test(emqx_bridge_kafka_impl_consumer_SUITE): fix flaky

apps/emqx_bridge_kafka/test/emqx_bridge_kafka_impl_consumer_SUITE.erl

@@ -698,6 +698,20 @@ create_bridge(Config, Overrides) ->
     KafkaConfig = emqx_utils_maps:deep_merge(KafkaConfig0, Overrides),
     emqx_bridge:create(Type, Name, KafkaConfig).
 
+create_bridge_wait_for_balance(Config) ->
+    setup_group_subscriber_spy(self()),
+    try
+        Res = create_bridge(Config),
+        receive
+            {kafka_assignment, _, _} ->
+                Res
+        after 20_000 ->
+            ct:fail("timed out waiting for kafka assignment")
+        end
+    after
+        kill_group_subscriber_spy()
+    end.
+
 delete_bridge(Config) ->
     Type = ?BRIDGE_TYPE_BIN,
     Name = ?config(kafka_name, Config),
@@ -1020,31 +1034,37 @@ reconstruct_assignments_from_events(KafkaTopic, Events0, Acc0) ->
 setup_group_subscriber_spy_fn() ->
     TestPid = self(),
     fun() ->
-        ok = meck:new(brod_group_subscriber_v2, [
+        setup_group_subscriber_spy(TestPid)
-            passthrough, no_link, no_history, non_strict
-        ]),
-        ok = meck:expect(
-            brod_group_subscriber_v2,
-            assignments_received,
-            fun(Pid, MemberId, GenerationId, TopicAssignments) ->
-                ?tp(
-                    kafka_assignment,
-                    #{
-                        node => node(),
-                        pid => Pid,
-                        member_id => MemberId,
-                        generation_id => GenerationId,
-                        topic_assignments => TopicAssignments
-                    }
-                ),
-                TestPid !
-                    {kafka_assignment, node(), {Pid, MemberId, GenerationId, TopicAssignments}},
-                meck:passthrough([Pid, MemberId, GenerationId, TopicAssignments])
-            end
-        ),
-        ok
     end.
 
+setup_group_subscriber_spy(TestPid) ->
+    ok = meck:new(brod_group_subscriber_v2, [
+        passthrough, no_link, no_history, non_strict
+    ]),
+    ok = meck:expect(
+        brod_group_subscriber_v2,
+        assignments_received,
+        fun(Pid, MemberId, GenerationId, TopicAssignments) ->
+            ?tp(
+                kafka_assignment,
+                #{
+                    node => node(),
+                    pid => Pid,
+                    member_id => MemberId,
+                    generation_id => GenerationId,
+                    topic_assignments => TopicAssignments
+                }
+            ),
+            TestPid !
+                {kafka_assignment, node(), {Pid, MemberId, GenerationId, TopicAssignments}},
+            meck:passthrough([Pid, MemberId, GenerationId, TopicAssignments])
+        end
+    ),
+    ok.
+
+kill_group_subscriber_spy() ->
+    meck:unload(brod_group_subscriber_v2).
+
 wait_for_cluster_rpc(Node) ->
     %% need to wait until the config handler is ready after
     %% restarting during the cluster join.
@@ -1702,10 +1722,7 @@ t_dynamic_mqtt_topic(Config) ->
     MQTTTopic = emqx_topic:join([KafkaTopic, '#']),
     ?check_trace(
         begin
-            ?assertMatch(
+            ?assertMatch({ok, _}, create_bridge_wait_for_balance(Config)),
-                {ok, _},
-                create_bridge(Config)
-            ),
             wait_until_subscribers_are_ready(NPartitions, 40_000),
             {ok, C} = emqtt:start_link(),
             on_exit(fun() -> emqtt:stop(C) end),