1733 lines
64 KiB
Python
1733 lines
64 KiB
Python
from __future__ import absolute_import
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import copy
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import itertools
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import operator
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import pprint
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import re
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import warnings
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from bson import SON
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from bson.code import Code
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from bson import json_util
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import pymongo
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import pymongo.errors
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from pymongo.common import validate_read_preference
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from mongoengine import signals
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from mongoengine.connection import get_db
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from mongoengine.context_managers import switch_db
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from mongoengine.common import _import_class
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from mongoengine.base.common import get_document
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from mongoengine.errors import (OperationError, NotUniqueError,
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InvalidQueryError, LookUpError)
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from mongoengine.queryset import transform
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from mongoengine.queryset.field_list import QueryFieldList
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from mongoengine.queryset.visitor import Q, QNode
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__all__ = ('BaseQuerySet', 'DO_NOTHING', 'NULLIFY', 'CASCADE', 'DENY', 'PULL')
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# Delete rules
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DO_NOTHING = 0
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NULLIFY = 1
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CASCADE = 2
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DENY = 3
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PULL = 4
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RE_TYPE = type(re.compile(''))
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class BaseQuerySet(object):
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"""A set of results returned from a query. Wraps a MongoDB cursor,
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providing :class:`~mongoengine.Document` objects as the results.
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"""
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__dereference = False
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_auto_dereference = True
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def __init__(self, document, collection):
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self._document = document
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self._collection_obj = collection
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self._mongo_query = None
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self._query_obj = Q()
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self._initial_query = {}
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self._where_clause = None
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self._loaded_fields = QueryFieldList()
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self._ordering = None
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self._snapshot = False
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self._timeout = True
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self._class_check = True
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self._slave_okay = False
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self._read_preference = None
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self._iter = False
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self._scalar = []
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self._none = False
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self._as_pymongo = False
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self._as_pymongo_coerce = False
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self._search_text = None
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self._include_text_scores = False
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# If inheritance is allowed, only return instances and instances of
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# subclasses of the class being used
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if document._meta.get('allow_inheritance') is True:
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if len(self._document._subclasses) == 1:
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self._initial_query = {"_cls": self._document._subclasses[0]}
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else:
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self._initial_query = {
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"_cls": {"$in": self._document._subclasses}}
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self._loaded_fields = QueryFieldList(always_include=['_cls'])
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self._cursor_obj = None
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self._limit = None
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self._skip = None
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self._hint = -1 # Using -1 as None is a valid value for hint
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self.only_fields = []
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self._max_time_ms = None
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def __call__(self, q_obj=None, class_check=True, slave_okay=False,
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read_preference=None, **query):
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"""Filter the selected documents by calling the
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:class:`~mongoengine.queryset.QuerySet` with a query.
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:param q_obj: a :class:`~mongoengine.queryset.Q` object to be used in
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the query; the :class:`~mongoengine.queryset.QuerySet` is filtered
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multiple times with different :class:`~mongoengine.queryset.Q`
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objects, only the last one will be used
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:param class_check: If set to False bypass class name check when
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querying collection
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:param slave_okay: if True, allows this query to be run against a
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replica secondary.
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:params read_preference: if set, overrides connection-level
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read_preference from `ReplicaSetConnection`.
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:param query: Django-style query keyword arguments
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"""
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query = Q(**query)
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if q_obj:
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# make sure proper query object is passed
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if not isinstance(q_obj, QNode):
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msg = ("Not a query object: %s. "
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"Did you intend to use key=value?" % q_obj)
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raise InvalidQueryError(msg)
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query &= q_obj
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if read_preference is None:
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queryset = self.clone()
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else:
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# Use the clone provided when setting read_preference
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queryset = self.read_preference(read_preference)
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queryset._query_obj &= query
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queryset._mongo_query = None
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queryset._cursor_obj = None
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queryset._class_check = class_check
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return queryset
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def __getitem__(self, key):
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"""Support skip and limit using getitem and slicing syntax.
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"""
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queryset = self.clone()
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# Slice provided
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if isinstance(key, slice):
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try:
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queryset._cursor_obj = queryset._cursor[key]
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queryset._skip, queryset._limit = key.start, key.stop
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if key.start and key.stop:
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queryset._limit = key.stop - key.start
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except IndexError, err:
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# PyMongo raises an error if key.start == key.stop, catch it,
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# bin it, kill it.
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start = key.start or 0
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if start >= 0 and key.stop >= 0 and key.step is None:
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if start == key.stop:
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queryset.limit(0)
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queryset._skip = key.start
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queryset._limit = key.stop - start
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return queryset
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raise err
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# Allow further QuerySet modifications to be performed
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return queryset
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# Integer index provided
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elif isinstance(key, int):
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if queryset._scalar:
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return queryset._get_scalar(
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queryset._document._from_son(queryset._cursor[key],
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_auto_dereference=self._auto_dereference,
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only_fields=self.only_fields))
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if queryset._as_pymongo:
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return queryset._get_as_pymongo(queryset._cursor[key])
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return queryset._document._from_son(queryset._cursor[key],
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_auto_dereference=self._auto_dereference, only_fields=self.only_fields)
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raise AttributeError
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def __iter__(self):
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raise NotImplementedError
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def _has_data(self):
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""" Retrieves whether cursor has any data. """
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queryset = self.order_by()
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return False if queryset.first() is None else True
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def __nonzero__(self):
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""" Avoid to open all records in an if stmt in Py2. """
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return self._has_data()
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def __bool__(self):
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""" Avoid to open all records in an if stmt in Py3. """
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return self._has_data()
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# Core functions
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def all(self):
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"""Returns all documents."""
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return self.__call__()
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def filter(self, *q_objs, **query):
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"""An alias of :meth:`~mongoengine.queryset.QuerySet.__call__`
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"""
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return self.__call__(*q_objs, **query)
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def search_text(self, text, language=None, include_text_scores=False):
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"""
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Start a text search, using text indexes.
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Require: MongoDB server version 2.6+.
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:param language: The language that determines the list of stop words
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for the search and the rules for the stemmer and tokenizer.
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If not specified, the search uses the default language of the index.
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For supported languages, see `Text Search Languages <http://docs.mongodb.org/manual/reference/text-search-languages/#text-search-languages>`.
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:param include_text_scores: If True, automaticaly add a text_score attribute to Document.
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"""
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queryset = self.clone()
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if queryset._search_text:
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raise OperationError(
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"Is not possible to use search_text two times.")
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query_kwargs = SON({'$search': text})
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if language:
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query_kwargs['$language'] = language
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queryset._query_obj &= Q(__raw__={'$text': query_kwargs})
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queryset._mongo_query = None
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queryset._cursor_obj = None
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queryset._search_text = text
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queryset._include_text_scores = include_text_scores
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return queryset
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def get(self, *q_objs, **query):
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"""Retrieve the the matching object raising
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:class:`~mongoengine.queryset.MultipleObjectsReturned` or
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`DocumentName.MultipleObjectsReturned` exception if multiple results
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and :class:`~mongoengine.queryset.DoesNotExist` or
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`DocumentName.DoesNotExist` if no results are found.
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.. versionadded:: 0.3
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"""
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queryset = self.clone()
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queryset = queryset.order_by().limit(2)
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queryset = queryset.filter(*q_objs, **query)
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try:
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result = queryset.next()
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except StopIteration:
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msg = ("%s matching query does not exist."
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% queryset._document._class_name)
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raise queryset._document.DoesNotExist(msg)
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try:
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queryset.next()
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except StopIteration:
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return result
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queryset.rewind()
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message = u'%d items returned, instead of 1' % queryset.count()
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raise queryset._document.MultipleObjectsReturned(message)
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def create(self, **kwargs):
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"""Create new object. Returns the saved object instance.
