/
document.py
955 lines (795 loc) · 38.6 KB
/
document.py
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import warnings
import pymongo
import re
from pymongo.read_preferences import ReadPreference
from bson.dbref import DBRef
from mongoengine import signals
from mongoengine.common import _import_class
from mongoengine.base import (
DocumentMetaclass,
TopLevelDocumentMetaclass,
BaseDocument,
BaseDict,
BaseList,
EmbeddedDocumentList,
ALLOW_INHERITANCE,
get_document
)
from mongoengine.errors import InvalidQueryError, InvalidDocumentError
from mongoengine.python_support import IS_PYMONGO_3
from mongoengine.queryset import (OperationError, NotUniqueError,
QuerySet, transform)
from mongoengine.connection import get_db, DEFAULT_CONNECTION_NAME
from mongoengine.context_managers import switch_db, switch_collection
__all__ = ('Document', 'EmbeddedDocument', 'DynamicDocument',
'DynamicEmbeddedDocument', 'OperationError',
'InvalidCollectionError', 'NotUniqueError', 'MapReduceDocument')
def includes_cls(fields):
""" Helper function used for ensuring and comparing indexes
"""
first_field = None
if len(fields):
if isinstance(fields[0], basestring):
first_field = fields[0]
elif isinstance(fields[0], (list, tuple)) and len(fields[0]):
first_field = fields[0][0]
return first_field == '_cls'
class InvalidCollectionError(Exception):
pass
class EmbeddedDocument(BaseDocument):
"""A :class:`~mongoengine.Document` that isn't stored in its own
collection. :class:`~mongoengine.EmbeddedDocument`\ s should be used as
fields on :class:`~mongoengine.Document`\ s through the
:class:`~mongoengine.EmbeddedDocumentField` field type.
A :class:`~mongoengine.EmbeddedDocument` subclass may be itself subclassed,
to create a specialised version of the embedded document that will be
stored in the same collection. To facilitate this behaviour a `_cls`
field is added to documents (hidden though the MongoEngine interface).
To disable this behaviour and remove the dependence on the presence of
`_cls` set :attr:`allow_inheritance` to ``False`` in the :attr:`meta`
dictionary.
"""
__slots__ = ('_instance')
# The __metaclass__ attribute is removed by 2to3 when running with Python3
# my_metaclass is defined so that metaclass can be queried in Python 2 & 3
my_metaclass = DocumentMetaclass
__metaclass__ = DocumentMetaclass
def __init__(self, *args, **kwargs):
super(EmbeddedDocument, self).__init__(*args, **kwargs)
self._instance = None
self._changed_fields = []
def __eq__(self, other):
if isinstance(other, self.__class__):
return self._data == other._data
return False
def __ne__(self, other):
return not self.__eq__(other)
def save(self, *args, **kwargs):
self._instance.save(*args, **kwargs)
def reload(self, *args, **kwargs):
self._instance.reload(*args, **kwargs)
class Document(BaseDocument):
"""The base class used for defining the structure and properties of
collections of documents stored in MongoDB. Inherit from this class, and
add fields as class attributes to define a document's structure.
Individual documents may then be created by making instances of the
:class:`~mongoengine.Document` subclass.
By default, the MongoDB collection used to store documents created using a
:class:`~mongoengine.Document` subclass will be the name of the subclass
converted to lowercase. A different collection may be specified by
providing :attr:`collection` to the :attr:`meta` dictionary in the class
definition.
A :class:`~mongoengine.Document` subclass may be itself subclassed, to
create a specialised version of the document that will be stored in the
same collection. To facilitate this behaviour a `_cls`
field is added to documents (hidden though the MongoEngine interface).
To disable this behaviour and remove the dependence on the presence of
`_cls` set :attr:`allow_inheritance` to ``False`` in the :attr:`meta`
dictionary.
A :class:`~mongoengine.Document` may use a **Capped Collection** by
specifying :attr:`max_documents` and :attr:`max_size` in the :attr:`meta`
dictionary. :attr:`max_documents` is the maximum number of documents that
is allowed to be stored in the collection, and :attr:`max_size` is the
maximum size of the collection in bytes. :attr:`max_size` is rounded up
to the next multiple of 256 by MongoDB internally and mongoengine before.
Use also a multiple of 256 to avoid confusions. If :attr:`max_size` is not
specified and :attr:`max_documents` is, :attr:`max_size` defaults to
10485760 bytes (10MB).
