def __init__(self, document, collection):
self._document = document
self._collection_obj = collection
self._accessed_collection = False
self._query = {}
self._where_clause = None
self._loaded_fields = []
self._ordering = []
self.transform = TransformDjango()
# If inheritance is allowed, only return instances and instances of
# subclasses of the class being used
#if document._meta.get('allow_inheritance'):
#self._query = {'_types': self._document._class_name}
self._cursor_obj = None
self._limit = None
self._skip = None
class QuerySet(object):
"""A set of results returned from a query. Wraps a MongoDB cursor,
providing :class:`~mongoengine.Document` objects as the results.
"""
def __init__(self, document, collection):
self._document = document
self._collection_obj = collection
self._accessed_collection = False
self._query = {}
self._where_clause = None
self._loaded_fields = []
self._ordering = []
self.transform = TransformDjango()
# If inheritance is allowed, only return instances and instances of
# subclasses of the class being used
#if document._meta.get('allow_inheritance'):
#self._query = {'_types': self._document._class_name}
self._cursor_obj = None
self._limit = None
self._skip = None
#required for compatibility with django
#self.model = InternalModel(document)
def __call__(self, q_obj=None, **query):
"""Filter the selected documents by calling the
:class:`~mongoengine.queryset.QuerySet` with a query.
:param q_obj: a :class:`~mongoengine.queryset.Q` object to be used in
the query; the :class:`~mongoengine.queryset.QuerySet` is filtered
multiple times with different :class:`~mongoengine.queryset.Q`
objects, only the last one will be used
:param query: Django-style query keyword arguments
"""
if q_obj:
self._where_clause = q_obj.as_js(self._document)
query = QuerySet._transform_query(_doc_cls=self._document, **query)
self._query.update(query)
return self
def filter(self, *q_objs, **query):
"""An alias of :meth:`~mongoengine.queryset.QuerySet.__call__`
"""
return self.__call__(*q_objs, **query)
def find(self, query):
self._query.update(self.transform.transform_incoming(query, self._collection))
return self
def exclude(self, *q_objs, **query):
"""An alias of :meth:`~mongoengine.queryset.QuerySet.__call__`
"""
query["not"] = True
return self.__call__(*q_objs, **query)
def all(self):
"""An alias of :meth:`~mongoengine.queryset.QuerySet.__call__`
"""
return self.__call__()
def distinct(self, *args, **kwargs):
"""
Distinct method
"""
return self._cursor.distinct(*args, **kwargs)
@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
def values(self, *args):
return (args and [dict(zip(args,[getattr(doc, key) for key in args])) for doc in self]) or [obj for obj in self._cursor.clone()]
def values_list(self, *args, **kwargs):
flat = kwargs.pop("flat", False)
if flat and len(args) != 1:
raise Exception("args len must be 1 when flat=True")
return (flat and self.distinct(args[0] if not args[0] in ["id", "pk"] else "_id")) or zip(*[self.distinct(field if not field in ["id", "pk"] else "_id") for field in args])
#
# if self._document._meta['geo_indexes'] and \
# pymongo.version >= "1.5.1":
# from pymongo import GEO2D
# for index in self._document._meta['geo_indexes']:
# self._collection.ensure_index([(index, GEO2D)])
#
# # Ensure all needed field indexes are created
# for field_name, field_instance in self._document._fields.iteritems():
# if field_instance.__class__.__name__ == 'GeoLocationField':
# self._collection.ensure_index([(field_name, pymongo.GEO2D),])
# return self._collection_obj
@property
def _cursor(self):
if self._cursor_obj is None:
cursor_args = {}
if self._loaded_fields:
cursor_args = {'fields': self._loaded_fields}
self._cursor_obj = self._collection.find(self._query,
**cursor_args)
# Apply where clauses to cursor
if self._where_clause:
self._cursor_obj.where(self._where_clause)
# apply default ordering
# if self._document._meta['ordering']:
# self.order_by(*self._document._meta['ordering'])
return self._cursor_obj.clone()
@classmethod
def _lookup_field(cls, document, fields):
"""
Looks for "field" in "document"
"""
if isinstance(fields, (tuple, list)):
return [document._meta.get_field_by_name((field == "pk" and "id") or field)[0] for field in fields]
return document._meta.get_field_by_name((fields == "pk" and "id") or fields)[0]
@classmethod
def _translate_field_name(cls, doc_cls, field, sep='.'):
"""Translate a field attribute name to a database field name.
