def _validate(
        self,
        cv: ClusterView,
        ncs: List[NodeConfig],
        nss: List[NodeState],
        mnts: Tuple[MaintenanceDefinition, ...],
    ) -> None:
        nis = sorted(nc.node_index for nc in ncs)
        ni_to_nc = {nc.node_index: nc for nc in ncs}
        ni_to_ns = {ns.node_index: ns for ns in nss}
        ni_to_mnts: Dict[int,
                         List[MaintenanceDefinition]] = {ni: []
                                                         for ni in nis}
        for mnt in mnts:
            mnt_nis = set()
            for s in mnt.shards:
                assert s.node.node_index is not None
                mnt_nis.add(s.node.node_index)
            for n in mnt.sequencer_nodes:
                assert n.node_index is not None
                mnt_nis.add(n.node_index)
            for ni in mnt_nis:
                ni_to_mnts[ni].append(mnt)

        self.assertEqual(sorted(cv.get_all_node_indexes()),
                         sorted(ni_to_nc.keys()))

        self.assertEqual(
            sorted(cv.get_all_node_views(),
                   key=operator.attrgetter("node_index")),
            sorted(
                (NodeView(
                    node_config=ni_to_nc[ni],
                    node_state=ni_to_ns[ni],
                    maintenances=tuple(ni_to_mnts[ni]),
                ) for ni in ni_to_nc.keys()),
                key=operator.attrgetter("node_index"),
            ),
        )

        self.assertEqual(sorted(cv.get_all_node_names()),
                         sorted(nc.name for nc in ncs))

        self.assertEqual(
            sorted(cv.get_all_maintenance_ids()),
            # pyre-fixme[6]: Expected `Iterable[Variable[_LT (bound to
            #  _SupportsLessThan)]]` for 1st param but got
            #  `Generator[typing.Optional[str], None, None]`.
            sorted(mnt.group_id for mnt in mnts),
        )

        self.assertEqual(
            sorted(cv.get_all_maintenances(),
                   key=operator.attrgetter("group_id")),
            sorted(mnts, key=operator.attrgetter("group_id")),
        )

        for ni in nis:
            nn = ni_to_nc[ni].name
            nc = ni_to_nc[ni]
            ns = ni_to_ns[ni]
            node_mnts = tuple(ni_to_mnts[ni])
            nv = NodeView(
                node_config=ni_to_nc[ni],
                node_state=ni_to_ns[ni],
                maintenances=node_mnts,
            )

            self.assertEqual(cv.get_node_view_by_node_index(ni), nv)
            self.assertEqual(cv.get_node_name_by_node_index(ni), nn)
            self.assertEqual(cv.get_node_config_by_node_index(ni), nc)
            self.assertEqual(cv.get_node_state_by_node_index(ni), ns)
            self.assertEqual(cv.get_node_maintenances_by_node_index(ni),
                             node_mnts)

            self.assertEqual(cv.get_node_view_by_node_name(nn), nv)
            self.assertEqual(cv.get_node_index_by_node_name(nn), ni)
            self.assertEqual(cv.get_node_config_by_node_name(nn), nc)
            self.assertEqual(cv.get_node_state_by_node_name(nn), ns)
            self.assertEqual(cv.get_node_maintenances_by_node_name(nn),
                             node_mnts)

            self.assertEqual(cv.get_node_view(node_name=nn), nv)
            self.assertEqual(cv.get_node_index(node_name=nn), ni)
            self.assertEqual(cv.get_node_config(node_name=nn), nc)
            self.assertEqual(cv.get_node_state(node_name=nn), ns)
            self.assertEqual(cv.get_node_maintenances(node_name=nn), node_mnts)

            self.assertEqual(cv.get_node_view(node_index=ni), nv)
            self.assertEqual(cv.get_node_name(node_index=ni), nn)
            self.assertEqual(cv.get_node_config(node_index=ni), nc)
            self.assertEqual(cv.get_node_state(node_index=ni), ns)
            self.assertEqual(cv.get_node_maintenances(node_index=ni),
                             node_mnts)

        with self.assertRaises(ValueError):
            cv.get_node_view(None, None)

        with self.assertRaises(ValueError):
            cv.get_node_config(None, None)

        with self.assertRaises(ValueError):
            cv.get_node_state(None, None)

        with self.assertRaises(ValueError):
            cv.get_node_maintenances(None, None)