Indexes may be created by specifying :attr:`indexes` in the :attr:`meta`
dictionary. The value should be a list of field names or tuples of field
names. Index direction may be specified by prefixing the field names with
a **+** or **-** sign.
Automatic index creation can be disabled by specifying
:attr:`auto_create_index` in the :attr:`meta` dictionary. If this is set to
False then indexes will not be created by MongoEngine. This is useful in
production systems where index creation is performed as part of a
deployment system.
By default, _cls will be added to the start of every index (that
doesn't contain a list) if allow_inheritance is True. This can be
disabled by either setting cls to False on the specific index or
by setting index_cls to False on the meta dictionary for the document.
By default, any extra attribute existing in stored data but not declared
in your model will raise a :class:`~mongoengine.FieldDoesNotExist` error.
This can be disabled by setting :attr:`strict` to ``False``
in the :attr:`meta` dictionary.
"""
# The __metaclass__ attribute is removed by 2to3 when running with Python3
# my_metaclass is defined so that metaclass can be queried in Python 2 & 3
my_metaclass = TopLevelDocumentMetaclass
__metaclass__ = TopLevelDocumentMetaclass
__slots__ = ('__objects',)
def pk():
"""Primary key alias
"""
def fget(self):
if 'id_field' not in self._meta:
return None
return getattr(self, self._meta['id_field'])
def fset(self, value):
return setattr(self, self._meta['id_field'], value)
return property(fget, fset)
pk = pk()
@classmethod
def _get_db(cls):
"""Some Model using other db_alias"""
return get_db(cls._meta.get("db_alias", DEFAULT_CONNECTION_NAME))
@classmethod
def _get_collection(cls):
"""Returns the collection for the document."""
# TODO: use new get_collection() with PyMongo3 ?
if not hasattr(cls, '_collection') or cls._collection is None:
db = cls._get_db()
collection_name = cls._get_collection_name()
# Create collection as a capped collection if specified
if cls._meta.get('max_size') or cls._meta.get('max_documents'):
# Get max document limit and max byte size from meta
max_size = cls._meta.get('max_size') or 10 * 2 ** 20 # 10MB default
max_documents = cls._meta.get('max_documents')
# Round up to next 256 bytes as MongoDB would do it to avoid exception
if max_size % 256:
max_size = (max_size // 256 + 1) * 256
if collection_name in db.collection_names():
cls._collection = db[collection_name]
# The collection already exists, check if its capped
# options match the specified capped options
options = cls._collection.options()
if options.get('max') != max_documents or \
options.get('size') != max_size:
msg = (('Cannot create collection "%s" as a capped '
'collection as it already exists')
% cls._collection)
raise InvalidCollectionError(msg)
else:
# Create the collection as a capped collection
opts = {'capped': True, 'size': max_size}
if max_documents:
opts['max'] = max_documents
cls._collection = db.create_collection(
collection_name, **opts
)
else:
cls._collection = db[collection_name]
if cls._meta.get('auto_create_index', True):
cls.ensure_indexes()
return cls._collection
def modify(self, query={}, **update):
"""Perform an atomic update of the document in the database and reload
the document object using updated version.
Returns True if the document has been updated or False if the document
in the database doesn't match the query.
.. note:: All unsaved changes that has been made to the document are
rejected if the method returns True.
:param query: the update will be performed only if the document in the
database matches the query
:param update: Django-style update keyword arguments
"""
if self.pk is None:
raise InvalidDocumentError("The document does not have a primary key.")
id_field = self._meta["id_field"]
query = query.copy() if isinstance(query, dict) else query.to_query(self)
if id_field not in query:
query[id_field] = self.pk
elif query[id_field] != self.pk:
raise InvalidQueryError("Invalid document modify query: it must modify only this document.")
updated = self._qs(**query).modify(new=True, **update)
if updated is None:
return False
for field in self._fields_ordered:
setattr(self, field, self._reload(field, updated[field]))
self._changed_fields = updated._changed_fields
self._created = False
return True
def save(self, force_insert=False, validate=True, clean=True,
write_concern=None, cascade=None, cascade_kwargs=None,
_refs=None, save_condition=None, **kwargs):
"""Save the :class:`~mongoengine.Document` to the database. If the
document already exists, it will be updated, otherwise it will be
created.
:param force_insert: only try to create a new document, don't allow
updates of existing documents
:param validate: validates the document; set to ``False`` to skip.
:param clean: call the document clean method, requires `validate` to be
True.
:param write_concern: Extra keyword arguments are passed down to
:meth:`~pymongo.collection.Collection.save` OR
:meth:`~pymongo.collection.Collection.insert`
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 cascade: Sets the flag for cascading saves. You can set a
default by setting "cascade" in the document __meta__
:param cascade_kwargs: (optional) kwargs dictionary to be passed throw
to cascading saves. Implies ``cascade=True``.
:param _refs: A list of processed references used in cascading saves
:param save_condition: only perform save if matching record in db
satisfies condition(s) (e.g. version number).
Raises :class:`OperationError` if the conditions are not satisfied
.. versionchanged:: 0.5
In existing documents it only saves changed fields using
set / unset. Saves are cascaded and any
:class:`~bson.dbref.DBRef` objects that have changes are
saved as well.
.. versionchanged:: 0.6
Added cascading saves
.. versionchanged:: 0.8
Cascade saves are optional and default to False. If you want
fine grain control then you can turn off using document
meta['cascade'] = True. Also you can pass different kwargs to
the cascade save using cascade_kwargs which overwrites the
existing kwargs with custom values.
.. versionchanged:: 0.8.5
Optional save_condition that only overwrites existing documents
if the condition is satisfied in the current db record.
.. versionchanged:: 0.10
:class:`OperationError` exception raised if save_condition fails.
"""
signals.pre_save.send(self.__class__, document=self)
if validate:
self.validate(clean=clean)
if write_concern is None:
write_concern = {"w": 1}
doc = self.to_mongo()
created = ('_id' not in doc or self._created or force_insert)
signals.pre_save_post_validation.send(self.__class__, document=self,
created=created)
try:
collection = self._get_collection()
if self._meta.get('auto_create_index', True):
self.ensure_indexes()
if created:
if force_insert:
object_id = collection.insert(doc, **write_concern)
else:
object_id = collection.save(doc, **write_concern)
# In PyMongo 3.0, the save() call calls internally the _update() call
# but they forget to return the _id value passed back, therefore getting it back here
# Correct behaviour in 2.X and in 3.0.1+ versions
if not object_id and pymongo.version_tuple == (3, 0):
pk_as_mongo_obj = self._fields.get(self._meta['id_field']).to_mongo(self.pk)
object_id = self._qs.filter(pk=pk_as_mongo_obj).first() and \
self._qs.filter(pk=pk_as_mongo_obj).first().pk
else:
object_id = doc['_id']
updates, removals = self._delta()
# Need to add shard key to query, or you get an error
if save_condition is not None:
select_dict = transform.query(self.__class__,
**save_condition)
else:
select_dict = {}
select_dict['_id'] = object_id
shard_key = self.__class__._meta.get('shard_key', tuple())
for k in shard_key:
actual_key = self._db_field_map.get(k, k)
select_dict[actual_key] = doc[actual_key]
def is_new_object(last_error):
if last_error is not None:
updated = last_error.get("updatedExisting")
if updated is not None:
return not updated
return created
update_query = {}
if updates:
update_query["$set"] = updates
if removals:
update_query["$unset"] = removals
if updates or removals:
upsert = save_condition is None
last_error = collection.update(select_dict, update_query,
upsert=upsert, **write_concern)
if not upsert and last_error['nModified'] == 0:
raise OperationError('Race condition preventing'
' document update detected')
created = is_new_object(last_error)
if cascade is None:
cascade = self._meta.get(
'cascade', False) or cascade_kwargs is not None
if cascade:
kwargs = {
"force_insert": force_insert,
"validate": validate,
"write_concern": write_concern,
"cascade": cascade
}
if cascade_kwargs: # Allow granular control over cascades
kwargs.update(cascade_kwargs)
kwargs['_refs'] = _refs
self.cascade_save(**kwargs)
except pymongo.errors.DuplicateKeyError, err:
message = u'Tried to save duplicate unique keys (%s)'
raise NotUniqueError(message % unicode(err))
except pymongo.errors.OperationFailure, err:
message = 'Could not save document (%s)'
if re.match('^E1100[01] duplicate key', unicode(err)):
# E11000 - duplicate key error index
# E11001 - duplicate key on update
message = u'Tried to save duplicate unique keys (%s)'
raise NotUniqueError(message % unicode(err))
raise OperationError(message % unicode(err))
id_field = self._meta['id_field']
