Add instance/instance_uuid to build_requests table

New fields keep needing to be added to build_requests in order to
capture all of the relevant instance information necessary. At this
point it's simpler to just embed a serialized Instance object in the db.
A column for that is added, as well as an instance_uuid column for
indexed lookups.

Change-Id: I1628ddd8cb75b4d0a7bbcd2720536c2e0bfc6043
Partially-implements: bp add-buildrequest-obj

nova/db/sqlalchemy/api_migrations/migrate_repo/versions/013_build_request_extended_attrs.py

@@ -0,0 +1,52 @@
+#    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.
+
+from migrate import UniqueConstraint
+from sqlalchemy import Column
+from sqlalchemy.engine import reflection
+from sqlalchemy import Index
+from sqlalchemy import MetaData
+from sqlalchemy import String
+from sqlalchemy import Table
+from sqlalchemy import Text
+
+
+def upgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+
+    build_requests = Table('build_requests', meta, autoload=True)
+
+    columns_to_add = [
+            ('instance_uuid',
+                Column('instance_uuid', String(length=36))),
+            ('instance',
+                Column('instance', Text())),
+    ]
+    for (col_name, column) in columns_to_add:
+        if not hasattr(build_requests.c, col_name):
+            build_requests.create_column(column)
+
+    for index in build_requests.indexes:
+        if [c.name for c in index.columns] == ['instance_uuid']:
+            break
+    else:
+        index = Index('build_requests_instance_uuid_idx',
+                build_requests.c.instance_uuid)
+        index.create()
+
+    inspector = reflection.Inspector.from_engine(migrate_engine)
+    constrs = inspector.get_unique_constraints('build_requests')
+    constr_names = [constr['name'] for constr in constrs]
+    if 'uniq_build_requests0instance_uuid' not in constr_names:
+        UniqueConstraint('instance_uuid', table=build_requests,
+                name='uniq_build_requests0instance_uuid').create()

nova/db/sqlalchemy/api_models.py

@@ -168,7 +168,10 @@ class BuildRequest(API_BASE):
 
     __tablename__ = 'build_requests'
     __table_args__ = (
+        Index('build_requests_instance_uuid_idx', 'instance_uuid'),
         Index('build_requests_project_id_idx', 'project_id'),
+        schema.UniqueConstraint('instance_uuid',
+            name='uniq_build_requests0instance_uuid'),
         schema.UniqueConstraint('request_spec_id',
             name='uniq_build_requests0request_spec_id')
         )
@@ -180,6 +183,7 @@ class BuildRequest(API_BASE):
             foreign_keys=request_spec_id,
             back_populates='build_request',
             primaryjoin=request_spec_id == RequestSpec.id)
+    instance_uuid = Column(String(36))
     project_id = Column(String(255), nullable=False)
     user_id = Column(String(255), nullable=False)
     display_name = Column(String(255))
@@ -195,3 +199,4 @@ class BuildRequest(API_BASE):
     config_drive = Column(Boolean, default=False, nullable=False)
     key_name = Column(String(255))
     locked_by = Column(Enum('owner', 'admin'))
+    instance = Column(Text)