db: Add resources column in instance_extra table

This change adds a resources deferred-load column to instance_extra,
which will stores a list of resources for a given instance in the
form of a JSON blob.

Change-Id: I26d1fa8d0dc2fdf066f3a7017a74cda679d3efa1
Partially-Implements: blueprint virtual-persistent-memory
Co-Authored-By: He Jie Xu <hejie.xu@intel.com>

nova/db/sqlalchemy/api.py

@@ -1777,7 +1777,7 @@ def instance_create(context, values):
          'pci_requests': None,
          'vcpu_model': None,
          'trusted_certs': None,
-         'vpmems': None,
+         'resources': None,
          })
     instance_ref['extra'].update(values.pop('extra', {}))
     instance_ref.update(values)
@@ -3066,7 +3066,7 @@ def instance_extra_get_by_instance_uuid(context, instance_uuid,
         filter_by(instance_uuid=instance_uuid)
     if columns is None:
         columns = ['numa_topology', 'pci_requests', 'flavor', 'vcpu_model',
-                   'trusted_certs', 'vpmems', 'migration_context']
+                   'trusted_certs', 'resources', 'migration_context']
     for column in columns:
         query = query.options(undefer(column))
     instance_extra = query.first()

nova/db/sqlalchemy/migrate_repo/versions/402_add_resources.py

@@ -0,0 +1,31 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from sqlalchemy import Column
+from sqlalchemy import MetaData
+from sqlalchemy import Table
+from sqlalchemy import Text
+
+
+BASE_TABLE_NAME = 'instance_extra'
+NEW_COLUMN_NAME = 'resources'
+
+
+def upgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+
+    for prefix in ('', 'shadow_'):
+        table = Table(prefix + BASE_TABLE_NAME, meta, autoload=True)
+        new_column = Column(NEW_COLUMN_NAME, Text, nullable=True)
+        if not hasattr(table.c, NEW_COLUMN_NAME):
+            table.create_column(new_column)

nova/db/sqlalchemy/models.py

@@ -391,7 +391,9 @@ class InstanceExtra(BASE, NovaBase, models.SoftDeleteMixin):
     migration_context = orm.deferred(Column(Text))
     keypairs = orm.deferred(Column(Text))
     trusted_certs = orm.deferred(Column(Text))
-    vpmems = orm.deferred(Column(Text))
+    # NOTE(Luyao): 'vpmems' is still in the database
+    # and can be removed in the future release.
+    resources = orm.deferred(Column(Text))
     instance = orm.relationship(Instance,
                             backref=orm.backref('extra',
                                                 uselist=False),

nova/tests/unit/db/test_db_api.py

@@ -3372,7 +3372,7 @@ class InstanceExtraTestCase(test.TestCase):
         db.instance_extra_update_by_uuid(self.ctxt, self.instance['uuid'],
                                          {'numa_topology': 'changed',
                                           'trusted_certs': "['123', 'foo']",
-                                          'vpmems': "['vpmem0', 'vpmem1']",
+                                          'resources': "['res0', 'res1']",
                                           })
         inst_extra = db.instance_extra_get_by_instance_uuid(
             self.ctxt, self.instance['uuid'])
@@ -3380,7 +3380,7 @@ class InstanceExtraTestCase(test.TestCase):
         # NOTE(jackie-truong): trusted_certs is stored as a Text type in
         # instance_extra and read as a list of strings
         self.assertEqual("['123', 'foo']", inst_extra.trusted_certs)
-        self.assertEqual("['vpmem0', 'vpmem1']", inst_extra.vpmems)
+        self.assertEqual("['res0', 'res1']", inst_extra.resources)
 
     def test_instance_extra_update_by_uuid_and_create(self):
         @sqlalchemy_api.pick_context_manager_writer
@@ -3405,13 +3405,14 @@ class InstanceExtraTestCase(test.TestCase):
     def test_instance_extra_get_with_columns(self):
         extra = db.instance_extra_get_by_instance_uuid(
             self.ctxt, self.instance['uuid'],
-            columns=['numa_topology', 'vcpu_model', 'trusted_certs', 'vpmems'])
+            columns=['numa_topology', 'vcpu_model', 'trusted_certs',
+                     'resources'])
         self.assertRaises(SQLAlchemyError,
                           extra.__getitem__, 'pci_requests')
         self.assertIn('numa_topology', extra)
         self.assertIn('vcpu_model', extra)
         self.assertIn('trusted_certs', extra)
-        self.assertIn('vpmems', extra)
+        self.assertIn('resources', extra)
 
 
 class ServiceTestCase(test.TestCase, ModelsObjectComparatorMixin):

nova/tests/unit/db/test_migrations.py

@@ -788,7 +788,10 @@ class NovaMigrationsCheckers(test_migrations.ModelsMigrationsSync,
         def removed_column(element):
             # Define a whitelist of columns that would be removed from the
             # DB at a later release.
-            column_whitelist = {'instances': ['internal_id']}
+            # NOTE(Luyao) The vpmems column was added to the schema in train,
+            # and removed from the model in train.
+            column_whitelist = {'instances': ['internal_id'],
+                                'instance_extra': ['vpmems']}
 
             if element[0] != 'remove_column':
                 return False
@@ -1048,6 +1051,10 @@ class NovaMigrationsCheckers(test_migrations.ModelsMigrationsSync,
             self.assertColumnExists(
                 engine, '%smigrations' % prefix, 'project_id')
 
+    def _check_402(self, engine, data):
+        self.assertColumnExists(engine, 'instance_extra', 'resources')
+        self.assertColumnExists(engine, 'shadow_instance_extra', 'resources')
+
 
 class TestNovaMigrationsSQLite(NovaMigrationsCheckers,
                                test_fixtures.OpportunisticDBTestMixin,