Merge "Filter the 'leader' member from cluster membership list"

astara/coordination.py

@@ -103,7 +103,7 @@ class RugCoordinator(object):
         self._coordinator.watch_join_group(self.group, self.cluster_changed)
         self._coordinator.watch_leave_group(self.group, self.cluster_changed)
         self._coordinator.heartbeat()
-        LOG.debug("Sending initial event changed for members; %s" %
+        LOG.debug("Sending initial event changed for members: %s" %
                   self.members)
         self.cluster_changed(event=None, node_bootstrap=True)
 
@@ -139,7 +139,16 @@ class RugCoordinator(object):
     @property
     def members(self):
         """Returns the current cluster membership list"""
-        return self._coordinator.get_members(self.group).get()
+        members = self._coordinator.get_members(self.group).get()
+
+        # tooz ZK driver reports 'leader' as a member, which can screw with
+        # hashing.
+        try:
+            members.remove('leader')
+        except ValueError:
+            pass
+
+        return members
 
     @property
     def is_leader(self):

astara/test/unit/test_coordination.py

@@ -107,6 +107,24 @@ class TestRugCoordinator(base.RugTestBase):
         self.assertEqual(self.coordinator.members, ['foo', 'bar'])
         self.fake_coord.get_members.assert_called_with(self.coordinator.group)
 
+    def test_members_filter_leader(self):
+        fake_async_resp = mock.MagicMock(
+            get=mock.MagicMock(return_value=['foo', 'bar', 'leader'])
+        )
+        self.fake_coord.get_members.return_value = fake_async_resp
+        self.coordinator = coordination.RugCoordinator(self.queue)
+        self.assertEqual(self.coordinator.members, ['foo', 'bar'])
+        self.fake_coord.get_members.assert_called_with(self.coordinator.group)
+
+    def test_members_filter_no_leader(self):
+        fake_async_resp = mock.MagicMock(
+            get=mock.MagicMock(return_value=['foo', 'bar'])
+        )
+        self.fake_coord.get_members.return_value = fake_async_resp
+        self.coordinator = coordination.RugCoordinator(self.queue)
+        self.assertEqual(self.coordinator.members, ['foo', 'bar'])
+        self.fake_coord.get_members.assert_called_with(self.coordinator.group)
+
     def test_is_leader(self):
         fake_async_resp = mock.MagicMock(
             get=mock.MagicMock(return_value='foo_host')

releasenotes/notes/ignore_zk_leadership_member-2cf3736e67d19b27.yaml

@@ -0,0 +1,3 @@
+---
+fixes:
+  - Bug `1535857 <https://bugs.launchpad.net/astara/+bug/1535857/>`_ The additional \"leadership\" member reported by zookeeper is now ignored to avoid hashing resources to a non-existent node.