# Copyright 2009-2012 10gen, Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Cursor class to iterate over Mongo query results.""" import copy from collections import deque from asyncio_mongo._bson import RE_TYPE from asyncio_mongo._bson.code import Code from asyncio_mongo._bson.son import SON from asyncio_mongo._pymongo import helpers, message, read_preferences from asyncio_mongo._pymongo.read_preferences import ReadPreference, secondary_ok_commands from asyncio_mongo._pymongo.errors import (InvalidOperation, AutoReconnect) _QUERY_OPTIONS = { "tailable_cursor": 2, "slave_okay": 4, "oplog_replay": 8, "no_timeout": 16, "await_data": 32, "exhaust": 64, "partial": 128} # This has to be an old style class due to # http://bugs.jython.org/issue1057 class _SocketManager: """Used with exhaust cursors to ensure the socket is returned. """ def __init__(self, sock, pool): self.sock = sock self.pool = pool self.__closed = False def __del__(self): self.close() def close(self): """Return this instance's socket to the connection pool. """ if not self.__closed: self.__closed = True self.pool.maybe_return_socket(self.sock) self.sock, self.pool = None, None # TODO might be cool to be able to do find().include("foo") or # find().exclude(["bar", "baz"]) or find().slice("a", 1, 2) as an # alternative to the fields specifier. class Cursor(object): """A cursor / iterator over Mongo query results. """ def __init__(self, collection, spec=None, fields=None, skip=0, limit=0, timeout=True, snapshot=False, tailable=False, sort=None, max_scan=None, as_class=None, slave_okay=False, await_data=False, partial=False, manipulate=True, read_preference=ReadPreference.PRIMARY, tag_sets=[{}], secondary_acceptable_latency_ms=None, exhaust=False, _must_use_master=False, _uuid_subtype=None, _first_batch=None, _cursor_id=None, **kwargs): """Create a new cursor. Should not be called directly by application developers - see :meth:`~pymongo.collection.Collection.find` instead. .. mongodoc:: cursors """ self.__id = _cursor_id self.__is_command_cursor = _cursor_id is not None if spec is None: spec = {} if not isinstance(spec, dict): raise TypeError("spec must be an instance of dict") if not isinstance(skip, int): raise TypeError("skip must be an instance of int") if not isinstance(limit, int): raise TypeError("limit must be an instance of int") if not isinstance(timeout, bool): raise TypeError("timeout must be an instance of bool") if not isinstance(snapshot, bool): raise TypeError("snapshot must be an instance of bool") if not isinstance(tailable, bool): raise TypeError("tailable must be an instance of bool") if not isinstance(slave_okay, bool): raise TypeError("slave_okay must be an instance of bool") if not isinstance(await_data, bool): raise TypeError("await_data must be an instance of bool") if not isinstance(partial, bool): raise TypeError("partial must be an instance of bool") if not isinstance(exhaust, bool): raise TypeError("exhaust must be an instance of bool") if fields is not None: if not fields: fields = {"_id": 1} if not isinstance(fields, dict): fields = helpers._fields_list_to_dict(fields) if as_class is None: as_class = collection.database.connection.document_class self.__collection = collection self.__spec = spec self.__fields = fields self.__skip = skip self.__limit = limit self.__batch_size = 0 # Exhaust cursor support if self.__collection.database.connection.is_mongos and exhaust: raise InvalidOperation('Exhaust cursors are ' 'not supported by mongos') if limit and exhaust: raise InvalidOperation("Can't use limit and exhaust together.") self.__exhaust = exhaust self.__exhaust_mgr = None # This is ugly. People want to be able to do cursor[5:5] and # get an empty result set (old behavior was an # exception). It's hard to do that right, though, because the # server uses limit(0) to mean 'no limit'. So we set __empty # in that case and check for it when iterating. We also unset # it anytime we change __limit. self.__empty = False self.__snapshot = snapshot self.__ordering = sort and helpers._index_document(sort) or None self.__max_scan = max_scan self.__explain = False self.__hint = None self.__as_class = as_class self.__slave_okay = slave_okay self.__manipulate = manipulate self.__read_preference = read_preference self.__tag_sets = tag_sets self.__secondary_acceptable_latency_ms = secondary_acceptable_latency_ms self.__tz_aware = collection.database.connection.tz_aware self.__must_use_master = _must_use_master self.__uuid_subtype = _uuid_subtype or collection.uuid_subtype self.__data = deque(_first_batch or []) self.__connection_id = None self.__retrieved = 0 self.__killed = False self.__query_flags = 0 if tailable: self.