import collections import contextlib import os import pathlib import weakref import notdb._base as base import notdb._capi as capi import notdb._errors as errors import notdb._tags as tags __all__ = ['Message'] class Message(base.NotmuchObject): """An email message stored in the notmuch database. This should not be directly created, instead it will be returned by calling methods on :class:`Database`. A message keeps a reference to the database object since the database object can not be released while the message is in use. Note that this represents a message in the notmuch database. For full email functionality you may want to use the :mod:`email` package from Python's standard library. You could e.g. create this as such:: notmuch_msg = db.get_message(msgid) # or from a query parser = email.parser.BytesParser(policy=email.policy.default) with notmuch_msg.path.open('rb) as fp: email_msg = parser.parse(fp) Most commonly the functionality provided by notmuch is sufficient to read email however. Messages are considered equal when they have the same message ID. This is how libnotmuch treats messages as well, the :meth:`pathnames` function returns multiple results for duplicates. :param parent: The parent object. This is probably one off a :class:`Database`, :class:`Thread` or :class:`Query`. :type parent: NotmuchObject :param db: The database instance this message is associated with. This could be the same as the parent. :type db: Database :param msg_p: The C pointer to the ``notmuch_message_t``. :type msg_p: :param dup: Whether the message was a duplicate on insertion. :type dup: None or bool """ _msg_p = base.MemoryPointer() def __init__(self, parent, msg_p, *, db): self._parent = parent self._msg_p = msg_p self._db = db @property def alive(self): if not self._parent.alive: return False try: self._msg_p except errors.ObjectDestroyedError: return False else: return True def __del__(self): self._destroy() def _destroy(self): if self.alive: capi.lib.notmuch_message_destroy(self._msg_p) self._msg_p = None @property def messageid(self): """The message ID as a string. The message ID is decoded with the ignore error handler. This is fine as long as the message ID is well formed. If it is not valid ASCII then this will be lossy. So if you need to be able to write the exact same message ID back you should use :attr:`messageidb`. Note that notmuch will decode the message ID value and thus strip off the surrounding ``<`` and ``>`` characters. This is different from Python's :mod:`email` package behaviour which leaves these characters in place. :returns: The message ID. :rtype: :class:`BinString`, this is a normal str but calling bytes() on it will return the original bytes used to create it. :raises ObjectDestroyedError: if used after destoryed. """ ret = capi.lib.notmuch_message_get_message_id(self._msg_p) return base.BinString(capi.ffi.string(ret)) @property def threadid(self): """The thread ID. The thread ID is decoded with the surrogateescape error handler so that it is possible to reconstruct the original thread ID if it is not valid UTF-8. :returns: The thread ID. :rtype: :class:`BinString`, this is a normal str but calling bytes() on it will return the original bytes used to create it. :raises ObjectDestroyedError: if used after destoryed. """ ret = capi.lib.notmuch_message_get_thread_id(self._msg_p) return base.BinString(capi.ffi.string(ret)) @property def path(self): """A pathname of the message as a pathlib.Path instance. If multiple files in the database contain the same message ID this will be just one of the files, chosen at random. :raises ObjectDestroyedError: if used after destoryed. """ ret = capi.lib.notmuch_message_get_filename(self._msg_p) return pathlib.Path(os.fsdecode(capi.ffi.string(ret))) @property def pathb(self): """A pathname of the message as a bytes object. See :attr:`path` for details, this is the same but does return the path as a bytes object which is faster but less convenient. :raises ObjectDestroyedError: if used after destoryed. """ ret = capi.lib.notmuch_message_get_filename(self._msg_p) return capi.ffi.string(ret) def filenames(self): """Return an iterator of all files for this message. If multiple files contained the same message ID they will all be returned here. The files are returned as intances of :class:`pathlib.Path`. :returns: Iterator yielding :class:`pathlib.Path` instances. :rtype: iter :raises ObjectDestroyedError: if used after destoryed. """ fnames_p = capi.lib.notmuch_message_get_filenames(self._msg_p) return PathIter(self, fnames_p) def filenamesb(self): """Return an iterator of all files for this message. This is like :meth:`pathnames` but the files are returned as byte objects instead. :returns: Iterator yielding :class:`bytes` instances. :rtype: iter :raises ObjectDestroyedError: if used after destoryed. """ fnames_p = capi.lib.notmuch_message_get_filenames(self._msg_p) return FilenamesIter(self, fnames_p) @property