling back to the default `~/.notmuch-config`.
132 If *create* is `True`, the database will always be created in
133 :attr:`MODE`.READ_WRITE mode. Default mode for opening is READ_ONLY.
135 :param path: Directory to open/create the database in (see
136 above for behavior if `None`)
137 :type path: `str` or `None`
138 :param create: Pass `False` to open an existing, `True` to create a new
141 :param mode: Mode to open a database in. Is always
142 :attr:`MODE`.READ_WRITE when creating a new one.
143 :type mode: :attr:`MODE`
144 :raises: :exc:`NotmuchError` or derived exception in case of
149 # no path specified. use a user's default database
150 if Database._std_db_path is None:
151 #the following line throws a NotmuchError if it fails
152 Database._std_db_path = self._get_user_default_db()
153 path = Database._std_db_path
156 self.open(path, mode)
163 def _assert_db_is_initialized(self):
164 """Raises :exc:`NotInitializedError` if self._db is `None`"""
166 raise NotInitializedError()
168 def create(self, path):
169 """Creates a new notmuch database
171 This function is used by __init__() and usually does not need
172 to be called directly. It wraps the underlying
173 *notmuch_database_create* function and creates a new notmuch
174 database at *path*. It will always return a database in :attr:`MODE`
175 .READ_WRITE mode as creating an empty database for
176 reading only does not make a great deal of sense.
178 :param path: A directory in which we should create the database.
180 :raises: :exc:`NotmuchError` in case of any failure
181 (possibly after printing an error message on stderr).
183 if self._db is not None:
184 raise NotmuchError(message="Cannot create db, this Database() "
185 "already has an open one.")
187 res = Database._create(_str(path), Database.MODE.READ_WRITE)
191 message="Could not create the specified database")
194 def open(self, path, mode=0):
195 """Opens an existing database
197 This function is used by __init__() and usually does not need
198 to be called directly. It wraps the underlying
199 *notmuch_database_open* function.
201 :param status: Open the database in read-only or read-write mode
202 :type status: :attr:`MODE`
203 :raises: Raises :exc:`NotmuchError` in case of any failure
204 (possibly after printing an error message on stderr).
206 res = Database._open(_str(path), mode)
209 raise NotmuchError(message="Could not open the specified database")
212 _close = nmlib.notmuch_database_close
213 _close.argtypes = [NotmuchDatabaseP]
214 _close.restype = None
217 """Close and free the notmuch database if needed"""
218 if self._db is not None:
219 self._close(self._db)
224 Implements the context manager protocol.
228 def __exit__(self, exc_type, exc_value, traceback):
230 Implements the context manager protocol.
235 """Returns the file path of an open database"""
236 self._assert_db_is_initialized()
237 return Database._get_path(self._db).decode('utf-8')
239 def get_version(self):
240 """Returns the database format version
242 :returns: The database version as positive integer
244 self._assert_db_is_initialized()
245 return Database._get_version(self._db)
247 _needs_upgrade = nmlib.notmuch_database_needs_upgrade
248 _needs_upgrade.argtypes = [NotmuchDatabaseP]
249 _needs_upgrade.restype = bool
251 def needs_upgrade(self):
252 """Does this database need to be upgraded before writing to it?
254 If this function returns `True` then no functions that modify the
255 database (:meth:`add_message`,
256 :meth:`Message.add_tag`, :meth:`Directory.set_mtime`,
257 etc.) will work unless :meth:`upgrade` is called successfully first.
259 :returns: `True` or `False`
261 self._assert_db_is_initialized()
262 return self._needs_upgrade(self._db)
265 """Upgrades the current database
267 After opening a database in read-write mode, the client should
268 check if an upgrade is needed (notmuch_database_needs_upgrade) and
269 if so, upgrade with this function before making any modifications.
271 NOT IMPLEMENTED: The optional progress_notify callback can be
272 used by the caller to provide progress indication to the
273 user. If non-NULL it will be called periodically with
274 'progress' as a floating-point value in the range of [0.0..1.0]
275 indicating the progress made so far in the upgrade process.
277 :TODO: catch exceptions, document return values and etc...