__query_flags |= _QUERY_OPTIONS["tailable_cursor"] if not timeout: self.__query_flags |= _QUERY_OPTIONS["no_timeout"] if tailable and await_data: self.__query_flags |= _QUERY_OPTIONS["await_data"] if exhaust: self.__query_flags |= _QUERY_OPTIONS["exhaust"] if partial: self.__query_flags |= _QUERY_OPTIONS["partial"] # this is for passing network_timeout through if it's specified # need to use kwargs as None is a legit value for network_timeout self.__kwargs = kwargs @property def collection(self): """The :class:`~pymongo.collection.Collection` that this :class:`Cursor` is iterating. .. versionadded:: 1.1 """ return self.__collection def __del__(self): if self.__id and not self.__killed: self.__die() def rewind(self): """Rewind this cursor to its unevaluated state. Reset this cursor if it has been partially or completely evaluated. Any options that are present on the cursor will remain in effect. Future iterating performed on this cursor will cause new queries to be sent to the server, even if the resultant data has already been retrieved by this cursor. """ self.__check_not_command_cursor('rewind') self.__data = deque() self.__id = None self.__connection_id = None self.__retrieved = 0 self.__killed = False return self def clone(self): """Get a clone of this cursor. Returns a new Cursor instance with options matching those that have been set on the current instance. The clone will be completely unevaluated, even if the current instance has been partially or completely evaluated. """ return self.__clone(True) def __clone(self, deepcopy=True): self.__check_not_command_cursor('clone') clone = Cursor(self.__collection) values_to_clone = ("spec", "fields", "skip", "limit", "snapshot", "ordering", "explain", "hint", "batch_size", "max_scan", "as_class", "slave_okay", "manipulate", "read_preference", "tag_sets", "secondary_acceptable_latency_ms", "must_use_master", "uuid_subtype", "query_flags", "kwargs") data = dict((k, v) for k, v in self.__dict__.items() if k.startswith('_Cursor__') and k[9:] in values_to_clone) if deepcopy: data = self.__deepcopy(data) clone.__dict__.update(data) return clone def __die(self): """Closes this cursor. """ if self.__id and not self.__killed: if self.__exhaust and self.__exhaust_mgr: # If this is an exhaust cursor and we haven't completely # exhausted the result set we *must* close the socket # to stop the server from sending more data. self.__exhaust_mgr.sock.close() else: connection = self.__collection.database.connection if self.__connection_id is not None: connection.close_cursor(self.__id, self.__connection_id) else: connection.close_cursor(self.__id) if self.__exhaust and self.__exhaust_mgr: self.__exhaust_mgr.close() self.__killed = True def close(self): """Explicitly close / kill this cursor. Required for PyPy, Jython and other Python implementations that don't use reference counting garbage collection. """ self.__die() def __query_spec(self): """Get the spec to use for a query. """ operators = {} if self.__ordering: operators["$orderby"] = self.__ordering if self.__explain: operators["$explain"] = True if self.__hint: operators["$hint"] = self.__hint if self.__snapshot: operators["$snapshot"] = True if self.__max_scan: operators["$maxScan"] = self.__max_scan # Only set $readPreference if it's something other than # PRIMARY to avoid problems with mongos versions that # don't support read preferences. if (self.__collection.database.connection.is_mongos and self.__read_preference != ReadPreference.PRIMARY): has_tags = self.__tag_sets and self.__tag_sets != [{}] # For maximum backwards compatibility, don't set $readPreference # for SECONDARY_PREFERRED unless tags are in use. Just rely on # the slaveOkay bit (set automatically if read preference is not # PRIMARY), which has the same behavior. if (self.__read_preference != ReadPreference.SECONDARY_PREFERRED or has_tags): read_pref = { 'mode': read_preferences.mongos_mode(self.__read_preference) } if has_tags: read_pref['tags'] = self.__tag_sets operators['$readPreference'] = read_pref if operators: # Make a shallow copy so we can cleanly rewind or clone. spec = self.