Added: ./keystone-manage database goto <version>

- Jumps to a given version without performing migrations
- Analog of `UPDATE migrate_version SET version=<version>;`

Change-Id: I682d3c2d83b22bcd30e672a11a35c8804dd5a1ea

doc/source/migration.rst

@@ -44,17 +44,18 @@ support::
 
     $ ./bin/keystone-manage database version_control
 
-This command simply creates a ``migrate_version`` table, set at version 0,
-which indicates that no migrations have been applied.
+This command simply creates a ``migrate_version`` table, set at
+``version_number`` 0, which indicates that no migrations have been applied.
 
-If you are starting with an existing schema, you can set your database to
-the current schema version using a SQL command. For example, if you're
-starting from a diablo-compatible database, set your current
-database version to ``1``::
+If you are starting with an existing schema, you can jump to a specific
+schema version without performing migrations using the ``database goto``
+command. For example, if you're starting from a diablo-compatible
+database, set your current database ``version_number`` to ``1`` using::
 
-    UPDATE migrate_version SET version=1;
+    $ ./bin/keystone-manage database goto <version_number>
 
-Determine your appropriate database ``version`` by referencing the following table:
+Determine your appropriate database ``version_number`` by referencing the
+following table:
 
     +------------+-------------+
     | Release    | ``version`` |
@@ -94,6 +95,10 @@ Check your current schema version::
 
     $ ./bin/keystone-manage database version
 
+Jump to a specific version without performing migrations::
+
+    $ ./bin/keystone-manage database goto <version_number>
+
 Upgrade to a specific version::
 
     $ ./bin/keystone-manage database upgrade <version_number>

keystone/backends/sqlalchemy/migration.py

@@ -32,6 +32,14 @@ from keystone.logic.types import fault
 logger = logging.getLogger(__name__)
 
 
+def get_migrate_repo_path():
+    """Get the path for the migrate repository."""
+    path = os.path.join(os.path.abspath(os.path.dirname(__file__)),
+                        'migrate_repo')
+    assert os.path.exists(path)
+    return path
+
+
 def get_migrate_repo(repo_path):
     return versioning_api.repository.Repository(repo_path)
 
@@ -48,6 +56,35 @@ def get_db_version(engine, repo_path):
     return get_schema(engine, repo_path).version
 
 
+def db_goto_version(options, version):
+    """
+    Jump to a specific database version without performing migrations.
+
+    :param options: options dict
+    :param version: version to jump to
+    """
+
+    @versioning_api.with_engine
+    def set_db_version(url, repository, old_v, new_v, **opts):
+        engine = opts.pop('engine')
+        schema = get_schema(engine, repo_path)
+        schema.update_repository_table(old_v, new_v)
+        return True
+
+    repo_path = get_migrate_repo_path()
+    sql_connection = options['sql_connection']
+    new_version = int(version)
+    try:
+        old_version = versioning_api.db_version(sql_connection, repo_path)
+        if new_version != old_version:
+            return set_db_version(sql_connection, repo_path, old_version,
+                new_version)
+    except versioning_exceptions.DatabaseNotControlledError:
+        msg = (_("database '%(sql_connection)s' is not under "
+                 "migration control") % locals())
+        raise fault.DatabaseMigrationError(msg)
+
+
 def db_version(options):
     """
     Return the database's current migration number
@@ -137,11 +174,3 @@ def db_sync(options, version=None):
         pass
 
     upgrade(options, version=version)
-
-
-def get_migrate_repo_path():
-    """Get the path for the migrate repository."""
-    path = os.path.join(os.path.abspath(os.path.dirname(__file__)),
-                        'migrate_repo')
-    assert os.path.exists(path)
-    return path

keystone/manage/__init__.py

@@ -40,9 +40,9 @@ logger = logging.getLogger(__name__)
 # CLI feature set
 OBJECTS = ['user', 'tenant', 'role', 'service',
     'endpointTemplates', 'token', 'endpoint', 'credentials', 'database']
-ACTIONS = ['add', 'list', 'disable', 'delete', 'grant',
-    'revoke',
-    'sync', 'downgrade', 'upgrade', 'version_control', 'version']
+ACTIONS = ['add', 'list', 'disable', 'delete', 'grant', 'revoke',
+    'sync', 'downgrade', 'upgrade', 'version_control', 'version',
+    'goto']
 
 
 # Messages
@@ -342,6 +342,18 @@ def process(*args):
                 raise optparse.OptParseError(
                     'SQL alchemy backend not specified in config')
 
+    elif (object_type, action) == ('database', 'goto'):
+        require_args(args, 1, 'Jumping database versions requires a '
+            'version #')
+        backend_names = options.get('backends', None)
+        if backend_names:
+            if 'keystone.backends.sqlalchemy' in backend_names.split(','):
+                do_db_goto_version(options['keystone.backends.sqlalchemy'],
+                    version=args[2])
+            else:
+                raise optparse.OptParseError(
+                    'SQL alchemy backend not specified in config')
+
     else:
         # Command recognized but not handled: should never reach this
         raise NotImplementedError()
@@ -355,6 +367,14 @@ def do_db_version(options):
     print migration.db_version(options)
 
 
+def do_db_goto_version(options, version):
+    """Override the database's current migration level"""
+    if migration.db_goto_version(options, version):
+        msg = ('Jumped to version=%s (without performing intermediate '
+            'migrations)') % version
+        print msg
+
+
 def do_db_upgrade(options, args):
     """Upgrade the database's migration level"""
     try: