Add build_requests database table and model

The build_requests table is a placeholder in the api database that
stores enough information about a boot request to hydrate an Instance if
necessary.  It will be populated early in the boot process so that instance
creation can be deferred until after scheduling.

Partially-implements: bp cells-scheduling-interaction
Change-Id: I8755e57c0ea9afd1c83751dea75cca640e304ab0

nova/db/sqlalchemy/api_migrations/migrate_repo/versions/006_build_request.py

@@ -0,0 +1,68 @@
+#    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.changeset.constraint import ForeignKeyConstraint
+from migrate import UniqueConstraint
+from sqlalchemy import Boolean
+from sqlalchemy import Column
+from sqlalchemy import DateTime
+from sqlalchemy import dialects
+from sqlalchemy import Enum
+from sqlalchemy import Index
+from sqlalchemy import Integer
+from sqlalchemy import MetaData
+from sqlalchemy import String
+from sqlalchemy import Table
+from sqlalchemy import Text
+
+
+def InetSmall():
+    return String(length=39).with_variant(dialects.postgresql.INET(),
+                  'postgresql')
+
+
+def upgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+
+    request_specs = Table('request_specs', meta, autoload=True)
+    build_requests = Table('build_requests', meta,
+        Column('created_at', DateTime),
+        Column('updated_at', DateTime),
+        Column('id', Integer, primary_key=True, nullable=False),
+        Column('request_spec_id', Integer, nullable=False),
+        Column('project_id', String(length=255), nullable=False),
+        Column('user_id', String(length=255), nullable=False),
+        Column('display_name', String(length=255)),
+        Column('instance_metadata', Text),
+        Column('progress', Integer),
+        Column('vm_state', String(length=255)),
+        Column('task_state', String(length=255)),
+        Column('image_ref', String(length=255)),
+        Column('access_ip_v4', InetSmall()),
+        Column('access_ip_v6', InetSmall()),
+        Column('info_cache', Text),
+        Column('security_groups', Text, nullable=False),
+        Column('config_drive', Boolean, default=False, nullable=False),
+        Column('key_name', String(length=255)),
+        Column('locked_by', Enum('owner', 'admin',
+            name='build_requests0locked_by')),
+        UniqueConstraint('request_spec_id',
+            name='uniq_build_requests0request_spec_id'),
+        Index('build_requests_project_id_idx', 'project_id'),
+        ForeignKeyConstraint(columns=['request_spec_id'],
+            refcolumns=[request_specs.c.id]),
+        mysql_engine='InnoDB',
+        mysql_charset='utf8'
+    )
+
+    build_requests.create(checkfirst=True)

nova/db/sqlalchemy/api_models.py

@@ -14,15 +14,19 @@
 from oslo_db.sqlalchemy import models
 from sqlalchemy import Boolean
 from sqlalchemy import Column
+from sqlalchemy import Enum
 from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy import Float
 from sqlalchemy import ForeignKey
 from sqlalchemy import Index
 from sqlalchemy import Integer
+from sqlalchemy import orm
 from sqlalchemy import schema
 from sqlalchemy import String
 from sqlalchemy import Text
 
+from nova.db.sqlalchemy import types
+
 
 class _NovaAPIBase(models.ModelBase, models.TimestampMixin):
     pass
@@ -134,3 +138,36 @@ class FlavorProjects(API_BASE):
     id = Column(Integer, primary_key=True)
     flavor_id = Column(Integer, ForeignKey('flavors.id'), nullable=False)
     project_id = Column(String(255), nullable=False)
+
+
+class BuildRequest(API_BASE):
+    """Represents the information passed to the scheduler."""
+
+    __tablename__ = 'build_requests'
+    __table_args__ = (
+        Index('build_requests_project_id_idx', 'project_id'),
+        schema.UniqueConstraint('request_spec_id',
+            name='uniq_build_requests0request_spec_id')
+        )
+
+    id = Column(Integer, primary_key=True)
+    request_spec_id = Column(Integer, ForeignKey('request_specs.id'),
+            nullable=False)
+    request_spec = orm.relationship(RequestSpec,
+            foreign_keys=request_spec_id,
+            primaryjoin=request_spec_id == RequestSpec.id)
+    project_id = Column(String(255), nullable=False)
+    user_id = Column(String(255), nullable=False)
+    display_name = Column(String(255))
+    instance_metadata = Column(Text)
+    progress = Column(Integer)
+    vm_state = Column(String(255))
+    task_state = Column(String(255))
+    image_ref = Column(String(255))
+    access_ip_v4 = Column(types.IPAddress())
+    access_ip_v6 = Column(types.IPAddress())
+    info_cache = Column(Text)
+    security_groups = Column(Text, nullable=False)
+    config_drive = Column(Boolean, default=False, nullable=False)
+    key_name = Column(String(255))
+    locked_by = Column(Enum('owner', 'admin'))