Beispiel #1
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    def get_create_member_flow(self):
        """Create a flow to create a member

        :returns: The flow for creating a member
        """
        create_member_flow = linear_flow.Flow(constants.CREATE_MEMBER_FLOW)
        create_member_flow.add(
            lifecycle_tasks.MemberToErrorOnRevertTask(requires=[
                constants.MEMBER, constants.LISTENERS, constants.LOADBALANCER,
                constants.POOL
            ]))
        create_member_flow.add(
            database_tasks.MarkMemberPendingCreateInDB(
                requires=constants.MEMBER))
        create_member_flow.add(
            network_tasks.CalculateDelta(requires=constants.LOADBALANCER,
                                         provides=constants.DELTAS))
        create_member_flow.add(
            network_tasks.HandleNetworkDeltas(requires=constants.DELTAS,
                                              provides=constants.ADDED_PORTS))
        create_member_flow.add(
            amphora_driver_tasks.AmphoraePostNetworkPlug(
                requires=(constants.LOADBALANCER, constants.ADDED_PORTS)))
        create_member_flow.add(
            amphora_driver_tasks.ListenersUpdate(
                requires=(constants.LOADBALANCER, constants.LISTENERS)))
        create_member_flow.add(
            database_tasks.MarkMemberActiveInDB(requires=constants.MEMBER))
        create_member_flow.add(
            database_tasks.MarkPoolActiveInDB(requires=constants.POOL))
        create_member_flow.add(
            database_tasks.MarkLBAndListenersActiveInDB(
                requires=(constants.LOADBALANCER, constants.LISTENERS)))

        return create_member_flow
Beispiel #2
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    def get_create_load_balancer_graph_flows(self, topology, prefix):
        allocate_amphorae_flow = self.get_create_load_balancer_flow(topology)
        f_name = constants.CREATE_LOADBALANCER_GRAPH_FLOW
        lb_create_graph_flow = linear_flow.Flow(f_name)
        lb_create_graph_flow.add(
            self.get_post_lb_amp_association_flow(prefix, topology))
        lb_create_graph_flow.add(
            database_tasks.ReloadLoadBalancer(
                name=constants.RELOAD_LB_AFTER_AMP_ASSOC_FULL_GRAPH,
                requires=constants.LOADBALANCER_ID,
                provides=constants.LOADBALANCER))
        lb_create_graph_flow.add(
            network_tasks.CalculateDelta(requires=constants.LOADBALANCER,
                                         provides=constants.DELTAS))
        lb_create_graph_flow.add(
            network_tasks.HandleNetworkDeltas(requires=constants.DELTAS,
                                              provides=constants.ADDED_PORTS))
        lb_create_graph_flow.add(
            amphora_driver_tasks.AmphoraePostNetworkPlug(
                requires=(constants.LOADBALANCER, constants.ADDED_PORTS)))
        lb_create_graph_flow.add(
            self.listener_flows.get_create_all_listeners_flow())

        lb_create_graph_flow.add(
            database_tasks.MarkLBActiveInDB(mark_listeners=True,
                                            requires=constants.LOADBALANCER))
        return allocate_amphorae_flow, lb_create_graph_flow
Beispiel #3
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 def _create_listeners_flow(self):
     flows = []
     flows.append(
         database_tasks.ReloadLoadBalancer(
             name=constants.RELOAD_LB_AFTER_AMP_ASSOC_FULL_GRAPH,
             requires=constants.LOADBALANCER_ID,
             provides=constants.LOADBALANCER
         )
     )
     flows.append(
         network_tasks.CalculateDelta(
             requires=constants.LOADBALANCER, provides=constants.DELTAS
         )
     )
     flows.append(
         network_tasks.HandleNetworkDeltas(
             requires=constants.DELTAS, provides=constants.ADDED_PORTS
         )
     )
     flows.append(
         amphora_driver_tasks.AmphoraePostNetworkPlug(
             requires=(constants.LOADBALANCER, constants.ADDED_PORTS)
         )
     )
     flows.append(
         self.listener_flows.get_create_all_listeners_flow()
     )
     flows.append(
         database_tasks.MarkLBActiveInDB(
             mark_subobjects=True,
             requires=constants.LOADBALANCER
         )
     )
     return flows
Beispiel #4
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    def get_failover_flow(self, role=constants.ROLE_STANDALONE,
                          status=constants.AMPHORA_READY):
        """Creates a flow to failover a stale amphora