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.. versionadded:: 0.4
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"""
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return self._document(**kwargs).save()
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def get_or_create(self, write_concern=None, auto_save=True,
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*q_objs, **query):
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"""Retrieve unique object or create, if it doesn't exist. Returns a
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tuple of ``(object, created)``, where ``object`` is the retrieved or
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created object and ``created`` is a boolean specifying whether a new
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object was created. Raises
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:class:`~mongoengine.queryset.MultipleObjectsReturned` or
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`DocumentName.MultipleObjectsReturned` if multiple results are found.
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A new document will be created if the document doesn't exists; a
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dictionary of default values for the new document may be provided as a
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keyword argument called :attr:`defaults`.
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.. note:: This requires two separate operations and therefore a
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race condition exists. Because there are no transactions in
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mongoDB other approaches should be investigated, to ensure you
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don't accidently duplicate data when using this method. This is
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now scheduled to be removed before 1.0
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:param write_concern: optional extra keyword arguments used if we
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have to create a new document.
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Passes any write_concern onto :meth:`~mongoengine.Document.save`
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:param auto_save: if the object is to be saved automatically if
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not found.
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.. deprecated:: 0.8
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.. versionchanged:: 0.6 - added `auto_save`
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.. versionadded:: 0.3
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"""
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msg = ("get_or_create is scheduled to be deprecated. The approach is "
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"flawed without transactions. Upserts should be preferred.")
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warnings.warn(msg, DeprecationWarning)
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defaults = query.get('defaults', {})
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if 'defaults' in query:
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del query['defaults']
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try:
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doc = self.get(*q_objs, **query)
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return doc, False
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except self._document.DoesNotExist:
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query.update(defaults)
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doc = self._document(**query)
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if auto_save:
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doc.save(write_concern=write_concern)
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return doc, True
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def first(self):
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"""Retrieve the first object matching the query.
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"""
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queryset = self.clone()
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try:
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result = queryset[0]
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except IndexError:
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result = None
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return result
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def insert(self, doc_or_docs, load_bulk=True, write_concern=None):
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"""bulk insert documents
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:param docs_or_doc: a document or list of documents to be inserted
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:param load_bulk (optional): If True returns the list of document
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instances
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:param write_concern: Extra keyword arguments are passed down to
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:meth:`~pymongo.collection.Collection.insert`
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which will be used as options for the resultant
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``getLastError`` command. For example,
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``insert(..., {w: 2, fsync: True})`` will wait until at least
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two servers have recorded the write and will force an fsync on
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each server being written to.
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By default returns document instances, set ``load_bulk`` to False to
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return just ``ObjectIds``
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.. versionadded:: 0.5
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"""
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Document = _import_class('Document')
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if write_concern is None:
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write_concern = {}
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docs = doc_or_docs
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return_one = False
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if isinstance(docs, Document) or issubclass(docs.__class__, Document):
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return_one = True
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docs = [docs]
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raw = []
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for doc in docs:
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if not isinstance(doc, self._document):
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msg = ("Some documents inserted aren't instances of %s"
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% str(self._document))
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raise OperationError(msg)
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if doc.pk and not doc._created:
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msg = "Some documents have ObjectIds use doc.update() instead"
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raise OperationError(msg)
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raw.append(doc.to_mongo())
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signals.pre_bulk_insert.send(self._document, documents=docs)
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try:
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ids = self._collection.insert(raw, **write_concern)
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except pymongo.errors.DuplicateKeyError, err:
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message = 'Could not save document (%s)'
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raise NotUniqueError(message % unicode(err))
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except pymongo.errors.OperationFailure, err:
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message = 'Could not save document (%s)'
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if re.match('^E1100[01] duplicate key', unicode(err)):
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# E11000 - duplicate key error index
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# E11001 - duplicate key on update
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message = u'Tried to save duplicate unique keys (%s)'
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raise NotUniqueError(message % unicode(err))
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raise OperationError(message % unicode(err))
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if not load_bulk:
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signals.post_bulk_insert.send(
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self._document, documents=docs, loaded=False)
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return return_one and ids[0] or ids
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documents = self.in_bulk(ids)
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results = []
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for obj_id in ids:
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results.append(documents.get(obj_id))
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signals.post_bulk_insert.send(
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self._document, documents=results, loaded=True)
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return return_one and results[0] or results
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def count(self, with_limit_and_skip=True):
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"""Count the selected elements in the query.
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:param with_limit_and_skip (optional): take any :meth:`limit` or
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:meth:`skip` that has been applied to this cursor into account when
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getting the count
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"""
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if self._limit == 0 and with_limit_and_skip or self._none:
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return 0
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return self._cursor.count(with_limit_and_skip=with_limit_and_skip)
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def delete(self, write_concern=None, _from_doc_delete=False):
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"""Delete the documents matched by the query.
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:param write_concern: Extra keyword arguments are passed down which
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will be used as options for the resultant
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``getLastError`` command. For example,
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``save(..., write_concern={w: 2, fsync: True}, ...)`` will
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wait until at least two servers have recorded the write and
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will force an fsync on the primary server.
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:param _from_doc_delete: True when called from document delete therefore
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signals will have been triggered so don't loop.
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:returns number of deleted documents
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"""
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queryset = self.clone()
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doc = queryset._document
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if write_concern is None:
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write_concern = {}
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# Handle deletes where skips or limits have been applied or
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# there is an untriggered delete signal
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has_delete_signal = signals.signals_available and (
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signals.pre_delete.has_receivers_for(self._document) or
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signals.post_delete.has_receivers_for(self._document))
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call_document_delete = (queryset._skip or queryset._limit or
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has_delete_signal) and not _from_doc_delete
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if call_document_delete:
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cnt = 0
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for doc in queryset:
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doc.delete(write_concern=write_concern)
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cnt += 1
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return cnt
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delete_rules = doc._meta.get('delete_rules') or {}
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# Check for DENY rules before actually deleting/nullifying any other
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# references
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for rule_entry in delete_rules:
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document_cls, field_name = rule_entry
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rule = doc._meta['delete_rules'][rule_entry]
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if rule == DENY and document_cls.objects(
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**{field_name + '__in': self}).count() > 0:
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msg = ("Could not delete document (%s.%s refers to it)"
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% (document_cls.__name__, field_name))
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raise OperationError(msg)
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for rule_entry in delete_rules:
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document_cls, field_name = rule_entry
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rule = doc._meta['delete_rules'][rule_entry]
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if rule == CASCADE:
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ref_q = document_cls.objects(**{field_name + '__in': self})
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ref_q_count = ref_q.count()
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if (doc != document_cls and ref_q_count > 0
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or (doc == document_cls and ref_q_count > 0)):
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ref_q.delete(write_concern=write_concern)
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elif rule == NULLIFY:
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document_cls.objects(**{field_name + '__in': self}).update(
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write_concern=write_concern, **{'unset__%s' % field_name: 1})
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elif rule == PULL:
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document_cls.objects(**{field_name + '__in': self}).update(
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write_concern=write_concern,
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**{'pull_all__%s' % field_name: self})
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result = queryset._collection.remove(queryset._query, write_concern=write_concern)
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return result["n"]
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|
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def update(self, upsert=False, multi=True, write_concern=None,
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full_result=False, **update):
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"""Perform an atomic update on the fields matched by the query.
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:param upsert: Any existing document with that "_id" is overwritten.
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:param multi: Update multiple documents.
