Add a get_by_uuid for aggregates

db.api.aggregate_get_by_uuid and objects.Aggregate.get_by_uuid
methods are added to make it possible to work with Aggregates by
their newly added uuid attribute.

Partially-Implements: blueprint generic-resource-pools
Change-Id: I7c46fd1ffebb6907c949cfa302131bfbfcd433de

nova/db/api.py

@@ -1792,6 +1792,11 @@ def aggregate_get_by_host(context, host, key=None):
     return IMPL.aggregate_get_by_host(context, host, key)
 
 
+def aggregate_get_by_uuid(context, uuid):
+    """Get a specific aggregate by uuid."""
+    return IMPL.aggregate_get_by_uuid(context, uuid)
+
+
 def aggregate_metadata_get_by_host(context, host, key=None):
     """Get metadata for all aggregates that host belongs to.
 

nova/db/sqlalchemy/api.py

@@ -5661,6 +5661,20 @@ def aggregate_get(context, aggregate_id):
     return aggregate
 
 
+@main_context_manager.reader
+def aggregate_get_by_uuid(context, uuid):
+    query = _aggregate_get_query(context,
+                                 models.Aggregate,
+                                 models.Aggregate.uuid,
+                                 uuid)
+    aggregate = query.first()
+
+    if not aggregate:
+        raise exception.AggregateNotFound(aggregate_id=uuid)
+
+    return aggregate
+
+
 @main_context_manager.reader
 def aggregate_get_by_host(context, host, key=None):
     """Return rows that match host (mandatory) and metadata key (optional).

nova/objects/aggregate.py

@@ -52,7 +52,8 @@ class Aggregate(base.NovaPersistentObject, base.NovaObject):
     # Version 1.0: Initial version
     # Version 1.1: String attributes updated to support unicode
     # Version 1.2: Added uuid field
-    VERSION = '1.2'
+    # Version 1.3: Added get_by_uuid method
+    VERSION = '1.3'
 
     fields = {
         'id': fields.IntegerField(),
@@ -118,6 +119,11 @@ class Aggregate(base.NovaPersistentObject, base.NovaObject):
             db_aggregate = db.aggregate_get(context, aggregate_id)
         return cls._from_db_object(context, cls(), db_aggregate)
 
+    @base.remotable_classmethod
+    def get_by_uuid(cls, context, aggregate_uuid):
+        db_aggregate = db.aggregate_get_by_uuid(context, aggregate_uuid)
+        return cls._from_db_object(context, cls(), db_aggregate)
+
     @base.remotable
     def create(self):
         if self.obj_attr_is_set('id'):

nova/tests/unit/db/test_db_api.py

@@ -620,6 +620,13 @@ class AggregateDBApiTestCase(test.TestCase):
                           db.aggregate_get,
                           ctxt, aggregate_id)
 
+    def test_aggregate_get_by_uuid_raise_not_found(self):
+        ctxt = context.get_admin_context()
+        aggregate_uuid = uuidsentinel.missing_aggregate_uuid
+        self.assertRaises(exception.AggregateNotFound,
+                          db.aggregate_get_by_uuid,
+                          ctxt, aggregate_uuid)
+
     def test_aggregate_metadata_get_raise_not_found(self):
         ctxt = context.get_admin_context()
         # this does not exist!
@@ -656,6 +663,13 @@ class AggregateDBApiTestCase(test.TestCase):
         self.assertEqual(_get_fake_aggr_hosts(), expected['hosts'])
         self.assertEqual(_get_fake_aggr_metadata(), expected['metadetails'])
 
+    def test_aggregate_get_by_uuid(self):
+        ctxt = context.get_admin_context()
+        result = _create_aggregate_with_hosts(context=ctxt)
+        expected = db.aggregate_get_by_uuid(ctxt, result['uuid'])
+        self.assertEqual(_get_fake_aggr_hosts(), expected['hosts'])
+        self.assertEqual(_get_fake_aggr_metadata(), expected['metadetails'])
+
     def test_aggregate_get_by_host(self):
         ctxt = context.get_admin_context()
         values2 = {'name': 'fake_aggregate2'}

nova/tests/unit/objects/test_aggregate.py

@@ -192,6 +192,14 @@ class _TestAggregateObject(object):
             self.assertEqual(uuid, obj.uuid)
             mock_save.assert_called_once_with()
 
+    @mock.patch('nova.db.aggregate_get_by_uuid')
+    def test_get_by_uuid(self, get_by_uuid):
+        get_by_uuid.return_value = fake_aggregate
+        agg = aggregate.Aggregate.get_by_uuid(self.context,
+                                              uuidsentinel.fake_aggregate)
+        self.assertEqual(uuidsentinel.fake_aggregate, agg.uuid)
+        self.assertEqual(fake_aggregate['id'], agg.id)
+
     def test_create(self):
         self.mox.StubOutWithMock(db, 'aggregate_create')
         db.aggregate_create(self.context, {'name': 'foo',

nova/tests/unit/objects/test_objects.py

@@ -1100,7 +1100,7 @@ class TestRegistry(test.NoDBTestCase):
 object_data = {
     'Agent': '1.0-c0c092abaceb6f51efe5d82175f15eba',
     'AgentList': '1.0-5a7380d02c3aaf2a32fc8115ae7ca98c',
-    'Aggregate': '1.2-fe9d8c93feb37919753e9e44fe6818a7',
+    'Aggregate': '1.3-f315cb68906307ca2d1cca84d4753585',
     'AggregateList': '1.2-fb6e19f3c3a3186b04eceb98b5dadbfa',
     'BandwidthUsage': '1.2-c6e4c779c7f40f2407e3d70022e3cd1c',
     'BandwidthUsageList': '1.2-5fe7475ada6fe62413cbfcc06ec70746',