"""
parts = field.split(sep)
parts = [f.attname for f in QuerySet._lookup_field(doc_cls, parts)]
return '.'.join(parts)
@classmethod
def _transform_query(self, _doc_cls=None, **parameters):
"""
Converts parameters to mongodb queries.
"""
spec = {}
operators = ['ne', 'gt', 'gte', 'lt', 'lte', 'in', 'nin', 'mod', 'all', 'size', 'exists']
match_operators = ['contains', 'icontains', 'startswith', 'istartswith', 'endswith', 'iendswith', 'exact', 'iexact']
exclude = parameters.pop("not", False)
for key, value in parameters.items():
parts = key.split("__")
lookup_type = (len(parts)>=2) and ( parts[-1] in operators + match_operators and parts.pop()) or ""
# Let's get the right field and be sure that it exists
parts[0] = QuerySet._lookup_field(_doc_cls, parts[0]).attname
if not lookup_type and len(parts)==1:
if exclude:
value = {"$ne" : value}
spec.update({parts[0] : value})
continue
if parts[0] == "id":
parts[0] = "_id"
value = [isinstance(par, basestring) and ObjectId(par) or par for par in value]
if lookup_type in ['contains', 'icontains',
'startswith', 'istartswith',
'endswith', 'iendswith',
'exact', 'iexact']:
flags = 0
if lookup_type.startswith('i'):
flags = re.IGNORECASE
lookup_type = lookup_type.lstrip('i')
regex = r'%s'
if lookup_type == 'startswith':
regex = r'^%s'
elif lookup_type == 'endswith':
regex = r'%s$'
elif lookup_type == 'exact':
regex = r'^%s$'
value = re.compile(regex % value, flags)
elif lookup_type in operators:
value = { "$" + lookup_type : value}
elif lookup_type and len(parts)==1:
raise DatabaseError("Unsupported lookup type: %r" % lookup_type)
key = '.'.join(parts)
if exclude:
value = {"$ne" : value}
spec.update({key : value})
return spec
def get(self, *q_objs, **query):
"""Retrieve the the matching object raising id django is available
:class:`~django.core.exceptions.MultipleObjectsReturned` or
:class:`~django.core.exceptions.ObjectDoesNotExist` exceptions if multiple or
no results are found.
If django is not available:
:class:`~mongoengine.queryset.MultipleObjectsReturned` or
`DocumentName.MultipleObjectsReturned` exception if multiple results and
:class:`~mongoengine.queryset.DoesNotExist` or `DocumentName.DoesNotExist`
if no results are found.
.. versionadded:: 0.3
"""
self.__call__(*q_objs, **query)
count = self.count()
if count == 1:
return self[0]
elif count > 1:
message = u'%d items returned, instead of 1' % count
raise self._document.MultipleObjectsReturned(message)
else:
raise self._document.DoesNotExist("%s matching query does not exist."
% self._document._meta.object_name)
def get_or_create(self, *q_objs, **query):
"""Retrieve unique object or create, if it doesn't exist. Returns a tuple of
``(object, created)``, where ``object`` is the retrieved or created object
and ``created`` is a boolean specifying whether a new object was created. Raises
:class:`~mongoengine.queryset.MultipleObjectsReturned` or
`DocumentName.MultipleObjectsReturned` if multiple results are found.
A new document will be created if the document doesn't exists; a
dictionary of default values for the new document may be provided as a
keyword argument called :attr:`defaults`.
.. versionadded:: 0.3
"""
defaults = query.get('defaults', {})
if 'defaults' in query:
del query['defaults']
self.__call__(*q_objs, **query)
count = self.count()
if count == 0:
query.update(defaults)
doc = self._document(**query)
doc.save()
return doc, True
elif count == 1:
return self.first(), False
else:
message = u'%d items returned, instead of 1' % count
raise self._document.MultipleObjectsReturned(message)
def first(self):
"""Retrieve the first object matching the query.