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:param write_concern: Extra keyword arguments are passed down which
|
|
will be used as options for the resultant
|
|
``getLastError`` command. For example,
|
|
``save(..., write_concern={w: 2, fsync: True}, ...)`` will
|
|
wait until at least two servers have recorded the write and
|
|
will force an fsync on the primary server.
|
|
:param full_result: Return the full result rather than just the number
|
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updated.
|
|
:param update: Django-style update keyword arguments
|
|
|
|
.. versionadded:: 0.2
|
|
"""
|
|
if not update and not upsert:
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raise OperationError("No update parameters, would remove data")
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|
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if write_concern is None:
|
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write_concern = {}
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|
|
queryset = self.clone()
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query = queryset._query
|
|
update = transform.update(queryset._document, **update)
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|
|
# If doing an atomic upsert on an inheritable class
|
|
# then ensure we add _cls to the update operation
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if upsert and '_cls' in query:
|
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if '$set' in update:
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update["$set"]["_cls"] = queryset._document._class_name
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else:
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update["$set"] = {"_cls": queryset._document._class_name}
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try:
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result = queryset._collection.update(query, update, multi=multi,
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upsert=upsert, **write_concern)
|
|
if full_result:
|
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return result
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|
elif result:
|
|
return result['n']
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except pymongo.errors.DuplicateKeyError, err:
|
|
raise NotUniqueError(u'Update failed (%s)' % unicode(err))
|
|
except pymongo.errors.OperationFailure, err:
|
|
if unicode(err) == u'multi not coded yet':
|
|
message = u'update() method requires MongoDB 1.1.3+'
|
|
raise OperationError(message)
|
|
raise OperationError(u'Update failed (%s)' % unicode(err))
|
|
|
|
def update_one(self, upsert=False, write_concern=None, **update):
|
|
"""Perform an atomic update on first field matched by the query.
|
|
|
|
:param upsert: Any existing document with that "_id" is overwritten.
|
|
:param write_concern: Extra keyword arguments are passed down which
|
|
will be used as options for the resultant
|
|
``getLastError`` command. For example,
|
|
``save(..., write_concern={w: 2, fsync: True}, ...)`` will
|
|
wait until at least two servers have recorded the write and
|
|
will force an fsync on the primary server.
|
|
:param update: Django-style update keyword arguments
|
|
|
|
.. versionadded:: 0.2
|
|
"""
|
|
return self.update(
|
|
upsert=upsert, multi=False, write_concern=write_concern, **update)
|
|
|
|
def modify(self, upsert=False, full_response=False, remove=False, new=False, **update):
|
|
"""Update and return the updated document.
|
|
|
|
Returns either the document before or after modification based on `new`
|
|
parameter. If no documents match the query and `upsert` is false,
|
|
returns ``None``. If upserting and `new` is false, returns ``None``.
|
|
|
|
If the full_response parameter is ``True``, the return value will be
|
|
the entire response object from the server, including the 'ok' and
|
|
'lastErrorObject' fields, rather than just the modified document.
|
|
This is useful mainly because the 'lastErrorObject' document holds
|
|
information about the command's execution.
|
|
|
|
:param upsert: insert if document doesn't exist (default ``False``)
|
|
:param full_response: return the entire response object from the
|
|
server (default ``False``)
|
|
:param remove: remove rather than updating (default ``False``)
|
|
:param new: return updated rather than original document
|
|
(default ``False``)
|
|
:param update: Django-style update keyword arguments
|
|
|
|
.. versionadded:: 0.9
|
|
"""
|
|
|
|
if remove and new:
|
|
raise OperationError("Conflicting parameters: remove and new")
|
|
|
|
if not update and not upsert and not remove:
|
|
raise OperationError(
|
|
"No update parameters, must either update or remove")
|
|
|
|
queryset = self.clone()
|
|
query = queryset._query
|
|
update = transform.update(queryset._document, **update)
|
|
sort = queryset._ordering
|
|
|
|
try:
|
|
result = queryset._collection.find_and_modify(
|
|
query, update, upsert=upsert, sort=sort, remove=remove, new=new,
|
|
full_response=full_response, **self._cursor_args)
|
|
except pymongo.errors.DuplicateKeyError, err:
|
|
raise NotUniqueError(u"Update failed (%s)" % err)
|
|
except pymongo.errors.OperationFailure, err:
|
|
raise OperationError(u"Update failed (%s)" % err)
|
|
|
|
if full_response:
|
|
if result["value"] is not None:
|
|
result["value"] = self._document._from_son(result["value"], only_fields=self.only_fields)
|
|
else:
|
|
if result is not None:
|
|
result = self._document._from_son(result, only_fields=self.only_fields)
|
|
|
|
return result
|
|
|
|
def with_id(self, object_id):
|
|
"""Retrieve the object matching the id provided. Uses `object_id` only
|
|
and raises InvalidQueryError if a filter has been applied. Returns
|
|
`None` if no document exists with that id.
|
|
|
|
:param object_id: the value for the id of the document to look up
|
|
|
|
.. versionchanged:: 0.6 Raises InvalidQueryError if filter has been set
|
|
"""
|
|
queryset = self.clone()
|
|
if not queryset._query_obj.empty:
|
|
msg = "Cannot use a filter whilst using `with_id`"
|
|
raise InvalidQueryError(msg)
|
|
return queryset.filter(pk=object_id).first()
|
|
|
|
def in_bulk(self, object_ids):
|
|
"""Retrieve a set of documents by their ids.
|
|
|
|
:param object_ids: a list or tuple of ``ObjectId``\ s
|
|
:rtype: dict of ObjectIds as keys and collection-specific
|
|
Document subclasses as values.
|
|
|
|
.. versionadded:: 0.3
|
|
"""
|
|
doc_map = {}
|
|
|
|
docs = self._collection.find({'_id': {'$in': object_ids}},
|
|
**self._cursor_args)
|
|
if self._scalar:
|
|
for doc in docs:
|
|
doc_map[doc['_id']] = self._get_scalar(
|
|
self._document._from_son(doc, only_fields=self.only_fields))
|
|
elif self._as_pymongo:
|
|
for doc in docs:
|
|
doc_map[doc['_id']] = self._get_as_pymongo(doc)
|
|
else:
|
|
for doc in docs:
|
|
doc_map[doc['_id']] = self._document._from_son(doc, only_fields=self.only_fields)
|
|
|
|
return doc_map
|
|
|
|
def none(self):
|
|
"""Helper that just returns a list"""
|
|
queryset = self.clone()
|
|
queryset._none = True
|
|
return queryset
|
|
|
|
def no_sub_classes(self):
|
|
"""
|
|
Only return instances of this document and not any inherited documents
|
|
"""
|
|
if self._document._meta.get('allow_inheritance') is True:
|
|
self._initial_query = {"_cls": self._document._class_name}
|
|
|
|
return self
|
|
|
|
def using(self, alias):
|
|
"""This method is for controlling which database the QuerySet will be evaluated against if you are using more than one database.
|
|
|
|
:param alias: The database alias
|
|
|
|
.. versionadded:: 0.9
|
|
"""
|
|
|
|
with switch_db(self._document, alias) as cls:
|
|
collection = cls._get_collection()
|
|
|
|
return self.clone_into(self.__class__(self._document, collection))
|
|
|
|
def clone(self):
|
|
"""Creates a copy of the current
|
|
:class:`~mongoengine.queryset.QuerySet`
|
|
|
|
.. versionadded:: 0.5
|
|
"""
|
|
return self.clone_into(self.__class__(self._document, self._collection_obj))
|
|
|
|
def clone_into(self, cls):
|
|
"""Creates a copy of the current
|
|
:class:`~mongoengine.queryset.base.BaseQuerySet` into another child class
|
|
"""
|
|
if not isinstance(cls, BaseQuerySet):
|
|
raise OperationError(
|
|
'%s is not a subclass of BaseQuerySet' % cls.__name__)
|
|
|
|
copy_props = ('_mongo_query', '_initial_query', '_none', '_query_obj',
|
|
'_where_clause', '_loaded_fields', '_ordering', '_snapshot',
|
|
'_timeout', '_class_check', '_slave_okay', '_read_preference',
|
|
'_iter', '_scalar', '_as_pymongo', '_as_pymongo_coerce',
|
|
'_limit', '_skip', '_hint', '_auto_dereference',
|
|
'_search_text', '_include_text_scores', 'only_fields', '_max_time_ms')
|
|
|
|
for prop in copy_props:
|
|
val = getattr(self, prop)
|
|
setattr(cls, prop, copy.copy(val))
|
|
|
|
if self._cursor_obj:
|
|
cls._cursor_obj = self._cursor_obj.clone()
|
|
|
|
return cls
|
|
|
|
def select_related(self, max_depth=1):
|
|
"""Handles dereferencing of :class:`~bson.dbref.DBRef` objects or
|
|
:class:`~bson.object_id.ObjectId` a maximum depth in order to cut down
|
|
the number queries to mongodb.