        # mismatch node_index and node_name
        if len(nis) > 1:
            nn = ni_to_nc[nis[0]].name
            ni = nis[1]
            with self.assertRaises(ValueError):
                cv.get_node_view(ni, nn)

            with self.assertRaises(ValueError):
                cv.get_node_config(ni, nn)

            with self.assertRaises(ValueError):
                cv.get_node_state(ni, nn)

            with self.assertRaises(ValueError):
                cv.get_node_maintenances(ni, nn)

        # non-existent node_index
        with self.assertRaises(NodeNotFoundError):
            cv.get_node_view(node_index=max(nis) + 1)

        # non-existent node_name
        with self.assertRaises(NodeNotFoundError):
            nns = {nc.name for nc in ncs}
            nn: str = ""
            while True:
                nn = gen_word()
                if nn not in nns:
                    break
            cv.get_node_view(node_name=nn)

        for mnt in mnts:
            group_id: str = mnt.group_id or ""
            self.assertEqual(cv.get_maintenance_by_id(group_id), mnt)
            self.assertTupleEqual(
                cv.get_node_indexes_by_maintenance_id(group_id),
                tuple(
                    sorted(
                        set({
                            n.node_index
                            for n in mnt.sequencer_nodes
                            if n.node_index is not None
                        }).union({
                            s.node.node_index
                            for s in mnt.shards
                            if s.node.node_index is not None
                        }))),
            )
            self.assertEqual(group_id,
                             cv.get_maintenance_view_by_id(group_id).group_id)

        self.assertListEqual(
            # pyre-fixme[6]: Expected `Iterable[Variable[_LT (bound to
            #  _SupportsLessThan)]]` for 1st param but got
            #  `Generator[typing.Optional[str], None, None]`.
            sorted(m.group_id for m in mnts),
            sorted(mv.group_id for mv in cv.get_all_maintenance_views()),
        )

        # expand_shards
        self.assertEqual(
            cv.expand_shards(shards=[
                ShardID(node=NodeID(node_index=nis[0]), shard_index=0)
            ]),
            (ShardID(
                node=NodeID(
                    node_index=ni_to_nc[nis[0]].node_index,
                    name=ni_to_nc[nis[0]].name,
                    address=ni_to_nc[nis[0]].data_address,
                ),
                shard_index=0,
            ), ),
        )
        num_shards: int = getattr(ni_to_nc[nis[0]], "storage",
                                  StorageConfig()).num_shards
        self.assertEqual(
            len(
                cv.expand_shards(shards=[
                    ShardID(node=NodeID(node_index=nis[0]),
                            shard_index=ALL_SHARDS)
                ])),
            num_shards,
        )
        self.assertEqual(
            len(
                cv.expand_shards(shards=[
                    ShardID(node=NodeID(node_index=nis[0]),
                            shard_index=ALL_SHARDS),
                    ShardID(node=NodeID(node_index=nis[0]),
                            shard_index=ALL_SHARDS),
                    ShardID(node=NodeID(node_index=nis[1]),
                            shard_index=ALL_SHARDS),
                ])),
            getattr(ni_to_nc[nis[0]], "storage", StorageConfig()).num_shards +
            getattr(ni_to_nc[nis[1]], "storage", StorageConfig()).num_shards,
        )
        self.assertEqual(
            len(
                cv.expand_shards(
                    shards=[
                        ShardID(node=NodeID(node_index=nis[0]),
                                shard_index=ALL_SHARDS),
                        ShardID(node=NodeID(node_index=nis[1]), shard_index=0),
                    ],
                    node_ids=[NodeID(node_index=0)],
                )),
            getattr(ni_to_nc[nis[0]], "storage", StorageConfig()).num_shards +
            1,
        )

        # normalize_node_id
        self.assertEqual(
            cv.normalize_node_id(NodeID(node_index=nis[0])),
            NodeID(
                node_index=nis[0],
                address=ni_to_nc[nis[0]].data_address,
                name=ni_to_nc[nis[0]].name,
            ),
        )
        self.assertEqual(
            cv.normalize_node_id(NodeID(name=ni_to_nc[nis[0]].name)),
            NodeID(
                node_index=nis[0],
                address=ni_to_nc[nis[0]].data_address,
                name=ni_to_nc[nis[0]].name,
            ),
        )

