Merge remote branch 'upstream/dev' into dev

AUTHORS

@@ -3,3 +3,4 @@ Matt Dennewitz <mattdennewitz@gmail.com>
 Deepak Thukral <iapain@yahoo.com>
 Florian Schlachter <flori@n-schlachter.de>
 Steve Challis <steve@stevechallis.com>
+Ross Lawley <ross.lawley@gmail.com>

docs/changelog.rst

@@ -5,6 +5,11 @@ Changelog
 Changes in dev
 ==============
 
+- Added slave_okay kwarg to queryset
+- Added insert method for bulk inserts
+- Added blinker signal support
+- Added query_counter context manager for tests
+- Added DereferenceBaseField - for improved performance in field dereferencing
 - Added optional map_reduce method item_frequencies
 - Added inline_map_reduce option to map_reduce
 - Updated connection exception so it provides more info on the cause.

docs/django.rst

@@ -49,10 +49,11 @@ Storage
 =======
 With MongoEngine's support for GridFS via the :class:`~mongoengine.FileField`,
 it is useful to have a Django file storage backend that wraps this. The new
-storage module is called :class:`~mongoengine.django.GridFSStorage`. Using it
+storage module is called :class:`~mongoengine.django.storage.GridFSStorage`. 
-is very similar to using the default FileSystemStorage.::
+Using it is very similar to using the default FileSystemStorage.::
     
-    fs = mongoengine.django.GridFSStorage()
+    from mongoengine.django.storage import GridFSStorage
+    fs = GridFSStorage()
 
     filename = fs.save('hello.txt', 'Hello, World!')
 

docs/guide/defining-documents.rst

@@ -341,9 +341,10 @@ Indexes
 You can specify indexes on collections to make querying faster. This is done
 by creating a list of index specifications called :attr:`indexes` in the
 :attr:`~mongoengine.Document.meta` dictionary, where an index specification may
-either be a single field name, or a tuple containing multiple field names. A
+either be a single field name, a tuple containing multiple field names, or a
-direction may be specified on fields by prefixing the field name with a **+**
+dictionary containing a full index definition. A direction may be specified on
-or a **-** sign. Note that direction only matters on multi-field indexes. ::
+fields by prefixing the field name with a **+** or a **-** sign. Note that
+direction only matters on multi-field indexes. ::
 
     class Page(Document):
         title = StringField()
@@ -352,6 +353,21 @@ or a **-** sign. Note that direction only matters on multi-field indexes. ::
             'indexes': ['title', ('title', '-rating')]
         }
 
+If a dictionary is passed then the following options are available:
+
+:attr:`fields` (Default: None)
+    The fields to index. Specified in the same format as described above.
+
+:attr:`types` (Default: True)
+    Whether the index should have the :attr:`_types` field added automatically
+    to the start of the index.
+
+:attr:`sparse` (Default: False)
+    Whether the index should be sparse.
+
+:attr:`unique` (Default: False)
+    Whether the index should be sparse.
+
 .. note::
    Geospatial indexes will be automatically created for all 
    :class:`~mongoengine.GeoPointField`\ s

docs/guide/index.rst

@@ -11,3 +11,4 @@ User Guide
    document-instances
    querying
    gridfs
+   signals

docs/guide/signals.rst

@@ -0,0 +1,49 @@
+.. _signals:
+
+Signals
+=======
+
+.. versionadded:: 0.5
+
+Signal support is provided by the excellent `blinker`_ library and
+will gracefully fall back if it is not available.
+
+
+The following document signals exist in MongoEngine and are pretty self explaintary:
+
+  * `mongoengine.signals.pre_init`
+  * `mongoengine.signals.post_init`
+  * `mongoengine.signals.pre_save`
+  * `mongoengine.signals.post_save`
+  * `mongoengine.signals.pre_delete`
+  * `mongoengine.signals.post_delete`
+
+Example usage::
+
+    from mongoengine import *
+    from mongoengine import signals
+
+    class Author(Document):
+        name = StringField()
+
+        def __unicode__(self):
+            return self.name
+
+        @classmethod
+        def pre_save(cls, instance, **kwargs):
+            logging.debug("Pre Save: %s" % instance.name)
+
+        @classmethod
+        def post_save(cls, instance, **kwargs):
+            logging.debug("Post Save: %s" % instance.name)
+            if 'created' in kwargs:
+                if kwargs['created']:
+                    logging.debug("Created")
+                else:
+                    logging.debug("Updated")
+        
+        signals.pre_save.connect(Author.pre_save)
+        signals.post_save.connect(Author.post_save)
+
+
+.. _blinker: http://pypi.python.org/pypi/blinker

mongoengine/__init__.py

@@ -6,9 +6,11 @@ import connection
 from connection import *
 import queryset
 from queryset import *
+import signals
+from signals import *
 
 __all__ = (document.__all__ + fields.__all__ + connection.__all__ +
-           queryset.__all__)
+           queryset.__all__ + signals.__all__)
 
 __author__ = 'Harry Marr'
 

mongoengine/base.py

@@ -2,9 +2,12 @@ from queryset import QuerySet, QuerySetManager
 from queryset import DoesNotExist, MultipleObjectsReturned
 from queryset import DO_NOTHING
 
+from mongoengine import signals
+
 import sys
 import pymongo
 import pymongo.objectid
+from operator import itemgetter
 
 
 class NotRegistered(Exception):
@@ -126,6 +129,88 @@ class BaseField(object):
 
         self.validate(value)
 
+
+class DereferenceBaseField(BaseField):
+    """Handles the lazy dereferencing of a queryset.  Will dereference all
+    items in a list / dict rather than one at a time.
+    """
+
+    def __get__(self, instance, owner):
+        """Descriptor to automatically dereference references.
+        """
+        from fields import ReferenceField, GenericReferenceField
+        from connection import _get_db
+
+        if instance is None:
+            # Document class being used rather than a document object
+            return self
+
+        # Get value from document instance if available
+        value_list = instance._data.get(self.name)
+        if not value_list:
+            return super(DereferenceBaseField, self).__get__(instance, owner)
+
+        is_list = False
+        if not hasattr(value_list, 'items'):
+            is_list = True
+            value_list = dict([(k,v) for k,v in enumerate(value_list)])
+
+        if isinstance(self.field, ReferenceField) and value_list:
+            db = _get_db()
+            dbref = {}
+            collections = {}
+
+            for k, v in value_list.items():
+                dbref[k] = v
+                # Save any DBRefs
+                if isinstance(v, (pymongo.dbref.DBRef)):
+                    collections.setdefault(v.collection, []).append((k, v))
+
+            # For each collection get the references
+            for collection, dbrefs in collections.items():
+                id_map = dict([(v.id, k) for k, v in dbrefs])
+                references = db[collection].find({'_id': {'$in': id_map.keys()}})
+                for ref in references:
+                    key = id_map[ref['_id']]
+                    dbref[key] = get_document(ref['_cls'])._from_son(ref)
+
+            if is_list:
+                dbref = [v for k,v in sorted(dbref.items(), key=itemgetter(0))]
+            instance._data[self.name] = dbref
+
+        # Get value from document instance if available
+        if isinstance(self.field, GenericReferenceField) and value_list:
+            db = _get_db()
+            value_list = [(k,v) for k,v in value_list.items()]
+            dbref = {}
+            classes = {}
+
+            for k, v in value_list:
+                dbref[k] = v
+                # Save any DBRefs
+                if isinstance(v, (dict, pymongo.son.SON)):
+                    classes.setdefault(v['_cls'], []).append((k, v))
+
+            # For each collection get the references
+            for doc_cls, dbrefs in classes.items():
+                id_map = dict([(v['_ref'].id, k) for k, v in dbrefs])
+                doc_cls = get_document(doc_cls)
+                collection = doc_cls._meta['collection']
+                references = db[collection].find({'_id': {'$in': id_map.keys()}})
+
+                for ref in references:
+                    key = id_map[ref['_id']]
+                    dbref[key] = doc_cls._from_son(ref)
+
+            if is_list:
+                dbref = [v for k,v in sorted(dbref.items(), key=itemgetter(0))]
+
+            instance._data[self.name] = dbref
+
+        return super(DereferenceBaseField, self).__get__(instance, owner)
+
+
+
 class ObjectIdField(BaseField):
     """An field wrapper around MongoDB's ObjectIds.
     """
@@ -382,6 +467,8 @@ class TopLevelDocumentMetaclass(DocumentMetaclass):
 class BaseDocument(object):
 
     def __init__(self, **values):
+        signals.pre_init.send(self, values=values)
+
         self._data = {}
         # Assign default values to instance
         for attr_name in self._fields.keys():
@@ -395,6 +482,8 @@ class BaseDocument(object):
             except AttributeError:
                 pass
 
+        signals.post_init.send(self)
+
     def validate(self):
         """Ensure that all fields' values are valid and that required fields
         are present.

mongoengine/document.py

@@ -1,3 +1,4 @@
+from mongoengine import signals
 from base import (DocumentMetaclass, TopLevelDocumentMetaclass, BaseDocument,
                   ValidationError)
 from queryset import OperationError
@@ -75,6 +76,8 @@ class Document(BaseDocument):
                 For example, ``save(..., w=2, fsync=True)`` will wait until at least two servers
                 have recorded the write and will force an fsync on each server being written to.
         """
+        signals.pre_save.send(self)
+
         if validate:
             self.validate()
 
@@ -82,6 +85,7 @@ class Document(BaseDocument):
             write_options = {}
 
         doc = self.to_mongo()
+        created = '_id' not in doc
         try:
             collection = self.__class__.objects._collection
             if force_insert:
@@ -96,12 +100,16 @@ class Document(BaseDocument):
         id_field = self._meta['id_field']
         self[id_field] = self._fields[id_field].to_python(object_id)
 
+        signals.post_save.send(self, created=created)
+
     def delete(self, safe=False):
         """Delete the :class:`~mongoengine.Document` from the database. This
         will only take effect if the document has been previously saved.
 
         :param safe: check if the operation succeeded before returning
         """
+        signals.pre_delete.send(self)
+
         id_field = self._meta['id_field']
         object_id = self._fields[id_field].to_mongo(self[id_field])
         try:
@@ -110,6 +118,8 @@ class Document(BaseDocument):
             message = u'Could not delete document (%s)' % err.message
             raise OperationError(message)
 
+        signals.post_delete.send(self)
+
     @classmethod
     def register_delete_rule(cls, document_cls, field_name, rule):
         """This method registers the delete rules to apply when removing this

mongoengine/fields.py

@@ -1,4 +1,5 @@
-from base import BaseField, ObjectIdField, ValidationError, get_document
+from base import (BaseField, DereferenceBaseField, ObjectIdField,
+                  ValidationError, get_document)
 from queryset import DO_NOTHING
 from document import Document, EmbeddedDocument
 from connection import _get_db
@@ -12,7 +13,6 @@ import pymongo.binary
 import datetime, time
 import decimal
 import gridfs
-import warnings
 
 
 __all__ = ['StringField', 'IntField', 'FloatField', 'BooleanField',
@@ -118,8 +118,8 @@ class EmailField(StringField):
 
     EMAIL_REGEX = re.compile(
         r"(^[-!#$%&'*+/=?^_`{}|~0-9A-Z]+(\.[-!#$%&'*+/=?^_`{}|~0-9A-Z]+)*"  # dot-atom
-        r'|^"([\001-\010\013\014\016-\037!#-\[\]-\177]|\\[\001-011\013\014\016-\177])*"' # quoted-string
+        r'|^"([\001-\010\013\014\016-\037!#-\[\]-\177]|\\[\001-011\013\014\016-\177])*"'  # quoted-string
-        r')@(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+[A-Z]{2,6}\.?$', re.IGNORECASE # domain
+        r')@(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+[A-Z]{2,6}\.?$', re.IGNORECASE  # domain
     )
 
     def validate(self, value):
@@ -153,6 +153,7 @@ class IntField(BaseField):
     def prepare_query_value(self, op, value):
         return int(value)
 
+
 class FloatField(BaseField):
     """An floating point number field.
     """
@@ -178,6 +179,7 @@ class FloatField(BaseField):
     def prepare_query_value(self, op, value):
         return float(value)
 
+
 class DecimalField(BaseField):
     """A fixed-point decimal number field.
 