if created or id_field not in self._meta.get('shard_key', []):
self[id_field] = self._fields[id_field].to_python(object_id)
signals.post_save.send(self.__class__, document=self, created=created)
self._clear_changed_fields()
self._created = False
return self
def cascade_save(self, *args, **kwargs):
"""Recursively saves any references /
generic references on an objects"""
_refs = kwargs.get('_refs', []) or []
ReferenceField = _import_class('ReferenceField')
GenericReferenceField = _import_class('GenericReferenceField')
for name, cls in self._fields.items():
if not isinstance(cls, (ReferenceField,
GenericReferenceField)):
continue
ref = self._data.get(name)
if not ref or isinstance(ref, DBRef):
continue
if not getattr(ref, '_changed_fields', True):
continue
ref_id = "%s,%s" % (ref.__class__.__name__, str(ref._data))
if ref and ref_id not in _refs:
_refs.append(ref_id)
kwargs["_refs"] = _refs
ref.save(**kwargs)
ref._changed_fields = []
@property
def _qs(self):
"""
Returns the queryset to use for updating / reloading / deletions
"""
if not hasattr(self, '__objects'):
self.__objects = QuerySet(self, self._get_collection())
return self.__objects
@property
def _object_key(self):
"""Dict to identify object in collection
"""
select_dict = {'pk': self.pk}
shard_key = self.__class__._meta.get('shard_key', tuple())
for k in shard_key:
select_dict[k] = getattr(self, k)
return select_dict
def update(self, **kwargs):
"""Performs an update on the :class:`~mongoengine.Document`
A convenience wrapper to :meth:`~mongoengine.QuerySet.update`.
Raises :class:`OperationError` if called on an object that has not yet
been saved.
"""
if not self.pk:
if kwargs.get('upsert', False):
query = self.to_mongo()
if "_cls" in query:
del(query["_cls"])
return self._qs.filter(**query).update_one(**kwargs)
else:
raise OperationError(
'attempt to update a document not yet saved')
# Need to add shard key to query, or you get an error
return self._qs.filter(**self._object_key).update_one(**kwargs)
def delete(self, **write_concern):
"""Delete the :class:`~mongoengine.Document` from the database. This
will only take effect if the document has been previously saved.
: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.
"""
signals.pre_delete.send(self.__class__, document=self)
# Delete FileFields separately
FileField = _import_class('FileField')
for name, field in self._fields.iteritems():
if isinstance(field, FileField):
getattr(self, name).delete()
try:
self._qs.filter(
**self._object_key).delete(write_concern=write_concern, _from_doc_delete=True)
except pymongo.errors.OperationFailure, err:
message = u'Could not delete document (%s)' % err.message
raise OperationError(message)
signals.post_delete.send(self.__class__, document=self)
def switch_db(self, db_alias, keep_created=True):
"""
Temporarily switch the database for a document instance.
Only really useful for archiving off data and calling `save()`::
user = User.objects.get(id=user_id)
user.switch_db('archive-db')
user.save()
:param str db_alias: The database alias to use for saving the document
:param bool keep_created: keep self._created value after switching db, else is reset to True
.. seealso::
Use :class:`~mongoengine.context_managers.switch_collection`
if you need to read from another collection
"""
with switch_db(self.__class__, db_alias) as cls:
collection = cls._get_collection()
db = cls._get_db()
self._get_collection = lambda: collection
self._get_db = lambda: db
self._collection = collection
self._created = True if not keep_created else self._created
self.__objects = self._qs
self.__objects._collection_obj = collection
return self
def switch_collection(self, collection_name, keep_created=True):
"""
Temporarily switch the collection for a document instance.
Only really useful for archiving off data and calling `save()`::
user = User.objects.get(id=user_id)
user.switch_collection('old-users')
user.save()
:param str collection_name: The database alias to use for saving the
document
:param bool keep_created: keep self._created value after switching collection, else is reset to True
.. seealso::
Use :class:`~mongoengine.context_managers.switch_db`
if you need to read from another database
"""
with switch_collection(self.__class__, collection_name) as cls:
collection = cls._get_collection()
self._get_collection = lambda: collection
self._collection = collection
self._created = True if not keep_created else self._created
self.__objects = self._qs
self.__objects._collection_obj = collection
return self
def select_related(self, max_depth=1):
"""Handles dereferencing of :class:`~bson.dbref.DBRef` objects to
a maximum depth in order to cut down the number queries to mongodb.