279 self._assert_db_is_initialized()
280 status = Database._upgrade(self._db, None, None)
281 #TODO: catch exceptions, document return values and etc
284 _begin_atomic = nmlib.notmuch_database_begin_atomic
285 _begin_atomic.argtypes = [NotmuchDatabaseP]
286 _begin_atomic.restype = c_uint
288 def begin_atomic(self):
289 """Begin an atomic database operation
291 Any modifications performed between a successful
292 :meth:`begin_atomic` and a :meth:`end_atomic` will be applied to
293 the database atomically. Note that, unlike a typical database
294 transaction, this only ensures atomicity, not durability;
295 neither begin nor end necessarily flush modifications to disk.
297 :returns: :attr:`STATUS`.SUCCESS or raises
298 :raises: :exc:`NotmuchError`: :attr:`STATUS`.XAPIAN_EXCEPTION
299 Xapian exception occurred; atomic section not entered.
301 *Added in notmuch 0.9*"""
302 self._assert_db_is_initialized()
303 status = self._begin_atomic(self._db)
304 if status != STATUS.SUCCESS:
305 raise NotmuchError(status)
308 _end_atomic = nmlib.notmuch_database_end_atomic
309 _end_atomic.argtypes = [NotmuchDatabaseP]
310 _end_atomic.restype = c_uint
312 def end_atomic(self):
313 """Indicate the end of an atomic database operation
315 See :meth:`begin_atomic` for details.
317 :returns: :attr:`STATUS`.SUCCESS or raises
321 :attr:`STATUS`.XAPIAN_EXCEPTION
322 A Xapian exception occurred; atomic section not
324 :attr:`STATUS`.UNBALANCED_ATOMIC:
325 end_atomic has been called more times than begin_atomic.
327 *Added in notmuch 0.9*"""
328 self._assert_db_is_initialized()
329 status = self._end_atomic(self._db)
330 if status != STATUS.SUCCESS:
331 raise NotmuchError(status)
334 def get_directory(self, path):
335 """Returns a :class:`Directory` of path,
336 (creating it if it does not exist(?))
340 This call needs a writeable database in
341 :attr:`Database.MODE`.READ_WRITE mode. The underlying library will
342 exit the program if this method is used on a read-only database!
344 :param path: An unicode string containing the path relative to the path
345 of database (see :meth:`get_path`), or else should be an absolute
346 path with initial components that match the path of 'database'.
347 :returns: :class:`Directory` or raises an exception.
349 :exc:`NotmuchError` with :attr:`STATUS`.FILE_ERROR
350 If path is not relative database or absolute with initial
351 components same as database.
353 self._assert_db_is_initialized()
354 # sanity checking if path is valid, and make path absolute
355 if path and path[0] == os.sep:
356 # we got an absolute path
357 if not path.startswith(self.get_path()):
358 # but its initial components are not equal to the db path
359 raise FileError('Database().get_directory() called '
360 'with a wrong absolute path')
363 #we got a relative path, make it absolute
364 abs_dirpath = os.path.abspath(os.path.join(self.get_path(), path))
366 dir_p = Database._get_directory(self._db, _str(path))
368 # return the Directory, init it with the absolute path
369 return Directory(abs_dirpath, dir_p, self)
371 _add_message = nmlib.notmuch_database_add_message
372 _add_message.argtypes = [NotmuchDatabaseP, c_char_p,
373 POINTER(NotmuchMessageP)]
374 _add_message.restype = c_uint
376 def add_message(self, filename, sync_maildir_flags=False):
377 """Adds a new message to the database
379 :param filename: should be a path relative to the path of the
380 open database (see :meth:`get_path`), or else should be an
381 absolute filename with initial components that match the
382 path of the database.
384 The file should be a single mail message (not a
385 multi-message mbox) that is expected to remain at its
386 current location, since the notmuch database will reference
387 the filename, and will not copy the entire contents of the
390 :param sync_maildir_flags: If the message contains Maildir
391 flags, we will -depending on the notmuch configuration- sync
392 those tags to initial notmuch tags, if set to `True`. It is
393 `False` by default to remain consistent with the libnotmuch
394 API. You might want to look into the underlying method
395 :meth:`Message.maildir_flags_to_tags`.
397 :returns: On success, we return
399 1) a :class:`Message` object that can be used for things
400 such as adding tags to the just-added message.
401 2) one of the following :attr:`STATUS` values:
403 :attr:`STATUS`.SUCCESS
404 Message successfully added to database.
405 :attr:`STATUS`.DUPLICATE_MESSAGE_ID
406 Message has the same message ID as another message already
407 in the database. The new filename was successfully added
408 to the list of the filenames for the existing message.