__spec.copy() # Only commands that can be run on secondaries should have any # operators added to the spec. Command queries can be issued # by db.command or calling find_one on $cmd directly if self.collection.name == "$cmd": # Don't change commands that can't be sent to secondaries command_name = spec and list(spec.keys())[0].lower() or "" if command_name not in secondary_ok_commands: return spec elif command_name == 'mapreduce': # mapreduce shouldn't be changed if its not inline out = spec.get('out') if not isinstance(out, dict) or not out.get('inline'): return spec # White-listed commands must be wrapped in $query. if "$query" not in spec: # $query has to come first spec = SON([("$query", spec)]) if not isinstance(spec, SON): # Ensure the spec is SON. As order is important this will # ensure its set before merging in any extra operators. spec = SON(spec) spec.update(operators) return spec # Have to wrap with $query if "query" is the first key. # We can't just use $query anytime "query" is a key as # that breaks commands like count and find_and_modify. # Checking spec.keys()[0] covers the case that the spec # was passed as an instance of SON or OrderedDict. elif ("query" in self.__spec and (len(self.__spec) == 1 or list(self.__spec.keys())[0] == "query")): return SON({"$query": self.__spec}) return self.__spec def __query_options(self): """Get the query options string to use for this query. """ options = self.__query_flags if (self.__slave_okay or self.__read_preference != ReadPreference.PRIMARY ): options |= _QUERY_OPTIONS["slave_okay"] return options def __check_okay_to_chain(self): """Check if it is okay to chain more options onto this cursor. """ if self.__retrieved or self.__id is not None: raise InvalidOperation("cannot set options after executing query") def __check_not_command_cursor(self, method_name): """Check if calling a method on this cursor is valid. """ if self.__is_command_cursor: raise InvalidOperation( "cannot call %s on a command cursor" % method_name) def add_option(self, mask): """Set arbitary query flags using a bitmask. To set the tailable flag: cursor.add_option(2) """ if not isinstance(mask, int): raise TypeError("mask must be an int") self.__check_okay_to_chain() if mask & _QUERY_OPTIONS["slave_okay"]: self.__slave_okay = True if mask & _QUERY_OPTIONS["exhaust"]: if self.__limit: raise InvalidOperation("Can't use limit and exhaust together.") if self.__collection.database.connection.is_mongos: raise InvalidOperation('Exhaust cursors are ' 'not supported by mongos') self.__exhaust = True self.__query_flags |= mask return self def remove_option(self, mask): """Unset arbitrary query flags using a bitmask. To unset the tailable flag: cursor.remove_option(2) """ if not isinstance(mask, int): raise TypeError("mask must be an int") self.__check_okay_to_chain() if mask & _QUERY_OPTIONS["slave_okay"]: self.__slave_okay = False if mask & _QUERY_OPTIONS["exhaust"]: self.__exhaust = False self.__query_flags &= ~mask return self def limit(self, limit): """Limits the number of results to be returned by this cursor. Raises TypeError if limit is not an instance of int. Raises InvalidOperation if this cursor has already been used. The last `limit` applied to this cursor takes precedence. A limit of ``0`` is equivalent to no limit. :Parameters: - `limit`: the number of results to return .. mongodoc:: limit """ if not isinstance(limit, int): raise TypeError("limit must be an int") if self.__exhaust: raise InvalidOperation("Can't use limit and exhaust together.") self.__check_okay_to_chain() self.__empty = False self.__limit = limit return self def batch_size(self, batch_size): """Limits the number of documents returned in one batch. Each batch requires a round trip to the server. It can be adjusted to optimize performance and limit data transfer. .. note:: batch_size can not override MongoDB's internal limits on the amount of data it will return to the client in a single batch (i.e if you set batch size to 1,000,000,000, MongoDB will currently only return 4-16MB of results per batch). Raises :class:`TypeError` if `batch_size` is not an instance of :class:`int`. Raises :class:`ValueError` if `batch_size` is less than ``0``. Raises :class:`~pymongo.errors.InvalidOperation` if this :class:`Cursor` has already been used. The last `batch_size` applied to this cursor takes precedence. :Parameters: - `batch_size`: The size of each batch of results requested. .. versionadded:: 1.9 """ if not isinstance(batch_size, int): raise TypeError("batch_size must be an int") if batch_size < 0: raise ValueError("batch_size must be >= 0") self.__check_okay_to_chain() self.__batch_size = batch_size == 1 and 2 or batch_size return self def skip(self, skip): """Skips the first `skip` results of this cursor. Raises TypeError if skip is not an instance of int. Raises InvalidOperation if this cursor has already been used. The last `skip` applied to this cursor takes precedence. :Parameters: - `skip`: the number of results to skip """ if not isinstance(skip, int): raise TypeError("skip must be an int") self.__check_okay_to_chain() self.