        # get_node_id
        self.assertEqual(cv.get_node_id(node_index=0).node_index, 0)

        # search_maintenances
        storages_node_views = [
            nv for nv in cv.get_all_node_views() if nv.is_storage
        ]
        sequencers_node_views = [
            nv for nv in cv.get_all_node_views() if nv.is_sequencer
        ]
        self.assertEqual(len(cv.search_maintenances()), len(mnts))
        self.assertEqual(len(cv.search_maintenances(node_ids=[])), 0)
        self.assertEqual(
            len(
                cv.search_maintenances(sequencer_nodes=[
                    storages_node_views[3].node_id,
                    sequencers_node_views[4].node_id,
                ])),
            1,
        )
        self.assertEqual(
            len(
                cv.search_maintenances(node_ids=[
                    storages_node_views[3].node_id,
                    sequencers_node_views[4].node_id,
                ])),
            1,
        )
        self.assertEqual(
            len(
                cv.search_maintenances(shards=[
                    ShardID(node=storages_node_views[1].node_id, shard_index=1)
                ])),
            1,
        )

        # shard_target_state
        self.assertEqual(
            len(
                cv.search_maintenances(
                    shard_target_state=ShardOperationalState.MAY_DISAPPEAR)),
            3,
        )
        self.assertEqual(
            len(
                cv.search_maintenances(
                    shard_target_state=ShardOperationalState.DRAINED)),
            0,
        )

        # sequencer_target_state
        self.assertEqual(
            len(
                cv.search_maintenances(
                    sequencer_target_state=SequencingState.ENABLED)),
            0,
        )
        self.assertEqual(
            len(
                cv.search_maintenances(
                    sequencer_target_state=SequencingState.DISABLED)),
            3,
        )

        self.assertEqual(len(cv.search_maintenances(user="******")), 1)
        self.assertEqual(len(cv.search_maintenances(reason="whatever")), 1)

        self.assertEqual(len(cv.search_maintenances(skip_safety_checks=True)),
                         0)
        self.assertEqual(len(cv.search_maintenances(skip_safety_checks=False)),
                         4)

        self.assertEqual(
            len(cv.search_maintenances(force_restore_rebuilding=True)), 0)
        self.assertEqual(
            len(cv.search_maintenances(force_restore_rebuilding=False)), 4)

        self.assertEqual(
            len(cv.search_maintenances(allow_passive_drains=True)), 0)
        self.assertEqual(
            len(cv.search_maintenances(allow_passive_drains=False)), 4)

        self.assertEqual(
            len(cv.search_maintenances(group_id=mnts[0].group_id)), 1)

        self.assertEqual(
            len(
                cv.search_maintenances(
                    progress=MaintenanceProgress.IN_PROGRESS)), 4)
    def _validate(
        self,
        cv: ClusterView,
        ncs: List[NodeConfig],
        nss: List[NodeState],
        mnts: Tuple[MaintenanceDefinition, ...],
    ):
        nis = sorted(nc.node_index for nc in ncs)
        ni_to_nc = {nc.node_index: nc for nc in ncs}
        ni_to_ns = {ns.node_index: ns for ns in nss}
        ni_to_mnts: Dict[int,
                         List[MaintenanceDefinition]] = {ni: []
                                                         for ni in nis}
        for mnt in mnts:
            mnt_nis = set()
            for s in mnt.shards:
                assert s.node.node_index is not None
                mnt_nis.add(s.node.node_index)
            for n in mnt.sequencer_nodes:
                assert n.node_index is not None
                mnt_nis.add(n.node_index)
            for ni in mnt_nis:
                ni_to_mnts[ni].append(mnt)

        self.assertEqual(sorted(cv.get_all_node_indexes()),
                         sorted(ni_to_nc.keys()))

        self.assertEqual(
            sorted(cv.get_all_node_views(),
                   key=operator.attrgetter("node_index")),
            sorted(
                (NodeView(
                    node_config=ni_to_nc[ni],
                    node_state=ni_to_ns[ni],
                    maintenances=tuple(ni_to_mnts[ni]),
                ) for ni in ni_to_nc.keys()),
                key=operator.attrgetter("node_index"),
            ),
        )

        self.assertEqual(sorted(cv.get_all_node_names()),
                         sorted(nc.name for nc in ncs))