410 :rtype: 2-tuple(:class:`Message`, :attr:`STATUS`)
412 :raises: Raises a :exc:`NotmuchError` with the following meaning.
413 If such an exception occurs, nothing was added to the database.
415 :attr:`STATUS`.FILE_ERROR
416 An error occurred trying to open the file, (such as
417 permission denied, or file not found, etc.).
418 :attr:`STATUS`.FILE_NOT_EMAIL
419 The contents of filename don't look like an email
421 :attr:`STATUS`.READ_ONLY_DATABASE
422 Database was opened in read-only mode so no message can
425 self._assert_db_is_initialized()
426 msg_p = NotmuchMessageP()
427 status = self._add_message(self._db, _str(filename), byref(msg_p))
429 if not status in [STATUS.SUCCESS, STATUS.DUPLICATE_MESSAGE_ID]:
430 raise NotmuchError(status)
432 #construct Message() and return
433 msg = Message(msg_p, self)
434 #automatic sync initial tags from Maildir flags
435 if sync_maildir_flags:
436 msg.maildir_flags_to_tags()
439 _remove_message = nmlib.notmuch_database_remove_message
440 _remove_message.argtypes = [NotmuchDatabaseP, c_char_p]
441 _remove_message.restype = c_uint
443 def remove_message(self, filename):
444 """Removes a message (filename) from the given notmuch database
446 Note that only this particular filename association is removed from
447 the database. If the same message (as determined by the message ID)
448 is still available via other filenames, then the message will
449 persist in the database for those filenames. When the last filename
450 is removed for a particular message, the database content for that
451 message will be entirely removed.
453 :returns: A :attr:`STATUS` value with the following meaning:
455 :attr:`STATUS`.SUCCESS
456 The last filename was removed and the message was removed
458 :attr:`STATUS`.DUPLICATE_MESSAGE_ID
459 This filename was removed but the message persists in the
460 database with at least one other filename.
462 :raises: Raises a :exc:`NotmuchError` with the following meaning.
463 If such an exception occurs, nothing was removed from the
466 :attr:`STATUS`.READ_ONLY_DATABASE
467 Database was opened in read-only mode so no message can be
470 self._assert_db_is_initialized()
471 return self._remove_message(self._db, _str(filename))
473 def find_message(self, msgid):
474 """Returns a :class:`Message` as identified by its message ID
476 Wraps the underlying *notmuch_database_find_message* function.
478 :param msgid: The message ID
479 :type msgid: unicode or str
480 :returns: :class:`Message` or `None` if no message is found.
482 :exc:`OutOfMemoryError`
483 If an Out-of-memory occured while constructing the message.
485 In case of a Xapian Exception. These exceptions
486 include "Database modified" situations, e.g. when the
487 notmuch database has been modified by another program
488 in the meantime. In this case, you should close and
489 reopen the database and retry.
490 :exc:`NotInitializedError` if
491 the database was not intitialized.
493 self._assert_db_is_initialized()
494 msg_p = NotmuchMessageP()
495 status = Database._find_message(self._db, _str(msgid), byref(msg_p))
496 if status != STATUS.SUCCESS:
497 raise NotmuchError(status)
498 return msg_p and Message(msg_p, self) or None
500 def find_message_by_filename(self, filename):
501 """Find a message with the given filename
505 This call needs a writeable database in
506 :attr:`Database.MODE`.READ_WRITE mode. The underlying library will
507 exit the program if this method is used on a read-only database!
509 :returns: If the database contains a message with the given
510 filename, then a class:`Message:` is returned. This
511 function returns None if no message is found with the given
515 :exc:`OutOfMemoryError`
516 If an Out-of-memory occured while constructing the message.
518 In case of a Xapian Exception. These exceptions
519 include "Database modified" situations, e.g. when the
520 notmuch database has been modified by another program
521 in the meantime. In this case, you should close and
522 reopen the database and retry.
523 :exc:`NotInitializedError` if
524 the database was not intitialized.