__skip = skip return self def __getitem__(self, index): """Get a single document or a slice of documents from this cursor. Raises :class:`~pymongo.errors.InvalidOperation` if this cursor has already been used. To get a single document use an integral index, e.g.:: >>> db.test.find()[50] An :class:`IndexError` will be raised if the index is negative or greater than the amount of documents in this cursor. Any limit previously applied to this cursor will be ignored. To get a slice of documents use a slice index, e.g.:: >>> db.test.find()[20:25] This will return this cursor with a limit of ``5`` and skip of ``20`` applied. Using a slice index will override any prior limits or skips applied to this cursor (including those applied through previous calls to this method). Raises :class:`IndexError` when the slice has a step, a negative start value, or a stop value less than or equal to the start value. :Parameters: - `index`: An integer or slice index to be applied to this cursor """ self.__check_okay_to_chain() self.__empty = False if isinstance(index, slice): if index.step is not None: raise IndexError("Cursor instances do not support slice steps") skip = 0 if index.start is not None: if index.start < 0: raise IndexError("Cursor instances do not support" "negative indices") skip = index.start if index.stop is not None: limit = index.stop - skip if limit < 0: raise IndexError("stop index must be greater than start" "index for slice %r" % index) if limit == 0: self.__empty = True else: limit = 0 self.__skip = skip self.__limit = limit return self if isinstance(index, int): if index < 0: raise IndexError("Cursor instances do not support negative" "indices") clone = self.clone() clone.skip(index + self.__skip) clone.limit(-1) # use a hard limit for doc in clone: return doc raise IndexError("no such item for Cursor instance") raise TypeError("index %r cannot be applied to Cursor " "instances" % index) def max_scan(self, max_scan): """Limit the number of documents to scan when performing the query. Raises :class:`~pymongo.errors.InvalidOperation` if this cursor has already been used. Only the last :meth:`max_scan` applied to this cursor has any effect. :Parameters: - `max_scan`: the maximum number of documents to scan .. note:: Requires server version **>= 1.5.1** .. versionadded:: 1.7 """ self.__check_okay_to_chain() self.__max_scan = max_scan return self def sort(self, key_or_list, direction=None): """Sorts this cursor's results. Takes either a single key and a direction, or a list of (key, direction) pairs. The key(s) must be an instance of ``(str, unicode)``, and the direction(s) must be one of (:data:`~pymongo.ASCENDING`, :data:`~pymongo.DESCENDING`). Raises :class:`~pymongo.errors.InvalidOperation` if this cursor has already been used. Only the last :meth:`sort` applied to this cursor has any effect. :Parameters: - `key_or_list`: a single key or a list of (key, direction) pairs specifying the keys to sort on - `direction` (optional): only used if `key_or_list` is a single key, if not given :data:`~pymongo.ASCENDING` is assumed """ self.__check_okay_to_chain() keys = helpers._index_list(key_or_list, direction) self.__ordering = helpers._index_document(keys) return self def count(self, with_limit_and_skip=False): """Get the size of the results set for this query. Returns the number of documents in the results set for this query. Does not take :meth:`limit` and :meth:`skip` into account by default - set `with_limit_and_skip` to ``True`` if that is the desired behavior. Raises :class:`~pymongo.errors.OperationFailure` on a database error. With :class:`~pymongo.mongo_replica_set_client.MongoReplicaSetClient` or :class:`~pymongo.master_slave_connection.MasterSlaveConnection`, if `read_preference` is not :attr:`pymongo.read_preferences.ReadPreference.PRIMARY` or :attr:`pymongo.read_preferences.ReadPreference.PRIMARY_PREFERRED`, or (deprecated) `slave_okay` is `True`, the count command will be sent to a secondary or slave. :Parameters: - `with_limit_and_skip` (optional): take any :meth:`limit` or :meth:`skip` that has been applied to this cursor into account when getting the count .. note:: The `with_limit_and_skip` parameter requires server version **>= 1.1.4-** .. note:: ``count`` ignores ``network_timeout``. For example, the timeout is ignored in the following code:: collection.find({}, network_timeout=1).count() .. versionadded:: 1.1.1 The `with_limit_and_skip` parameter. :meth:`~pymongo.cursor.Cursor.__len__` was deprecated in favor of calling :meth:`count` with `with_limit_and_skip` set to ``True``. """ self.__check_not_command_cursor('count') command = {"query": self.__spec, "fields": self.__fields} command['read_preference'] = self.__read_preference command['tag_sets'] = self.__tag_sets command['secondary_acceptable_latency_ms'] = ( self.