Always load database graph snapshot on restart

Depends-On: Ia4ee9c34bb68f3b6821ef752893f3a98d4bafc24
Depends-On: Id8f1d77802c0071df778f4a9b7fb0a25c473cf9c
Change-Id: I703083ea337447439ca80c2468f2f47cf18735e0

vitrage/entity_graph/graph_persistency.py

@@ -11,8 +11,6 @@
 # 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 datetime import timedelta
-
 from oslo_log import log
 
 from vitrage.common.constants import VertexProperties as VProps
@@ -20,13 +18,10 @@ from vitrage.graph import Edge
 from vitrage.graph import Vertex
 
 from vitrage.storage.sqlalchemy import models
-from vitrage.utils.datetime import utcnow
 
 
 LOG = log.getLogger(__name__)
 
-EPSILON = 30
-
 
 class GraphPersistency(object):
     def __init__(self, conf, db, graph):
@@ -48,15 +43,8 @@ class GraphPersistency(object):
         except Exception:
             LOG.exception("Graph is not stored")
 
-    def _recent_snapshot_time(self):
-        t = utcnow(with_timezone=False)
-        t = t - timedelta(seconds=3 * self.conf.datasources.snapshots_interval)
-        t = t - timedelta(seconds=EPSILON)
-        return t
-
     def query_recent_snapshot(self):
-        timestamp = self._recent_snapshot_time()
-        return self.db.graph_snapshots.query(timestamp=timestamp)
+        return self.db.graph_snapshots.query()
 
     def replay_events(self, graph, event_id):
         LOG.info('Getting events from database')

vitrage/storage/base.py

@@ -236,8 +236,8 @@ class GraphSnapshotsConnection(object):
         """
         raise NotImplementedError('update graph snapshot not implemented')
 
-    def query(self, timestamp=None):
-        """Yields latest graph snapshot taken until timestamp.
+    def query(self):
+        """Yields latest graph snapshot
 
         :rtype: vitrage.storage.sqlalchemy.models.GraphSnapshot
         """

vitrage/storage/impl_sqlalchemy.py

@@ -20,7 +20,6 @@ from oslo_log import log
 from sqlalchemy import and_
 from sqlalchemy.engine import url as sqlalchemy_url
 from sqlalchemy import func
-from sqlalchemy import or_
 
 from vitrage.common.exception import VitrageInputError
 from vitrage.entity_graph.mappings.operational_alarm_severity import \
@@ -373,11 +372,8 @@ class GraphSnapshotsConnection(base.GraphSnapshotsConnection, BaseTableConn):
         with session.begin():
             session.merge(graph_snapshot)
 
-    def query(self, timestamp=None):
+    def query(self):
         query = self.query_filter(models.GraphSnapshot)
-        query = query.filter(
-            or_(models.GraphSnapshot.updated_at >= timestamp,
-                models.GraphSnapshot.created_at >= timestamp))
         return query.first()
 
     def query_snapshot_event_id(self):

vitrage/tests/functional/entity_graph/graph_persistor/test_graph_persistor.py

@@ -11,8 +11,6 @@
 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations
 # under the License.
-import time
-
 from oslo_config import cfg
 
 from vitrage.common.constants import EdgeProperties
@@ -36,7 +34,6 @@ class TestGraphPersistor(TestFunctionalBase, TestConfiguration):
         cls.conf.register_opts(cls.DATASOURCES_OPTS, group='datasources')
         cls.add_db(cls.conf)
         cls.load_datasources(cls.conf)
-        graph_persistency.EPSILON = 0.1
 
     def test_graph_store_and_query_recent_snapshot(self):
         g = GraphGenerator().create_graph()
@@ -47,11 +44,6 @@ class TestGraphPersistor(TestFunctionalBase, TestConfiguration):
         recovered_graph = self.load_snapshot(recovered_data)
         self.assert_graph_equal(g, recovered_graph)
 
-        time.sleep(graph_persistency.EPSILON + 0.1 +
-                   3 * self.conf.datasources.snapshots_interval)
-        recovered_data = graph_persistor.query_recent_snapshot()
-        self.assertIsNone(recovered_data, 'Should not be a recent snapshot')
-
     def test_event_store_and_replay_events(self):
         g = GraphGenerator().create_graph()
         vertices = g.get_vertices()