Revert "Optional separate database for placement API"

This reverts commit 1b5f9f8203c90fe447d33c89f238104026052d1e.

On IRC I we decided that we agreed no migrations should be placement
specific, we should just use the API table migrations to generate the
schema for both DBs.

There is also a separate debate around the alias for the aggregates
table, but that is not really a reason to revert, its just things in
here that will need rework.

Change-Id: I275945aee9d9be8e35d6ddc05515df39d559457a

nova/db/sqlalchemy/api.py

@@ -75,7 +75,6 @@ LOG = logging.getLogger(__name__)
 
 main_context_manager = enginefacade.transaction_context()
 api_context_manager = enginefacade.transaction_context()
-placement_context_manager = enginefacade.transaction_context()
 
 
 def _get_db_conf(conf_group, connection=None):
@@ -109,10 +108,6 @@ def _context_manager_from_context(context):
 def configure(conf):
     main_context_manager.configure(**_get_db_conf(conf.database))
     api_context_manager.configure(**_get_db_conf(conf.api_database))
-    if conf.placement_database.connection is None:
-        conf.placement_database = conf.api_database
-    placement_context_manager.configure(
-        **_get_db_conf(conf.placement_database))
 
 
 def create_context_manager(connection=None):
@@ -147,10 +142,6 @@ def get_api_engine():
     return api_context_manager.get_legacy_facade().get_engine()
 
 
-def get_placement_engine():
-    return placement_context_manager.get_legacy_facade().get_engine()
-
-
 _SHADOW_TABLE_PREFIX = 'shadow_'
 _DEFAULT_QUOTA_NAME = 'default'
 PER_PROJECT_QUOTAS = ['fixed_ips', 'floating_ips', 'networks']

nova/db/sqlalchemy/api_models.py

@@ -354,31 +354,6 @@ class ResourceProviderAggregate(API_BASE):
     aggregate_id = Column(Integer, primary_key=True, nullable=False)
 
 
-class PlacementAggregate(API_BASE):
-    """Represents a grouping of resource providers."""
-
-    # NOTE(rpodolyaka): placement API can optionally use the subset of tables
-    # of api DB instead of requiring its own DB. aggregates table is the only
-    # table which schema is a bit different (additional `name` column), but we
-    # can work around that by providing an additional mapping class to a
-    # subset of table columns, so that this model works for both separate and
-    # shared DBs cases.
-    __table__ = API_BASE.metadata.tables['aggregates']
-    __mapper_args__ = {
-        'exclude_properties': ['name']
-    }
-
-    resource_providers = orm.relationship(
-        'ResourceProvider',
-        secondary='resource_provider_aggregates',
-        primaryjoin=('PlacementAggregate.id == '
-                     'ResourceProviderAggregate.aggregate_id'),
-        secondaryjoin=('ResourceProviderAggregate.resource_provider_id == '
-                       'ResourceProvider.id'),
-        backref='aggregates'
-    )
-
-
 class InstanceGroupMember(API_BASE):
     """Represents the members for an instance group."""
     __tablename__ = 'instance_group_member'

nova/db/sqlalchemy/migration.py

@@ -31,7 +31,6 @@ from nova.i18n import _
 INIT_VERSION = {}
 INIT_VERSION['main'] = 215
 INIT_VERSION['api'] = 0
-INIT_VERSION['placement'] = 0
 _REPOSITORY = {}
 
 LOG = logging.getLogger(__name__)
@@ -42,8 +41,6 @@ def get_engine(database='main', context=None):
         return db_session.get_engine(context=context)
     if database == 'api':
         return db_session.get_api_engine()
-    if database == 'placement':
-        return db_session.get_placement_engine()
 
 
 def db_sync(version=None, database='main', context=None):
@@ -174,8 +171,6 @@ def _find_migrate_repo(database='main'):
     rel_path = 'migrate_repo'
     if database == 'api':
         rel_path = os.path.join('api_migrations', 'migrate_repo')
-    if database == 'placement':
-        rel_path = os.path.join('placement_migrations', 'migrate_repo')
     path = os.path.join(os.path.abspath(os.path.dirname(__file__)),
                         rel_path)
     assert os.path.exists(path)

nova/test.py

@@ -213,7 +213,6 @@ class TestCase(testtools.TestCase):
         if self.USES_DB:
             self.useFixture(nova_fixtures.Database())
             self.useFixture(nova_fixtures.Database(database='api'))
-            self.useFixture(nova_fixtures.Database(database='placement'))
             self.useFixture(nova_fixtures.DefaultFlavorsFixture())
         elif not self.USES_DB_SELF:
             self.useFixture(nova_fixtures.DatabasePoisonFixture())

nova/tests/fixtures.py

@@ -43,7 +43,7 @@ from nova.tests.functional.api import client
 _TRUE_VALUES = ('True', 'true', '1', 'yes')
 
 CONF = cfg.CONF
-DB_SCHEMA = {'main': "", 'api': "", 'placement': ""}
+DB_SCHEMA = {'main': "", 'api': ""}
 SESSION_CONFIGURED = False
 
 
@@ -221,7 +221,7 @@ class Database(fixtures.Fixture):
     def __init__(self, database='main', connection=None):
         """Create a database fixture.
 
-        :param database: The type of database, 'main', 'api' or 'placement'
+        :param database: The type of database, 'main' or 'api'
         :param connection: The connection string to use
         """
         super(Database, self).__init__()
@@ -242,8 +242,6 @@ class Database(fixtures.Fixture):
                 self.get_engine = session.get_engine
         elif database == 'api':
             self.get_engine = session.get_api_engine
-        elif database == 'placement':
-            self.get_engine = session.get_placement_engine
 
     def _cache_schema(self):
         global DB_SCHEMA
@@ -277,7 +275,7 @@ class DatabaseAtVersion(fixtures.Fixture):
         """Create a database fixture.
 
         :param version: Max version to sync to (or None for current)
-        :param database: The type of database, 'main', 'api', 'placement'
+        :param database: The type of database, 'main' or 'api'
         """
         super(DatabaseAtVersion, self).__init__()
         self.database = database
@@ -286,8 +284,6 @@ class DatabaseAtVersion(fixtures.Fixture):
             self.get_engine = session.get_engine
         elif database == 'api':
             self.get_engine = session.get_api_engine
-        elif database == 'placement':
-            self.get_engine = session.get_placement_engine
 
     def cleanup(self):
         engine = self.get_engine()

nova/tests/functional/api/openstack/placement/fixtures.py

@@ -49,13 +49,11 @@ class APIFixture(fixture.GabbiFixture):
         config.parse_args([], default_config_files=None, configure_db=False,
                           init_rpc=False)
 
-        self.placement_db_fixture = fixtures.Database('placement')
         # NOTE(cdent): api and main database are not used but we still need
         # to manage them to make the fixtures work correctly and not cause
         # conflicts with other tests in the same process.
         self.api_db_fixture = fixtures.Database('api')
         self.main_db_fixture = fixtures.Database('main')
-        self.placement_db_fixture.reset()
         self.api_db_fixture.reset()
         self.main_db_fixture.reset()
 
@@ -63,7 +61,6 @@ class APIFixture(fixture.GabbiFixture):
         os.environ['RP_NAME'] = uuidutils.generate_uuid()
 
     def stop_fixture(self):
-        self.placement_db_fixture.cleanup()
         self.api_db_fixture.cleanup()
         self.main_db_fixture.cleanup()
         if self.conf: