Add CellMappingList object

The ability to get a list of all CellMapping objects is needed for some
tooling around adding new hosts to a cell. This adds the necessary
class/method.

Change-Id: Ia402a49d68a5c69891d39c95ac92ea1ceeb99739

nova/objects/cell_mapping.py

@@ -103,3 +103,23 @@ class CellMapping(base.NovaTimestampObject, base.NovaObject):
     @base.remotable
     def destroy(self):
         self._destroy_in_db(self._context, self.uuid)
+
+
+@base.NovaObjectRegistry.register
+class CellMappingList(base.ObjectListBase, base.NovaObject):
+    # Version 1.0: Initial version
+    VERSION = '1.0'
+
+    fields = {
+        'objects': fields.ListOfObjectsField('CellMapping'),
+    }
+
+    @staticmethod
+    @db_api.api_context_manager.reader
+    def _get_all_from_db(context):
+        return context.session.query(api_models.CellMapping).all()
+
+    @base.remotable_classmethod
+    def get_all(cls, context):
+        db_mappings = cls._get_all_from_db(context)
+        return base.obj_make_list(context, cls(), CellMapping, db_mappings)

nova/tests/functional/db/test_cell_mapping.py

@@ -19,6 +19,21 @@ from nova import test
 from nova.tests import fixtures
 
 
+SAMPLE_MAPPING = {'uuid': '',
+                  'name': 'fake-cell',
+                  'transport_url': 'rabbit:///',
+                  'database_connection': 'mysql+pymysql:///'}
+
+
+def create_mapping(**kwargs):
+    args = SAMPLE_MAPPING.copy()
+    if 'uuid' not in kwargs:
+        args['uuid'] = uuidutils.generate_uuid()
+    args.update(kwargs)
+    ctxt = context.RequestContext()
+    return cell_mapping.CellMapping._create_in_db(ctxt, args)
+
+
 class CellMappingTestCase(test.NoDBTestCase):
     USES_DB_SELF = True
 
@@ -27,22 +42,9 @@ class CellMappingTestCase(test.NoDBTestCase):
         self.useFixture(fixtures.Database(database='api'))
         self.context = context.RequestContext('fake-user', 'fake-project')
         self.mapping_obj = cell_mapping.CellMapping()
-        self.uuid = uuidutils.generate_uuid()
-
-    sample_mapping = {'uuid': '',
-                'name': 'fake-cell',
-                'transport_url': 'rabbit:///',
-                'database_connection': 'mysql+pymysql:///'}
-
-    def _create_mapping(self, **kwargs):
-        args = self.sample_mapping.copy()
-        if 'uuid' not in kwargs:
-            args['uuid'] = self.uuid
-        args.update(kwargs)
-        return self.mapping_obj._create_in_db(self.context, args)
 
     def test_get_by_uuid(self):
-        mapping = self._create_mapping()
+        mapping = create_mapping()
         db_mapping = self.mapping_obj._get_by_uuid_from_db(self.context,
                 mapping['uuid'])
         for key in self.mapping_obj.fields.keys():
@@ -50,10 +52,11 @@ class CellMappingTestCase(test.NoDBTestCase):
 
     def test_get_by_uuid_not_found(self):
         self.assertRaises(exception.CellMappingNotFound,
-                self.mapping_obj._get_by_uuid_from_db, self.context, self.uuid)
+                self.mapping_obj._get_by_uuid_from_db, self.context,
+                          uuidutils.generate_uuid())
 
     def test_save_in_db(self):
-        mapping = self._create_mapping()
+        mapping = create_mapping()
         self.mapping_obj._save_in_db(self.context, mapping['uuid'],
                 {'name': 'meow'})
         db_mapping = self.mapping_obj._get_by_uuid_from_db(self.context,
@@ -64,7 +67,7 @@ class CellMappingTestCase(test.NoDBTestCase):
             self.assertEqual(db_mapping[key], mapping[key])
 
     def test_destroy_in_db(self):
-        mapping = self._create_mapping()
+        mapping = create_mapping()
         self.mapping_obj._get_by_uuid_from_db(self.context, mapping['uuid'])
         self.mapping_obj._destroy_in_db(self.context, mapping['uuid'])
         self.assertRaises(exception.CellMappingNotFound,
@@ -73,4 +76,25 @@ class CellMappingTestCase(test.NoDBTestCase):
 
     def test_destroy_in_db_not_found(self):
         self.assertRaises(exception.CellMappingNotFound,
-                self.mapping_obj._destroy_in_db, self.context, self.uuid)
+                self.mapping_obj._destroy_in_db, self.context,
+                uuidutils.generate_uuid())
+
+
+class CellMappingListTestCase(test.NoDBTestCase):
+    def setUp(self):
+        super(CellMappingListTestCase, self).setUp()
+        self.useFixture(fixtures.Database(database='api'))
+
+    def test_get_all(self):
+        mappings = {}
+        mapping = create_mapping()
+        mappings[mapping['uuid']] = mapping
+        mapping = create_mapping()
+        mappings[mapping['uuid']] = mapping
+
+        ctxt = context.RequestContext()
+        db_mappings = cell_mapping.CellMappingList._get_all_from_db(ctxt)
+        for db_mapping in db_mappings:
+            mapping = mappings[db_mapping.uuid]
+            for key in cell_mapping.CellMapping.fields.keys():
+                self.assertEqual(db_mapping[key], mapping[key])

nova/tests/unit/objects/test_cell_mapping.py

@@ -106,3 +106,25 @@ class TestCellMappingObject(test_objects._LocalTest,
 class TestRemoteCellMappingObject(test_objects._RemoteTest,
                                   _TestCellMappingObject):
     pass
+
+
+class _TestCellMappingListObject(object):
+    @mock.patch.object(cell_mapping.CellMappingList, '_get_all_from_db')
+    def test_get_all(self, get_all_from_db):
+        db_mapping = get_db_mapping()
+        get_all_from_db.return_value = [db_mapping]
+
+        mapping_obj = objects.CellMappingList.get_all(self.context)
+
+        get_all_from_db.assert_called_once_with(self.context)
+        self.compare_obj(mapping_obj.objects[0], db_mapping)
+
+
+class TestCellMappingListObject(test_objects._LocalTest,
+                                _TestCellMappingListObject):
+    pass
+
+
+class TestRemoteCellMappingListObject(test_objects._RemoteTest,
+                                      _TestCellMappingListObject):
+    pass

nova/tests/unit/objects/test_objects.py

@@ -1108,6 +1108,7 @@ object_data = {
     'BlockDeviceMappingList': '1.17-1e568eecb91d06d4112db9fd656de235',
     'BuildRequest': '1.0-c6cd434db5cbdb4d1ebb935424261377',
     'CellMapping': '1.0-7f1a7e85a22bbb7559fc730ab658b9bd',
+    'CellMappingList': '1.0-4ee0d9efdfd681fed822da88376e04d2',
     'ComputeNode': '1.16-2436e5b836fa0306a3c4e6d9e5ddacec',
     'ComputeNodeList': '1.14-3b6f4f5ade621c40e70cb116db237844',
     'DNSDomain': '1.0-7b0b2dab778454b6a7b6c66afe163a1a',