@@ -227,6 +229,10 @@ class BooleanField(BaseField):
 
 class DateTimeField(BaseField):
     """A datetime field.
+
+    Note: Microseconds are rounded to the nearest millisecond.
+      Pre UTC microsecond support is effecively broken see
+      `tests.field.test_datetime` for more information.
     """
 
     def validate(self, value):
@@ -252,21 +258,21 @@ class DateTimeField(BaseField):
         else:
             usecs = 0
         kwargs = {'microsecond': usecs}
-        try: # Seconds are optional, so try converting seconds first.
+        try:  # Seconds are optional, so try converting seconds first.
             return datetime.datetime(*time.strptime(value, '%Y-%m-%d %H:%M:%S')[:6],
                                      **kwargs)
-
         except ValueError:
-            try: # Try without seconds.
+            try:  # Try without seconds.
                 return datetime.datetime(*time.strptime(value, '%Y-%m-%d %H:%M')[:5],
                                          **kwargs)
-            except ValueError: # Try without hour/minutes/seconds.
+            except ValueError:  # Try without hour/minutes/seconds.
                 try:
                     return datetime.datetime(*time.strptime(value, '%Y-%m-%d')[:3],
                                              **kwargs)
                 except ValueError:
                     return None
 
+
 class EmbeddedDocumentField(BaseField):
     """An embedded document field. Only valid values are subclasses of
     :class:`~mongoengine.EmbeddedDocument`.
@@ -314,7 +320,7 @@ class EmbeddedDocumentField(BaseField):
         return self.to_mongo(value)
 
 
-class ListField(BaseField):
+class ListField(DereferenceBaseField):
     """A list field that wraps a standard field, allowing multiple instances
     of the field to be used as a list in the database.
     """
@@ -330,42 +336,6 @@ class ListField(BaseField):
         kwargs.setdefault('default', lambda: [])
         super(ListField, self).__init__(**kwargs)
 
-    def __get__(self, instance, owner):
-        """Descriptor to automatically dereference references.
-        """
-        if instance is None:
-            # Document class being used rather than a document object
-            return self
-
-        if isinstance(self.field, ReferenceField):
-            referenced_type = self.field.document_type
-            # Get value from document instance if available
-            value_list = instance._data.get(self.name)
-            if value_list:
-                deref_list = []
-                for value in value_list:
-                    # Dereference DBRefs
-                    if isinstance(value, (pymongo.dbref.DBRef)):
-                        value = _get_db().dereference(value)
-                        deref_list.append(referenced_type._from_son(value))
-                    else:
-                        deref_list.append(value)
-                instance._data[self.name] = deref_list
-
-        if isinstance(self.field, GenericReferenceField):
-            value_list = instance._data.get(self.name)
-            if value_list:
-                deref_list = []
-                for value in value_list:
-                    # Dereference DBRefs
-                    if isinstance(value, (dict, pymongo.son.SON)):
-                        deref_list.append(self.field.dereference(value))
-                    else:
-                        deref_list.append(value)
-                instance._data[self.name] = deref_list
-
-        return super(ListField, self).__get__(instance, owner)
-
     def to_python(self, value):
         return [self.field.to_python(item) for item in value]
 
@@ -459,10 +429,10 @@ class DictField(BaseField):
         if op in match_operators and isinstance(value, basestring):
             return StringField().prepare_query_value(op, value)
 
-        return super(DictField,self).prepare_query_value(op, value)
+        return super(DictField, self).prepare_query_value(op, value)
 
 
-class MapField(BaseField):
+class MapField(DereferenceBaseField):
     """A field that maps a name to a specified field type. Similar to
     a DictField, except the 'value' of each item must match the specified
     field type.
@@ -494,47 +464,11 @@ class MapField(BaseField):
         except Exception, err:
             raise ValidationError('Invalid MapField item (%s)' % str(item))
 
-    def __get__(self, instance, owner):
-        """Descriptor to automatically dereference references.
-        """
-        if instance is None:
-            # Document class being used rather than a document object
-            return self
-
-        if isinstance(self.field, ReferenceField):
-            referenced_type = self.field.document_type
-            # Get value from document instance if available
-            value_dict = instance._data.get(self.name)
-            if value_dict:
-                deref_dict = []
-                for key,value in value_dict.iteritems():
-                    # Dereference DBRefs
-                    if isinstance(value, (pymongo.dbref.DBRef)):
-                        value = _get_db().dereference(value)
-                        deref_dict[key] = referenced_type._from_son(value)
-                    else:
-                        deref_dict[key] = value
-                instance._data[self.name] = deref_dict
-
-        if isinstance(self.field, GenericReferenceField):
-            value_dict = instance._data.get(self.name)
-            if value_dict:
-                deref_dict = []
-                for key,value in value_dict.iteritems():
-                    # Dereference DBRefs
-                    if isinstance(value, (dict, pymongo.son.SON)):
-                        deref_dict[key] = self.field.dereference(value)
-                    else:
-                        deref_dict[key] = value
-                instance._data[self.name] = deref_dict
-
-        return super(MapField, self).__get__(instance, owner)
-
     def to_python(self, value):
-        return dict( [(key,self.field.to_python(item)) for key,item in value.iteritems()] )
+        return dict([(key, self.field.to_python(item)) for key, item in value.iteritems()])
 
     def to_mongo(self, value):
-        return dict( [(key,self.field.to_mongo(item)) for key,item in value.iteritems()] )
+        return dict([(key, self.field.to_mongo(item)) for key, item in value.iteritems()])
 
     def prepare_query_value(self, op, value):
         if op not in ('set', 'unset'):
@@ -752,11 +686,11 @@ class GridFSProxy(object):
         self.newfile = self.fs.new_file(**kwargs)
         self.grid_id = self.newfile._id
 
-    def put(self, file, **kwargs):
+    def put(self, file_obj, **kwargs):
         if self.grid_id:
             raise GridFSError('This document already has a file. Either delete '
                               'it or call replace to overwrite it')
-        self.grid_id = self.fs.put(file, **kwargs)
+        self.grid_id = self.fs.put(file_obj, **kwargs)
 
     def write(self, string):
         if self.grid_id:
@@ -785,9 +719,9 @@ class GridFSProxy(object):
         self.grid_id = None
         self.gridout = None
 
-    def replace(self, file, **kwargs):
+    def replace(self, file_obj, **kwargs):
         self.delete()
-        self.put(file, **kwargs)
+        self.put(file_obj, **kwargs)
 
     def close(self):
         if self.newfile:

mongoengine/queryset.py

@@ -336,6 +336,7 @@ class QuerySet(object):
         self._snapshot = False
         self._timeout = True
         self._class_check = True
+        self._slave_okay = False
 
