From ae347b81caa478602a4656847a1899e05f4fda1f Mon Sep 17 00:00:00 2001
From: Angus Salkeld <asalkeld@redhat.com>
Date: Fri, 20 Dec 2013 12:32:58 +1100
Subject: [PATCH] Add migration test framework

This is partly taken from nova and uses the oslo-incubator test migration
framework.

Change-Id: Ia09e3dd2e85917607025a8cf82aa259445c2c24f
---
 heat/tests/db/__init__.py          |   0
 heat/tests/db/test_migrations.conf |  10 +++
 heat/tests/db/test_migrations.py   | 112 +++++++++++++++++++++++++++++
 3 files changed, 122 insertions(+)
 create mode 100644 heat/tests/db/__init__.py
 create mode 100644 heat/tests/db/test_migrations.conf
 create mode 100644 heat/tests/db/test_migrations.py

diff --git a/heat/tests/db/__init__.py b/heat/tests/db/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/heat/tests/db/test_migrations.conf b/heat/tests/db/test_migrations.conf
new file mode 100644
index 0000000000..f771194c03
--- /dev/null
+++ b/heat/tests/db/test_migrations.conf
@@ -0,0 +1,10 @@
+[DEFAULT]
+# Set up any number of databases to test concurrently.
+# The "name" used in the test is the config variable key.
+
+# A few tests rely on one sqlite database with 'sqlite' as the key.
+
+sqlite=sqlite://
+#sqlitefile=sqlite:///test_migrations_utils.db
+#mysql=mysql+mysqldb://user:pass@localhost/test_migrations_utils
+#postgresql=postgresql+psycopg2://user:pass@localhost/test_migrations_utils
diff --git a/heat/tests/db/test_migrations.py b/heat/tests/db/test_migrations.py
new file mode 100644
index 0000000000..6993437412
--- /dev/null
+++ b/heat/tests/db/test_migrations.py
@@ -0,0 +1,112 @@
+#
+#    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.
+
+"""
+Tests for database migrations. This test case reads the configuration
+file test_migrations.conf for database connection settings
+to use in the tests. For each connection found in the config file,
+the test case runs a series of test cases to ensure that migrations work
+properly both upgrading and downgrading, and that no data loss occurs
+if possible.
+"""
+
+import os
+import shutil
+import sqlalchemy
+import tempfile
+
+from migrate.versioning import repository
+
+from heat.db.sqlalchemy import migrate_repo
+from heat.openstack.common import log as logging
+from heat.openstack.common.db.sqlalchemy import test_migrations
+
+
+LOG = logging.getLogger(__name__)
+
+
+def get_table(engine, name):
+    """Returns an sqlalchemy table dynamically from db.
+
+    Needed because the models don't work for us in migrations
+    as models will be far out of sync with the current data.
+    """
+    metadata = sqlalchemy.MetaData()
+    metadata.bind = engine
+    return sqlalchemy.Table(name, metadata, autoload=True)
+
+
+class TestHeatMigrations(test_migrations.BaseMigrationTestCase,
+                         test_migrations.WalkVersionsMixin):
+    """Test sqlalchemy-migrate migrations."""
+
+    def __init__(self, *args, **kwargs):
+        super(TestHeatMigrations, self).__init__(*args, **kwargs)
+
+        self.DEFAULT_CONFIG_FILE = os.path.join(os.path.dirname(__file__),
+                                                'test_migrations.conf')
+        # Test machines can set the TEST_MIGRATIONS_CONF variable
+        # to override the location of the config file for migration testing
+        self.CONFIG_FILE_PATH = os.environ.get('TEST_MIGRATIONS_CONF',
+                                               self.DEFAULT_CONFIG_FILE)
+        self.MIGRATE_FILE = migrate_repo.__file__
+        self.REPOSITORY = repository.Repository(
+            os.path.abspath(os.path.dirname(self.MIGRATE_FILE)))
+
+    def setUp(self):
+        lock_dir = tempfile.mkdtemp()
+        os.environ["HEAT_LOCK_PATH"] = lock_dir
+
+        super(TestHeatMigrations, self).setUp()
+
+        def clean_lock_dir():
+            shutil.rmtree(lock_dir, ignore_errors=True)
+
+        self.addCleanup(clean_lock_dir)
+        self.snake_walk = False
+        self.downgrade = False
+        if self.migration_api is None:
+            temp = __import__('heat.db.sqlalchemy.migration',
+                              globals(), locals(),
+                              ['versioning_api'], -1)
+            self.migration_api = temp.versioning_api
+            self.INIT_VERSION = temp.INIT_VERSION
+
+    def test_walk_versions(self):
+        for key, engine in self.engines.items():
+            self._walk_versions(engine, self.snake_walk, self.downgrade)
+
+    def assertColumnExists(self, engine, table, column):
+        t = get_table(engine, table)
+        self.assertIn(column, t.c)
+
+    def assertColumnNotExists(self, engine, table, column):
+        t = get_table(engine, table)
+        self.assertNotIn(column, t.c)
+
+    def assertIndexExists(self, engine, table, index):
+        t = get_table(engine, table)
+        index_names = [idx.name for idx in t.indexes]
+        self.assertIn(index, index_names)
+
+    def assertIndexMembers(self, engine, table, index, members):
+        self.assertIndexExists(engine, table, index)
+
+        t = get_table(engine, table)
+        index_columns = None
+        for idx in t.indexes:
+            if idx.name == index:
+                index_columns = idx.columns.keys()
+                break
+
+        self.assertEqual(sorted(members), sorted(index_columns))