def ghost(self): """Indicates whether this message is a ghost message. A ghost message if a message which we know exists, but it has no files or content associated with it. This can happen if it was referenced by some other message. Only the :attr:`messageid` and :attr:`threadid` attributes are valid for it. :raises ObjectDestroyedError: if used after destoryed. """ ret = capi.lib.notmuch_message_get_flag( self._msg_p, capi.lib.NOTMUCH_MESSAGE_FLAG_GHOST) return bool(ret) @property def excluded(self): """Indicates whether this message was excluded from the query. When a message is created from a search, sometimes messages that where excluded by the search query could still be returned by it, e.g. because they are part of a thread matching the query. the :meth:`Database.query` method allows these messages to be flagged, which results in this property being set to *True*. :raises ObjectDestroyedError: if used after destoryed. """ ret = capi.lib.notmuch_message_get_flag( self._msg_p, capi.lib.NOTMUCH_MESSAGE_FLAG_EXCLUDED) return bool(ret) @property def date(self): """The message date as an integer. The time the message was sent as an integer number of seconds since the *epoch*, 1 Jan 1970. This is derived from the message's header, you can get the original header value with :meth:`header`. :raises ObjectDestroyedError: if used after destoryed. """ return capi.lib.notmuch_message_get_date(self._msg_p) def header(self, name): """Return the value of the named header. Returns the header from notmuch, some common headers are stored in the database, others are read from the file. Headers are returned with their newlines stripped and collapsed concatenated together if they occur multiple times. You may be better off using the standard library email package's ``email.message_from_file(msg.path.open())`` if that is not sufficient for you. :param header: Case-insensitive header name to retrieve. :type header: str or bytes :returns: The header value, an empty string if the header is not present. :rtype: str :raises LookupError: if the header is not present. :raises NullPointerError: For unexpected notmuch errors. :raises ObjectDestroyedError: if used after destoryed. """ # The returned is supposedly guaranteed to be UTF-8. Header # names must be ASCII as per RFC x822. if isinstance(name, str): name = name.encode('ascii') ret = capi.lib.notmuch_message_get_header(self._msg_p, name) if ret == capi.ffi.NULL: raise errors.NullPointerError() hdr = capi.ffi.string(ret) if not hdr: raise LookupError return hdr.decode(encoding='utf-8') @property def tags(self): """The tags associated with the message. This behaves as a set. But removing and adding items to the set removes and adds them to the message in the database. :raises ReadOnlyDatabaseError: When manipulating tags on a database opened in read-only mode. :raises ObjectDestroyedError: if used after destoryed. """ try: ref = self._cached_tagset except AttributeError: tagset = None else: tagset = ref() if tagset is None: tagset = tags.MutableTagSet( self, '_msg_p', capi.lib.notmuch_message_get_tags) self._cached_tagset = weakref.ref(tagset) return tagset @contextlib.contextmanager def frozen(self): """Context manager to freeze the message state. This allows you to perform atomic tag updates:: with msg.frozen(): msg.tags.clear() msg.tags.add('foo') Using This would ensure the message never ends up with no tags applied at all. It is safe to nest calls to this context manager. :raises ReadOnlyDatabaseError: if the database is opened in read-only mode. :raises UnbalancedFreezeThawError: if you somehow managed to call __exit__ of this context manager more than once. Why did you do that? :raises ObjectDestroyedError: if used after destoryed. """ ret = capi.lib.notmuch_message_freeze(self._msg_p) if ret != capi.lib.NOTMUCH_STATUS_SUCCESS: raise errors.NotmuchError(ret) self._frozen = True try: yield except Exception: # Only way to "rollback" these changes is to destroy # ourselves and re-create. Behold. msgid = self.messageid self._destroy() with contextlib.suppress(Exception): new = self._db.find(msgid) self._msg_p = new._msg_p new._msg_p = None del new raise else: ret = capi.lib.notmuch_message_thaw(self._msg_p) if ret != capi.lib.NOTMUCH_STATUS_SUCCESS: raise errors.NotmuchError(ret) self._frozen = False @property def properties(self): """A map of arbitrary key-value pairs associated with the message. Be aware that properties may be used by other extensions to store state in. So delete or modify with care. The properties map is somewhat special. It is essentially a multimap-like structure where each key can have multiple values. Therefore accessing a single item using :meth:`PropertiesMap.get` or :meth:`PropertiesMap.