|
|
|
|
.. versionadded:: 0.5
|
|
"""
|
|
# Make select related work the same for querysets
|
|
max_depth += 1
|
|
queryset = self.clone()
|
|
return queryset._dereference(queryset, max_depth=max_depth)
|
|
|
|
def limit(self, n):
|
|
"""Limit the number of returned documents to `n`. This may also be
|
|
achieved using array-slicing syntax (e.g. ``User.objects[:5]``).
|
|
|
|
:param n: the maximum number of objects to return
|
|
"""
|
|
queryset = self.clone()
|
|
if n == 0:
|
|
queryset._cursor.limit(1)
|
|
else:
|
|
queryset._cursor.limit(n)
|
|
queryset._limit = n
|
|
# Return self to allow chaining
|
|
return queryset
|
|
|
|
def skip(self, n):
|
|
"""Skip `n` documents before returning the results. This may also be
|
|
achieved using array-slicing syntax (e.g. ``User.objects[5:]``).
|
|
|
|
:param n: the number of objects to skip before returning results
|
|
"""
|
|
queryset = self.clone()
|
|
queryset._cursor.skip(n)
|
|
queryset._skip = n
|
|
return queryset
|
|
|
|
def hint(self, index=None):
|
|
"""Added 'hint' support, 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.
|
|
The last hint applied to this cursor takes precedence over all others.
|
|
|
|
.. versionadded:: 0.5
|
|
"""
|
|
queryset = self.clone()
|
|
queryset._cursor.hint(index)
|
|
queryset._hint = index
|
|
return queryset
|
|
|
|
def distinct(self, field):
|
|
"""Return a list of distinct values for a given field.
|
|
|
|
:param field: the field to select distinct values from
|
|
|
|
.. note:: This is a command and won't take ordering or limit into
|
|
account.
|
|
|
|
.. versionadded:: 0.4
|
|
.. versionchanged:: 0.5 - Fixed handling references
|
|
.. versionchanged:: 0.6 - Improved db_field refrence handling
|
|
"""
|
|
queryset = self.clone()
|
|
try:
|
|
field = self._fields_to_dbfields([field]).pop()
|
|
finally:
|
|
distinct = self._dereference(queryset._cursor.distinct(field), 1,
|
|
name=field, instance=self._document)
|
|
|
|
# We may need to cast to the correct type eg.
|
|
# ListField(EmbeddedDocumentField)
|
|
doc_field = getattr(
|
|
self._document._fields.get(field), "field", None)
|
|
instance = getattr(doc_field, "document_type", False)
|
|
EmbeddedDocumentField = _import_class('EmbeddedDocumentField')
|
|
GenericEmbeddedDocumentField = _import_class(
|
|
'GenericEmbeddedDocumentField')
|
|
if instance and isinstance(doc_field, (EmbeddedDocumentField,
|
|
GenericEmbeddedDocumentField)):
|
|
distinct = [instance(**doc) for doc in distinct]
|
|
return distinct
|
|
|
|
def only(self, *fields):
|
|
"""Load only a subset of this document's fields. ::
|
|
|
|
post = BlogPost.objects(...).only("title", "author.name")
|
|
|
|
.. note :: `only()` is chainable and will perform a union ::
|
|
So with the following it will fetch both: `title` and `author.name`::
|
|
|
|
post = BlogPost.objects.only("title").only("author.name")
|
|
|
|
:func:`~mongoengine.queryset.QuerySet.all_fields` will reset any
|
|
field filters.
|
|
|
|
:param fields: fields to include
|
|
|
|
.. versionadded:: 0.3
|
|
.. versionchanged:: 0.5 - Added subfield support
|
|
"""
|
|
fields = dict([(f, QueryFieldList.ONLY) for f in fields])
|
|
self.only_fields = fields.keys()
|
|
return self.fields(True, **fields)
|
|
|
|
def exclude(self, *fields):
|
|
"""Opposite to .only(), exclude some document's fields. ::
|
|
|
|
post = BlogPost.objects(...).exclude("comments")
|
|
|
|
.. note :: `exclude()` is chainable and will perform a union ::
|
|
So with the following it will exclude both: `title` and `author.name`::
|
|
|
|
post = BlogPost.objects.exclude("title").exclude("author.name")
|
|
|
|
:func:`~mongoengine.queryset.QuerySet.all_fields` will reset any
|
|
field filters.
|
|
|
|
:param fields: fields to exclude
|
|
|
|
.. versionadded:: 0.5
|
|
"""
|
|
fields = dict([(f, QueryFieldList.EXCLUDE) for f in fields])
|
|
return self.fields(**fields)
|
|
|
|
def fields(self, _only_called=False, **kwargs):
|
|
"""Manipulate how you load this document's fields. Used by `.only()`
|
|
and `.exclude()` to manipulate which fields to retrieve. Fields also
|
|
allows for a greater level of control for example:
|
|
|
|
Retrieving a Subrange of Array Elements:
|
|
|
|
You can use the $slice operator to retrieve a subrange of elements in
|
|
an array. For example to get the first 5 comments::
|
|
|
|
post = BlogPost.objects(...).fields(slice__comments=5)
|
|
|
|
:param kwargs: A dictionary identifying what to include
|
|
|
|
.. versionadded:: 0.5
|
|
"""
|
|
|
|
# Check for an operator and transform to mongo-style if there is
|
|
operators = ["slice"]
|
|
cleaned_fields = []
|
|
for key, value in kwargs.items():
|
|
parts = key.split('__')
|
|
op = None
|
|
if parts[0] in operators:
|
|
op = parts.pop(0)
|
|
value = {'$' + op: value}
|
|
key = '.'.join(parts)
|
|
cleaned_fields.append((key, value))
|
|
|
|
fields = sorted(cleaned_fields, key=operator.itemgetter(1))
|
|
queryset = self.clone()
|
|
for value, group in itertools.groupby(fields, lambda x: x[1]):
|
|
fields = [field for field, value in group]
|
|
fields = queryset._fields_to_dbfields(fields)
|
|
queryset._loaded_fields += QueryFieldList(
|
|
fields, value=value, _only_called=_only_called)
|
|
|
|
return queryset
|
|
|
|
def all_fields(self):
|
|
"""Include all fields. Reset all previously calls of .only() or
|
|
.exclude(). ::
|
|
|
|
post = BlogPost.objects.exclude("comments").all_fields()
|
|
|
|
.. versionadded:: 0.5
|
|
"""
|
|
queryset = self.clone()
|
|
queryset._loaded_fields = QueryFieldList(
|
|
always_include=queryset._loaded_fields.always_include)
|
|
return queryset
|
|
|
|
def order_by(self, *keys):
|
|
"""Order the :class:`~mongoengine.queryset.QuerySet` by the keys. The
|
|
order may be specified by prepending each of the keys by a + or a -.
|
|
Ascending order is assumed.