        :returns: The flow for amphora failover
        """

        failover_amphora_flow = linear_flow.Flow(
            constants.FAILOVER_AMPHORA_FLOW)

        failover_amphora_flow.add(lifecycle_tasks.AmphoraToErrorOnRevertTask(
            rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
            requires=constants.AMPHORA))

        # Delete the old amphora
        failover_amphora_flow.add(
            database_tasks.MarkAmphoraPendingDeleteInDB(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA))
        failover_amphora_flow.add(
            database_tasks.MarkAmphoraHealthBusy(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA))
        failover_amphora_flow.add(compute_tasks.ComputeDelete(
            rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
            requires=constants.AMPHORA))
        failover_amphora_flow.add(network_tasks.WaitForPortDetach(
            rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
            requires=constants.AMPHORA))
        failover_amphora_flow.add(
            database_tasks.DisableAmphoraHealthMonitoring(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA))
        failover_amphora_flow.add(database_tasks.MarkAmphoraDeletedInDB(
            rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
            requires=constants.AMPHORA))

        # If this is an unallocated amp (spares pool), we're done
        if status != constants.AMPHORA_ALLOCATED:
            return failover_amphora_flow

        # Save failed amphora details for later
        failover_amphora_flow.add(
            database_tasks.GetAmphoraDetails(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA,
                provides=constants.AMP_DATA))

        # Get a new amphora
        # Note: Role doesn't matter here.  We will update it later.
        get_amp_subflow = self.get_amphora_for_lb_subflow(
            prefix=constants.FAILOVER_AMPHORA_FLOW)
        failover_amphora_flow.add(get_amp_subflow)

        # Update the new amphora with the failed amphora details
        failover_amphora_flow.add(database_tasks.UpdateAmpFailoverDetails(
            requires=(constants.AMPHORA, constants.AMP_DATA)))

        failover_amphora_flow.add(database_tasks.ReloadLoadBalancer(
            requires=constants.LOADBALANCER_ID,
            provides=constants.LOADBALANCER))

        failover_amphora_flow.add(network_tasks.GetAmphoraeNetworkConfigs(
            requires=constants.LOADBALANCER,
            provides=constants.AMPHORAE_NETWORK_CONFIG))
        failover_amphora_flow.add(database_tasks.GetListenersFromLoadbalancer(
            requires=constants.LOADBALANCER, provides=constants.LISTENERS))

        failover_amphora_flow.add(amphora_driver_tasks.ListenersUpdate(
            requires=(constants.LOADBALANCER, constants.LISTENERS)))

        # Plug the VIP ports into the new amphora
        failover_amphora_flow.add(network_tasks.PlugVIPPort(
            requires=(constants.AMPHORA, constants.AMPHORAE_NETWORK_CONFIG)))
        failover_amphora_flow.add(amphora_driver_tasks.AmphoraPostVIPPlug(
            requires=(constants.AMPHORA, constants.LOADBALANCER,
                      constants.AMPHORAE_NETWORK_CONFIG)))

        # Plug the member networks into the new amphora
        failover_amphora_flow.add(network_tasks.CalculateDelta(
            requires=constants.LOADBALANCER, provides=constants.DELTAS))
        failover_amphora_flow.add(network_tasks.HandleNetworkDeltas(
            requires=constants.DELTAS, provides=constants.ADDED_PORTS))
        failover_amphora_flow.add(amphora_driver_tasks.AmphoraePostNetworkPlug(
            requires=(constants.LOADBALANCER, constants.ADDED_PORTS)))

        # Handle the amphora role and VRRP if necessary
        if role == constants.ROLE_MASTER:
            failover_amphora_flow.add(database_tasks.MarkAmphoraMasterInDB(
                name=constants.MARK_AMP_MASTER_INDB,
                requires=constants.AMPHORA))
            vrrp_subflow = self.get_vrrp_subflow(role)
            failover_amphora_flow.add(vrrp_subflow)
        elif role == constants.ROLE_BACKUP:
            failover_amphora_flow.add(database_tasks.MarkAmphoraBackupInDB(
                name=constants.MARK_AMP_BACKUP_INDB,
                requires=constants.AMPHORA))
            vrrp_subflow = self.get_vrrp_subflow(role)
            failover_amphora_flow.add(vrrp_subflow)
        elif role == constants.ROLE_STANDALONE:
            failover_amphora_flow.add(
                database_tasks.MarkAmphoraStandAloneInDB(
                    name=constants.MARK_AMP_STANDALONE_INDB,
                    requires=constants.AMPHORA))

        failover_amphora_flow.add(amphora_driver_tasks.ListenersStart(
            requires=(constants.LOADBALANCER, constants.LISTENERS)))

        return failover_amphora_flow
Beispiel #5
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    def get_batch_update_members_flow(self, old_members, new_members,
                                      updated_members):
        """Create a flow to batch update members

