Remove instance Foreign Key in volumes table, replace with instance_uuid

* Remove the instance relationship and instance_id FK
* Add instance_uuuid column to volumes table
* Passed unit tests and devstack tests

Change-Id: Id598f1f1d7915d1af6bf3dd75e5819dce08aaa0f

6 files changed, 373 insertions, 34 deletions

diff --git a/nova/db/api.py b/nova/db/api.py
index 93eea8f10..ca1e420d7 100644
--- a/nova/db/api.py
+++ b/nova/db/api.py
@@ -986,9 +986,9 @@ def volume_get_all_by_host(context, host):
     return IMPL.volume_get_all_by_host(context, host)
 
 
-def volume_get_all_by_instance(context, instance_id):
+def volume_get_all_by_instance_uuid(context, instance_uuid):
     """Get all volumes belonging to a instance."""
-    return IMPL.volume_get_all_by_instance(context, instance_id)
+    return IMPL.volume_get_all_by_instance_uuid(context, instance_uuid)
 
 
 def volume_get_all_by_project(context, project_id):
@@ -1001,11 +1001,6 @@ def volume_get_by_ec2_id(context, ec2_id):
     return IMPL.volume_get_by_ec2_id(context, ec2_id)
 
 
-def volume_get_instance(context, volume_id):
-    """Get the instance that a volume is attached to."""
-    return IMPL.volume_get_instance(context, volume_id)
-
-
 def volume_get_iscsi_target_num(context, volume_id):
     """Get the target num (tid) allocated to the volume."""
     return IMPL.volume_get_iscsi_target_num(context, volume_id)
diff --git a/nova/db/sqlalchemy/api.py b/nova/db/sqlalchemy/api.py
index 46e080578..f6af98d68 100644
--- a/nova/db/sqlalchemy/api.py
+++ b/nova/db/sqlalchemy/api.py
@@ -1374,7 +1374,6 @@ def _build_instance_get(context, session=None):
                         project_only=True).\
             options(joinedload_all('security_groups.rules')).\
             options(joinedload('info_cache')).\
-            options(joinedload('volumes')).\
             options(joinedload('metadata')).\
             options(joinedload('instance_type'))
 
@@ -2402,15 +2401,17 @@ def volume_allocate_iscsi_target(context, volume_id, host):
 
 
 @require_admin_context
-def volume_attached(context, volume_id, instance_id, mountpoint):
+def volume_attached(context, volume_id, instance_uuid, mountpoint):
+    if not utils.is_uuid_like(instance_uuid):
+        raise exception.InvalidUUID(instance_uuid)
+
     session = get_session()
     with session.begin():
         volume_ref = volume_get(context, volume_id, session=session)
         volume_ref['status'] = 'in-use'
         volume_ref['mountpoint'] = mountpoint
         volume_ref['attach_status'] = 'attached'
-        volume_ref.instance = instance_get(context, instance_id,
-                                           session=session)
+        volume_ref['instance_uuid'] = instance_uuid
         volume_ref.save(session=session)
 
 
@@ -2471,7 +2472,7 @@ def volume_detached(context, volume_id):
         volume_ref['status'] = 'available'
         volume_ref['mountpoint'] = None
         volume_ref['attach_status'] = 'detached'
-        volume_ref.instance = None
+        volume_ref['instance_uuid'] = None
         volume_ref.save(session=session)
 
 
@@ -2479,9 +2480,8 @@ def volume_detached(context, volume_id):
 def _volume_get_query(context, session=None, project_only=False):
     return model_query(context, models.Volume, session=session,
                        project_only=project_only).\
-                     options(joinedload('instance')).\
-                     options(joinedload('volume_metadata')).\
-                     options(joinedload('volume_type'))
+                       options(joinedload('volume_metadata')).\
+                       options(joinedload('volume_type'))
 
 
 @require_context
@@ -2519,15 +2519,15 @@ def volume_get_all_by_host(context, host):
 