.. versionadded:: 0.5
"""
DeReference = _import_class('DeReference')
DeReference()([self], max_depth + 1)
return self
def reload(self, *fields, **kwargs):
"""Reloads all attributes from the database.
:param fields: (optional) args list of fields to reload
:param max_depth: (optional) depth of dereferencing to follow
.. versionadded:: 0.1.2
.. versionchanged:: 0.6 Now chainable
.. versionchanged:: 0.9 Can provide specific fields to reload
"""
max_depth = 1
if fields and isinstance(fields[0], int):
max_depth = fields[0]
fields = fields[1:]
elif "max_depth" in kwargs:
max_depth = kwargs["max_depth"]
if not self.pk:
raise self.DoesNotExist("Document does not exist")
obj = self._qs.read_preference(ReadPreference.PRIMARY).filter(
**self._object_key).only(*fields).limit(1
).select_related(max_depth=max_depth)
if obj:
obj = obj[0]
else:
raise self.DoesNotExist("Document does not exist")
for field in self._fields_ordered:
if not fields or field in fields:
try:
setattr(self, field, self._reload(field, obj[field]))
except KeyError:
# If field is removed from the database while the object
# is in memory, a reload would cause a KeyError
# i.e. obj.update(unset__field=1) followed by obj.reload()
delattr(self, field)
self._changed_fields = obj._changed_fields
self._created = False
return self
def _reload(self, key, value):
"""Used by :meth:`~mongoengine.Document.reload` to ensure the
correct instance is linked to self.
"""
if isinstance(value, BaseDict):
value = [(k, self._reload(k, v)) for k, v in value.items()]
value = BaseDict(value, self, key)
elif isinstance(value, EmbeddedDocumentList):
value = [self._reload(key, v) for v in value]
value = EmbeddedDocumentList(value, self, key)
elif isinstance(value, BaseList):
value = [self._reload(key, v) for v in value]
value = BaseList(value, self, key)
elif isinstance(value, (EmbeddedDocument, DynamicEmbeddedDocument)):
value._instance = None
value._changed_fields = []
return value
def to_dbref(self):
"""Returns an instance of :class:`~bson.dbref.DBRef` useful in
`__raw__` queries."""
if not self.pk:
msg = "Only saved documents can have a valid dbref"
raise OperationError(msg)
return DBRef(self.__class__._get_collection_name(), self.pk)
@classmethod
def register_delete_rule(cls, document_cls, field_name, rule):
"""This method registers the delete rules to apply when removing this
object.
"""
classes = [get_document(class_name)
for class_name in cls._subclasses
if class_name != cls.__name__] + [cls]
documents = [get_document(class_name)
for class_name in document_cls._subclasses
if class_name != document_cls.__name__] + [document_cls]
for cls in classes:
for document_cls in documents:
delete_rules = cls._meta.get('delete_rules') or {}
delete_rules[(document_cls, field_name)] = rule
cls._meta['delete_rules'] = delete_rules
@classmethod
def drop_collection(cls):
"""Drops the entire collection associated with this
:class:`~mongoengine.Document` type from the database.
"""
cls._collection = None
db = cls._get_db()
db.drop_collection(cls._get_collection_name())
@classmethod
def create_index(cls, keys, background=False, **kwargs):
"""Creates the given indexes if required.
:param keys: a single index key or a list of index keys (to
construct a multi-field index); keys may be prefixed with a **+**
or a **-** to determine the index ordering
:param background: Allows index creation in the background
"""
index_spec = cls._build_index_spec(keys)
index_spec = index_spec.copy()
fields = index_spec.pop('fields')
drop_dups = kwargs.get('drop_dups', False)
if IS_PYMONGO_3 and drop_dups:
msg = "drop_dups is deprecated and is removed when using PyMongo 3+."
warnings.warn(msg, DeprecationWarning)
elif not IS_PYMONGO_3:
index_spec['drop_dups'] = drop_dups
index_spec['background'] = background
index_spec.update(kwargs)
if IS_PYMONGO_3:
return cls._get_collection().create_index(fields, **index_spec)
else:
return cls._get_collection().ensure_index(fields, **index_spec)
@classmethod
def ensure_index(cls, key_or_list, drop_dups=False, background=False,
**kwargs):
"""Ensure that the given indexes are in place. Deprecated in favour
of create_index.