"""
try:
result = self[0]
except IndexError:
result = None
return result
def with_id(self, object_id):
"""Retrieve the object matching the id provided.
:param object_id: the value for the id of the document to look up
"""
id_field = self._document._meta['id_field']
object_id = self._document._fields[id_field].to_mongo(object_id)
result = self._collection.find_one({'_id': (not isinstance(object_id, ObjectId) and ObjectId(object_id)) or object_id})
if result is not None:
result = self._document(**dict_keys_to_str(result))
return result
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': [ (not isinstance(id, ObjectId) and ObjectId(id)) or id for id in object_ids]}})
for doc in docs:
doc_map[str(doc['id'])] = self._document(**dict_keys_to_str(doc))
return doc_map
def count(self):
"""Count the selected elements in the query.
"""
if self._limit == 0:
return 0
return self._cursor.count(with_limit_and_skip=False)
def __len__(self):
return self.count()
def map_reduce(self, map_f, reduce_f, finalize_f=None, limit=None,
scope=None, keep_temp=False):
"""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:`~pymongo.code.Code` or string
:param reduce_f: reduce function, as
:class:`~pymongo.code.Code` or string
: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
:param keep_temp: keep temporary table (boolean, default ``True``)
Returns an iterator yielding
:class:`~mongoengine.document.MapReduceDocument`.
.. note:: Map/Reduce requires server version **>= 1.1.1**. The PyMongo
:meth:`~pymongo.collection.Collection.map_reduce` helper requires
PyMongo version **>= 1.2**.
.. versionadded:: 0.3
"""
#from document import MapReduceDocument
if not hasattr(self._collection, "map_reduce"):
raise NotImplementedError("Requires MongoDB >= 1.1.1")
map_f_scope = {}
if isinstance(map_f, pymongo.code.Code):
map_f_scope = map_f.scope
map_f = unicode(map_f)
# map_f = pymongo.code.Code(self._sub_js_fields(map_f), map_f_scope)
map_f = pymongo.code.Code(map_f, map_f_scope)
reduce_f_scope = {}
if isinstance(reduce_f, pymongo.code.Code):
reduce_f_scope = reduce_f.scope
reduce_f = unicode(reduce_f)
# reduce_f_code = self._sub_js_fields(reduce_f)
reduce_f_code = reduce_f
reduce_f = pymongo.code.Code(reduce_f_code, reduce_f_scope)
mr_args = {'query': self._query, 'keeptemp': keep_temp}
if finalize_f:
finalize_f_scope = {}
if isinstance(finalize_f, pymongo.code.Code):
finalize_f_scope = finalize_f.scope
finalize_f = unicode(finalize_f)
# finalize_f_code = self._sub_js_fields(finalize_f)
finalize_f_code = finalize_f
finalize_f = pymongo.code.Code(finalize_f_code, finalize_f_scope)
mr_args['finalize'] = finalize_f
if scope:
mr_args['scope'] = scope
if limit:
mr_args['limit'] = limit
results = self._collection.map_reduce(map_f, reduce_f, **mr_args)
results = results.find()
if self._ordering:
results = results.sort(self._ordering)
for doc in results:
yield self._document.objects.with_id(doc['value'])
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
"""
if n == 0:
self._cursor.limit(1)
else:
self._cursor.limit(n)
self._limit = n
# Return self to allow chaining
return self
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
"""
self._cursor.skip(n)
self._skip = n
return self
def __getitem__(self, key):
"""Support skip and limit using getitem and slicing syntax.
"""
# Slice provided
if isinstance(key, slice):
try:
self._cursor_obj = self._cursor[key]
self._skip, self._limit = key.start, key.stop
except IndexError, err:
# PyMongo raises an error if key.start == key.stop, catch it,
# bin it, kill it.
start = key.start or 0
if start >= 0 and key.stop >= 0 and key.step is None:
if start == key.stop:
self.limit(0)
self._skip, self._limit = key.start, key.stop - start
return self
raise err
# Allow further QuerySet modifications to be performed
return self
# Integer index provided
elif isinstance(key, int):
return self._document(**dict_keys_to_str(self._cursor[key]))