Remove availability_zones from service table

This is the final step in enabling availability_zones using aggregate
metadata. Previously all services had an availability_zone, but the
availability_zone is only used for nova-compute.  Services such as
nova-scheduler, nova-network, nova-conductor have always spanned all
availability_zones.

After this change only compute nodes (nova-compute), will have an
availability_zone. In order to preserve current APIs, when running:
* nova host-list (os-hosts)
* euca-describe-availability-zones verbose
* nova-manage service list
Internal services will appear in there own internal availability_zone
(CONF.internal_service_availability_zone)
Internal zone is hidden in euca-describe-availability_zones
(non-verbose)

CONF.node_availability_zone has been renamed to
CONF.default_availability_zone and is only used by the nova-api and
nova-scheduler. CONF.node_availability_zone still works but is
deprecated

DocImpact

Completes blueprint aggregate-based-availability-zones

Change-Id: Ib772df5f9ac2865f20df479f8ddce575a9ce3aff

3 files changed, 87 insertions, 3 deletions

diff --git a/nova/db/api.py b/nova/db/api.py
index 8d93701c8..7f202862e 100644
--- a/nova/db/api.py
+++ b/nova/db/api.py
@@ -1546,8 +1546,10 @@ def aggregate_metadata_get_by_host(context, host, key=None):
 def aggregate_host_get_by_metadata_key(context, key):
     """Get hosts with a specific metadata key metadata for all aggregates.
 
-    Returns a dictionary where each key is a hostname and each value is the
-    key value"""
+    Returns a dictionary where each key is a hostname and each value is a set
+    of the key values
+    return value:  {machine: set( az1, az2 )}
+    """
     return IMPL.aggregate_host_get_by_metadata_key(context, key)
 
 
diff --git a/nova/db/sqlalchemy/migrate_repo/versions/147_no_service_zones.py b/nova/db/sqlalchemy/migrate_repo/versions/147_no_service_zones.py
new file mode 100644
index 000000000..a20799fbe
--- /dev/null
+++ b/nova/db/sqlalchemy/migrate_repo/versions/147_no_service_zones.py
@@ -0,0 +1,83 @@
+# Copyright 2012 OpenStack LLC.
+#
+#    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 String, Column, MetaData, Table, select
+
+from nova.openstack.common import log as logging
+
+LOG = logging.getLogger(__name__)
+
+
+""" Remove availability_zone column from services model and replace with
+    aggregate based zone."""
+
+
+def upgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+
+    services = Table('services', meta, autoload=True)
+    aggregates = Table('aggregates', meta, autoload=True)
+    aggregate_metadata = Table('aggregate_metadata', meta, autoload=True)
+    # migrate data
+    record_list = list(services.select().execute())
+    for rec in record_list:
+        # Only need to migrate nova-compute availability_zones
+        if rec['binary'] != 'nova-compute':
+            continue
+        # if zone doesn't exist create
+        result = aggregate_metadata.select().where(aggregate_metadata.c.key ==
+                'availability_zone' and
+            aggregate_metadata.c.key == rec['availability_zone']).execute()
+        result = [r for r in result]
+        if len(result) > 0:
+            agg_id = result[0].aggregate_id
+        else:
+            agg = aggregates.insert()
+            result = agg.execute({'name': rec['availability_zone']})
+            agg_id = result.inserted_primary_key[0]
+            row = aggregate_metadata.insert()
+            row.execute({'created_at': rec['created_at'],
+                        'updated_at': rec['updated_at'],
+                        'deleted_at': rec['deleted_at'],
+                        'deleted': rec['deleted'],
+                        'key': 'availability_zone',
+                        'value': rec['availability_zone'],
+                        'aggregate_id': agg_id,
+                        })
+        # add host to zone
+        agg_hosts = Table('aggregate_hosts', meta, autoload=True)
+        row = agg_hosts.insert()
+        row.execute({'host': rec['host'], 'aggregate_id': agg_id})
+
+    services.drop_column('availability_zone')
+
+
+def downgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+
+    services = Table('services', meta, autoload=True)
+    aggregate_metadata = Table('aggregate_metadata', meta, autoload=True)
+    agg_hosts = Table('aggregate_hosts', meta, autoload=True)
+    availability_zone = Column('availability_zone', String(255),
+            default='nova')
+    services.create_column(availability_zone)
+    # migrate data
+    services.update().values(availability_zone=select(
+        [aggregate_metadata.c.value]).
+        where(agg_hosts.c.aggregate_id == aggregate_metadata.c.aggregate_id).
+        where(aggregate_metadata.c.key == 'availability_zone').
+        where(agg_hosts.c.host == services.c.host).
+        where(services.c.binary == 'nova-compute')).execute()
diff --git a/nova/db/sqlalchemy/models.py b/nova/db/sqlalchemy/models.py
index 8a161efdf..2d3e23c26 100644
--- a/nova/db/sqlalchemy/models.py
+++ b/nova/db/sqlalchemy/models.py
@@ -106,7 +106,6 @@ class Service(BASE, NovaBase):
     topic = Column(String(255))
     report_count = Column(Integer, nullable=False, default=0)
     disabled = Column(Boolean, default=False)
-    availability_zone = Column(String(255), default='nova')
 
 
 class ComputeNode(BASE, NovaBase):