From 3a01e33d7e4426426d913b480d202e21cdc83ae3 Mon Sep 17 00:00:00 2001
From: Matt Riedemann <mriedem.os@gmail.com>
Date: Wed, 19 Apr 2017 10:00:53 -0400
Subject: [PATCH] Add online data migration for populating services.uuid

This adds the online data migration for populating the
services.uuid column on older records.

Part of blueprint service-hyper-uuid-in-api

Change-Id: I6baf546d7075f7671df0abeb1e7d68372fd177ed
---
 nova/cmd/manage.py                            |  2 +
 nova/db/api.py                                |  4 ++
 nova/db/sqlalchemy/api.py                     | 18 +++++++++
 nova/tests/unit/db/test_db_api.py             | 37 +++++++++++++++++++
 ...uid-online-migration-17d48f198a6d4deb.yaml |  6 +++
 5 files changed, 67 insertions(+)
 create mode 100644 releasenotes/notes/service-uuid-online-migration-17d48f198a6d4deb.yaml

diff --git a/nova/cmd/manage.py b/nova/cmd/manage.py
index a3aad09054bc..06119cd8d7d9 100644
--- a/nova/cmd/manage.py
+++ b/nova/cmd/manage.py
@@ -620,6 +620,8 @@ class DbCommands(object):
         # NOTE(mriedem): This online migration is going to be backported to
         # Newton also since it's an upgrade issue when upgrading from Mitaka.
         build_request_obj.delete_build_requests_with_no_instance_uuid,
+        # Added in Pike
+        db.service_uuids_online_data_migration,
     )
 
     def __init__(self):
diff --git a/nova/db/api.py b/nova/db/api.py
index 377178404bbf..83d7b10b1846 100644
--- a/nova/db/api.py
+++ b/nova/db/api.py
@@ -2057,6 +2057,10 @@ def pcidevice_online_data_migration(context, max_count):
     return IMPL.pcidevice_online_data_migration(context, max_count)
 
 
+def service_uuids_online_data_migration(context, max_count):
+    return IMPL.service_uuids_online_data_migration(context, max_count)
+
+
 ####################
 
 
diff --git a/nova/db/sqlalchemy/api.py b/nova/db/sqlalchemy/api.py
index 4980917378b9..a5c0720d1769 100644
--- a/nova/db/sqlalchemy/api.py
+++ b/nova/db/sqlalchemy/api.py
@@ -6524,6 +6524,24 @@ def archive_deleted_rows(max_rows=None):
     return table_to_rows_archived
 
 
+@pick_context_manager_writer
+def service_uuids_online_data_migration(context, max_count):
+    from nova.objects import service
+
+    count_all = 0
+    count_hit = 0
+
+    db_services = model_query(context, models.Service).filter_by(
+        uuid=None).limit(max_count)
+    for db_service in db_services:
+        count_all += 1
+        service_obj = service.Service._from_db_object(
+            context, service.Service(), db_service)
+        if 'uuid' in service_obj:
+            count_hit += 1
+    return count_all, count_hit
+
+
 ####################
 
 
diff --git a/nova/tests/unit/db/test_db_api.py b/nova/tests/unit/db/test_db_api.py
index 251a6def79db..33af2d768472 100644
--- a/nova/tests/unit/db/test_db_api.py
+++ b/nova/tests/unit/db/test_db_api.py
@@ -3764,6 +3764,43 @@ class ServiceTestCase(test.TestCase, ModelsObjectComparatorMixin):
         self.assertRaises(exception.ServiceTopicExists, db.service_create,
                           self.ctxt, values)
 
+    def test_migrate_service_uuids(self):
+        # Start with nothing.
+        total, done = db.service_uuids_online_data_migration(self.ctxt, 10)
+        self.assertEqual(0, total)
+        self.assertEqual(0, done)
+
+        # Create two services, one with a uuid and one without.
+        db.service_create(self.ctxt,
+                          dict(host='host1', binary='nova-compute',
+                               topic='compute', report_count=1,
+                               disabled=False))
+        db.service_create(self.ctxt,
+                          dict(host='host2', binary='nova-compute',
+                               topic='compute', report_count=1,
+                               disabled=False, uuid=uuidsentinel.host2))
+
+        # Now migrate them, we should find one and update one.
+        total, done = db.service_uuids_online_data_migration(
+            self.ctxt, 10)
+        self.assertEqual(1, total)
+        self.assertEqual(1, done)
+
+        # Get the services back to make sure the original uuid didn't change.
+        services = db.service_get_all_by_binary(self.ctxt, 'nova-compute')
+        self.assertEqual(2, len(services))
+        for service in services:
+            if service['host'] == 'host2':
+                self.assertEqual(uuidsentinel.host2, service['uuid'])
+            else:
+                self.assertIsNotNone(service['uuid'])
+
+        # Run the online migration again to see nothing was processed.
+        total, done = db.service_uuids_online_data_migration(
+            self.ctxt, 10)
+        self.assertEqual(0, total)
+        self.assertEqual(0, done)
+
 
 class BaseInstanceTypeTestCase(test.TestCase, ModelsObjectComparatorMixin):
     def setUp(self):
diff --git a/releasenotes/notes/service-uuid-online-migration-17d48f198a6d4deb.yaml b/releasenotes/notes/service-uuid-online-migration-17d48f198a6d4deb.yaml
new file mode 100644
index 000000000000..b13c4e1033aa
--- /dev/null
+++ b/releasenotes/notes/service-uuid-online-migration-17d48f198a6d4deb.yaml
@@ -0,0 +1,6 @@
+---
+upgrade:
+  - |
+    An online data migration has been added to populate the ``services.uuid``
+    column in the nova database for non-deleted services records. Listing or
+    showing services out of the ``os-services`` API will have the same effect.