         # If inheritance is allowed, only return instances and instances of
         # subclasses of the class being used
@@ -352,7 +353,7 @@ class QuerySet(object):
 
         copy_props = ('_initial_query', '_query_obj', '_where_clause',
                     '_loaded_fields', '_ordering', '_snapshot',
-                    '_timeout', '_limit', '_skip')
+                    '_timeout', '_limit', '_skip', '_slave_okay')
 
         for prop in copy_props:
             val = getattr(self, prop)
@@ -376,21 +377,27 @@ class QuerySet(object):
             construct a multi-field index); keys may be prefixed with a **+**
             or a **-** to determine the index ordering
         """
-        index_list = QuerySet._build_index_spec(self._document, key_or_list)
+        index_spec = QuerySet._build_index_spec(self._document, key_or_list)
-        self._collection.ensure_index(index_list, drop_dups=drop_dups,
+        self._collection.ensure_index(
-            background=background)
+            index_spec['fields'],
+            drop_dups=drop_dups,
+            background=background,
+            sparse=index_spec.get('sparse', False),
+            unique=index_spec.get('unique', False))
         return self
 
     @classmethod
-    def _build_index_spec(cls, doc_cls, key_or_list):
+    def _build_index_spec(cls, doc_cls, spec):
         """Build a PyMongo index spec from a MongoEngine index spec.
         """
-        if isinstance(key_or_list, basestring):
+        if isinstance(spec, basestring):
-            key_or_list = [key_or_list]
+            spec = {'fields': [spec]}
+        if isinstance(spec, (list, tuple)):
+            spec = {'fields': spec}
 
         index_list = []
         use_types = doc_cls._meta.get('allow_inheritance', True)
-        for key in key_or_list:
+        for key in spec['fields']:
             # Get direction from + or -
             direction = pymongo.ASCENDING
             if key.startswith("-"):
@@ -411,12 +418,20 @@ class QuerySet(object):
                 use_types = False
 
         # If _types is being used, prepend it to every specified index
-        if doc_cls._meta.get('allow_inheritance') and use_types:
+        if (spec.get('types', True) and doc_cls._meta.get('allow_inheritance')
+                and use_types):
             index_list.insert(0, ('_types', 1))
 
-        return index_list
+        spec['fields'] = index_list
 
-    def __call__(self, q_obj=None, class_check=True, **query):
+        if spec.get('sparse', False) and len(spec['fields']) > 1:
+            raise ValueError(
+                'Sparse indexes can only have one field in them. '
+                'See https://jira.mongodb.org/browse/SERVER-2193')
+
+        return spec
+
+    def __call__(self, q_obj=None, class_check=True, slave_okay=False, **query):
         """Filter the selected documents by calling the
         :class:`~mongoengine.queryset.QuerySet` with a query.
 
@@ -426,6 +441,8 @@ class QuerySet(object):
             objects, only the last one will be used
         :param class_check: If set to False bypass class name check when
             querying collection
+        :param slave_okay: if True, allows this query to be run against a
+            replica secondary.
         :param query: Django-style query keyword arguments
         """
         query = Q(**query)
@@ -465,9 +482,12 @@ class QuerySet(object):
 
             # Ensure document-defined indexes are created
             if self._document._meta['indexes']:
-                for key_or_list in self._document._meta['indexes']:
+                for spec in self._document._meta['indexes']:
-                    self._collection.ensure_index(key_or_list,
+                    opts = index_opts.copy()
-                        background=background, **index_opts)
+                    opts['unique'] = spec.get('unique', False)
+                    opts['sparse'] = spec.get('sparse', False)
+                    self._collection.ensure_index(spec['fields'],
+                        background=background, **opts)
 
             # If _types is being used (for polymorphism), it needs an index
             if '_types' in self._query:
@@ -483,17 +503,23 @@ class QuerySet(object):
 
         return self._collection_obj
 
+    @property
+    def _cursor_args(self):
+        cursor_args = {
+            'snapshot': self._snapshot,
+            'timeout': self._timeout,
+            'slave_okay': self._slave_okay
+        }
+        if self._loaded_fields:
+            cursor_args['fields'] = self._loaded_fields.as_dict()
+        return cursor_args
+
     @property
     def _cursor(self):
         if self._cursor_obj is None:
-            cursor_args = {
+
-                'snapshot': self._snapshot,
-                'timeout': self._timeout,
-            }
-            if self._loaded_fields:
-                cursor_args['fields'] = self._loaded_fields.as_dict()
             self._cursor_obj = self._collection.find(self._query,
-                                                     **cursor_args)
+                                                     **self._cursor_args)
             # Apply where clauses to cursor
             if self._where_clause:
                 self._cursor_obj.where(self._where_clause)
@@ -702,6 +728,46 @@ class QuerySet(object):
             result = None
         return result
 
+    def insert(self, doc_or_docs, load_bulk=True):
+        """bulk insert documents
+
+        :param docs_or_doc: a document or list of documents to be inserted
+        :param load_bulk (optional): If True returns the list of document instances
+
+        By default returns document instances, set ``load_bulk`` to False to
+        return just ``ObjectIds``
+
+        .. versionadded:: 0.5
+        """
+        from document import Document
+
+        docs = doc_or_docs
+        return_one = False
+        if isinstance(docs, Document) or issubclass(docs.__class__, Document):
+            return_one = True
+            docs = [docs]
+
+        raw = []
+        for doc in docs:
+            if not isinstance(doc, self._document):
+                msg = "Some documents inserted aren't instances of %s" % str(self._document)
+                raise OperationError(msg)
+            if doc.pk:
+                msg = "Some documents have ObjectIds use doc.update() instead"
+                raise OperationError(msg)
+            raw.append(doc.to_mongo())
+
+        ids = self._collection.insert(raw)
+
+        if not load_bulk:
+            return return_one and ids[0] or ids
+
+        documents = self.in_bulk(ids)
+        results = []
+        for obj_id in ids:
+            results.append(documents.get(obj_id))
+        return return_one and results[0] or results
+
     def with_id(self, object_id):
         """Retrieve the object matching the id provided.
 
