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 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 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 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 __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
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