 
 @require_admin_context
-def volume_get_all_by_instance(context, instance_id):
+def volume_get_all_by_instance_uuid(context, instance_uuid):
     result = model_query(context, models.Volume, read_deleted="no").\
                      options(joinedload('volume_metadata')).\
                      options(joinedload('volume_type')).\
-                     filter_by(instance_id=instance_id).\
+                     filter_by(instance_uuid=instance_uuid).\
                      all()
 
     if not result:
-        raise exception.VolumeNotFoundForInstance(instance_id=instance_id)
+        return []
 
     return result
 
@@ -2539,16 +2539,6 @@ def volume_get_all_by_project(context, project_id):
 
 
 @require_admin_context
-def volume_get_instance(context, volume_id):
-    result = _volume_get_query(context).filter_by(id=volume_id).first()
-
-    if not result:
-        raise exception.VolumeNotFound(volume_id=volume_id)
-
-    return result.instance
-
-
-@require_admin_context
 def volume_get_iscsi_target_num(context, volume_id):
     result = model_query(context, models.IscsiTarget, read_deleted="yes").\
                      filter_by(volume_id=volume_id).\
diff --git a/nova/db/sqlalchemy/migrate_repo/versions/095_change_fk_instance_id_to_uuid.py b/nova/db/sqlalchemy/migrate_repo/versions/095_change_fk_instance_id_to_uuid.py
new file mode 100644
index 000000000..ea8684f3d
--- /dev/null
+++ b/nova/db/sqlalchemy/migrate_repo/versions/095_change_fk_instance_id_to_uuid.py
@@ -0,0 +1,94 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2012 OpenStack LLC.
+# Copyright 2012 SolidFire Inc
+# All Rights Reserved.
+#
+#    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 sqlalchemy import select, Column
+from sqlalchemy import MetaData, Integer, String, Table
+from migrate import ForeignKeyConstraint
+
+from nova import log as logging
+
+
+LOG = logging.getLogger(__name__)
+
+
+def upgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+
+    instances = Table('instances', meta, autoload=True)
+    volumes = Table('volumes', meta, autoload=True)
+    instance_uuid_column = Column('instance_uuid', String(36))
+
+    instance_uuid_column.create(volumes)
+    try:
+        volumes.update().values(
+            instance_uuid=select(
+                [instances.c.uuid],
+                instances.c.id == volumes.c.instance_id)
+                ).execute()
+    except Exception:
+        instance_uuid_column.drop()
+
+    fkeys = list(volumes.c.instance_id.foreign_keys)
+    if fkeys:
+        try:
+            fk_name = fkeys[0].constraint.name
+            ForeignKeyConstraint(
+                columns=[volumes.c.instance_id],
+                refcolumns=[instances.c.id],
+                name=fk_name).drop()
+
+        except Exception:
+            LOG.error(_("foreign key could not be dropped"))
+            raise
+
+    volumes.c.instance_id.drop()
+
+
+def downgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+
+    instances = Table('instances', meta, autoload=True)
+    volumes = Table('volumes', meta, autoload=True)
+    instance_id_column = Column('instance_id', Integer)
+
+    instance_id_column.create(volumes)
+    try:
+        volumes.update().values(
+            instance_id=select(
+                [instances.c.id],
+                instances.c.uuid == volumes.c.instance_uuid)
+                ).execute()
+    except Exception:
+        instance_id_column.drop()
+
+    fkeys = list(volumes.c.instance_id.foreign_keys)
+    if fkeys:
+        try:
+            fk_name = fkeys[0].constraint.name
+            ForeignKeyConstraint(
+                columns=[volumes.c.instance_id],
+                refcolumns=[instances.c.id],
+                name=fk_name).create()
+
+        except Exception:
+            LOG.error(_("foreign key could not be created"))
+            raise
+
+    volumes.c.instance_uuid.drop()
diff --git a/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_downgrade.sql b/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_downgrade.sql
new file mode 100644
index 000000000..7c13455e4
--- /dev/null
+++ b/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_downgrade.sql
@@ -0,0 +1,133 @@
+BEGIN TRANSACTION;
+    -- change instance_id volumes table
+    CREATE TABLE volumes_backup(