@@ -710,7 +776,7 @@ class QuerySet(object):
         id_field = self._document._meta['id_field']
         object_id = self._document._fields[id_field].to_mongo(object_id)
 
-        result = self._collection.find_one({'_id': object_id})
+        result = self._collection.find_one({'_id': object_id}, **self._cursor_args)
         if result is not None:
             result = self._document._from_son(result)
         return result
@@ -726,7 +792,8 @@ class QuerySet(object):
         """
         doc_map = {}
 
-        docs = self._collection.find({'_id': {'$in': object_ids}})
+        docs = self._collection.find({'_id': {'$in': object_ids}},
+                                     **self._cursor_args)
         for doc in docs:
             doc_map[doc['_id']] = self._document._from_son(doc)
 
@@ -1023,6 +1090,7 @@ class QuerySet(object):
         :param enabled: whether or not snapshot mode is enabled
         """
         self._snapshot = enabled
+        return self
 
     def timeout(self, enabled):
         """Enable or disable the default mongod timeout when querying.
@@ -1030,6 +1098,15 @@ class QuerySet(object):
         :param enabled: whether or not the timeout is used
         """
         self._timeout = enabled
+        return self
+
+    def slave_okay(self, enabled):
+        """Enable or disable the slave_okay when querying.
+
+        :param enabled: whether or not the slave_okay is enabled
+        """
+        self._slave_okay = enabled
+        return self
 
     def delete(self, safe=False):
         """Delete the documents matched by the query.

mongoengine/signals.py

@@ -0,0 +1,44 @@
+# -*- coding: utf-8 -*-
+
+__all__ = ['pre_init', 'post_init', 'pre_save', 'post_save',
+           'pre_delete', 'post_delete']
+
+signals_available = False
+try:
+    from blinker import Namespace
+    signals_available = True
+except ImportError:
+    class Namespace(object):
+        def signal(self, name, doc=None):
+            return _FakeSignal(name, doc)
+
+    class _FakeSignal(object):
+        """If blinker is unavailable, create a fake class with the same
+        interface that allows sending of signals but will fail with an
+        error on anything else.  Instead of doing anything on send, it
+        will just ignore the arguments and do nothing instead.
+        """
+
+        def __init__(self, name, doc=None):
+            self.name = name
+            self.__doc__ = doc
+
+        def _fail(self, *args, **kwargs):
+            raise RuntimeError('signalling support is unavailable '
+                               'because the blinker library is '
+                               'not installed.')
+        send = lambda *a, **kw: None
+        connect = disconnect = has_receivers_for = receivers_for = \
+            temporarily_connected_to = _fail
+        del _fail
+
+# the namespace for code signals.  If you are not mongoengine code, do
+# not put signals in here.  Create your own namespace instead.
+_signals = Namespace()
+
+pre_init = _signals.signal('pre_init')
+post_init = _signals.signal('post_init')
+pre_save = _signals.signal('pre_save')
+post_save = _signals.signal('post_save')
+pre_delete = _signals.signal('pre_delete')
+post_delete = _signals.signal('post_delete')

mongoengine/tests.py

@@ -0,0 +1,59 @@
+from mongoengine.connection import _get_db
+
+
+class query_counter(object):
+    """ Query_counter contextmanager to get the number of queries. """
+
+    def __init__(self):
+        """ Construct the query_counter. """
+        self.counter = 0
+        self.db = _get_db()
+
+    def __enter__(self):
+        """ On every with block we need to drop the profile collection. """
+        self.db.set_profiling_level(0)
+        self.db.system.profile.drop()
+        self.db.set_profiling_level(2)
+        return self
+
+    def __exit__(self, t, value, traceback):
+        """ Reset the profiling level. """
+        self.db.set_profiling_level(0)
+
+    def __eq__(self, value):
+        """ == Compare querycounter. """
+        return value == self._get_count()
+
+    def __ne__(self, value):
+        """ != Compare querycounter. """
+        return not self.__eq__(value)
+
+    def __lt__(self, value):
+        """ < Compare querycounter. """
+        return self._get_count() < value
+
+    def __le__(self, value):
+        """ <= Compare querycounter. """
+        return self._get_count() <= value
+
+    def __gt__(self, value):
+        """ > Compare querycounter. """
+        return self._get_count() > value
+
+    def __ge__(self, value):
+        """ >= Compare querycounter. """
+        return self._get_count() >= value
+
+    def __int__(self):
+        """ int representation. """
+        return self._get_count()
+
+    def __repr__(self):
+        """ repr query_counter as the number of queries. """
+        return u"%s" % self._get_count()
+
+    def _get_count(self):
+        """ Get the number of queries. """
+        count = self.db.system.profile.find().count() - self.counter
+        self.counter += 1
+        return count

setup.py

@@ -45,6 +45,6 @@ setup(name='mongoengine',
       long_description=LONG_DESCRIPTION,
       platforms=['any'],
       classifiers=CLASSIFIERS,
-      install_requires=['pymongo'],
+      install_requires=['pymongo', 'blinker'],
       test_suite='tests',
 )

