Try with server streaming alone.

Author: kannanjgithub

interop-testing/src/main/java/io/grpc/testing/integration/TestCases.java

@@ -60,7 +60,8 @@ public enum TestCases {
   CHANNEL_SOAK("sends 'soak_iterations' large_unary rpcs in a loop, each on a new channel"),
   ORCA_PER_RPC("report backend metrics per query"),
   ORCA_OOB("report backend metrics out-of-band"),
-  MCS("max concurrent streaming");
+  MCS("max concurrent streaming"),
+  MCSSS("mcs server streaming");
 
   private final String description;
 

interop-testing/src/main/java/io/grpc/testing/integration/TestServiceClient.java

@@ -581,6 +581,11 @@ private void runTest(TestCases testCase) throws Exception {
         break;
       }
 
+      case MCSSS: {
+        tester.testMcs_serverStreaming();
+        break;
+      }
+
       default:
         throw new IllegalArgumentException("Unknown test case: " + testCase);
     }
@@ -1123,7 +1128,16 @@ public void testMcs() throws Exception {
 
       assertThat(fakeMetricsSink.openConnectionCount).isEqualTo(2);
     }
-  }
+
+    public void testMcs_serverStreaming() throws Exception {
+      StreamingOutputCallRequest request = StreamingOutputCallRequest.newBuilder()
+          .addResponseParameters(ResponseParameters.newBuilder().setSize(1).build()).build();
+      StreamingOutputCallResponseObserver responseObserver1 = new StreamingOutputCallResponseObserver();
+      asyncStub.streamingOutputCall(request, responseObserver1);
+      assertThat(responseObserver1.take()).isInstanceOf(StreamingOutputCallResponse.class);
+    }
+
+    }
 
   private static String validTestCasesHelpText() {
     StringBuilder builder = new StringBuilder();