5 files changed, 18 insertions, 21 deletions
diff --git a/test/cpp/interop/interop_client.cc b/test/cpp/interop/interop_client.cc
index bc5b7adb1c..cb6a607167 100644
--- a/test/cpp/interop/interop_client.cc
+++ b/test/cpp/interop/interop_client.cc
@@ -445,7 +445,6 @@ void InteropClient::DoHalfDuplex() {
   unsigned int i = 0;
   StreamingOutputCallResponse response;
   while (stream->Read(&response)) {
-    GPR_ASSERT(response.payload().has_body());
     GPR_ASSERT(response.payload().body() ==
                grpc::string(response_stream_sizes[i], '\0'));
     ++i;
@@ -475,7 +474,6 @@ void InteropClient::DoPingPong() {
     payload->set_body(grpc::string(request_stream_sizes[i], '\0'));
     GPR_ASSERT(stream->Write(request));
     GPR_ASSERT(stream->Read(&response));
-    GPR_ASSERT(response.payload().has_body());
     GPR_ASSERT(response.payload().body() ==
                grpc::string(response_stream_sizes[i], '\0'));
   }
@@ -522,7 +520,6 @@ void InteropClient::DoCancelAfterFirstResponse() {
   StreamingOutputCallResponse response;
   GPR_ASSERT(stream->Write(request));
   GPR_ASSERT(stream->Read(&response));
-  GPR_ASSERT(response.payload().has_body());
   GPR_ASSERT(response.payload().body() == grpc::string(31415, '\0'));
   gpr_log(GPR_INFO, "Trying to cancel...");
   context.TryCancel();
diff --git a/test/cpp/interop/server.cc b/test/cpp/interop/server.cc
index 2ea8794e5a..319e394399 100644
--- a/test/cpp/interop/server.cc
+++ b/test/cpp/interop/server.cc
@@ -184,7 +184,7 @@ class TestServiceImpl : public TestService::Service {
     StreamingInputCallRequest request;
     int aggregated_payload_size = 0;
     while (reader->Read(&request)) {
-      if (request.has_payload() && request.payload().has_body()) {
+      if (request.has_payload()) {
         aggregated_payload_size += request.payload().body().size();
       }
     }
diff --git a/test/cpp/util/echo.proto b/test/cpp/util/echo.proto
index 58ec680ecd..6bb09316b4 100644
--- a/test/cpp/util/echo.proto
+++ b/test/cpp/util/echo.proto
@@ -28,7 +28,7 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-syntax = "proto2";
+syntax = "proto3";
 
 import "test/cpp/util/messages.proto";
 
diff --git a/test/cpp/util/echo_duplicate.proto b/test/cpp/util/echo_duplicate.proto
index e54c016d2f..9c1d67825a 100644
--- a/test/cpp/util/echo_duplicate.proto
+++ b/test/cpp/util/echo_duplicate.proto
@@ -30,7 +30,7 @@
 
 // This is a partial copy of echo.proto with a different package name.
 
-syntax = "proto2";
+syntax = "proto3";
 
 import "test/cpp/util/messages.proto";
 
diff --git a/test/cpp/util/messages.proto b/test/cpp/util/messages.proto
index 24e199b809..359d1db74f 100644
--- a/test/cpp/util/messages.proto
+++ b/test/cpp/util/messages.proto
@@ -28,32 +28,32 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-syntax = "proto2";
+syntax = "proto3";
 
 package grpc.cpp.test.util;
 
 message RequestParams {
-  optional bool echo_deadline = 1;
-  optional int32 client_cancel_after_us = 2;
-  optional int32 server_cancel_after_us = 3;
-  optional bool echo_metadata = 4;
-  optional bool check_auth_context = 5;
-  optional int32 response_message_length = 6;
-  optional bool echo_peer = 7;
+  bool echo_deadline = 1;
+  int32 client_cancel_after_us = 2;
+  int32 server_cancel_after_us = 3;
+  bool echo_metadata = 4;
+  bool check_auth_context = 5;
+  int32 response_message_length = 6;
+  bool echo_peer = 7;
 }
 
 message EchoRequest {
-  optional string message = 1;
-  optional RequestParams param = 2;
+  string message = 1;
+  RequestParams param = 2;
 }
 
 message ResponseParams {
-  optional int64 request_deadline = 1;
-  optional string host = 2;
-  optional string peer = 3;
+  int64 request_deadline = 1;
+  string host = 2;
+  string peer = 3;
 }
 
 message EchoResponse {
-  optional string message = 1;
-  optional ResponseParams param = 2;
+  string message = 1;
+  ResponseParams param = 2;
 }