__getitem__` will only return you the *first* item if there are multiple and thus are only recommended if you know there to be only one value. Instead the map has an additional :meth:`PropertiesMap.all` method which can be used to retrieve all properties of a given key. This method also allows iterating of a a subset of the keys starting with a given prefix. """ try: ref = self._cached_props except AttributeError: props = None else: props = ref() if props is None: props = PropertiesMap(self, '_msg_p') self._cached_props = weakref.ref(props) return props def replies(self): """Return an iterator of all replies to this message. This method will only work if the message was created from a thread. Otherwise it will yield no results. :returns: An iterator yielding :class:`Message` instances. :rtype: MessageIter """ # The notmuch_messages_valid call accepts NULL and this will # become an empty iterator, raising StopIteration immediately. # Hence no return value checking here. msgs_p = capi.lib.notmuch_message_get_replies(self._msg_p) return MessageIter(self, msgs_p, db=self._db) def __hash__(self): return hash(self.messageid) def __eq__(self, other): if isinstance(other, self.__class__): return self.messageid == other.messageid class FilenamesIter(base.NotmuchIter): """Iterator for binary filenames objects.""" def __init__(self, parent, iter_p): super().__init__(parent, iter_p, fn_destroy=capi.lib.notmuch_filenames_destroy, fn_valid=capi.lib.notmuch_filenames_valid, fn_get=capi.lib.notmuch_filenames_get, fn_next=capi.lib.notmuch_filenames_move_to_next) def __next__(self): fname = super().__next__() return capi.ffi.string(fname) class PathIter(FilenamesIter): """Iterator for pathlib.Path objects.""" def __next__(self): fname = super().__next__() return pathlib.Path(os.fsdecode(fname)) class PropertiesMap(base.NotmuchObject, collections.abc.MutableMapping): """A mutable mapping to manage properties. Both keys and values of properties are supposed to be UTF-8 strings in libnotmuch. However since the uderlying API uses bytestrings you can use either str or bytes to represent keys and all returned keys and values use :class:`BinString`. Also be aware that ``iter(this_map)`` will return duplicate keys, while the :class:`collections.abc.KeysView` returned by :meth:`keys` is a :class:`collections.abc.Set` subclass. This means the former will yield duplicate keys while the latter won't. It also means ``len(list(iter(this_map)))`` could be different than ``len(this_map.keys())``. ``len(this_map)`` will correspond with the lenght of the default iterator. Be aware that libnotmuch exposes all of this as iterators, so quite a few operations have O(n) performance instead of the usual O(1). """ Property = collections.namedtuple('Property', ['key', 'value']) _marker = object() def __init__(self, msg, ptr_name): self._msg = msg self._ptr = lambda: getattr(msg, ptr_name) @property def alive(self): if not self._msg.alive: return False try: self._ptr except errors.ObjectDestroyedError: return False else: return True def _destroy(self): pass def __iter__(self): """Return an iterator which iterates over the keys. Be aware that a single key may have multiple values associated with it, if so it will appear multiple times here. """ iter_p = capi.lib.notmuch_message_get_properties(self._ptr(), b'', 0) return PropertiesKeyIter(self, iter_p) def __len__(self): iter_p = capi.lib.notmuch_message_get_properties(self._ptr(), b'', 0) it = base.NotmuchIter( self, iter_p, fn_destroy=capi.lib.notmuch_message_properties_destroy, fn_valid=capi.lib.notmuch_message_properties_valid, fn_get=capi.lib.notmuch_message_properties_key, fn_next=capi.lib.notmuch_message_properties_move_to_next, ) return len(list(it)) def __getitem__(self, key): """Return **the first** peroperty associated with a key.""" if isinstance(key, str): key = key.encode('utf-8') value_pp = capi.ffi.new('char**') ret = capi.lib.notmuch_message_get_property(self._ptr(), key, value_pp) if ret != capi.lib.NOTMUCH_STATUS_SUCCESS: raise errors.NotmuchError(ret) if value_pp[0] == capi.ffi.NULL: raise KeyError return base.BinString.from_cffi(value_pp[0]) def keys(self): """Return a :class:`collections.abc.KeysView` for this map. Even when keys occur multiple times this is a subset of set() so will only contain them once. """ return collections.abc.KeysView({k: None for k in self}) def items(self): """Return a :class:`collections.abc.ItemsView` for this map. The ItemsView treats a ``(key, value)`` pair as unique, so dupcliate ``(key, value)`` pairs will be merged together. However duplicate keys with different values will be returned. """ items = set() props_p = capi.lib.notmuch_message_get_properties(self._ptr(), b'', 0) while capi.lib.notmuch_message_properties_valid(props_p): key = capi.lib.notmuch_message_properties_key(props_p) value = capi.lib.notmuch_message_properties_value(props_p) items.add((base.BinString.from_cffi(key), base.BinString.from_cffi(value))) capi.lib.notmuch_message_properties_move_to_next(props_p) capi.lib.notmuch_message_properties_destroy(props_p) return PropertiesItemsView(items) def values(self): """Return a :class:`collecions.abc.ValuesView` for