db: Stop checking for DB under sqlalchemy-migrate control

This has been in place since Ocata. If any version since then has been
deployed, this will have already been deployed. Time to drop this.

UpgradeImpact

Change-Id: I5412d78c63cf3381782f5c6fc059641489f89053
Implements: blueprint remove-sqlalchemy-migrate
Signed-off-by: Stephen Finucane <sfinucan@redhat.com>

glance/cmd/manage.py

@@ -172,8 +172,6 @@ class DbCommands(object):
         Place an existing database under migration control and upgrade it.
         """
 
-        alembic_migrations.place_database_under_alembic_control()
-
         a_config = alembic_migrations.get_alembic_config()
         alembic_command.upgrade(a_config, version)
         heads = alembic_migrations.get_current_alembic_heads()

glance/db/migration.py

@@ -19,7 +19,6 @@
 
 """Database setup and migration commands."""
 
-import os
 import threading
 
 from oslo_config import cfg
@@ -49,11 +48,3 @@ EXPAND_BRANCH = 'expand'
 CONTRACT_BRANCH = 'contract'
 CURRENT_RELEASE = 'wallaby'
 ALEMBIC_INIT_VERSION = 'liberty'
-LATEST_REVISION = 'wallaby_contract01'
-INIT_VERSION = 0
-
-MIGRATE_REPO_PATH = os.path.join(
-    os.path.abspath(os.path.dirname(__file__)),
-    'sqlalchemy',
-    'migrate_repo',
-)

glance/db/sqlalchemy/alembic_migrations/__init__.py

@@ -14,19 +14,13 @@
 #    under the License.
 
 import os
-import sys
 
-from alembic import command as alembic_command
 from alembic import config as alembic_config
 from alembic import migration as alembic_migration
 from alembic import script as alembic_script
 from sqlalchemy import MetaData, Table
-from oslo_db import exception as db_exception
-from oslo_db.sqlalchemy import migration as sqla_migration
 
-from glance.db import migration as db_migration
 from glance.db.sqlalchemy import api as db_api
-from glance.i18n import _
 
 
 def get_alembic_config(engine=None):
@@ -75,60 +69,6 @@ def get_current_alembic_heads():
         return heads
 
 
-def get_current_legacy_head():
-    try:
-        legacy_head = sqla_migration.db_version(db_api.get_engine(),
-                                                db_migration.MIGRATE_REPO_PATH,
-                                                db_migration.INIT_VERSION)
-    except db_exception.DBMigrationError:
-        legacy_head = None
-    return legacy_head
-
-
-def is_database_under_alembic_control():
-    if get_current_alembic_heads():
-        return True
-    return False
-
-
-def is_database_under_migrate_control():
-    if get_current_legacy_head():
-        return True
-    return False
-
-
-def place_database_under_alembic_control():
-    a_config = get_alembic_config()
-
-    if not is_database_under_migrate_control():
-        return
-
-    if not is_database_under_alembic_control():
-        print(_("Database is currently not under Alembic's migration "
-                "control."))
-        head = get_current_legacy_head()
-        if head == 42:
-            alembic_version = 'liberty'
-        elif head == 43:
-            alembic_version = 'mitaka01'
-        elif head == 44:
-            alembic_version = 'mitaka02'
-        elif head == 45:
-            alembic_version = 'ocata01'
-        elif head in range(1, 42):
-            print("Legacy head: ", head)
-            sys.exit(_("The current database version is not supported any "
-                       "more. Please upgrade to Liberty release first."))
-        else:
-            sys.exit(_("Unable to place database under Alembic's migration "
-                       "control. Unknown database state, can't proceed "
-                       "further."))
-
-        print(_("Placing database under Alembic's migration control at "
-                "revision:"), alembic_version)
-        alembic_command.stamp(a_config, alembic_version)
-
-
 def get_alembic_branch_head(branch):
     """Return head revision name for particular branch"""
     a_config = get_alembic_config()

glance/tests/unit/test_manage.py

@@ -258,11 +258,8 @@ class TestManage(TestManageBase):
         'glance.db.sqlalchemy.alembic_migrations.get_current_alembic_heads')
     @mock.patch(
         'glance.db.sqlalchemy.alembic_migrations.get_alembic_branch_head')
-    @mock.patch('glance.db.sqlalchemy.alembic_migrations.'
-                'place_database_under_alembic_control')
     @mock.patch('alembic.command.upgrade')
     def test_sync_db_is_already_sync(self, mock_upgrade,
-                                     mock_db_under_alembic_control,
                                      mock_get_alembic_branch_head,
                                      mock_get_current_alembic_heads):
         mock_get_current_alembic_heads.return_value = ['pike_contract01']

releasenotes/notes/drop-support-for-sqlalchemy-migrate-4bcbe7b200697586.yaml

@@ -0,0 +1,8 @@
+---
+upgrade:
+  - |
+    The database migration engine used by Glance for database upgrades was
+    changed from *SQLAlchemy Migrate* to *Alembic* in the 14.0.0 (Ocata)
+    release. Support for *SQLAlchemy Migrate* has now been removed. This
+    means in order to upgrade from a pre-Ocata release to Xena or later,
+    you must upgrade to Wallaby or earlier first.