X-Git-Url: https://git.notmuchmail.org/git?p=notmuch;a=blobdiff_plain;f=cnotmuch%2Fdatabase.py;h=eb54626dccfa8964a98f09202fa5f4768efdaa92;hp=10251c42f3b6918f106d3d90bf5e886d41a84fea;hb=06f627df92b644a73c07096bed716d406d4f649d;hpb=55f1971437550aa382d0c2347a7be62dddcaa761 diff --git a/cnotmuch/database.py b/cnotmuch/database.py index 10251c42..eb54626d 100644 --- a/cnotmuch/database.py +++ b/cnotmuch/database.py @@ -1,20 +1,43 @@ import ctypes -from ctypes import c_int, c_char_p, c_void_p -from cnotmuch.globals import nmlib, STATUS, NotmuchError - +from ctypes import c_int, c_char_p, c_void_p, c_uint64 +from cnotmuch.globals import nmlib, STATUS, NotmuchError, Enum +import logging +from datetime import date class Database(object): - """ Wrapper around a notmuch_database_t + """Represents a notmuch database (wraps notmuch_database_t) - Do note that as soon as we tear down this object, all derived queries, - threads, and messages will be freed as well. + .. note:: Do note that as soon as we tear down this object, all underlying + derived objects such as queries, threads, messages, tags etc will + be freed by the underlying library as well. Accessing these objects + will lead to segfaults and other unexpected behavior. + + We implement reference counting, so that parent objects can be + automatically freed when they are not needed anymore, for example:: + + db = Database('path',create=True) + msgs = Query(db,'from:myself').search_messages() + + This returns a :class:`Messages` which internally contains + a reference to the parent :class:`Query` object. Otherwise + the Query() would be immediately freed, taking our *msgs* + down with it. + + In this case, the above Query() object will be + automatically freed whenever we delete all derived objects, + ie in our case: `del (msgs)` would also delete the parent + Query (but not the parent Database() as that is still + referenced from the variable *db* in which it is stored. + + Pretty much the same is valid for all other objects in the hierarchy, + such as :class:`Query`, :class:`Messages`, :class:`Message`, + and :class:`Tags`. """ - #constants - MODE_READ_ONLY = 0 - MODE_READ_WRITE = 1 + MODE = Enum(['READ_ONLY','READ_WRITE']) + """Constants: Mode in which to open the database""" _std_db_path = None - """Class attribute of users default database""" + """Class attribute to cache user's default database""" """notmuch_database_get_path (notmuch_database_t *database)""" _get_path = nmlib.notmuch_database_get_path @@ -36,12 +59,24 @@ class Database(object): _create = nmlib.notmuch_database_create _create.restype = c_void_p - def __init__(self, path=None, create=False, status= MODE_READ_ONLY): - """ Open or create a notmuch database - - If path is None, we will try to read a users notmuch configuration and - use his default database. - Throws a NotmuchError in case of failure. + def __init__(self, path=None, create=False, mode= MODE.READ_ONLY): + """If *path* is *None*, we will try to read a users notmuch + configuration and use his default database. If *create* is `True`, + the database will always be created in + :attr:`MODE.READ_WRITE` mode as creating an empty + database for reading only does not make a great deal of sense. + + :param path: Directory to open/create the database in (see + above for behavior if `None`) + :type path: `str` or `None` + :param create: False to open an existing, True to create a new + database. + :type create: bool + :param mdoe: Mode to open a database in. Always + :attr:`MODE`.READ_WRITE when creating a new one. + :type mode: :attr:`MODE` + :returns: Nothing + :exception: :exc:`NotmuchError` in case of failure. """ self._db = None if path is None: @@ -54,27 +89,40 @@ class Database(object): if create == False: self.open(path, status) else: - self.create(path, status) + self.create(path) - def create(self, path, status=MODE_READ_ONLY): - """ notmuch_database_create(const char *path) + def create(self, path): + """Creates a new notmuch database - :returns: Raises :exc:`notmuch.NotmuchError` in case - of any failure (after printing an error message on stderr). + This function wraps *notmuch_database_create(...)