526 *Added in notmuch 0.9*"""
527 self._assert_db_is_initialized()
528 msg_p = NotmuchMessageP()
529 status = Database._find_message_by_filename(self._db, _str(filename),
531 if status != STATUS.SUCCESS:
532 raise NotmuchError(status)
533 return msg_p and Message(msg_p, self) or None
535 def get_all_tags(self):
536 """Returns :class:`Tags` with a list of all tags found in the database
538 :returns: :class:`Tags`
539 :execption: :exc:`NotmuchError` with :attr:`STATUS`.NULL_POINTER
542 self._assert_db_is_initialized()
543 tags_p = Database._get_all_tags(self._db)
545 raise NullPointerError()
546 return Tags(tags_p, self)
548 def create_query(self, querystring):
549 """Returns a :class:`Query` derived from this database
551 This is a shorthand method for doing::
554 # Automatically frees the Database() when 'q' is deleted
556 q = Database(dbpath).create_query('from:"Biene Maja"')
558 # long version, which is functionally equivalent but will keep the
559 # Database in the 'db' variable around after we delete 'q':
561 db = Database(dbpath)
562 q = Query(db,'from:"Biene Maja"')
564 This function is a python extension and not in the underlying C API.
566 return Query(self, querystring)
569 return "'Notmuch DB " + self.get_path() + "'"
571 def _get_user_default_db(self):
572 """ Reads a user's notmuch config and returns his db location
574 Throws a NotmuchError if it cannot find it"""
577 from configparser import SafeConfigParser
580 from ConfigParser import SafeConfigParser
582 config = SafeConfigParser()
583 conf_f = os.getenv('NOTMUCH_CONFIG',
584 os.path.expanduser('~/.notmuch-config'))
585 config.readfp(codecs.open(conf_f, 'r', 'utf-8'))
586 if not config.has_option('database', 'path'):
587 raise NotmuchError(message="No DB path specified"
588 " and no user default found")
589 return config.get('database', 'path')
593 """Property returning a pointer to `notmuch_database_t` or `None`
595 This should normally not be needed by a user (and is not yet
596 guaranteed to remain stable in future versions).
601 class Directory(object):
602 """Represents a directory entry in the notmuch directory
604 Modifying attributes of this object will modify the
605 database, not the real directory attributes.
607 The Directory object is usually derived from another object
608 e.g. via :meth:`Database.get_directory`, and will automatically be
609 become invalid whenever that parent is deleted. You should
610 therefore initialized this object handing it a reference to the
611 parent, preventing the parent from automatically being garbage
615 """notmuch_directory_get_mtime"""
616 _get_mtime = nmlib.notmuch_directory_get_mtime
617 _get_mtime.argtypes = [NotmuchDirectoryP]
618 _get_mtime.restype = c_long
620 """notmuch_directory_set_mtime"""
621 _set_mtime = nmlib.notmuch_directory_set_mtime
622 _set_mtime.argtypes = [NotmuchDirectoryP, c_long]
623 _set_mtime.restype = c_uint
625 """notmuch_directory_get_child_files"""
626 _get_child_files = nmlib.notmuch_directory_get_child_files
627 _get_child_files.argtypes = [NotmuchDirectoryP]
628 _get_child_files.restype = NotmuchFilenamesP
630 """notmuch_directory_get_child_directories"""
631 _get_child_directories = nmlib.notmuch_directory_get_child_directories
632 _get_child_directories.argtypes = [NotmuchDirectoryP]
633 _get_child_directories.restype = NotmuchFilenamesP
635 def _assert_dir_is_initialized(self):
636 """Raises a NotmuchError(:attr:`STATUS`.NOT_INITIALIZED)
639 raise NotInitializedError()
641 def __init__(self, path, dir_p, parent):
643 :param path: The absolute path of the directory object.
644 :param dir_p: The pointer to an internal notmuch_directory_t object.
645 :param parent: The object this Directory is derived from
646 (usually a :class:`Database`). We do not directly use
647 this, but store a reference to it as long as
648 this Directory object lives. This keeps the
653 self._parent = parent
655 def set_mtime(self, mtime):
656 """Sets the mtime value of this directory in the database
658 The intention is for the caller to use the mtime to allow efficient
659 identification of new messages to be added to the database. The
660 recommended usage is as follows:
662 * Read the mtime of a directory from the filesystem
664 * Call :meth:`Database.add_message` for all mail files in
667 * Call notmuch_directory_set_mtime with the mtime read from the
668 filesystem. Then, when wanting to check for updates to the
669 directory in the future, the client can call :meth:`get_mtime`
670 and know that it only needs to add files if the mtime of the
671 directory and files are newer than the stored timestamp.