        :returns: The flow for batch updating members
        """
        batch_update_members_flow = linear_flow.Flow(
            constants.BATCH_UPDATE_MEMBERS_FLOW)
        unordered_members_flow = unordered_flow.Flow(
            constants.UNORDERED_MEMBER_UPDATES_FLOW)
        unordered_members_active_flow = unordered_flow.Flow(
            constants.UNORDERED_MEMBER_ACTIVE_FLOW)

        # Delete old members
        unordered_members_flow.add(
            lifecycle_tasks.MembersToErrorOnRevertTask(
                inject={constants.MEMBERS: old_members},
                name='{flow}-deleted'.format(
                    flow=constants.MEMBER_TO_ERROR_ON_REVERT_FLOW)))
        for m in old_members:
            unordered_members_flow.add(
                model_tasks.DeleteModelObject(
                    inject={constants.OBJECT: m},
                    name='{flow}-{id}'.format(
                        id=m.id, flow=constants.DELETE_MODEL_OBJECT_FLOW)))
            unordered_members_flow.add(
                database_tasks.DeleteMemberInDB(
                    inject={constants.MEMBER: m},
                    name='{flow}-{id}'.format(
                        id=m.id, flow=constants.DELETE_MEMBER_INDB)))
            unordered_members_flow.add(
                database_tasks.DecrementMemberQuota(
                    inject={constants.MEMBER: m},
                    name='{flow}-{id}'.format(
                        id=m.id, flow=constants.DECREMENT_MEMBER_QUOTA_FLOW)))

        # Create new members
        unordered_members_flow.add(
            lifecycle_tasks.MembersToErrorOnRevertTask(
                inject={constants.MEMBERS: new_members},
                name='{flow}-created'.format(
                    flow=constants.MEMBER_TO_ERROR_ON_REVERT_FLOW)))
        for m in new_members:
            unordered_members_active_flow.add(
                database_tasks.MarkMemberActiveInDB(
                    inject={constants.MEMBER: m},
                    name='{flow}-{id}'.format(
                        id=m.id, flow=constants.MARK_MEMBER_ACTIVE_INDB)))

        # Update existing members
        unordered_members_flow.add(
            lifecycle_tasks.MembersToErrorOnRevertTask(
                # updated_members is a list of (obj, dict), only pass `obj`
                inject={constants.MEMBERS: [m[0] for m in updated_members]},
                name='{flow}-updated'.format(
                    flow=constants.MEMBER_TO_ERROR_ON_REVERT_FLOW)))
        for m, um in updated_members:
            um.pop('id', None)
            unordered_members_flow.add(
                model_tasks.UpdateAttributes(
                    inject={
                        constants.OBJECT: m,
                        constants.UPDATE_DICT: um
                    },
                    name='{flow}-{id}'.format(
                        id=m.id, flow=constants.UPDATE_ATTRIBUTES_FLOW)))
            unordered_members_flow.add(
                database_tasks.UpdateMemberInDB(
                    inject={
                        constants.MEMBER: m,
                        constants.UPDATE_DICT: um
                    },
                    name='{flow}-{id}'.format(
                        id=m.id, flow=constants.UPDATE_MEMBER_INDB)))
            unordered_members_active_flow.add(
                database_tasks.MarkMemberActiveInDB(
                    inject={constants.MEMBER: m},
                    name='{flow}-{id}'.format(
                        id=m.id, flow=constants.MARK_MEMBER_ACTIVE_INDB)))

        batch_update_members_flow.add(unordered_members_flow)

        # Done, do real updates
        batch_update_members_flow.add(
            network_tasks.CalculateDelta(requires=constants.LOADBALANCER,
                                         provides=constants.DELTAS))
        batch_update_members_flow.add(
            network_tasks.HandleNetworkDeltas(requires=constants.DELTAS,
                                              provides=constants.ADDED_PORTS))
        batch_update_members_flow.add(
            amphora_driver_tasks.AmphoraePostNetworkPlug(
                requires=(constants.LOADBALANCER, constants.ADDED_PORTS)))