* and creates + a new notmuch database at *path*. It will always return a database in + :attr:`MODE`.READ_WRITE mode as creating an empty database + for reading only does not make a great deal of sense. + + :param path: A directory in which we should create the database. + :type path: str + :returns: Nothing + :exception: :exc:`NotmuchError` in case of any failure + (after printing an error message on stderr). """ - res = Database._create(path, status) + if self._db is not None: + raise NotmuchError( + message="Cannot create db, this Database() already has an open one.") + + res = Database._create(path, MODE.READ_WRITE) if res is None: raise NotmuchError( message="Could not create the specified database") self._db = res - def open(self, path, status= MODE_READ_ONLY): + def open(self, path, status= MODE.READ_ONLY): """calls notmuch_database_open :returns: Raises :exc:`notmuch.NotmuchError` in case of any failure (after printing an error message on stderr). """ + res = Database._open(path, status) if res is None: @@ -88,11 +136,13 @@ class Database(object): def find_message(self, msgid): """notmuch_database_find_message - :param msgid: The message id - :ptype msgid: string - :returns: Message() or None if no message is found or if an + :param msgid: The message id + :type msgid: string + :returns: :class:`Message` or `None` if no message is found or if an out-of-memory situation occurs. + :exception: :exc:`NotmuchError` with STATUS.NOT_INITIALIZED if + the database was not intitialized. """ if self._db is None: raise NotmuchError(STATUS.NOT_INITIALIZED) @@ -102,9 +152,9 @@ class Database(object): return Message(msg_p, self) def get_all_tags(self): - """Return a Tags() object (list of all tags found in the database) + """Returns :class:`Tags` with a list of all tags found in the database - :returns: Tags() object or raises :exc:`NotmuchError` with + :returns: :class:`Tags` object or raises :exc:`NotmuchError` with STATUS.NULL_POINTER on error """ if self._db is None: @@ -121,7 +171,7 @@ class Database(object): def __del__(self): """Close and free the notmuch database if needed""" if self._db is not None: - print("Freeing the database now") + logging.debug("Freeing the database now") nmlib.notmuch_database_close(self._db) def _get_user_default_db(self): @@ -139,27 +189,100 @@ class Database(object): @property def db_p(self): - """Returns a pointer to the current notmuch_database_t or None""" + """Property returning a pointer to the notmuch_database_t or `None`. + + This should normally not be needed by a user.""" return self._db +#------------------------------------------------------------------------------ +class Query(object): + """ Wrapper around a notmuch_query_t + + Do note that as soon as we tear down this object, all derived + threads, and messages will be freed as well. + """ + # constants + SORT_OLDEST_FIRST = 0 + SORT_NEWEST_FIRST = 1 + SORT_MESSAGE_ID = 2 + + """notmuch_query_create""" + _create = nmlib.notmuch_query_create + _create.restype = c_void_p + + """notmuch_query_search_messages""" + _search_messages = nmlib.notmuch_query_search_messages + _search_messages.restype = c_void_p + + def __init__(self, db, querystr): + """TODO: document""" + self._db = None + self._query = None + self.create(db, querystr) + + def create(self, db, querystr): + """db is a Database() and querystr a string + + raises NotmuchError STATUS.NOT_INITIALIZED if db is not inited and + STATUS.NULL_POINTER if the query creation failed (too little memory) + """ + if db.db_p is None: + raise NotmuchError(STATUS.NOT_INITIALIZED) + # create reference to parent db to keep it alive + self._db = db + + # create query, return None if too little mem available + query_p = Query._create(db.db_p, querystr) + if query_p is None: + NotmuchError(STATUS.NULL_POINTER) + self._query = query_p + + def set_sort(self, sort): + """notmuch_query_set_sort + + :param sort: one of Query.SORT_OLDEST_FIRST|SORT_NEWEST_FIRST|SORT_MESSAGE_ID + :returns: Nothing, but raises NotmuchError if query is not inited + """ + if self._query is None: + raise NotmuchError(STATUS.NOT_INITIALIZED) + + nmlib.notmuch_query_set_sort(self._query, sort) + + def search_messages(self): + """notmuch_query_search_messages + Returns Messages() or a raises a NotmuchError() + """ + if self._query is None: + raise NotmuchError(STATUS.NOT_INITIALIZED) + + msgs_p = Query._search_messages(self._query) + + if msgs_p is None: + NotmuchError(STATUS.NULL_POINTER) + + return Messages(msgs_p,self) + + + def __del__(self): + """Close and free the Query""" + if self._query is not None: + logging.debug("Freeing the Query now") + nmlib.notmuch_query_destroy (self._query) #------------------------------------------------------------------------------ class Tags(object): """Wrapper around notmuch_tags_t""" - class notmuch_tags_t(ctypes.Structure): - """the opaque tags struct that is returned by functions.""" - pass #notmuch_tags_get _get = nmlib.notmuch_tags_get _get.restype = c_char_p - def __init__(self, tags_p, db=None): + def __init__(self, tags_p, parent=None): """ msg_p is a pointer to an notmuch_message_t Structure. If it is None, we will raise an NotmuchError(STATUS.NULL_POINTER). - Is passed the db these tags are derived from, and saves a + Is passed the parent these tags are derived from, and saves a reference to it, so we can automatically delete the db object once all derived objects are dead. @@ -173,8 +296,9 @@ class Tags(object): NotmuchError(STATUS.NULL_POINTER) self._tags = tags_p - self._db = db - print "Inited Tags derived from %s" %(str(db)) + #save reference to parent object so we keep it alive + self._parent = parent + logging.debug("Inited Tags derived from %s" %(repr(parent))) def __iter__(self): """ Make Tags an iterator """ @@ -182,20 +306,124 @@ class Tags(object): def next(self): if self._tags is None: - raise StopIteration - nmlib.notmuch_tags_move_to_next(self._tags) + raise NotmuchError(STATUS.NOT_INITIALIZED) + if not nmlib.notmuch_tags_valid(self._tags): - print("Freeing the Tags now") - nmlib.notmuch_tags_destroy (self._tags) + self._tags = None raise StopIteration - return Tags._get (self._tags) + + tag = Tags._get (self._tags) + nmlib.notmuch_tags_move_to_next(self._tags) + return tag + + def __str__(self): + """str() of Tags() is a space separated list of tags + + This iterates over the list of Tags and will therefore 'exhaust' Tags() + """ + return " ".join(self) def __del__(self): """Close and free the notmuch tags""" if self._tags is not None: - print("Freeing the Tags now") + logging.debug("Freeing the Tags now") nmlib.notmuch_tags_destroy (self._tags) + +#------------------------------------------------------------------------------ +class Messages(object): + """Wrapper around notmuch_messages_t""" + + #notmuch_tags_get + _get = nmlib.notmuch_messages_get + _get.restype = c_void_p + + _collect_tags = nmlib.notmuch_messages_collect_tags + _collect_tags.restype = c_void_p + + def __init__(self, msgs_p, parent=None): + """ + msg_p is a pointer to an notmuch_messages_t Structure. If it is None, + we will raise an NotmuchError(STATUS.NULL_POINTER). + + If passed the parent query this Messages() is derived from, it saves a + reference to it, so we can automatically delete the parent query object + once all derived objects are dead. + + Messages() provides an iterator over all contained Message()s. + However, you will only be able to iterate over it once, + because the underlying C function only allows iterating once. + #TODO: make the iterator work more than once and cache the tags in + the Python object. + """ + if msgs_p is None: + NotmuchError(STATUS.NULL_POINTER) + + self._msgs = msgs_p + #store parent, so we keep them alive as long as self is alive + self._parent = parent + logging.debug("Inited Messages derived from %s" %(str(parent))) + + def collect_tags(self): + """ return the Tags() belonging to the messages + + Do note that collect_tags will iterate over the messages and + therefore will not allow further iterationsl + Raises NotmuchError(STATUS.NOT_INITIALIZED) if not inited + """ + if self._msgs is None: + raise NotmuchError(STATUS.NOT_INITIALIZED) + + # collect all tags (returns NULL on error) + tags_p = Messages._collect_tags (self._msgs) + #reset _msgs as we iterated over it and can do so only once + self._msgs = None + + if tags_p == None: + raise NotmuchError(STATUS.NULL_POINTER) + return Tags(tags_p, self) + + def __iter__(self): + """ Make Messages an iterator """ + return self + + def next(self): + if self._msgs is None: + raise NotmuchError(STATUS.NOT_INITIALIZED) + + if not nmlib.notmuch_messages_valid(self._msgs): + self._msgs = None + raise StopIteration + + msg = Message(Messages._get (self._msgs), self) + nmlib.notmuch_messages_move_to_next(self._msgs) + return msg + + def __len__(self): + """ Returns the number of contained messages + + :note: As this iterates over the messages, we will not be able to + iterate over them again (as in retrieve them)! + """ + if self._msgs is None: + raise NotmuchError(STATUS.NOT_INITIALIZED) + + i=0 + while nmlib.notmuch_messages_valid(self._msgs): + nmlib.notmuch_messages_move_to_next(self._msgs) + i += 1 + self._msgs = None + return i + + + + def __del__(self): + """Close and free the notmuch Messages""" + if self._msgs is not None: + logging.debug("Freeing the Messages now") + nmlib.notmuch_messages_destroy (self._msgs) + + #------------------------------------------------------------------------------ class Message(object): """Wrapper around notmuch_message_t""" @@ -211,6 +439,12 @@ class Message(object): _get_tags = nmlib.notmuch_message_get_tags _get_tags.restype = c_void_p + _get_date = nmlib.notmuch_message_get_date + _get_date.restype = c_uint64 + + _get_header = nmlib.notmuch_message_get_header + _get_header.restype = c_char_p + def __init__(self, msg_p, parent=None): """ msg_p is a pointer to an notmuch_message_t Structure. If it is None, @@ -223,8 +457,9 @@ class Message(object): if msg_p is None: NotmuchError(STATUS.NULL_POINTER) self._msg = msg_p + #keep reference to parent, so we keep it alive self._parent = parent - print "Inited Message derived from %s" %(str(parent)) + logging.debug("Inited Message derived from %s" %(str(parent))) def get_message_id(self): @@ -236,6 +471,28 @@ class Message(object): raise NotmuchError(STATUS.NOT_INITIALIZED) return Message._get_message_id(self._msg) + def get_date(self): + """returns time_t of the message date + + For the original textual representation of the Date header from the + message call notmuch_message_get_header() with a header value of + "date". + Raises NotmuchError(STATUS.NOT_INITIALIZED) if not inited + """ + if self._msg is None: + raise NotmuchError(STATUS.NOT_INITIALIZED) + return Message._get_date(self._msg) + + def get_header(self, header): + """ TODO document me""" + if self._msg is None: + raise NotmuchError(STATUS.NOT_INITIALIZED) + + #Returns NULL if any error occurs. + header = Message._get_header (self._msg, header) + if header == None: + raise NotmuchError(STATUS.NULL_POINTER) + return header def get_filename(self): """ return the msg filename @@ -260,8 +517,20 @@ class Message(object): raise NotmuchError(STATUS.NULL_POINTER) return Tags(tags_p, self) + def __str__(self): + """A message() is represented by a 1-line summary""" + msg = {} + msg['from'] = self.get_header('from') + msg['tags'] = str(self.get_tags()) + msg['date'] = date.fromtimestamp(self.get_date()) + return "%(from)s (%(date)s) (%(tags)s)" % (msg) + + def format_as_text(self): + """ Output like notmuch show """ + return str(self) + def __del__(self): """Close and free the notmuch Message""" if self._msg is not None: - print("Freeing the Message now") + logging.debug("Freeing the Message now") nmlib.notmuch_message_destroy (self._msg)