|
|
|
|
:param keys: fields to order the query results by; keys may be
|
|
prefixed with **+** or **-** to determine the ordering direction
|
|
"""
|
|
queryset = self.clone()
|
|
queryset._ordering = queryset._get_order_by(keys)
|
|
return queryset
|
|
|
|
def explain(self, format=False):
|
|
"""Return an explain plan record for the
|
|
:class:`~mongoengine.queryset.QuerySet`\ 's cursor.
|
|
|
|
:param format: format the plan before returning it
|
|
"""
|
|
plan = self._cursor.explain()
|
|
if format:
|
|
plan = pprint.pformat(plan)
|
|
return plan
|
|
|
|
def snapshot(self, enabled):
|
|
"""Enable or disable snapshot mode when querying.
|
|
|
|
:param enabled: whether or not snapshot mode is enabled
|
|
|
|
..versionchanged:: 0.5 - made chainable
|
|
"""
|
|
queryset = self.clone()
|
|
queryset._snapshot = enabled
|
|
return queryset
|
|
|
|
def timeout(self, enabled):
|
|
"""Enable or disable the default mongod timeout when querying.
|
|
|
|
:param enabled: whether or not the timeout is used
|
|
|
|
..versionchanged:: 0.5 - made chainable
|
|
"""
|
|
queryset = self.clone()
|
|
queryset._timeout = enabled
|
|
return queryset
|
|
|
|
def slave_okay(self, enabled):
|
|
"""Enable or disable the slave_okay when querying.
|
|
|
|
:param enabled: whether or not the slave_okay is enabled
|
|
"""
|
|
queryset = self.clone()
|
|
queryset._slave_okay = enabled
|
|
return queryset
|
|
|
|
def read_preference(self, read_preference):
|
|
"""Change the read_preference when querying.
|
|
|
|
:param read_preference: override ReplicaSetConnection-level
|
|
preference.
|
|
"""
|
|
validate_read_preference('read_preference', read_preference)
|
|
queryset = self.clone()
|
|
queryset._read_preference = read_preference
|
|
return queryset
|
|
|
|
def scalar(self, *fields):
|
|
"""Instead of returning Document instances, return either a specific
|
|
value or a tuple of values in order.
|
|
|
|
Can be used along with
|
|
:func:`~mongoengine.queryset.QuerySet.no_dereference` to turn off
|
|
dereferencing.
|
|
|
|
.. note:: This effects all results and can be unset by calling
|
|
``scalar`` without arguments. Calls ``only`` automatically.
|
|
|
|
:param fields: One or more fields to return instead of a Document.
|
|
"""
|
|
queryset = self.clone()
|
|
queryset._scalar = list(fields)
|
|
|
|
if fields:
|
|
queryset = queryset.only(*fields)
|
|
else:
|
|
queryset = queryset.all_fields()
|
|
|
|
return queryset
|
|
|
|
def values_list(self, *fields):
|
|
"""An alias for scalar"""
|
|
return self.scalar(*fields)
|
|
|
|
def as_pymongo(self, coerce_types=False):
|
|
"""Instead of returning Document instances, return raw values from
|
|
pymongo.
|
|
|
|
:param coerce_type: Field types (if applicable) would be use to
|
|
coerce types.
|
|
"""
|
|
queryset = self.clone()
|
|
queryset._as_pymongo = True
|
|
queryset._as_pymongo_coerce = coerce_types
|
|
return queryset
|
|
|
|
def max_time_ms(self, ms):
|
|
"""Wait `ms` milliseconds before killing the query on the server
|
|
|
|
:param ms: the number of milliseconds before killing the query on the server
|
|
"""
|
|
return self._chainable_method("max_time_ms", ms)
|
|
|
|
# JSON Helpers
|
|
|
|
def to_json(self, *args, **kwargs):
|
|
"""Converts a queryset to JSON"""
|
|
return json_util.dumps(self.as_pymongo(), *args, **kwargs)
|
|
|
|
def from_json(self, json_data):
|
|
"""Converts json data to unsaved objects"""
|
|
son_data = json_util.loads(json_data)
|
|
return [self._document._from_son(data, only_fields=self.only_fields) for data in son_data]
|
|
|
|
def aggregate(self, *pipeline, **kwargs):
|
|
"""
|
|
Perform a aggreggate function based in your queryset params
|
|
:param pipeline: list of agreggation commands,
|
|
see: http://docs.mongodb.org/manual/core/aggregation-pipeline/
|
|
|
|
.. versionadded:: 0.9
|
|
"""
|
|
initial_pipeline = []
|
|
|
|
if self._query:
|
|
initial_pipeline.append({'$match': self._query})
|
|
|
|
if self._ordering:
|
|
initial_pipeline.append({'$sort': dict(self._ordering)})
|
|
|
|
if self._limit is not None:
|
|
initial_pipeline.append({'$limit': self._limit})
|
|
|
|
if self._skip is not None:
|
|
initial_pipeline.append({'$skip': self._skip})
|
|
|
|
pipeline = initial_pipeline + list(pipeline)
|
|
|
|
return self._collection.aggregate(pipeline, cursor={}, **kwargs)
|
|
|
|
# JS functionality
|
|
def map_reduce(self, map_f, reduce_f, output, finalize_f=None, limit=None,
|
|
scope=None):
|
|
"""Perform a map/reduce query using the current query spec
|
|
and ordering. While ``map_reduce`` respects ``QuerySet`` chaining,
|
|
it must be the last call made, as it does not return a maleable
|
|
``QuerySet``.
|
|
|
|
See the :meth:`~mongoengine.tests.QuerySetTest.test_map_reduce`
|
|
and :meth:`~mongoengine.tests.QuerySetTest.test_map_advanced`
|
|
tests in ``tests.queryset.QuerySetTest`` for usage examples.
|
|
|
|
:param map_f: map function, as :class:`~bson.code.Code` or string
|
|
:param reduce_f: reduce function, as
|
|
:class:`~bson.code.Code` or string
|
|
:param output: output collection name, if set to 'inline' will try to
|
|
use :class:`~pymongo.collection.Collection.inline_map_reduce`
|
|
This can also be a dictionary containing output options
|
|
see: http://docs.mongodb.org/manual/reference/command/mapReduce/#dbcmd.mapReduce
|
|
:param finalize_f: finalize function, an optional function that
|
|
performs any post-reduction processing.
|
|
:param scope: values to insert into map/reduce global scope. Optional.
|
|
:param limit: number of objects from current query to provide
|
|
to map/reduce method
|
|
|
|
Returns an iterator yielding
|
|
:class:`~mongoengine.document.MapReduceDocument`.
|
|
|
|
.. note::
|
|
|
|
Map/Reduce changed in server version **>= 1.7.4**. The PyMongo
|
|
:meth:`~pymongo.collection.Collection.map_reduce` helper requires
|
|
PyMongo version **>= 1.11**.
