Add singleSignatureScheme feature flag toggle test

Author: WildFireFlum

bftengine/src/bftengine/TimeServiceManager.hpp

@@ -48,7 +48,7 @@ class TimeServiceManager {
   }
 
   // Used on recovery to restore the time prior the request that is about to be re-executed.
-  // In order to suport a correct behaviour of the compareAndUpdate method.
+  // In order to support a correct behaviour of the compareAndUpdate method.
   void recoverTime(const ConsensusTickRep& recovered_time) {
     auto last_timestamp = client_.getLastTimestamp().count();
     ConcordAssertLE(recovered_time, last_timestamp);

tests/apollo/test_skvbc_reconfiguration.py

@@ -20,9 +20,10 @@
 import difflib
 import random
 
+from util.consts import CHECKPOINT_SEQUENCES
 from util.test_base import ApolloTest, parameterize
 from util import skvbc as kvbc
-from util.bft import with_trio, with_bft_network, KEY_FILE_PREFIX, TestConfig
+from util.bft import with_trio, with_bft_network, KEY_FILE_PREFIX, TestConfig, ConsensusPathType
 from util import operator
 from util.object_store import ObjectStore, start_replica_cmd_prefix
 import sys
@@ -657,6 +658,40 @@ async def test_key_exchange_no_single_signature_scheme(self, bft_network):
         """
         await self._test_key_exchange(bft_network)
 
+    @with_trio
+    @with_bft_network(start_replica_cmd=\
+        lambda builddir, replica_id: start_replica_cmd(builddir, replica_id) +
+                                     ["--key-exchange-on-start", "True"] + ['--no-single-signature-scheme'],
+        selected_configs=lambda n, f, c: n == 7, publish_master_keys=True)
+    async def test_single_signature_scheme_to_no_single_signature_scheme(self, bft_network):
+        """
+        Ensure that the network can
+        """
+        bft_network.start_all_replicas()
+        skvbc = kvbc.SimpleKVBCProtocol(bft_network)
+        sequences_to_use_new_key = (CHECKPOINT_SEQUENCES * 3) + 1
+        await skvbc.send_n_kvs_sequentially(sequences_to_use_new_key, description='Make progress including initial consensus key exchange')
+
+        skvbc = kvbc.SimpleKVBCProtocol(bft_network)
+        client = bft_network.random_client()
+        op = operator.Operator(bft_network.config, client,  bft_network.builddir)
+        await op.add_remove_with_wedge('new_configuration_n_7_f_2_c_0', bft=False, restart=False)
+        await self.validate_stop_on_wedge_point(bft_network, skvbc, fullWedge=True)
+        conf = TestConfig(n=7, f=2, c=0, num_clients=10,
+                          key_file_prefix=KEY_FILE_PREFIX,
+                          start_replica_cmd=lambda builddir, replica_id: start_replica_cmd(builddir, replica_id) +
+                                                                         ["--key-exchange-on-start", "True"],
+                          stop_replica_cmd=None, num_ro_replicas=0)
+        await bft_network.change_configuration(conf, generate_tls=False)
+
+        bft_network.restart_clients(restart_replicas=True)
+        await self.validate_epoch_number(bft_network, epoch_number=1, replica_ids=bft_network.all_replicas())
+        await bft_network.wait_for_consensus_path(
+            path_type=ConsensusPathType.OPTIMISTIC_FAST, run_ops=
+            lambda: skvbc.send_n_kvs_sequentially(sequences_to_use_new_key,
+                                                  description='Progress after restarting with different main and consensus keys'),
+            threshold=sequences_to_use_new_key)
+
     @with_trio
     @with_bft_network(start_replica_cmd=start_replica_cmd_with_key_exchange, 
                       selected_configs=lambda n, f, c: n == 7,