        self.assertEqual(sorted(cv.get_all_maintenance_ids()),
                         sorted(mnt.group_id for mnt in mnts))

        self.assertEqual(
            sorted(cv.get_all_maintenances(),
                   key=operator.attrgetter("group_id")),
            sorted(mnts, key=operator.attrgetter("group_id")),
        )

        for ni in nis:
            nn = ni_to_nc[ni].name
            nc = ni_to_nc[ni]
            ns = ni_to_ns[ni]
            node_mnts = tuple(ni_to_mnts[ni])
            nv = NodeView(
                node_config=ni_to_nc[ni],
                node_state=ni_to_ns[ni],
                maintenances=node_mnts,
            )

            self.assertEqual(cv.get_node_view_by_node_index(ni), nv)
            self.assertEqual(cv.get_node_name_by_node_index(ni), nn)
            self.assertEqual(cv.get_node_config_by_node_index(ni), nc)
            self.assertEqual(cv.get_node_state_by_node_index(ni), ns)
            self.assertEqual(cv.get_node_maintenances_by_node_index(ni),
                             node_mnts)

            self.assertEqual(cv.get_node_view_by_node_name(nn), nv)
            self.assertEqual(cv.get_node_index_by_node_name(nn), ni)
            self.assertEqual(cv.get_node_config_by_node_name(nn), nc)
            self.assertEqual(cv.get_node_state_by_node_name(nn), ns)
            self.assertEqual(cv.get_node_maintenances_by_node_name(nn),
                             node_mnts)

            self.assertEqual(cv.get_node_view(node_name=nn), nv)
            self.assertEqual(cv.get_node_index(node_name=nn), ni)
            self.assertEqual(cv.get_node_config(node_name=nn), nc)
            self.assertEqual(cv.get_node_state(node_name=nn), ns)
            self.assertEqual(cv.get_node_maintenances(node_name=nn), node_mnts)

            self.assertEqual(cv.get_node_view(node_index=ni), nv)
            self.assertEqual(cv.get_node_name(node_index=ni), nn)
            self.assertEqual(cv.get_node_config(node_index=ni), nc)
            self.assertEqual(cv.get_node_state(node_index=ni), ns)
            self.assertEqual(cv.get_node_maintenances(node_index=ni),
                             node_mnts)

        with self.assertRaises(ValueError):
            cv.get_node_view(None, None)

        with self.assertRaises(ValueError):
            cv.get_node_config(None, None)

        with self.assertRaises(ValueError):
            cv.get_node_state(None, None)

        with self.assertRaises(ValueError):
            cv.get_node_maintenances(None, None)

        # mismatch node_index and node_name
        if len(nis) > 1:
            nn = ni_to_nc[nis[0]].name
            ni = nis[1]
            with self.assertRaises(ValueError):
                cv.get_node_view(ni, nn)

            with self.assertRaises(ValueError):
                cv.get_node_config(ni, nn)

            with self.assertRaises(ValueError):
                cv.get_node_state(ni, nn)

            with self.assertRaises(ValueError):
                cv.get_node_maintenances(ni, nn)

        # non-existent node_index
        with self.assertRaises(NodeNotFoundError):
            cv.get_node_view(node_index=max(nis) + 1)

        # non-existent node_name
        with self.assertRaises(NodeNotFoundError):
            nns = {nc.name for nc in ncs}
            while True:
                nn = gen_word()
                if nn not in nns:
                    break
            cv.get_node_view(node_name=nn)

        for mnt in mnts:
            assert mnt.group_id is not None
            self.assertEqual(cv.get_maintenance_by_id(mnt.group_id), mnt)
            self.assertTupleEqual(
                cv.get_node_indexes_by_maintenance_id(mnt.group_id),
                tuple(
                    sorted(
                        set({
                            n.node_index
                            for n in mnt.sequencer_nodes
                            if n.node_index is not None
                        }).union({
                            s.node.node_index
                            for s in mnt.shards
                            if s.node.node_index is not None
                        }))),
            )
            self.assertEqual(
                mnt.group_id,
                cv.get_maintenance_view_by_id(mnt.group_id).group_id)

        self.assertListEqual(
            list(sorted(m.group_id for m in mnts)),
            list(sorted(mv.group_id for mv in cv.get_all_maintenance_views())),
        )