        # Update the Listener (this makes the changes active on the Amp)
        batch_update_members_flow.add(
            amphora_driver_tasks.ListenersUpdate(
                requires=(constants.LOADBALANCER, constants.LISTENERS)))

        # Mark all the members ACTIVE here, then pool then LB/Listeners
        batch_update_members_flow.add(unordered_members_active_flow)
        batch_update_members_flow.add(
            database_tasks.MarkPoolActiveInDB(requires=constants.POOL))
        batch_update_members_flow.add(
            database_tasks.MarkLBAndListenersActiveInDB(
                requires=(constants.LOADBALANCER, constants.LISTENERS)))

        return batch_update_members_flow
Beispiel #6
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    def test_calculate_delta(self, mock_get_net_driver):
        mock_driver = mock.MagicMock()
        mock_get_net_driver.return_value = mock_driver
        EMPTY = {}
        empty_deltas = {
            self.amphora_mock.id:
            data_models.Delta(amphora_id=self.amphora_mock.id,
                              compute_id=self.amphora_mock.compute_id,
                              add_nics=[],
                              delete_nics=[])
        }

        calc_delta = network_tasks.CalculateDelta()

        self.assertEqual(EMPTY, calc_delta.execute(self.load_balancer_mock))

        # Test with one amp and no pools, nothing plugged
        # Delta should be empty
        mock_driver.reset_mock()

        self.amphora_mock.load_balancer = self.load_balancer_mock
        self.load_balancer_mock.amphorae = [self.amphora_mock]
        self.load_balancer_mock.pools = []

        self.assertEqual(empty_deltas,
                         calc_delta.execute(self.load_balancer_mock))
        mock_driver.get_plugged_networks.assert_called_once_with(COMPUTE_ID)

        # Pool mock should be configured explicitly for each test
        pool_mock = mock.MagicMock()
        self.load_balancer_mock.pools = [pool_mock]

        # Test with one amp and one pool but no members, nothing plugged
        # Delta should be empty
        pool_mock.members = []
        self.assertEqual(empty_deltas,
                         calc_delta.execute(self.load_balancer_mock))

        # Test with one amp and one pool and one member, nothing plugged
        # Delta should be one additional subnet to plug
        mock_driver.reset_mock()
        member_mock = mock.MagicMock()
        member_mock.subnet_id = 1
        pool_mock.members = [member_mock]
        mock_driver.get_subnet.return_value = data_models.Subnet(id=2,
                                                                 network_id=3)

        ndm = data_models.Delta(amphora_id=self.amphora_mock.id,
                                compute_id=self.amphora_mock.compute_id,
                                add_nics=[data_models.Interface(network_id=2)],
                                delete_nics=[])
        self.assertEqual({self.amphora_mock.id: ndm},
                         calc_delta.execute(self.load_balancer_mock))

        vrrp_port_call = mock.call(self.amphora_mock.vrrp_port_id)
        mock_driver.get_port.assert_has_calls([vrrp_port_call])
        self.assertEqual(1, mock_driver.get_port.call_count)

        member_subnet_call = mock.call(member_mock.subnet_id)
        mock_driver.get_subnet.assert_has_calls([member_subnet_call])
        self.assertEqual(1, mock_driver.get_subnet.call_count)

        # Test with one amp and one pool and one member, already plugged
        # Delta should be empty
        mock_driver.reset_mock()
        member_mock = mock.MagicMock()
        member_mock.subnet_id = 1
        pool_mock.members = [member_mock]
        mock_driver.get_plugged_networks.return_value = [
            data_models.Interface(network_id=2)
        ]

        self.assertEqual(empty_deltas,
                         calc_delta.execute(self.load_balancer_mock))

        # Test with one amp and one pool and one member, wrong network plugged
        # Delta should be one network to add and one to remove
        mock_driver.reset_mock()
        member_mock = mock.MagicMock()
        member_mock.subnet_id = 1
        pool_mock.members = [member_mock]
        mock_driver.get_plugged_networks.return_value = [
            data_models.Interface(network_id=3)
        ]

        ndm = data_models.Delta(
            amphora_id=self.amphora_mock.id,
            compute_id=self.amphora_mock.compute_id,
            add_nics=[data_models.Interface(network_id=2)],
            delete_nics=[data_models.Interface(network_id=3)])
        self.assertEqual({self.amphora_mock.id: ndm},
                         calc_delta.execute(self.load_balancer_mock))