|
|
|
|
.. versionchanged:: 0.5
|
|
- removed ``keep_temp`` keyword argument, which was only relevant
|
|
for MongoDB server versions older than 1.7.4
|
|
|
|
.. versionadded:: 0.3
|
|
"""
|
|
queryset = self.clone()
|
|
|
|
MapReduceDocument = _import_class('MapReduceDocument')
|
|
|
|
if not hasattr(self._collection, "map_reduce"):
|
|
raise NotImplementedError("Requires MongoDB >= 1.7.1")
|
|
|
|
map_f_scope = {}
|
|
if isinstance(map_f, Code):
|
|
map_f_scope = map_f.scope
|
|
map_f = unicode(map_f)
|
|
map_f = Code(queryset._sub_js_fields(map_f), map_f_scope)
|
|
|
|
reduce_f_scope = {}
|
|
if isinstance(reduce_f, Code):
|
|
reduce_f_scope = reduce_f.scope
|
|
reduce_f = unicode(reduce_f)
|
|
reduce_f_code = queryset._sub_js_fields(reduce_f)
|
|
reduce_f = Code(reduce_f_code, reduce_f_scope)
|
|
|
|
mr_args = {'query': queryset._query}
|
|
|
|
if finalize_f:
|
|
finalize_f_scope = {}
|
|
if isinstance(finalize_f, Code):
|
|
finalize_f_scope = finalize_f.scope
|
|
finalize_f = unicode(finalize_f)
|
|
finalize_f_code = queryset._sub_js_fields(finalize_f)
|
|
finalize_f = Code(finalize_f_code, finalize_f_scope)
|
|
mr_args['finalize'] = finalize_f
|
|
|
|
if scope:
|
|
mr_args['scope'] = scope
|
|
|
|
if limit:
|
|
mr_args['limit'] = limit
|
|
|
|
if output == 'inline' and not queryset._ordering:
|
|
map_reduce_function = 'inline_map_reduce'
|
|
else:
|
|
map_reduce_function = 'map_reduce'
|
|
|
|
if isinstance(output, basestring):
|
|
mr_args['out'] = output
|
|
|
|
elif isinstance(output, dict):
|
|
ordered_output = []
|
|
|
|
for part in ('replace', 'merge', 'reduce'):
|
|
value = output.get(part)
|
|
if value:
|
|
ordered_output.append((part, value))
|
|
break
|
|
|
|
else:
|
|
raise OperationError("actionData not specified for output")
|
|
|
|
db_alias = output.get('db_alias')
|
|
remaing_args = ['db', 'sharded', 'nonAtomic']
|
|
|
|
if db_alias:
|
|
ordered_output.append(('db', get_db(db_alias).name))
|
|
del remaing_args[0]
|
|
|
|
for part in remaing_args:
|
|
value = output.get(part)
|
|
if value:
|
|
ordered_output.append((part, value))
|
|
|
|
mr_args['out'] = SON(ordered_output)
|
|
|
|
results = getattr(queryset._collection, map_reduce_function)(
|
|
map_f, reduce_f, **mr_args)
|
|
|
|
if map_reduce_function == 'map_reduce':
|
|
results = results.find()
|
|
|
|
if queryset._ordering:
|
|
results = results.sort(queryset._ordering)
|
|
|
|
for doc in results:
|
|
yield MapReduceDocument(queryset._document, queryset._collection,
|
|
doc['_id'], doc['value'])
|
|
|
|
def exec_js(self, code, *fields, **options):
|
|
"""Execute a Javascript function on the server. A list of fields may be
|
|
provided, which will be translated to their correct names and supplied
|
|
as the arguments to the function. A few extra variables are added to
|
|
the function's scope: ``collection``, which is the name of the
|
|
collection in use; ``query``, which is an object representing the
|
|
current query; and ``options``, which is an object containing any
|
|
options specified as keyword arguments.
|
|
|
|
As fields in MongoEngine may use different names in the database (set
|
|
using the :attr:`db_field` keyword argument to a :class:`Field`
|
|
constructor), a mechanism exists for replacing MongoEngine field names
|
|
with the database field names in Javascript code. When accessing a
|
|
field, use square-bracket notation, and prefix the MongoEngine field
|
|
name with a tilde (~).
|
|
|
|
:param code: a string of Javascript code to execute
|
|
:param fields: fields that you will be using in your function, which
|
|
will be passed in to your function as arguments
|
|
:param options: options that you want available to the function
|
|
(accessed in Javascript through the ``options`` object)
|
|
"""
|
|
queryset = self.clone()
|
|
|
|
code = queryset._sub_js_fields(code)
|
|
|
|
fields = [queryset._document._translate_field_name(f) for f in fields]
|
|
collection = queryset._document._get_collection_name()
|
|
|
|
scope = {
|
|
'collection': collection,
|
|
'options': options or {},
|
|
}
|
|
|
|
query = queryset._query
|
|
if queryset._where_clause:
|
|
query['$where'] = queryset._where_clause
|
|
|
|
scope['query'] = query
|
|
code = Code(code, scope=scope)
|
|
|
|
db = queryset._document._get_db()
|
|
return db.eval(code, *fields)
|
|
|
|
def where(self, where_clause):
|
|
"""Filter ``QuerySet`` results with a ``$where`` clause (a Javascript
|
|
expression). Performs automatic field name substitution like
|
|
:meth:`mongoengine.queryset.Queryset.exec_js`.
|
|
|
|
.. note:: When using this mode of query, the database will call your
|
|
function, or evaluate your predicate clause, for each object
|
|
in the collection.
|
|
|
|
.. versionadded:: 0.5
|
|
"""
|
|
queryset = self.clone()
|
|
where_clause = queryset._sub_js_fields(where_clause)
|
|
queryset._where_clause = where_clause
|
|
return queryset
|
|
|
|
def sum(self, field):
|
|
"""Sum over the values of the specified field.
|
|
|
|
:param field: the field to sum over; use dot-notation to refer to
|
|
embedded document fields
|
|
|
|
.. versionchanged:: 0.5 - updated to map_reduce as db.eval doesnt work
|
|
with sharding.
|
|
"""
|
|
map_func = """
|
|
function() {
|
|
var path = '{{~%(field)s}}'.split('.'),
|
|
field = this;
|
|
|
|
for (p in path) {
|
|
if (typeof field != 'undefined')
|
|
field = field[path[p]];
|
|
else
|
|
break;
|
|
}
|
|
|
|
if (field && field.constructor == Array) {
|
|
field.forEach(function(item) {
|
|
emit(1, item||0);
|
|
});
|
|
} else if (typeof field != 'undefined') {
|
|
emit(1, field||0);
|
|
}
|
|
}
|
|
""" % dict(field=field)
|
|
|
|
reduce_func = Code("""
|
|
function(key, values) {
|
|
var sum = 0;
|
|
for (var i in values) {
|
|
sum += values[i];
|
|
}
|
|
return sum;
|
|
}
|
|
""")
|
|
|
|
for result in self.map_reduce(map_func, reduce_func, output='inline'):
|
|
return result.value
|
|
else:
|
|
return 0
|
|
|
|
def average(self, field):
|
|
"""Average over the values of the specified field.
|
|
|
|
:param field: the field to average over; use dot-notation to refer to
|
|
embedded document fields
|
|
|
|
.. versionchanged:: 0.5 - updated to map_reduce as db.eval doesnt work
|
|
with sharding.
|
|
"""
|
|
map_func = """
|
|
function() {
|
|
var path = '{{~%(field)s}}'.split('.'),
|
|
field = this;
|
|
|
|
for (p in path) {
|
|
if (typeof field != 'undefined')
|
|
field = field[path[p]];
|
|
else
|
|
break;
|
|
}
|
|
|
|
if (field && field.constructor == Array) {
|
|
field.forEach(function(item) {
|
|
emit(1, {t: item||0, c: 1});
|
|
});
|
|
} else if (typeof field != 'undefined') {
|
|
emit(1, {t: field||0, c: 1});
|
|
}
|
|
}
|
|
""" % dict(field=field)
|
|
|
|
reduce_func = Code("""
|
|
function(key, values) {
|
|
var out = {t: 0, c: 0};
|
|
for (var i in values) {
|
|
var value = values[i];
|
|
out.t += value.t;
|
|
out.c += value.c;
|
|
}
|
|
return out;
|
|
}
|
|
""")
|
|
|
|
finalize_func = Code("""
|
|
function(key, value) {
|
|
return value.t / value.c;
|
|
}
|
|
""")
|
|
|
|
for result in self.map_reduce(map_func, reduce_func,
|
|
finalize_f=finalize_func, output='inline'):
|
|
return result.value
|
|
else:
|
|
return 0
|
|
|
|
def item_frequencies(self, field, normalize=False, map_reduce=True):
|
|
"""Returns a dictionary of all items present in a field across
|
|
the whole queried set of documents, and their corresponding frequency.