__secondary_acceptable_latency_ms) command['slave_okay'] = self.__slave_okay use_master = not self.__slave_okay and not self.__read_preference command['_use_master'] = use_master if with_limit_and_skip: if self.__limit: command["limit"] = self.__limit if self.__skip: command["skip"] = self.__skip database = self.__collection.database r = database.command("count", self.__collection.name, allowable_errors=["ns missing"], uuid_subtype=self.__uuid_subtype, **command) if r.get("errmsg", "") == "ns missing": return 0 return int(r["n"]) def distinct(self, key): """Get a list of distinct values for `key` among all documents in the result set of this query. Raises :class:`TypeError` if `key` is not an instance of :class:`basestring` (:class:`str` in python 3). With :class:`~pymongo.mongo_replica_set_client.MongoReplicaSetClient` or :class:`~pymongo.master_slave_connection.MasterSlaveConnection`, if `read_preference` is not :attr:`pymongo.read_preferences.ReadPreference.PRIMARY` or (deprecated) `slave_okay` is `True` the distinct command will be sent to a secondary or slave. :Parameters: - `key`: name of key for which we want to get the distinct values .. note:: Requires server version **>= 1.1.3+** .. seealso:: :meth:`pymongo.collection.Collection.distinct` .. versionadded:: 1.2 """ self.__check_not_command_cursor('distinct') if not isinstance(key, str): raise TypeError("key must be an instance " "of %s" % (str.__name__,)) options = {"key": key} if self.__spec: options["query"] = self.__spec options['read_preference'] = self.__read_preference options['tag_sets'] = self.__tag_sets options['secondary_acceptable_latency_ms'] = ( self.__secondary_acceptable_latency_ms) options['slave_okay'] = self.__slave_okay use_master = not self.__slave_okay and not self.__read_preference options['_use_master'] = use_master database = self.__collection.database return database.command("distinct", self.__collection.name, uuid_subtype=self.__uuid_subtype, **options)["values"] def explain(self): """Returns an explain plan record for this cursor. .. mongodoc:: explain """ self.__check_not_command_cursor('explain') c = self.clone() c.__explain = True # always use a hard limit for explains if c.__limit: c.__limit = -abs(c.__limit) return next(c) def hint(self, index): """Adds a 'hint', telling Mongo the proper index to use for the query. Judicious use of hints can greatly improve query performance. When doing a query on multiple fields (at least one of which is indexed) pass the indexed field as a hint to the query. Hinting will not do anything if the corresponding index does not exist. Raises :class:`~pymongo.errors.InvalidOperation` if this cursor has already been used. `index` should be an index as passed to :meth:`~pymongo.collection.Collection.create_index` (e.g. ``[('field', ASCENDING)]``). If `index` is ``None`` any existing hints for this query are cleared. The last hint applied to this cursor takes precedence over all others. :Parameters: - `index`: index to hint on (as an index specifier) """ self.__check_okay_to_chain() if index is None: self.__hint = None return self self.__hint = helpers._index_document(index) return self def where(self, code): """Adds a $where clause to this query. The `code` argument must be an instance of :class:`basestring` (:class:`str` in python 3) or :class:`~bson.code.Code` containing a JavaScript expression. This expression will be evaluated for each document scanned. Only those documents for which the expression evaluates to *true* will be returned as results. The keyword *this* refers to the object currently being scanned. Raises :class:`TypeError` if `code` is not an instance of :class:`basestring` (:class:`str` in python 3). Raises :class:`~pymongo.errors.InvalidOperation` if this :class:`Cursor` has already been used. Only the last call to :meth:`where` applied to a :class:`Cursor` has any effect. :Parameters: - `code`: JavaScript expression to use as a filter """ self.__check_okay_to_chain() if not isinstance(code, Code): code = Code(code) self.__spec["$where"] = code return self def __send_message(self, message): """Send a query or getmore message and handles the response. If message is ``None`` this is an exhaust cursor, which reads the next result batch off the exhaust socket instead of sending getMore messages to the server. """ client = self.__collection.database.connection if message: kwargs = {"_must_use_master": self.__must_use_master} kwargs["read_preference"] = self.__read_preference kwargs["tag_sets"] = self.__tag_sets kwargs["secondary_acceptable_latency_ms"] = ( self.__secondary_acceptable_latency_ms) kwargs['exhaust'] = self.__exhaust if self.