        # Test with one amp and one pool and no members, one network plugged
        # Delta should be one network to remove
        mock_driver.reset_mock()
        pool_mock.members = []
        mock_driver.get_plugged_networks.return_value = [
            data_models.Interface(network_id=2)
        ]

        ndm = data_models.Delta(
            amphora_id=self.amphora_mock.id,
            compute_id=self.amphora_mock.compute_id,
            add_nics=[],
            delete_nics=[data_models.Interface(network_id=2)])
        self.assertEqual({self.amphora_mock.id: ndm},
                         calc_delta.execute(self.load_balancer_mock))
Beispiel #7
0
    def test_calculate_delta(self, mock_driver):
        EMPTY = {}
        empty_deltas = {
            self.amphora_mock.id:
            data_models.Delta(amphora_id=self.amphora_mock.id,
                              compute_id=self.amphora_mock.compute_id,
                              add_nics=[],
                              delete_nics=[])
        }

        def _interface(network_id):
            return [data_models.Interface(network_id=network_id)]

        net = network_tasks.CalculateDelta()

        self.assertEqual(EMPTY, net.execute(self.load_balancer_mock))

        self.amphora_mock.load_balancer = self.load_balancer_mock
        self.load_balancer_mock.amphorae = [self.amphora_mock]
        self.load_balancer_mock.listeners = None
        self.assertEqual({self.amphora_mock.id: None},
                         net.execute(self.load_balancer_mock))

        listener_mock = mock.MagicMock()
        self.load_balancer_mock.listeners = [listener_mock]
        listener_mock.default_pool = None
        self.assertEqual(empty_deltas, net.execute(self.load_balancer_mock))
        mock_driver.get_plugged_networks.assert_called_once_with(COMPUTE_ID)

        pool_mock = mock.MagicMock()
        listener_mock.default_pool = pool_mock
        pool_mock.members = None
        self.assertEqual(empty_deltas, net.execute(self.load_balancer_mock))

        member_mock = mock.MagicMock()
        pool_mock.members = [member_mock]
        member_mock.subnet_id = 1

        mock_driver.get_subnet.reset_mock()
        mock_driver.get_subnet.return_value = data_models.Subnet(id=2,
                                                                 network_id=3)

        ndm = data_models.Delta(amphora_id=self.amphora_mock.id,
                                compute_id=self.amphora_mock.compute_id,
                                add_nics=_interface(2),
                                delete_nics=[])
        self.assertEqual({self.amphora_mock.id: ndm},
                         net.execute(self.load_balancer_mock))

        vip_subnet_call = mock.call(self.vip_mock.subnet_id)
        member_subnet_call = mock.call(member_mock.subnet_id)
        mock_driver.get_subnet.assert_has_calls(
            [vip_subnet_call, member_subnet_call])
        self.assertEqual(2, mock_driver.get_subnet.call_count)

        mock_driver.get_plugged_networks.return_value = _interface(2)
        self.assertEqual(empty_deltas, net.execute(self.load_balancer_mock))

        mock_driver.get_plugged_networks.return_value = _interface(3)
        ndm = data_models.Delta(amphora_id=self.amphora_mock.id,
                                compute_id=self.amphora_mock.compute_id,
                                add_nics=_interface(2),
                                delete_nics=_interface(3))
        self.assertEqual({self.amphora_mock.id: ndm},
                         net.execute(self.load_balancer_mock))

        pool_mock.members = []
        mock_driver.get_plugged_networks.return_value = _interface(2)
        ndm = data_models.Delta(amphora_id=self.amphora_mock.id,
                                compute_id=self.amphora_mock.compute_id,
                                add_nics=[],
                                delete_nics=_interface(2))
        self.assertEqual({self.amphora_mock.id: ndm},
                         net.execute(self.load_balancer_mock))
Beispiel #8
0
    def get_failover_flow(self,
                          role=constants.ROLE_STANDALONE,
                          load_balancer_id=None):
        """Creates a flow to failover a stale amphora