tests/dereference.py

@@ -0,0 +1,288 @@
+import unittest
+
+from mongoengine import *
+from mongoengine.connection import _get_db
+from mongoengine.tests import query_counter
+
+
+class FieldTest(unittest.TestCase):
+
+    def setUp(self):
+        connect(db='mongoenginetest')
+        self.db = _get_db()
+
+    def test_list_item_dereference(self):
+        """Ensure that DBRef items in ListFields are dereferenced.
+        """
+        class User(Document):
+            name = StringField()
+
+        class Group(Document):
+            members = ListField(ReferenceField(User))
+
+        User.drop_collection()
+        Group.drop_collection()
+
+        for i in xrange(1, 51):
+            user = User(name='user %s' % i)
+            user.save()
+
+        group = Group(members=User.objects)
+        group.save()
+
+        with query_counter() as q:
+            self.assertEqual(q, 0)
+
+            group_obj = Group.objects.first()
+            self.assertEqual(q, 1)
+
+            [m for m in group_obj.members]
+            self.assertEqual(q, 2)
+
+        User.drop_collection()
+        Group.drop_collection()
+
+    def test_recursive_reference(self):
+        """Ensure that ReferenceFields can reference their own documents.
+        """
+        class Employee(Document):
+            name = StringField()
+            boss = ReferenceField('self')
+            friends = ListField(ReferenceField('self'))
+
+        bill = Employee(name='Bill Lumbergh')
+        bill.save()
+
+        michael = Employee(name='Michael Bolton')
+        michael.save()
+
+        samir = Employee(name='Samir Nagheenanajar')
+        samir.save()
+
+        friends = [michael, samir]
+        peter = Employee(name='Peter Gibbons', boss=bill, friends=friends)
+        peter.save()
+
+        with query_counter() as q:
+            self.assertEqual(q, 0)
+
+            peter = Employee.objects.with_id(peter.id)
+            self.assertEqual(q, 1)
+
+            peter.boss
+            self.assertEqual(q, 2)
+
+            peter.friends
+            self.assertEqual(q, 3)
+
+    def test_generic_reference(self):
+
+        class UserA(Document):
+            name = StringField()
+
+        class UserB(Document):
+            name = StringField()
+
+        class UserC(Document):
+            name = StringField()
+
+        class Group(Document):
+            members = ListField(GenericReferenceField())
+
+        UserA.drop_collection()
+        UserB.drop_collection()
+        UserC.drop_collection()
+        Group.drop_collection()
+
+        members = []
+        for i in xrange(1, 51):
+            a = UserA(name='User A %s' % i)
+            a.save()
+
+            b = UserB(name='User B %s' % i)
+            b.save()
+
+            c = UserC(name='User C %s' % i)
+            c.save()
+
+            members += [a, b, c]
+
+        group = Group(members=members)
+        group.save()
+
+        with query_counter() as q:
+            self.assertEqual(q, 0)
+
+            group_obj = Group.objects.first()
+            self.assertEqual(q, 1)
+
+            [m for m in group_obj.members]
+            self.assertEqual(q, 4)
+
+            [m for m in group_obj.members]
+            self.assertEqual(q, 4)
+
+        UserA.drop_collection()
+        UserB.drop_collection()
+        UserC.drop_collection()
+        Group.drop_collection()
+
+    def test_map_field_reference(self):
+
+        class User(Document):
+            name = StringField()
+
+        class Group(Document):
+            members = MapField(ReferenceField(User))
+
+        User.drop_collection()
+        Group.drop_collection()
+
+        members = []
+        for i in xrange(1, 51):
+            user = User(name='user %s' % i)
+            user.save()
+            members.append(user)
+
+        group = Group(members=dict([(str(u.id), u) for u in members]))
+        group.save()
+
+        with query_counter() as q:
+            self.assertEqual(q, 0)
+
+            group_obj = Group.objects.first()
+            self.assertEqual(q, 1)
+
+            [m for m in group_obj.members]
+            self.assertEqual(q, 2)
+
+        User.drop_collection()
+        Group.drop_collection()
+
+    def ztest_generic_reference_dict_field(self):
+
+        class UserA(Document):
+            name = StringField()
+
+        class UserB(Document):
+            name = StringField()
+
+        class UserC(Document):
+            name = StringField()
+
+        class Group(Document):
+            members = DictField()
+
+        UserA.drop_collection()
+        UserB.drop_collection()
+        UserC.drop_collection()
+        Group.drop_collection()
+
+        members = []
+        for i in xrange(1, 51):
+            a = UserA(name='User A %s' % i)
+            a.save()
+
+            b = UserB(name='User B %s' % i)
+            b.save()
+
+            c = UserC(name='User C %s' % i)
+            c.save()
+
+            members += [a, b, c]
+
+        group = Group(members=dict([(str(u.id), u) for u in members]))
+        group.save()
+
+        with query_counter() as q:
+            self.assertEqual(q, 0)
+
+            group_obj = Group.objects.first()
+            self.assertEqual(q, 1)
+
+            [m for m in group_obj.members]
+            self.assertEqual(q, 4)
+
+            [m for m in group_obj.members]
+            self.assertEqual(q, 4)
+
+        group.members = {}
+        group.save()
+
+        with query_counter() as q:
+            self.assertEqual(q, 0)
+
+            group_obj = Group.objects.first()
+            self.assertEqual(q, 1)
+
+            [m for m in group_obj.members]
+            self.assertEqual(q, 1)
+
+        UserA.drop_collection()
+        UserB.drop_collection()
+        UserC.drop_collection()
+        Group.drop_collection()
+
+    def test_generic_reference_map_field(self):
+
+        class UserA(Document):
+            name = StringField()
+
+        class UserB(Document):
+            name = StringField()
+
+        class UserC(Document):
+            name = StringField()
+
+        class Group(Document):
+            members = MapField(GenericReferenceField())
+
+        UserA.drop_collection()
+        UserB.drop_collection()
+        UserC.drop_collection()
+        Group.drop_collection()
+
+        members = []
+        for i in xrange(1, 51):
+            a = UserA(name='User A %s' % i)
+            a.save()
+
+            b = UserB(name='User B %s' % i)
+            b.save()
+
+            c = UserC(name='User C %s' % i)
+            c.save()
+
+            members += [a, b, c]
+
+        group = Group(members=dict([(str(u.id), u) for u in members]))
+        group.save()
+
+        with query_counter() as q:
+            self.assertEqual(q, 0)
+
+            group_obj = Group.objects.first()
+            self.assertEqual(q, 1)
+
+            [m for m in group_obj.members]
+            self.assertEqual(q, 4)
+
+            [m for m in group_obj.members]
+            self.assertEqual(q, 4)
+
+        group.members = {}
+        group.save()
+
+        with query_counter() as q:
+            self.assertEqual(q, 0)
+
+            group_obj = Group.objects.first()
+            self.assertEqual(q, 1)
+
+            [m for m in group_obj.members]
+            self.assertEqual(q, 1)
+
+        UserA.drop_collection()
+        UserB.drop_collection()
+        UserC.drop_collection()
+        Group.drop_collection()

tests/document.py

@@ -377,6 +377,40 @@ class DocumentTest(unittest.TestCase):
 
         BlogPost.drop_collection()
 
+
+    def test_dictionary_indexes(self):
+        """Ensure that indexes are used when meta[indexes] contains dictionaries
+        instead of lists.
+        """
+        class BlogPost(Document):
+            date = DateTimeField(db_field='addDate', default=datetime.now)
+            category = StringField()
+            tags = ListField(StringField())
+            meta = {
+                'indexes': [
+                    { 'fields': ['-date'], 'unique': True,
+                      'sparse': True, 'types': False },
+                ],
+            }
+
+        BlogPost.drop_collection()
+
+        info = BlogPost.objects._collection.index_information()
+        # _id, '-date'
+        self.assertEqual(len(info), 3)
+
+        # Indexes are lazy so use list() to perform query
+        list(BlogPost.objects)
+        info = BlogPost.objects._collection.index_information()
+        info = [(value['key'],
+                 value.get('unique', False),
+                 value.get('sparse', False))
+                for key, value in info.iteritems()]
+        self.assertTrue(([('addDate', -1)], True, True) in info)
+
+        BlogPost.drop_collection()
+
+
     def test_unique(self):
         """Ensure that uniqueness constraints are applied to fields.
         """

tests/fields.py

@@ -187,6 +187,66 @@ class FieldTest(unittest.TestCase):
         log.time = '1pm'
         self.assertRaises(ValidationError, log.validate)
 