675 :meth:`get_mtime` function does not allow the caller to
676 distinguish a timestamp of 0 from a non-existent timestamp. So
677 don't store a timestamp of 0 unless you are comfortable with
680 :param mtime: A (time_t) timestamp
681 :raises: :exc:`XapianError` a Xapian exception occurred, mtime
683 :raises: :exc:`ReadOnlyDatabaseError` the database was opened
684 in read-only mode so directory mtime cannot be modified
685 :raises: :exc:`NotInitializedError` the directory object has not
688 self._assert_dir_is_initialized()
689 status = Directory._set_mtime(self._dir_p, mtime)
691 if status != STATUS.SUCCESS:
692 raise NotmuchError(status)
695 """Gets the mtime value of this directory in the database
697 Retrieves a previously stored mtime for this directory.
699 :param mtime: A (time_t) timestamp
700 :raises: :exc:`NotmuchError`:
702 :attr:`STATUS`.NOT_INITIALIZED
703 The directory has not been initialized
705 self._assert_dir_is_initialized()
706 return Directory._get_mtime(self._dir_p)
708 # Make mtime attribute a property of Directory()
709 mtime = property(get_mtime, set_mtime, doc="""Property that allows getting
710 and setting of the Directory *mtime* (read-write)
712 See :meth:`get_mtime` and :meth:`set_mtime` for usage and
713 possible exceptions.""")
715 def get_child_files(self):
716 """Gets a Filenames iterator listing all the filenames of
717 messages in the database within the given directory.
719 The returned filenames will be the basename-entries only (not
722 self._assert_dir_is_initialized()
723 files_p = Directory._get_child_files(self._dir_p)
724 return Filenames(files_p, self)
726 def get_child_directories(self):
727 """Gets a :class:`Filenames` iterator listing all the filenames of
728 sub-directories in the database within the given directory
730 The returned filenames will be the basename-entries only (not
733 self._assert_dir_is_initialized()
734 files_p = Directory._get_child_directories(self._dir_p)
735 return Filenames(files_p, self)
739 """Returns the absolute path of this Directory (read-only)"""
743 """Object representation"""
744 return "<notmuch Directory object '%s'>" % self._path
746 _destroy = nmlib.notmuch_directory_destroy
747 _destroy.argtypes = [NotmuchDirectoryP]
748 _destroy.argtypes = None
751 """Close and free the Directory"""
752 if self._dir_p is not None:
753 self._destroy(self._dir_p)
756 class Filenames(object):
757 """An iterator over File- or Directory names stored in the database"""
759 #notmuch_filenames_get
760 _get = nmlib.notmuch_filenames_get
761 _get.argtypes = [NotmuchFilenamesP]
762 _get.restype = c_char_p
764 def __init__(self, files_p, parent):
766 :param files_p: The pointer to an internal notmuch_filenames_t object.
767 :param parent: The object this Directory is derived from
768 (usually a Directory()). We do not directly use
769 this, but store a reference to it as long as
770 this Directory object lives. This keeps the
773 self._files_p = files_p
774 self._parent = parent
777 """ Make Filenames an iterator """
780 _valid = nmlib.notmuch_filenames_valid
781 _valid.argtypes = [NotmuchFilenamesP]
782 _valid.restype = bool
784 _move_to_next = nmlib.notmuch_filenames_move_to_next
785 _move_to_next.argtypes = [NotmuchFilenamesP]
786 _move_to_next.restype = None
789 if not self._files_p:
790 raise NotInitializedError()
792 if not self._valid(self._files_p):
796 file_ = Filenames._get(self._files_p)
797 self._move_to_next(self._files_p)
798 return file_.decode('utf-8', 'ignore')
799 next = __next__ # python2.x iterator protocol compatibility
802 """len(:class:`Filenames`) returns the number of contained files
806 As this iterates over the files, we will not be able to
807 iterate over them again! So this will fail::
810 files = Database().get_directory('').get_child_files()
811 if len(files) > 0: # this 'exhausts' msgs
813 # NotmuchError(:attr:`STATUS`.NOT_INITIALIZED)
814 for file in files: print file
816 if not self._files_p:
817 raise NotInitializedError()
820 while self._valid(self._files_p):
821 self._move_to_next(self._files_p)
826 _destroy = nmlib.notmuch_filenames_destroy
827 _destroy.argtypes = [NotmuchFilenamesP]
828 _destroy.restype = None
831 """Close and free Filenames"""
832 if self._files_p is not None:
833 self._destroy(self._files_p)