this map. All unique property values are included in the view. """ values = set() props_p = capi.lib.notmuch_message_get_properties(self._ptr(), b'', 0) while capi.lib.notmuch_message_properties_valid(props_p): value = capi.lib.notmuch_message_properties_value(props_p) values.add(base.BinString.from_cffi(value)) capi.lib.notmuch_message_properties_move_to_next(props_p) capi.lib.notmuch_message_properties_destroy(props_p) return PropertiesValuesView(values) def __setitem__(self, key, value): """Add a key-value pair to the properties. You may prefer to use :meth:`add` for clarity since this method usually implies implicit overwriting of an existing key if it exists, while for properties this is not the case. """ self.add(key, value) def add(self, key, value): """Add a key-value pair to the properties.""" if isinstance(key, str): key = key.encode('utf-8') if isinstance(value, str): value = value.encode('utf-8') ret = capi.lib.notmuch_message_add_property(self._ptr(), key, value) if ret != capi.lib.NOTMUCH_STATUS_SUCCESS: raise errors.NotmuchError(ret) def __delitem__(self, key): """Remove all properties with this key.""" if isinstance(key, str): key = key.encode('utf-8') ret = capi.lib.notmuch_message_remove_all_properties(self._ptr(), key) if ret != capi.lib.NOTMUCH_STATUS_SUCCESS: raise errors.NotmuchError(ret) def remove(self, key, value): """Remove a key-value pair from the properties.""" if isinstance(key, str): key = key.encode('utf-8') if isinstance(value, str): value = value.encode('utf-8') ret = capi.lib.notmuch_message_remove_property(self._ptr(), key, value) if ret != capi.lib.NOTMUCH_STATUS_SUCCESS: raise errors.NotmuchError(ret) def pop(self, key, default=_marker): try: value = self[key] except KeyError: if default is self._marker: raise else: return default else: self.remove(key, value) return value def popitem(self): try: key = next(iter(self)) except StopIteration: raise KeyError value = self.pop(key) return (key, value) def clear(self): ret = capi.lib.notmuch_message_remove_all_properties(self._ptr(), capi.ffi.NULL) if ret != capi.lib.NOTMUCH_STATUS_SUCCESS: raise errors.NotmuchError(ret) def getall(self, prefix='', *, exact=False): """Return an iterator yielding all properties for a given key prefix. The returned iterator yields all peroperties which start with a given key prefix as ``(key, value)`` namedtuples. If called with ``exact=True`` then only properties which exactly match the prefix are returned, those a key longer than the prefix will not be included. :param prefix: The prefix of the key. """ if isinstance(prefix, str): prefix = prefix.encode('utf-8') props_p = capi.lib.notmuch_message_get_properties(self._ptr(), prefix, exact) return PropertiesIter(self, props_p) class PropertiesKeyIter(base.NotmuchIter): def __init__(self, parent, iter_p): super().__init__( parent, iter_p, fn_destroy=capi.lib.notmuch_message_properties_destroy, fn_valid=capi.lib.notmuch_message_properties_valid, fn_get=capi.lib.notmuch_message_properties_key, fn_next=capi.lib.notmuch_message_properties_move_to_next) def __next__(self): item = super().__next__() return base.BinString.from_cffi(item) class PropertiesIter(base.NotmuchIter): def __init__(self, parent, iter_p): super().__init__( parent, iter_p, fn_destroy=capi.lib.notmuch_message_properties_destroy, fn_valid=capi.lib.notmuch_message_properties_valid, fn_get=capi.lib.notmuch_message_properties_key, fn_next=capi.lib.notmuch_message_properties_move_to_next, ) def __next__(self): if not self._fn_valid(self._iter_p): self._destroy() raise StopIteration key = capi.lib.notmuch_message_properties_key(self._iter_p) value = capi.lib.notmuch_message_properties_value(self._iter_p) capi.lib.notmuch_message_properties_move_to_next(self._iter_p) return PropertiesMap.Property(base.BinString.from_cffi(key), base.BinString.from_cffi(value)) class PropertiesItemsView(collections.abc.Set): __slots__ = ('_items',) def __init__(self, items): self._items = items @classmethod def _from_iterable(self, it): return set(it) def __len__(self): return len(self._items) def __contains__(self, item): return item in self._items def __iter__(self): yield from self._items collections.abc.ItemsView.register(PropertiesItemsView) class PropertiesValuesView(collections.abc.Set): __slots__ = ('_values',) def __init__(self, values): self._values = values def __len__(self): return len(self._values) def __contains__(self, value): return value in self._values def __iter__(self): yield from self._values collections.abc.ValuesView.register(PropertiesValuesView) class MessageIter(base.NotmuchIter): def __init__(self, parent, msgs_p, *, db): self._db = db super().__init__(parent, msgs_p, fn_destroy=capi.lib.notmuch_messages_destroy, fn_valid=capi.lib.notmuch_messages_valid, fn_get=capi.lib.notmuch_messages_get, fn_next=capi.lib.notmuch_messages_move_to_next) def __next__(self): msg_p = super().__next__() return Message(self, msg_p, db=self._db)