        :returns: The flow for amphora failover
        """

        failover_amphora_flow = linear_flow.Flow(
            constants.FAILOVER_AMPHORA_FLOW)

        failover_amphora_flow.add(
            lifecycle_tasks.AmphoraToErrorOnRevertTask(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA))

        # Note: It seems intuitive to boot an amphora prior to deleting
        #       the old amphora, however this is a complicated issue.
        #       If the target host (due to anit-affinity) is resource
        #       constrained, this will fail where a post-delete will
        #       succeed. Since this is async with the API it would result
        #       in the LB ending in ERROR though the amps are still alive.
        #       Consider in the future making this a complicated
        #       try-on-failure-retry flow, or move upgrade failovers to be
        #       synchronous with the API. For now spares pool and act/stdby
        #       will mitigate most of this delay.

        # Delete the old amphora
        failover_amphora_flow.add(
            database_tasks.MarkAmphoraPendingDeleteInDB(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA))
        failover_amphora_flow.add(
            database_tasks.MarkAmphoraHealthBusy(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA))
        failover_amphora_flow.add(
            compute_tasks.ComputeDelete(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA))
        failover_amphora_flow.add(
            network_tasks.WaitForPortDetach(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA))
        failover_amphora_flow.add(
            database_tasks.MarkAmphoraDeletedInDB(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA))

        # If this is an unallocated amp (spares pool), we're done
        if not load_balancer_id:
            failover_amphora_flow.add(
                database_tasks.DisableAmphoraHealthMonitoring(
                    rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                    requires=constants.AMPHORA))
            return failover_amphora_flow

        # Save failed amphora details for later
        failover_amphora_flow.add(
            database_tasks.GetAmphoraDetails(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA,
                provides=constants.AMP_DATA))

        # Get a new amphora
        # Note: Role doesn't matter here.  We will update it later.
        get_amp_subflow = self.get_amphora_for_lb_subflow(
            prefix=constants.FAILOVER_AMPHORA_FLOW)
        failover_amphora_flow.add(get_amp_subflow)

        # Update the new amphora with the failed amphora details
        failover_amphora_flow.add(
            database_tasks.UpdateAmpFailoverDetails(
                requires=(constants.AMPHORA, constants.AMP_DATA)))

        # Update the data stored in the flow from the database
        failover_amphora_flow.add(
            database_tasks.ReloadLoadBalancer(
                requires=constants.LOADBALANCER_ID,
                provides=constants.LOADBALANCER))

        failover_amphora_flow.add(
            database_tasks.ReloadAmphora(requires=constants.AMPHORA_ID,
                                         provides=constants.AMPHORA))

        # Prepare to reconnect the network interface(s)
        failover_amphora_flow.add(
            network_tasks.GetAmphoraeNetworkConfigs(
                requires=constants.LOADBALANCER,
                provides=constants.AMPHORAE_NETWORK_CONFIG))
        failover_amphora_flow.add(
            database_tasks.GetListenersFromLoadbalancer(
                requires=constants.LOADBALANCER, provides=constants.LISTENERS))

        failover_amphora_flow.add(
            amphora_driver_tasks.ListenersUpdate(
                requires=(constants.LOADBALANCER, constants.LISTENERS)))

        # Plug the VIP ports into the new amphora
        failover_amphora_flow.add(
            network_tasks.PlugVIPPort(
                requires=(constants.AMPHORA,
                          constants.AMPHORAE_NETWORK_CONFIG)))
        failover_amphora_flow.add(
            amphora_driver_tasks.AmphoraPostVIPPlug(
                requires=(constants.AMPHORA, constants.LOADBALANCER,
                          constants.AMPHORAE_NETWORK_CONFIG)))

        # Plug the member networks into the new amphora
        failover_amphora_flow.add(
            network_tasks.CalculateDelta(requires=constants.LOADBALANCER,
                                         provides=constants.DELTAS))
        failover_amphora_flow.add(
            network_tasks.HandleNetworkDeltas(requires=constants.DELTAS,
                                              provides=constants.ADDED_PORTS))
        failover_amphora_flow.add(
            amphora_driver_tasks.AmphoraePostNetworkPlug(
                requires=(constants.LOADBALANCER, constants.ADDED_PORTS)))