:param key_or_list: a single index key or a list of index keys (to
construct a multi-field index); keys may be prefixed with a **+**
or a **-** to determine the index ordering
:param background: Allows index creation in the background
:param drop_dups: Was removed/ignored with MongoDB >2.7.5. The value
will be removed if PyMongo3+ is used
"""
if IS_PYMONGO_3 and drop_dups:
msg = "drop_dups is deprecated and is removed when using PyMongo 3+."
warnings.warn(msg, DeprecationWarning)
elif not IS_PYMONGO_3:
kwargs.update({'drop_dups': drop_dups})
return cls.create_index(key_or_list, background=background, **kwargs)
@classmethod
def ensure_indexes(cls):
"""Checks the document meta data and ensures all the indexes exist.
Global defaults can be set in the meta - see :doc:`guide/defining-documents`
.. note:: You can disable automatic index creation by setting
`auto_create_index` to False in the documents meta data
"""
background = cls._meta.get('index_background', False)
drop_dups = cls._meta.get('index_drop_dups', False)
index_opts = cls._meta.get('index_opts') or {}
index_cls = cls._meta.get('index_cls', True)
if IS_PYMONGO_3 and drop_dups:
msg = "drop_dups is deprecated and is removed when using PyMongo 3+."
warnings.warn(msg, DeprecationWarning)
collection = cls._get_collection()
# 746: when connection is via mongos, the read preference is not necessarily an indication that
# this code runs on a secondary
if not collection.is_mongos and collection.read_preference > 1:
return
# determine if an index which we are creating includes
# _cls as its first field; if so, we can avoid creating
# an extra index on _cls, as mongodb will use the existing
# index to service queries against _cls
cls_indexed = False
# Ensure document-defined indexes are created
if cls._meta['index_specs']:
index_spec = cls._meta['index_specs']
for spec in index_spec:
spec = spec.copy()
fields = spec.pop('fields')
cls_indexed = cls_indexed or includes_cls(fields)
opts = index_opts.copy()
opts.update(spec)
# we shouldn't pass 'cls' to the collection.ensureIndex options
# because of https://jira.mongodb.org/browse/SERVER-769
if 'cls' in opts:
del opts['cls']
if IS_PYMONGO_3:
collection.create_index(fields, background=background, **opts)
else:
collection.ensure_index(fields, background=background,
drop_dups=drop_dups, **opts)
# If _cls is being used (for polymorphism), it needs an index,
# only if another index doesn't begin with _cls
if (index_cls and not cls_indexed and
cls._meta.get('allow_inheritance', ALLOW_INHERITANCE) is True):
# we shouldn't pass 'cls' to the collection.ensureIndex options
# because of https://jira.mongodb.org/browse/SERVER-769
if 'cls' in index_opts:
del index_opts['cls']
if IS_PYMONGO_3:
collection.create_index('_cls', background=background,
**index_opts)
else:
collection.ensure_index('_cls', background=background,
**index_opts)
@classmethod
def list_indexes(cls, go_up=True, go_down=True):
""" Lists all of the indexes that should be created for given
collection. It includes all the indexes from super- and sub-classes.
"""
if cls._meta.get('abstract'):
return []
# get all the base classes, subclasses and siblings
classes = []
def get_classes(cls):
if (cls not in classes and
isinstance(cls, TopLevelDocumentMetaclass)):
classes.append(cls)
for base_cls in cls.__bases__:
if (isinstance(base_cls, TopLevelDocumentMetaclass) and
base_cls != Document and
not base_cls._meta.get('abstract') and
base_cls._get_collection().full_name == cls._get_collection().full_name and
base_cls not in classes):
classes.append(base_cls)
get_classes(base_cls)
for subclass in cls.__subclasses__():
if (isinstance(base_cls, TopLevelDocumentMetaclass) and
subclass._get_collection().full_name == cls._get_collection().full_name and
subclass not in classes):
classes.append(subclass)
get_classes(subclass)
get_classes(cls)
# get the indexes spec for all of the gathered classes
def get_indexes_spec(cls):
indexes = []
if cls._meta['index_specs']:
index_spec = cls._meta['index_specs']
for spec in index_spec:
spec = spec.copy()
fields = spec.pop('fields')
indexes.append(fields)
return indexes
indexes = []
for cls in classes:
for index in get_indexes_spec(cls):
if index not in indexes:
indexes.append(index)
# finish up by appending { '_id': 1 } and { '_cls': 1 }, if needed
if [(u'_id', 1)] not in indexes:
indexes.append([(u'_id', 1)])
if (cls._meta.get('index_cls', True) and
cls._meta.get('allow_inheritance', ALLOW_INHERITANCE) is True):
indexes.append([(u'_cls', 1)])
return indexes
@classmethod
def compare_indexes(cls):
""" Compares the indexes defined in MongoEngine with the ones existing
in the database. Returns any missing/extra indexes.