|
|
This is useful for generating tag clouds, or searching documents.
|
|
|
|
.. note::
|
|
|
|
Can only do direct simple mappings and cannot map across
|
|
:class:`~mongoengine.fields.ReferenceField` or
|
|
:class:`~mongoengine.fields.GenericReferenceField` for more complex
|
|
counting a manual map reduce call would is required.
|
|
|
|
If the field is a :class:`~mongoengine.fields.ListField`, the items within
|
|
each list will be counted individually.
|
|
|
|
:param field: the field to use
|
|
:param normalize: normalize the results so they add to 1.0
|
|
:param map_reduce: Use map_reduce over exec_js
|
|
|
|
.. versionchanged:: 0.5 defaults to map_reduce and can handle embedded
|
|
document lookups
|
|
"""
|
|
if map_reduce:
|
|
return self._item_frequencies_map_reduce(field,
|
|
normalize=normalize)
|
|
return self._item_frequencies_exec_js(field, normalize=normalize)
|
|
|
|
# Iterator helpers
|
|
|
|
def next(self):
|
|
"""Wrap the result in a :class:`~mongoengine.Document` object.
|
|
"""
|
|
if self._limit == 0 or self._none:
|
|
raise StopIteration
|
|
|
|
raw_doc = self._cursor.next()
|
|
if self._as_pymongo:
|
|
return self._get_as_pymongo(raw_doc)
|
|
doc = self._document._from_son(raw_doc,
|
|
_auto_dereference=self._auto_dereference, only_fields=self.only_fields)
|
|
if self._scalar:
|
|
return self._get_scalar(doc)
|
|
|
|
return doc
|
|
|
|
def rewind(self):
|
|
"""Rewind the cursor to its unevaluated state.
|
|
|
|
.. versionadded:: 0.3
|
|
"""
|
|
self._iter = False
|
|
self._cursor.rewind()
|
|
|
|
# Properties
|
|
|
|
@property
|
|
def _collection(self):
|
|
"""Property that returns the collection object. This allows us to
|
|
perform operations only if the collection is accessed.
|
|
"""
|
|
return self._collection_obj
|
|
|
|
@property
|
|
def _cursor_args(self):
|
|
cursor_args = {
|
|
'snapshot': self._snapshot,
|
|
'timeout': self._timeout
|
|
}
|
|
if self._read_preference is not None:
|
|
cursor_args['read_preference'] = self._read_preference
|
|
else:
|
|
cursor_args['slave_okay'] = self._slave_okay
|
|
if self._loaded_fields:
|
|
cursor_args['fields'] = self._loaded_fields.as_dict()
|
|
|
|
if self._include_text_scores:
|
|
if 'fields' not in cursor_args:
|
|
cursor_args['fields'] = {}
|
|
|
|
cursor_args['fields']['text_score'] = {'$meta': "textScore"}
|
|
|
|
return cursor_args
|
|
|
|
@property
|
|
def _cursor(self):
|
|
if self._cursor_obj is None:
|
|
|
|
self._cursor_obj = self._collection.find(self._query,
|
|
**self._cursor_args)
|
|
# Apply where clauses to cursor
|
|
if self._where_clause:
|
|
where_clause = self._sub_js_fields(self._where_clause)
|
|
self._cursor_obj.where(where_clause)
|
|
|
|
if self._ordering:
|
|
# Apply query ordering
|
|
self._cursor_obj.sort(self._ordering)
|
|
elif self._ordering is None and self._document._meta['ordering']:
|
|
# Otherwise, apply the ordering from the document model, unless
|
|
# it's been explicitly cleared via order_by with no arguments
|
|
order = self._get_order_by(self._document._meta['ordering'])
|
|
self._cursor_obj.sort(order)
|
|
|
|
if self._limit is not None:
|
|
self._cursor_obj.limit(self._limit)
|
|
|
|
if self._skip is not None:
|
|
self._cursor_obj.skip(self._skip)
|
|
|
|
if self._hint != -1:
|
|
self._cursor_obj.hint(self._hint)
|
|
|
|
return self._cursor_obj
|
|
|
|
def __deepcopy__(self, memo):
|
|
"""Essential for chained queries with ReferenceFields involved"""
|
|
return self.clone()
|
|
|
|
@property
|
|
def _query(self):
|
|
if self._mongo_query is None:
|
|
self._mongo_query = self._query_obj.to_query(self._document)
|
|
if self._class_check and self._initial_query:
|
|
if "_cls" in self._mongo_query:
|
|
self._mongo_query = {"$and": [self._initial_query, self._mongo_query]}
|
|
else:
|
|
self._mongo_query.update(self._initial_query)
|
|
return self._mongo_query
|
|
|
|
@property
|
|
def _dereference(self):
|
|
if not self.__dereference:
|
|
self.__dereference = _import_class('DeReference')()
|
|
return self.__dereference
|
|
|
|
def no_dereference(self):
|
|
"""Turn off any dereferencing for the results of this queryset.
|
|
"""
|
|
queryset = self.clone()
|
|
queryset._auto_dereference = False
|
|
return queryset
|
|
|
|
# Helper Functions
|
|
|
|
def _item_frequencies_map_reduce(self, field, normalize=False):
|
|
map_func = """
|
|
function() {
|
|
var path = '{{~%(field)s}}'.split('.');
|
|
var field = this;
|
|
|
|
for (p in path) {
|
|
if (typeof field != 'undefined')
|
|
field = field[path[p]];
|
|
else
|
|
break;
|
|
}
|
|
if (field && field.constructor == Array) {
|
|
field.forEach(function(item) {
|
|
emit(item, 1);
|
|
});
|
|
} else if (typeof field != 'undefined') {
|
|
emit(field, 1);
|
|
} else {
|
|
emit(null, 1);
|
|
}
|
|
}
|
|
""" % dict(field=field)
|
|
reduce_func = """
|
|
function(key, values) {
|
|
var total = 0;
|
|
var valuesSize = values.length;
|
|
for (var i=0; i < valuesSize; i++) {
|
|
total += parseInt(values[i], 10);
|
|
}
|
|
return total;
|
|
}
|
|
"""
|
|
values = self.map_reduce(map_func, reduce_func, 'inline')
|
|
frequencies = {}
|
|
for f in values:
|
|
key = f.key
|
|
if isinstance(key, float):
|
|
if int(key) == key:
|
|
key = int(key)
|
|
frequencies[key] = int(f.value)
|
|
|
|
if normalize:
|
|
count = sum(frequencies.values())
|
|
frequencies = dict([(k, float(v) / count)
|
|
for k, v in frequencies.items()])
|
|
|
|
return frequencies
|
|
|
|
def _item_frequencies_exec_js(self, field, normalize=False):
|
|
"""Uses exec_js to execute"""
|
|
freq_func = """
|
|
function(path) {
|
|
var path = path.split('.');
|
|
|
|
var total = 0.0;
|
|
db[collection].find(query).forEach(function(doc) {
|
|
var field = doc;
|
|
for (p in path) {
|
|
if (field)
|
|
field = field[path[p]];
|
|
else
|
|
break;
|
|
}
|
|
if (field && field.constructor == Array) {
|
|
total += field.length;
|
|
} else {
|
|
total++;
|
|
}
|
|
});
|
|
|
|
var frequencies = {};
|
|
var types = {};
|
|
var inc = 1.0;
|
|
|
|
db[collection].find(query).forEach(function(doc) {
|
|
field = doc;
|
|
for (p in path) {
|
|
if (field)
|
|
field = field[path[p]];
|
|
else
|
|
break;
|
|
}
|
|
if (field && field.constructor == Array) {
|
|
field.forEach(function(item) {
|
|
frequencies[item] = inc + (isNaN(frequencies[item]) ? 0: frequencies[item]);
|
|
});
|
|
} else {
|
|
var item = field;
|
|
types[item] = item;
|
|
frequencies[item] = inc + (isNaN(frequencies[item]) ? 0: frequencies[item]);
|
|
}
|
|
});
|
|
return [total, frequencies, types];
|
|
}
|
|
"""
|
|
total, data, types = self.exec_js(freq_func, field)
|
|
values = dict([(types.get(k), int(v)) for k, v in data.iteritems()])
|
|
|
|
if normalize:
|
|
values = dict([(k, float(v) / total) for k, v in values.items()])
|
|
|
|
frequencies = {}
|
|
for k, v in values.iteritems():
|
|
if isinstance(k, float):
|
|
if int(k) == k:
|
|
k = int(k)
|
|
|
|
frequencies[k] = v
|
|
|
|
return frequencies
|
|
|
|
def _fields_to_dbfields(self, fields, subdoc=False):
|
|
"""Translate fields paths to its db equivalents"""
|
|
ret = []
|
|
subclasses = []
|
|
document = self._document
|
|
if document._meta['allow_inheritance']:
|
|
subclasses = [get_document(x)
|
|
for x in document._subclasses][1:]
|
|
for field in fields:
|
|
try:
|
|
field = ".".join(f.db_field for f in
|
|
document._lookup_field(field.split('.')))
