From 2fc4b6ccafb1770e6f6c0c4d0c86b456529e5603 Mon Sep 17 00:00:00 2001
From: Surya <suryaseetharaman.9@gmail.com>
Date: Tue, 14 Aug 2018 13:24:34 +0200
Subject: [PATCH] Add get_by_cell_and_project() method to InstanceMappingList

Adds a new query method to query for instance_mappings in the provided
cell for the provided project_id.

Related to blueprint handling-down-cell

Change-Id: I4b4466de9160267c23b88c2b35673745fd989f4d
---
 nova/objects/instance_mapping.py              | 16 ++++++++
 .../functional/db/test_instance_mapping.py    | 37 +++++++++++++++++++
 2 files changed, 53 insertions(+)

diff --git a/nova/objects/instance_mapping.py b/nova/objects/instance_mapping.py
index ef389735799b..162b4da49f1f 100644
--- a/nova/objects/instance_mapping.py
+++ b/nova/objects/instance_mapping.py
@@ -249,3 +249,19 @@ class InstanceMappingList(base.ObjectListBase, base.NovaObject):
     @classmethod
     def destroy_bulk(cls, context, instance_uuids):
         return cls._destroy_bulk_in_db(context, instance_uuids)
+
+    @staticmethod
+    @db_api.api_context_manager.reader
+    def _get_by_cell_and_project_from_db(context, cell_id, project_id):
+        return (context.session.query(api_models.InstanceMapping)
+                .options(joinedload('cell_mapping'))
+                .filter_by(cell_id=cell_id)
+                .filter_by(project_id=project_id)
+                .all())
+
+    @classmethod
+    def get_by_cell_and_project(cls, context, cell_id, project_id):
+        db_mappings = cls._get_by_cell_and_project_from_db(context, cell_id,
+                                                           project_id)
+        return base.obj_make_list(context, cls(), objects.InstanceMapping,
+                db_mappings)
diff --git a/nova/tests/functional/db/test_instance_mapping.py b/nova/tests/functional/db/test_instance_mapping.py
index 9e0ed3821c1b..2a5dd2cab875 100644
--- a/nova/tests/functional/db/test_instance_mapping.py
+++ b/nova/tests/functional/db/test_instance_mapping.py
@@ -255,3 +255,40 @@ class InstanceMappingListTestCase(test.NoDBTestCase):
             self.context, uuids + [uuidsentinel.deleted_instance])
         self.assertEqual(sorted(uuids),
                          sorted([m.instance_uuid for m in mappings]))
+
+    def test_get_by_cell_and_project(self):
+        cells = []
+        # Create two cells
+        for uuid in (uuidsentinel.cell1, uuidsentinel.cell2):
+            cm = cell_mapping.CellMapping(context=self.context, uuid=uuid,
+                                          database_connection="fake:///",
+                                          transport_url='fake://')
+            cm.create()
+            cells.append(cm)
+        # With each cell having two instance_mappings of two project_ids.
+        uuids = {cells[0].id: [uuidsentinel.c1i1, uuidsentinel.c1i2],
+                 cells[1].id: [uuidsentinel.c2i1, uuidsentinel.c2i2]}
+        project_ids = ['fake-project-1', 'fake-project-2']
+        for cell_id, uuid in uuids.items():
+            instance_mapping.InstanceMapping._create_in_db(
+                    self.context,
+                    {'project_id': project_ids[0],
+                     'cell_id': cell_id,
+                     'instance_uuid': uuid[0]})
+            instance_mapping.InstanceMapping._create_in_db(
+                    self.context,
+                    {'project_id': project_ids[1],
+                     'cell_id': cell_id,
+                     'instance_uuid': uuid[1]})
+
+        ims = instance_mapping.InstanceMappingList.get_by_cell_and_project(
+            self.context, cells[0].id, 'fake-project-2')
+        self.assertEqual([uuidsentinel.c1i2],
+                         sorted([m.instance_uuid for m in ims]))
+        ims = instance_mapping.InstanceMappingList.get_by_cell_and_project(
+            self.context, cells[1].id, 'fake-project-1')
+        self.assertEqual([uuidsentinel.c2i1],
+                         sorted([m.instance_uuid for m in ims]))
+        ims = instance_mapping.InstanceMappingList.get_by_cell_and_project(
+            self.context, cells[0].id, 'fake-project-3')
+        self.assertEqual([], sorted([m.instance_uuid for m in ims]))