+        created_at DATETIME,
+        updated_at DATETIME,
+        deleted_at DATETIME,
+        deleted BOOLEAN,
+        id VARCHAR(36) NOT NULL,
+        ec2_id INTEGER,
+        user_id VARCHAR(255),
+        project_id VARCHAR(255),
+        snapshot_id VARCHAR(36),
+        host VARCHAR(255),
+        size INTEGER,
+        availability_zone VARCHAR(255),
+        instance_id INTEGER,
+        instance_uuid VARCHAR(36),
+        mountpoint VARCHAR(255),
+        attach_time VARCHAR(255),
+        status VARCHAR(255),
+        attach_status VARCHAR(255),
+        scheduled_at DATETIME,
+        launched_at DATETIME,
+        terminated_at DATETIME,
+        display_name VARCHAR(255),
+        display_description VARCHAR(255),
+        provider_location VARCHAR(255),
+        provider_auth VARCHAR(255),
+        volume_type_id INTEGER,
+        PRIMARY KEY (id),
+        FOREIGN KEY(instance_id) REFERENCES instances (id),
+        UNIQUE (id),
+        CHECK (deleted IN (0, 1))
+    );
+
+    INSERT INTO volumes_backup SELECT
+        created_at,
+        updated_at,
+        deleted_at,
+        deleted,
+        id,
+        ec2_id,
+        user_id,
+        project_id,
+        snapshot_id,
+        host,
+        size,
+        availability_zone,
+        NULL,
+        instance_uuid,
+        mountpoint,
+        attach_time,
+        status,
+        attach_status,
+        scheduled_at,
+        launched_at,
+        terminated_at,
+        display_name,
+        display_description,
+        provider_location,
+        provider_auth,
+        volume_type_id
+    FROM volumes;
+
+    UPDATE volumes_backup
+        SET instance_id =
+            (SELECT id
+                FROM instances
+                WHERE volumes_backup.instance_uuid = instances.uuid
+        );
+    DROP TABLE volumes;
+
+    CREATE TABLE volumes(
+        created_at DATETIME,
+        updated_at DATETIME,
+        deleted_at DATETIME,
+        deleted BOOLEAN,
+        id VARCHAR(36) NOT NULL,
+        ec2_id INTEGER,
+        user_id VARCHAR(255),
+        project_id VARCHAR(255),
+        snapshot_id VARCHAR(36),
+        host VARCHAR(255),
+        size INTEGER,
+        availability_zone VARCHAR(255),
+        instance_id INTEGER,
+        mountpoint VARCHAR(255),
+        attach_time VARCHAR(255),
+        status VARCHAR(255),
+        attach_status VARCHAR(255),
+        scheduled_at DATETIME,
+        launched_at DATETIME,
+        terminated_at DATETIME,
+        display_name VARCHAR(255),
+        display_description VARCHAR(255),
+        provider_location VARCHAR(255),
+        provider_auth VARCHAR(255),
+        volume_type_id INTEGER,
+        PRIMARY KEY (id),
+        FOREIGN KEY (instance_id) REFERENCES instances (id),
+        UNIQUE (id),
+        CHECK (deleted IN (0, 1))
+    );
+
+    INSERT INTO volumes
+        SELECT created_at,
+               updated_at,
+               deleted_at,
+               deleted,
+               id,
+               ec2_id,
+               user_id,
+               project_id,
+               snapshot_id,
+               host,
+               size,
+               availability_zone,
+               instance_id,
+               mountpoint,
+               attach_time,
+               status,
+               attach_status,
+               scheduled_at,
+               launched_at,
+               terminated_at,
+               display_name,
+               display_description,
+               provider_location,
+               provider_auth,
+               volume_type_id
+        FROM volumes_backup;
+    DROP TABLE volumes_backup;
+COMMIT;
diff --git a/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_upgrade.sql b/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_upgrade.sql
new file mode 100644
index 000000000..130e11030
--- /dev/null
+++ b/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_upgrade.sql
@@ -0,0 +1,132 @@
+BEGIN TRANSACTION;
+    -- change instance_id volumes table
+    CREATE TABLE volumes_backup(
+        created_at DATETIME,
+        updated_at DATETIME,
+        deleted_at DATETIME,
+        deleted BOOLEAN,
+        id VARCHAR(36) NOT NULL,
+        ec2_id INTEGER,
+        user_id VARCHAR(255),
+        project_id VARCHAR(255),
+        snapshot_id VARCHAR(36),