|
|
ret.append(field)
|
|
except LookUpError, err:
|
|
found = False
|
|
for subdoc in subclasses:
|
|
try:
|
|
subfield = ".".join(f.db_field for f in
|
|
subdoc._lookup_field(field.split('.')))
|
|
ret.append(subfield)
|
|
found = True
|
|
break
|
|
except LookUpError, e:
|
|
pass
|
|
|
|
if not found:
|
|
raise err
|
|
return ret
|
|
|
|
def _get_order_by(self, keys):
|
|
"""Creates a list of order by fields
|
|
"""
|
|
key_list = []
|
|
for key in keys:
|
|
if not key:
|
|
continue
|
|
|
|
if key == '$text_score':
|
|
# automatically set to include text scores
|
|
self._include_text_scores = True
|
|
key_list.append(('text_score', {'$meta': "textScore"}))
|
|
continue
|
|
|
|
direction = pymongo.ASCENDING
|
|
if key[0] == '-':
|
|
direction = pymongo.DESCENDING
|
|
if key[0] in ('-', '+'):
|
|
key = key[1:]
|
|
key = key.replace('__', '.')
|
|
try:
|
|
key = self._document._translate_field_name(key)
|
|
except:
|
|
pass
|
|
key_list.append((key, direction))
|
|
|
|
if self._cursor_obj and key_list:
|
|
self._cursor_obj.sort(key_list)
|
|
return key_list
|
|
|
|
def _get_scalar(self, doc):
|
|
|
|
def lookup(obj, name):
|
|
chunks = name.split('__')
|
|
for chunk in chunks:
|
|
obj = getattr(obj, chunk)
|
|
return obj
|
|
|
|
data = [lookup(doc, n) for n in self._scalar]
|
|
if len(data) == 1:
|
|
return data[0]
|
|
|
|
return tuple(data)
|
|
|
|
def _get_as_pymongo(self, row):
|
|
# Extract which fields paths we should follow if .fields(...) was
|
|
# used. If not, handle all fields.
|
|
if not getattr(self, '__as_pymongo_fields', None):
|
|
self.__as_pymongo_fields = []
|
|
|
|
for field in self._loaded_fields.fields - set(['_cls']):
|
|
self.__as_pymongo_fields.append(field)
|
|
while '.' in field:
|
|
field, _ = field.rsplit('.', 1)
|
|
self.__as_pymongo_fields.append(field)
|
|
|
|
all_fields = not self.__as_pymongo_fields
|
|
|
|
def clean(data, path=None):
|
|
path = path or ''
|
|
|
|
if isinstance(data, dict):
|
|
new_data = {}
|
|
for key, value in data.iteritems():
|
|
new_path = '%s.%s' % (path, key) if path else key
|
|
|
|
if all_fields:
|
|
include_field = True
|
|
elif self._loaded_fields.value == QueryFieldList.ONLY:
|
|
include_field = new_path in self.__as_pymongo_fields
|
|
else:
|
|
include_field = new_path not in self.__as_pymongo_fields
|
|
|
|
if include_field:
|
|
new_data[key] = clean(value, path=new_path)
|
|
data = new_data
|
|
elif isinstance(data, list):
|
|
data = [clean(d, path=path) for d in data]
|
|
else:
|
|
if self._as_pymongo_coerce:
|
|
# If we need to coerce types, we need to determine the
|
|
# type of this field and use the corresponding
|
|
# .to_python(...)
|
|
from mongoengine.fields import EmbeddedDocumentField
|
|
|
|
obj = self._document
|
|
for chunk in path.split('.'):
|
|
obj = getattr(obj, chunk, None)
|
|
if obj is None:
|
|
break
|
|
elif isinstance(obj, EmbeddedDocumentField):
|
|
obj = obj.document_type
|
|
if obj and data is not None:
|
|
data = obj.to_python(data)
|
|
return data
|
|
|
|
return clean(row)
|
|
|
|
def _sub_js_fields(self, code):
|
|
"""When fields are specified with [~fieldname] syntax, where
|
|
*fieldname* is the Python name of a field, *fieldname* will be
|
|
substituted for the MongoDB name of the field (specified using the
|
|
:attr:`name` keyword argument in a field's constructor).
|
|
"""
|
|
|
|
def field_sub(match):
|
|
# Extract just the field name, and look up the field objects
|
|
field_name = match.group(1).split('.')
|
|
fields = self._document._lookup_field(field_name)
|
|
# Substitute the correct name for the field into the javascript
|
|
return u'["%s"]' % fields[-1].db_field
|
|
|
|
def field_path_sub(match):
|
|
# Extract just the field name, and look up the field objects
|
|
field_name = match.group(1).split('.')
|
|
fields = self._document._lookup_field(field_name)
|
|
# Substitute the correct name for the field into the javascript
|
|
return ".".join([f.db_field for f in fields])
|
|
|
|
code = re.sub(u'\[\s*~([A-z_][A-z_0-9.]+?)\s*\]', field_sub, code)
|
|
code = re.sub(u'\{\{\s*~([A-z_][A-z_0-9.]+?)\s*\}\}', field_path_sub,
|
|
code)
|
|
return code
|
|
|
|
def _chainable_method(self, method_name, val):
|
|
queryset = self.clone()
|
|
method = getattr(queryset._cursor, method_name)
|
|
method(val)
|
|
setattr(queryset, "_" + method_name, val)
|
|
return queryset
|
|
|
|
# Deprecated
|
|
def ensure_index(self, **kwargs):
|
|
"""Deprecated use :func:`Document.ensure_index`"""
|
|
msg = ("Doc.objects()._ensure_index() is deprecated. "
|
|
"Use Doc.ensure_index() instead.")
|
|
warnings.warn(msg, DeprecationWarning)
|
|
self._document.__class__.ensure_index(**kwargs)
|
|
return self
|
|
|
|
def _ensure_indexes(self):
|
|
"""Deprecated use :func:`~Document.ensure_indexes`"""
|
|
msg = ("Doc.objects()._ensure_indexes() is deprecated. "
|
|
"Use Doc.ensure_indexes() instead.")
|
|
warnings.warn(msg, DeprecationWarning)
|
|
self._document.__class__.ensure_indexes()
|