+    def test_datetime(self):
+        """Tests showing pymongo datetime fields handling of microseconds.
+        Microseconds are rounded to the nearest millisecond and pre UTC
+        handling is wonky.
+
+        See: http://api.mongodb.org/python/current/api/bson/son.html#dt
+        """
+        class LogEntry(Document):
+            date = DateTimeField()
+
+        LogEntry.drop_collection()
+
+        # Post UTC - microseconds are rounded (down) nearest millisecond and dropped
+        d1 = datetime.datetime(1970, 01, 01, 00, 00, 01, 999)
+        d2 = datetime.datetime(1970, 01, 01, 00, 00, 01)
+        log = LogEntry()
+        log.date = d1
+        log.save()
+        log.reload()
+        self.assertNotEquals(log.date, d1)
+        self.assertEquals(log.date, d2)
+
+        # Post UTC - microseconds are rounded (down) nearest millisecond
+        d1 = datetime.datetime(1970, 01, 01, 00, 00, 01, 9999)
+        d2 = datetime.datetime(1970, 01, 01, 00, 00, 01, 9000)
+        log.date = d1
+        log.save()
+        log.reload()
+        self.assertNotEquals(log.date, d1)
+        self.assertEquals(log.date, d2)
+
+        # Pre UTC dates microseconds below 1000 are dropped
+        d1 = datetime.datetime(1969, 12, 31, 23, 59, 59, 999)
+        d2 = datetime.datetime(1969, 12, 31, 23, 59, 59)
+        log.date = d1
+        log.save()
+        log.reload()
+        self.assertNotEquals(log.date, d1)
+        self.assertEquals(log.date, d2)
+
+        # Pre UTC microseconds above 1000 is wonky.
+        # log.date has an invalid microsecond value so I can't construct
+        # a date to compare.
+        #
+        # However, the timedelta is predicable with pre UTC timestamps
+        # It always adds 16 seconds and [777216-776217] microseconds
+        for i in xrange(1001, 3113, 33):
+            d1 = datetime.datetime(1969, 12, 31, 23, 59, 59, i)
+            log.date = d1
+            log.save()
+            log.reload()
+            self.assertNotEquals(log.date, d1)
+
+            delta = log.date - d1
+            self.assertEquals(delta.seconds, 16)
+            microseconds = 777216 - (i % 1000)
+            self.assertEquals(delta.microseconds, microseconds)
+
+        LogEntry.drop_collection()
+
     def test_list_validation(self):
         """Ensure that a list field only accepts lists with valid elements.
         """

tests/queryset.py

@@ -9,6 +9,7 @@ from mongoengine.queryset import (QuerySet, QuerySetManager,
                                   MultipleObjectsReturned, DoesNotExist,
                                   QueryFieldList)
 from mongoengine import *
+from mongoengine.tests import query_counter
 
 
 class QuerySetTest(unittest.TestCase):
@@ -331,6 +332,125 @@ class QuerySetTest(unittest.TestCase):
         person = self.Person.objects.get(age=50)
         self.assertEqual(person.name, "User C")
 
+    def test_bulk_insert(self):
+        """Ensure that query by array position works.
+        """
+
+        class Comment(EmbeddedDocument):
+            name = StringField()
+
+        class Post(EmbeddedDocument):
+            comments = ListField(EmbeddedDocumentField(Comment))
+
+        class Blog(Document):
+            title = StringField()
+            tags = ListField(StringField())
+            posts = ListField(EmbeddedDocumentField(Post))
+
+        Blog.drop_collection()
+
+        with query_counter() as q:
+            self.assertEqual(q, 0)
+
+            comment1 = Comment(name='testa')
+            comment2 = Comment(name='testb')
+            post1 = Post(comments=[comment1, comment2])
+            post2 = Post(comments=[comment2, comment2])
+
+            blogs = []
+            for i in xrange(1, 100):
+                blogs.append(Blog(title="post %s" % i, posts=[post1, post2]))
+
+            Blog.objects.insert(blogs, load_bulk=False)
+            self.assertEqual(q, 2) # 1 for the inital connection and 1 for the insert
+
+            Blog.objects.insert(blogs)
+            self.assertEqual(q, 4) # 1 for insert, and 1 for in bulk
+
+        Blog.drop_collection()
+
+        comment1 = Comment(name='testa')
+        comment2 = Comment(name='testb')
+        post1 = Post(comments=[comment1, comment2])
+        post2 = Post(comments=[comment2, comment2])
+        blog1 = Blog(title="code", posts=[post1, post2])
+        blog2 = Blog(title="mongodb", posts=[post2, post1])
+        blog1, blog2 = Blog.objects.insert([blog1, blog2])
+        self.assertEqual(blog1.title, "code")
+        self.assertEqual(blog2.title, "mongodb")
+
+        self.assertEqual(Blog.objects.count(), 2)
+
+        # test handles people trying to upsert
+        def throw_operation_error():
+            blogs = Blog.objects
+            Blog.objects.insert(blogs)
+
+        self.assertRaises(OperationError, throw_operation_error)
+
+        # test handles other classes being inserted
+        def throw_operation_error_wrong_doc():
+            class Author(Document):
+                pass
+            Blog.objects.insert(Author())
+
+        self.assertRaises(OperationError, throw_operation_error_wrong_doc)
+
+        def throw_operation_error_not_a_document():
+            Blog.objects.insert("HELLO WORLD")
+
+        self.assertRaises(OperationError, throw_operation_error_not_a_document)
+
+        Blog.drop_collection()
+
+        blog1 = Blog(title="code", posts=[post1, post2])
+        blog1 = Blog.objects.insert(blog1)
+        self.assertEqual(blog1.title, "code")
+        self.assertEqual(Blog.objects.count(), 1)
+
+        Blog.drop_collection()
+        blog1 = Blog(title="code", posts=[post1, post2])
+        obj_id = Blog.objects.insert(blog1, load_bulk=False)
+        self.assertEquals(obj_id.__class__.__name__, 'ObjectId')
+
+    def test_slave_okay(self):
+        """Ensures that a query can take slave_okay syntax
+        """
+        person1 = self.Person(name="User A", age=20)
+        person1.save()
+        person2 = self.Person(name="User B", age=30)
+        person2.save()
+
+        # Retrieve the first person from the database
+        person = self.Person.objects.slave_okay(True).first()
+        self.assertTrue(isinstance(person, self.Person))
+        self.assertEqual(person.name, "User A")
+        self.assertEqual(person.age, 20)
+
+    def test_cursor_args(self):
+        """Ensures the cursor args can be set as expected
+        """
+        p = self.Person.objects
+        # Check default
+        self.assertEqual(p._cursor_args,
+                {'snapshot': False, 'slave_okay': False, 'timeout': True})
+
+        p.snapshot(False).slave_okay(False).timeout(False)
+        self.assertEqual(p._cursor_args,
+                {'snapshot': False, 'slave_okay': False, 'timeout': False})
+
+        p.snapshot(True).slave_okay(False).timeout(False)
+        self.assertEqual(p._cursor_args,
+                {'snapshot': True, 'slave_okay': False, 'timeout': False})
+
+        p.snapshot(True).slave_okay(True).timeout(False)
+        self.assertEqual(p._cursor_args,
+                {'snapshot': True, 'slave_okay': True, 'timeout': False})
+
+        p.snapshot(True).slave_okay(True).timeout(True)
+        self.assertEqual(p._cursor_args,
+                {'snapshot': True, 'slave_okay': True, 'timeout': True})
+
     def test_repeated_iteration(self):
         """Ensure that QuerySet rewinds itself one iteration finishes.
         """
@@ -2099,8 +2219,27 @@ class QuerySetTest(unittest.TestCase):
         Number.drop_collection()
 
 
+    def test_ensure_index(self):
+        """Ensure that manual creation of indexes works.
+        """
+        class Comment(Document):
+            message = StringField()
+
+        Comment.objects.ensure_index('message')
+
+        info = Comment.objects._collection.index_information()
+        info = [(value['key'],
+                 value.get('unique', False),
+                 value.get('sparse', False))
+                for key, value in info.iteritems()]
+        self.assertTrue(([('_types', 1), ('message', 1)], False, False) in info)
+
+
 class QTest(unittest.TestCase):
 
+    def setUp(self):
+        connect(db='mongoenginetest')
+
     def test_empty_q(self):
         """Ensure that empty Q objects won't hurt.
         """

tests/signals.py

@@ -0,0 +1,130 @@
+# -*- coding: utf-8 -*-
+import unittest
+
+from mongoengine import *
+from mongoengine import signals
+
+signal_output = []
+
+
+class SignalTests(unittest.TestCase):
+    """
+    Testing signals before/after saving and deleting.
+    """
+
+    def get_signal_output(self, fn, *args, **kwargs):
+        # Flush any existing signal output
+        global signal_output
+        signal_output = []
+        fn(*args, **kwargs)
+        return signal_output
+
+    def setUp(self):
+        connect(db='mongoenginetest')
+        class Author(Document):
+            name = StringField()
+
+            def __unicode__(self):
+                return self.name
+
+            @classmethod
+            def pre_init(cls, instance, **kwargs):
+                signal_output.append('pre_init signal, %s' % cls.__name__)
+                signal_output.append(str(kwargs['values']))
+
+            @classmethod
+            def post_init(cls, instance, **kwargs):
+                signal_output.append('post_init signal, %s' % instance)
+
+            @classmethod
+            def pre_save(cls, instance, **kwargs):
+                signal_output.append('pre_save signal, %s' % instance)
+
+            @classmethod
+            def post_save(cls, instance, **kwargs):
+                signal_output.append('post_save signal, %s' % instance)
+                if 'created' in kwargs:
+                    if kwargs['created']:
+                        signal_output.append('Is created')
+                    else:
+                        signal_output.append('Is updated')
+
+            @classmethod
+            def pre_delete(cls, instance, **kwargs):
+                signal_output.append('pre_delete signal, %s' % instance)
+
+            @classmethod
+            def post_delete(cls, instance, **kwargs):
+                signal_output.append('post_delete signal, %s' % instance)
+
+        self.Author = Author
+
+        # Save up the number of connected signals so that we can check at the end
+        # that all the signals we register get properly unregistered
+        self.pre_signals = (
+            len(signals.pre_init.receivers),
+            len(signals.post_init.receivers),
+            len(signals.pre_save.receivers),
+            len(signals.post_save.receivers),
+            len(signals.pre_delete.receivers),
+            len(signals.post_delete.receivers)
+        )
+
+        signals.pre_init.connect(Author.pre_init)
+        signals.post_init.connect(Author.post_init)
+        signals.pre_save.connect(Author.pre_save)
+        signals.post_save.connect(Author.post_save)
+        signals.pre_delete.connect(Author.pre_delete)
+        signals.post_delete.connect(Author.post_delete)
+
+    def tearDown(self):
+        signals.pre_init.disconnect(self.Author.pre_init)
+        signals.post_init.disconnect(self.Author.post_init)
+        signals.post_delete.disconnect(self.Author.post_delete)
+        signals.pre_delete.disconnect(self.Author.pre_delete)
+        signals.post_save.disconnect(self.Author.post_save)
+        signals.pre_save.disconnect(self.Author.pre_save)
+
+        # Check that all our signals got disconnected properly.
+        post_signals = (
+            len(signals.pre_init.receivers),
+            len(signals.post_init.receivers),
+            len(signals.pre_save.receivers),
+            len(signals.post_save.receivers),
+            len(signals.pre_delete.receivers),
+            len(signals.post_delete.receivers)
+        )
+
+        self.assertEqual(self.pre_signals, post_signals)
+
+    def test_model_signals(self):
+        """ Model saves should throw some signals. """
+
+        def create_author():
+            a1 = self.Author(name='Bill Shakespeare')
+
+        self.assertEqual(self.get_signal_output(create_author), [
+            "pre_init signal, Author",
+            "{'name': 'Bill Shakespeare'}",
+            "post_init signal, Bill Shakespeare",
+        ])
+
+        a1 = self.Author(name='Bill Shakespeare')
+        self.assertEqual(self.get_signal_output(a1.save), [
+            "pre_save signal, Bill Shakespeare",
+            "post_save signal, Bill Shakespeare",
+            "Is created"
+        ])
+
+        a1.reload()
+        a1.name='William Shakespeare'
+        self.assertEqual(self.get_signal_output(a1.save), [
+            "pre_save signal, William Shakespeare",
+            "post_save signal, William Shakespeare",
+            "Is updated"
+        ])
+
+        self.assertEqual(self.get_signal_output(a1.delete), [
+            'pre_delete signal, William Shakespeare',
+            'post_delete signal, William Shakespeare',
+        ])