__connection_id is not None: kwargs["_connection_to_use"] = self.__connection_id kwargs.update(self.__kwargs) try: res = client._send_message_with_response(message, **kwargs) self.__connection_id, (response, sock, pool) = res if self.__exhaust: self.__exhaust_mgr = _SocketManager(sock, pool) except AutoReconnect: # Don't try to send kill cursors on another socket # or to another server. It can cause a _pinValue # assertion on some server releases if we get here # due to a socket timeout. self.__killed = True raise else: # exhaust cursor - no getMore message response = client._exhaust_next(self.__exhaust_mgr.sock) try: response = helpers._unpack_response(response, self.__id, self.__as_class, self.__tz_aware, self.__uuid_subtype) except AutoReconnect: # Don't send kill cursors to another server after a "not master" # error. It's completely pointless. self.__killed = True client.disconnect() raise self.__id = response["cursor_id"] # starting from doesn't get set on getmore's for tailable cursors if not (self.__query_flags & _QUERY_OPTIONS["tailable_cursor"]): assert response["starting_from"] == self.__retrieved, ( "Result batch started from %s, expected %s" % ( response['starting_from'], self.__retrieved)) self.__retrieved += response["number_returned"] self.__data = deque(response["data"]) if self.__limit and self.__id and self.__limit <= self.__retrieved: self.__die() # Don't wait for garbage collection to call __del__, return the # socket to the pool now. if self.__exhaust and self.__id == 0: self.__exhaust_mgr.close() def _refresh(self): """Refreshes the cursor with more data from Mongo. Returns the length of self.__data after refresh. Will exit early if self.__data is already non-empty. Raises OperationFailure when the cursor cannot be refreshed due to an error on the query. """ if len(self.__data) or self.__killed: return len(self.__data) if self.__id is None: # Query ntoreturn = self.__batch_size if self.__limit: if self.__batch_size: ntoreturn = min(self.__limit, self.__batch_size) else: ntoreturn = self.__limit self.__send_message( message.query(self.__query_options(), self.__collection.full_name, self.__skip, ntoreturn, self.__query_spec(), self.__fields, self.__uuid_subtype)) if not self.__id: self.__killed = True elif self.__id: # Get More if self.__limit: limit = self.__limit - self.__retrieved if self.__batch_size: limit = min(limit, self.__batch_size) else: limit = self.__batch_size # Exhaust cursors don't send getMore messages. if self.__exhaust: self.__send_message(None) else: self.__send_message( message.get_more(self.__collection.full_name, limit, self.__id)) else: # Cursor id is zero nothing else to return self.__killed = True return len(self.__data) @property def alive(self): """Does this cursor have the potential to return more data? This is mostly useful with `tailable cursors `_ since they will stop iterating even though they *may* return more results in the future. .. versionadded:: 1.5 """ return bool(len(self.__data) or (not self.__killed)) @property def cursor_id(self): """Returns the id of the cursor Useful if you need to manage cursor ids and want to handle killing cursors manually using :meth:`~pymongo.mongo_client.MongoClient.kill_cursors` .. versionadded:: 2.2 """ return self.__id def __iter__(self): return self def __next__(self): if self.__empty: raise StopIteration db = self.__collection.database if len(self.__data) or self._refresh(): if self.__manipulate: return db._fix_outgoing(self.__data.popleft(), self.__collection) else: return self.__data.popleft() else: raise StopIteration def __enter__(self): return self def __exit__(self, exc_type, exc_val, exc_tb): self.__die() def __copy__(self): """Support function for `copy.copy()`. .. versionadded:: 2.4 """ return self.__clone(deepcopy=False) def __deepcopy__(self, memo): """Support function for `copy.deepcopy()`. .. versionadded:: 2.4 """ return self.__clone(deepcopy=True) def __deepcopy(self, x, memo=None): """Deepcopy helper for the data dictionary or list. Regular expressions cannot be deep copied but as they are immutable we don't have to copy them when cloning. """ if not hasattr(x, 'items'): y, is_list, iterator = [], True, enumerate(x) else: y, is_list, iterator = {}, False, iter(x.items()) if memo is None: memo = {} val_id = id(x) if val_id in memo: return memo.get(val_id) memo[val_id] = y for key, value in iterator: if isinstance(value, (dict, list)) and not isinstance(value, SON): value = self.__deepcopy(value, memo) elif not isinstance(value, RE_TYPE): value = copy.deepcopy(value, memo) if is_list: y.append(value) else: if not isinstance(key, RE_TYPE): key = copy.deepcopy(key, memo) y[key] = value return y