        # Handle the amphora role and VRRP if necessary
        if role == constants.ROLE_MASTER:
            failover_amphora_flow.add(
                database_tasks.MarkAmphoraMasterInDB(
                    name=constants.MARK_AMP_MASTER_INDB,
                    requires=constants.AMPHORA))
            vrrp_subflow = self.get_vrrp_subflow(role)
            failover_amphora_flow.add(vrrp_subflow)
        elif role == constants.ROLE_BACKUP:
            failover_amphora_flow.add(
                database_tasks.MarkAmphoraBackupInDB(
                    name=constants.MARK_AMP_BACKUP_INDB,
                    requires=constants.AMPHORA))
            vrrp_subflow = self.get_vrrp_subflow(role)
            failover_amphora_flow.add(vrrp_subflow)
        elif role == constants.ROLE_STANDALONE:
            failover_amphora_flow.add(
                database_tasks.MarkAmphoraStandAloneInDB(
                    name=constants.MARK_AMP_STANDALONE_INDB,
                    requires=constants.AMPHORA))

        failover_amphora_flow.add(
            amphora_driver_tasks.ListenersStart(
                requires=(constants.LOADBALANCER, constants.LISTENERS)))
        failover_amphora_flow.add(
            database_tasks.DisableAmphoraHealthMonitoring(
                rebind={constants.AMPHORA: constants.FAILED_AMPHORA},
                requires=constants.AMPHORA))

        return failover_amphora_flow
    def test_calculate_delta(self, mock_get_net_driver):
        mock_driver = mock.MagicMock()
        mock_get_net_driver.return_value = mock_driver
        EMPTY = {}
        empty_deltas = {self.amphora_mock.id: data_models.Delta(
            amphora_id=self.amphora_mock.id,
            compute_id=self.amphora_mock.compute_id,
            add_nics=[],
            delete_nics=[])}

        def _interface(network_id):
            return [data_models.Interface(network_id=network_id)]

        net = network_tasks.CalculateDelta()

        self.assertEqual(EMPTY, net.execute(self.load_balancer_mock))

        self.amphora_mock.load_balancer = self.load_balancer_mock
        self.load_balancer_mock.amphorae = [self.amphora_mock]
        self.load_balancer_mock.pools = []

        self.assertEqual(empty_deltas, net.execute(self.load_balancer_mock))
        mock_driver.get_plugged_networks.assert_called_once_with(COMPUTE_ID)

        pool_mock = mock.MagicMock()
        self.load_balancer_mock.pools = [pool_mock]
        pool_mock.members = []
        self.assertEqual(empty_deltas, net.execute(self.load_balancer_mock))

        member_mock = mock.MagicMock()
        pool_mock.members = [member_mock]
        member_mock.subnet_id = 1

        mock_driver.get_subnet.reset_mock()
        mock_driver.get_subnet.return_value = data_models.Subnet(id=2,
                                                                 network_id=3)

        ndm = data_models.Delta(amphora_id=self.amphora_mock.id,
                                compute_id=self.amphora_mock.compute_id,
                                add_nics=_interface(2),
                                delete_nics=[])
        self.assertEqual({self.amphora_mock.id: ndm},
                         net.execute(self.load_balancer_mock))

        vrrp_port_call = mock.call(self.amphora_mock.vrrp_port_id)
        mock_driver.get_port.assert_has_calls([vrrp_port_call])
        # For some reason we call calculate_delta three times?
        self.assertEqual(3, mock_driver.get_port.call_count)

        member_subnet_call = mock.call(member_mock.subnet_id)
        mock_driver.get_subnet.assert_has_calls([member_subnet_call])
        self.assertEqual(1, mock_driver.get_subnet.call_count)

        mock_driver.get_plugged_networks.return_value = _interface(2)
        self.assertEqual(empty_deltas, net.execute(self.load_balancer_mock))

        mock_driver.get_plugged_networks.return_value = _interface(3)
        ndm = data_models.Delta(amphora_id=self.amphora_mock.id,
                                compute_id=self.amphora_mock.compute_id,
                                add_nics=_interface(2),
                                delete_nics=_interface(3))
        self.assertEqual({self.amphora_mock.id: ndm},
                         net.execute(self.load_balancer_mock))

        pool_mock.members = []
        mock_driver.get_plugged_networks.return_value = _interface(2)
        ndm = data_models.Delta(amphora_id=self.amphora_mock.id,
                                compute_id=self.amphora_mock.compute_id,
                                add_nics=[],
                                delete_nics=_interface(2))
        self.assertEqual({self.amphora_mock.id: ndm},
                         net.execute(self.load_balancer_mock))