"""
required = cls.list_indexes()
existing = [info['key']
for info in cls._get_collection().index_information().values()]
missing = [index for index in required if index not in existing]
extra = [index for index in existing if index not in required]
# if { _cls: 1 } is missing, make sure it's *really* necessary
if [(u'_cls', 1)] in missing:
cls_obsolete = False
for index in existing:
if includes_cls(index) and index not in extra:
cls_obsolete = True
break
if cls_obsolete:
missing.remove([(u'_cls', 1)])
return {'missing': missing, 'extra': extra}
class DynamicDocument(Document):
"""A Dynamic Document class allowing flexible, expandable and uncontrolled
schemas. As a :class:`~mongoengine.Document` subclass, acts in the same
way as an ordinary document but has expando style properties. Any data
passed or set against the :class:`~mongoengine.DynamicDocument` that is
not a field is automatically converted into a
:class:`~mongoengine.fields.DynamicField` and data can be attributed to that
field.
.. note::
There is one caveat on Dynamic Documents: fields cannot start with `_`
"""
# The __metaclass__ attribute is removed by 2to3 when running with Python3
# my_metaclass is defined so that metaclass can be queried in Python 2 & 3
my_metaclass = TopLevelDocumentMetaclass
__metaclass__ = TopLevelDocumentMetaclass
_dynamic = True
def __delattr__(self, *args, **kwargs):
"""Deletes the attribute by setting to None and allowing _delta to unset
it"""
field_name = args[0]
if field_name in self._dynamic_fields:
setattr(self, field_name, None)
else:
super(DynamicDocument, self).__delattr__(*args, **kwargs)
class DynamicEmbeddedDocument(EmbeddedDocument):
"""A Dynamic Embedded Document class allowing flexible, expandable and
uncontrolled schemas. See :class:`~mongoengine.DynamicDocument` for more
information about dynamic documents.
"""
# The __metaclass__ attribute is removed by 2to3 when running with Python3
# my_metaclass is defined so that metaclass can be queried in Python 2 & 3
my_metaclass = DocumentMetaclass
__metaclass__ = DocumentMetaclass
_dynamic = True
def __delattr__(self, *args, **kwargs):
"""Deletes the attribute by setting to None and allowing _delta to unset
it"""
field_name = args[0]
if field_name in self._fields:
default = self._fields[field_name].default
if callable(default):
default = default()
setattr(self, field_name, default)
else:
setattr(self, field_name, None)
class MapReduceDocument(object):
"""A document returned from a map/reduce query.
:param collection: An instance of :class:`~pymongo.Collection`
:param key: Document/result key, often an instance of
:class:`~bson.objectid.ObjectId`. If supplied as
an ``ObjectId`` found in the given ``collection``,
the object can be accessed via the ``object`` property.
:param value: The result(s) for this key.
.. versionadded:: 0.3
"""
def __init__(self, document, collection, key, value):
self._document = document
self._collection = collection
self.key = key
self.value = value
@property
def object(self):
"""Lazy-load the object referenced by ``self.key``. ``self.key``
should be the ``primary_key``.
"""
id_field = self._document()._meta['id_field']
id_field_type = type(id_field)
if not isinstance(self.key, id_field_type):
try:
self.key = id_field_type(self.key)
except:
raise Exception("Could not cast key as %s" %
id_field_type.__name__)
if not hasattr(self, "_key_object"):
self._key_object = self._document.objects.with_id(self.key)
return self._key_object
return self._key_object