db: Replace use of 'autoload' parameter

Resolve the following RemovedIn20Warning warnings:

  The autoload parameter is deprecated and will be removed in version
  2.0.  Please use the autoload_with parameter, passing an engine or
  connection.

Change-Id: I10e9bbf14706aece2a59ebb5861004c5b852a592
Signed-off-by: Stephen Finucane <sfinucan@redhat.com>

nova/db/main/api.py

@@ -4162,7 +4162,7 @@ def _get_fk_stmts(metadata, conn, table, column, records):
         fk_shadow_tablename = _SHADOW_TABLE_PREFIX + fk_table.name
         try:
             fk_shadow_table = schema.Table(
-                fk_shadow_tablename, metadata, autoload=True)
+                fk_shadow_tablename, metadata, autoload_with=conn)
         except sqla_exc.NoSuchTableError:
             # No corresponding shadow table; skip it.
             continue
@@ -4257,7 +4257,8 @@ def _archive_deleted_rows_for_table(metadata, tablename, max_rows, before,
     rows_archived = 0
     deleted_instance_uuids = []
     try:
-        shadow_table = schema.Table(shadow_tablename, metadata, autoload=True)
+        shadow_table = schema.Table(
+            shadow_tablename, metadata, autoload_with=conn)
     except sqla_exc.NoSuchTableError:
         # No corresponding shadow table; skip it.
         return rows_archived, deleted_instance_uuids, {}

nova/db/main/legacy_migrations/versions/402_train.py

@@ -63,7 +63,7 @@ def _create_shadow_tables(migrate_engine):
         ):
             continue
 
-        table = sa.Table(table_name, meta, autoload=True)
+        table = sa.Table(table_name, meta, autoload_with=migrate_engine)
 
         columns = []
         for column in table.columns:
@@ -169,13 +169,15 @@ def _create_shadow_tables(migrate_engine):
     # 252_add_instance_extra_table; we don't create indexes for shadow tables
     # in general and these should be removed
 
-    table = sa.Table('shadow_instance_extra', meta, autoload=True)
+    table = sa.Table(
+        'shadow_instance_extra', meta, autoload_with=migrate_engine,
+    )
     idx = sa.Index('shadow_instance_extra_idx', table.c.instance_uuid)
     idx.create(migrate_engine)
 
     # 373_migration_uuid; we should't create indexes for shadow tables
 
-    table = sa.Table('shadow_migrations', meta, autoload=True)
+    table = sa.Table('shadow_migrations', meta, autoload_with=migrate_engine)
     idx = sa.Index('shadow_migrations_uuid', table.c.uuid, unique=True)
     idx.create(migrate_engine)
 

nova/tests/fixtures/nova.py

@@ -841,12 +841,6 @@ class WarningsFixture(fixtures.Fixture):
             message=r'The Engine.execute\(\) method is considered legacy',
             category=sqla_exc.SADeprecationWarning)
 
-        warnings.filterwarnings(
-            'ignore',
-            module='nova',
-            message=r'The autoload parameter is deprecated .*',
-            category=sqla_exc.SADeprecationWarning)
-
         warnings.filterwarnings(
             'ignore',
             module='nova',

nova/tests/unit/db/main/test_api.py

@@ -5714,8 +5714,10 @@ class ArchiveTestCase(test.TestCase, ModelsObjectComparatorMixin):
 
             shadow_table_name = f'shadow_{table_name}'
 
-            table = sa.Table(table_name, metadata, autoload=True)
-            shadow_table = sa.Table(shadow_table_name, metadata, autoload=True)
+            table = sa.Table(table_name, metadata, autoload_with=self.engine)
+            shadow_table = sa.Table(
+                shadow_table_name, metadata, autoload_with=self.engine,
+            )
 
             columns = {c.name: c for c in table.columns}
             shadow_columns = {c.name: c for c in shadow_table.columns}