db: Move main DB migrations

We place these in a 'legacy_migrations' directory, as we will soon be
adding alembic-based migrations in a 'migration' directory.

Change-Id: Ib927e4c48f59a467a913875111ffbf64ffe0de90
Signed-off-by: Stephen Finucane <stephenfin@redhat.com>

doc/source/user/upgrade.rst

@@ -176,7 +176,7 @@ Schema Migrations
 ''''''''''''''''''
 
 Schema migrations are defined in
-``nova/db/sqlalchemy/migrate_repo/versions`` and in
+``nova/db/main/legacy_migrations/versions`` and in
 ``nova/db/sqlalchemy/api_migrations/migrate_repo/versions``. They are
 the routines that transform our database structure, which should be
 additive and able to be applied to a running system before service

nova/db/migration.py

@@ -45,7 +45,7 @@ def get_engine(database='main', context=None):
 def find_migrate_repo(database='main'):
     """Get the path for the migrate repository."""
     global _REPOSITORY
-    rel_path = os.path.join('sqlalchemy', 'migrate_repo')
+    rel_path = os.path.join('main', 'legacy_migrations')
     if database == 'api':
         rel_path = os.path.join('sqlalchemy', 'api_migrations', 'migrate_repo')
     path = os.path.join(os.path.abspath(os.path.dirname(__file__)), rel_path)

nova/tests/unit/db/test_migrations.py

@@ -46,8 +46,8 @@ import sqlalchemy
 import sqlalchemy.exc
 import testtools
 
+from nova.db.main import legacy_migrations
 from nova.db import migration
-from nova.db.sqlalchemy import migrate_repo
 from nova.db.sqlalchemy import models
 from nova import test
 from nova.tests import fixtures as nova_fixtures
@@ -73,7 +73,7 @@ class NovaMigrationsCheckers(test_migrations.ModelsMigrationsSync,
     @property
     def REPOSITORY(self):
         return repository.Repository(
-            os.path.abspath(os.path.dirname(migrate_repo.__file__)))
+            os.path.abspath(os.path.dirname(legacy_migrations.__file__)))
 
     @property
     def migration_api(self):
@@ -272,9 +272,14 @@ class ProjectTestCase(test.NoDBTestCase):
         topdir = os.path.normpath(os.path.dirname(__file__) + '/../../../')
         # Walk both the nova_api and nova (cell) database migrations.
         includes_downgrade = []
-        for subdir in ('api_migrations', ''):
-            py_glob = os.path.join(topdir, "db", "sqlalchemy", subdir,
-                                   "migrate_repo", "versions", "*.py")
+        for directory in (
+            os.path.join(topdir, 'db', 'main', 'legacy_migrations'),
+            os.path.join(
+                topdir, 'db', 'sqlalchemy', 'api_migrations',
+                'migrate_repo',
+            ),
+        ):
+            py_glob = os.path.join(directory, 'versions', '*.py')
             for path in glob.iglob(py_glob):
                 has_upgrade = False
                 has_downgrade = False

tools/db/schema_diff.py

@@ -126,7 +126,7 @@ def _get_db_driver_class(db_url):
 # Migrate
 
 
-MIGRATE_REPO = os.path.join(os.getcwd(), "nova/db/sqlalchemy/migrate_repo")
+MIGRATE_REPO = os.path.join(os.getcwd(), "nova/db/main/legacy_migrations")
 
 
 def _migrate(db_url, migration_version):

tools/reserve-migrations.py

@@ -5,7 +5,7 @@ import glob
 import os
 import subprocess
 
-BASE = 'nova/db/sqlalchemy/migrate_repo/versions'.split('/')
+BASE = 'nova/db/main/legacy_migrations/versions'.split('/')
 API_BASE = 'nova/db/sqlalchemy/api_migrations/migrate_repo/versions'.split('/')
 
 STUB = \