+        host VARCHAR(255),
+        size INTEGER,
+        availability_zone VARCHAR(255),
+        instance_id INTEGER,
+        instance_uuid VARCHAR(36),
+        mountpoint VARCHAR(255),
+        attach_time VARCHAR(255),
+        status VARCHAR(255),
+        attach_status VARCHAR(255),
+        scheduled_at DATETIME,
+        launched_at DATETIME,
+        terminated_at DATETIME,
+        display_name VARCHAR(255),
+        display_description VARCHAR(255),
+        provider_location VARCHAR(255),
+        provider_auth VARCHAR(255),
+        volume_type_id INTEGER,
+        PRIMARY KEY (id),
+        FOREIGN KEY(instance_id) REFERENCES instances (id),
+        UNIQUE (id),
+        CHECK (deleted IN (0, 1))
+    );
+
+    INSERT INTO volumes_backup SELECT
+        created_at,
+        updated_at,
+        deleted_at,
+        deleted,
+        id,
+        ec2_id,
+        user_id,
+        project_id,
+        snapshot_id,
+        host,
+        size,
+        availability_zone,
+        instance_id,
+        NULL,
+        mountpoint,
+        attach_time,
+        status,
+        attach_status,
+        scheduled_at,
+        launched_at,
+        terminated_at,
+        display_name,
+        display_description,
+        provider_location,
+        provider_auth,
+        volume_type_id
+    FROM volumes;
+
+    UPDATE volumes_backup
+        SET instance_uuid =
+            (SELECT uuid
+                FROM instances
+                WHERE volumes_backup.instance_id = instances.id
+        );
+    DROP TABLE volumes;
+
+    CREATE TABLE volumes(
+        created_at DATETIME,
+        updated_at DATETIME,
+        deleted_at DATETIME,
+        deleted BOOLEAN,
+        id VARCHAR(36) NOT NULL,
+        ec2_id INTEGER,
+        user_id VARCHAR(255),
+        project_id VARCHAR(255),
+        snapshot_id VARCHAR(36),
+        host VARCHAR(255),
+        size INTEGER,
+        availability_zone VARCHAR(255),
+        instance_uuid VARCHAR(36),
+        mountpoint VARCHAR(255),
+        attach_time VARCHAR(255),
+        status VARCHAR(255),
+        attach_status VARCHAR(255),
+        scheduled_at DATETIME,
+        launched_at DATETIME,
+        terminated_at DATETIME,
+        display_name VARCHAR(255),
+        display_description VARCHAR(255),
+        provider_location VARCHAR(255),
+        provider_auth VARCHAR(255),
+        volume_type_id INTEGER,
+        PRIMARY KEY (id),
+        UNIQUE (id),
+        CHECK (deleted IN (0, 1))
+    );
+
+    INSERT INTO volumes
+        SELECT created_at,
+               updated_at,
+               deleted_at,
+               deleted,
+               id,
+               ec2_id,
+               user_id,
+               project_id,
+               snapshot_id,
+               host,
+               size,
+               availability_zone,
+               instance_uuid,
+               mountpoint,
+               attach_time,
+               status,
+               attach_status,
+               scheduled_at,
+               launched_at,
+               terminated_at,
+               display_name,
+               display_description,
+               provider_location,
+               provider_auth,
+               volume_type_id
+        FROM volumes_backup;
+    DROP TABLE volumes_backup;
+COMMIT;
diff --git a/nova/db/sqlalchemy/models.py b/nova/db/sqlalchemy/models.py
index 9007de424..056ecd411 100644
--- a/nova/db/sqlalchemy/models.py
+++ b/nova/db/sqlalchemy/models.py
@@ -341,12 +341,7 @@ class Volume(BASE, NovaBase):
     host = Column(String(255))  # , ForeignKey('hosts.id'))
     size = Column(Integer)
     availability_zone = Column(String(255))  # TODO(vish): foreign key?
-    instance_id = Column(Integer, ForeignKey('instances.id'), nullable=True)
-    instance = relationship(Instance,
-                            backref=backref('volumes'),
-                            foreign_keys=instance_id,
-                            primaryjoin='and_(Volume.instance_id==Instance.id,'
-                                             'Volume.deleted==False)')
+    instance_uuid = Column(String(36))
     mountpoint = Column(String(255))
     attach_time = Column(String(255))  # TODO(vish): datetime
     status = Column(String(255))  # TODO(vish): enum?