1 files changed, 26 insertions, 26 deletions

diff --git a/test/proto/messages.proto b/test/proto/messages.proto
index 89e55443b5..193b6c4171 100644
--- a/test/proto/messages.proto
+++ b/test/proto/messages.proto
@@ -30,7 +30,7 @@
 
 // Message definitions to be used by integration test service definitions.
 
-syntax = "proto2";
+syntax = "proto3";
 
 package grpc.testing;
 
@@ -57,59 +57,59 @@ enum CompressionType {
 // A block of data, to simply increase gRPC message size.
 message Payload {
   // The type of data in body.
-  optional PayloadType type = 1;
+  PayloadType type = 1;
   // Primary contents of payload.
-  optional bytes body = 2;
+  bytes body = 2;
 }
 
 // A protobuf representation for grpc status. This is used by test
 // clients to specify a status that the server should attempt to return.
-message EchoStatus { 
-  optional int32 code = 1;
-  optional string message = 2;
+message EchoStatus {
+  int32 code = 1;
+  string message = 2;
 }
 
 // Unary request.
 message SimpleRequest {
   // Desired payload type in the response from the server.
   // If response_type is RANDOM, server randomly chooses one from other formats.
-  optional PayloadType response_type = 1;
+  PayloadType response_type = 1;
 
   // Desired payload size in the response from the server.
   // If response_type is COMPRESSABLE, this denotes the size before compression.
-  optional int32 response_size = 2;
+  int32 response_size = 2;
 
   // Optional input payload sent along with the request.
-  optional Payload payload = 3;
+  Payload payload = 3;
 
   // Whether SimpleResponse should include username.
-  optional bool fill_username = 4;
+  bool fill_username = 4;
 
   // Whether SimpleResponse should include OAuth scope.
-  optional bool fill_oauth_scope = 5;
+  bool fill_oauth_scope = 5;
 
   // Compression algorithm to be used by the server for the response (stream)
-  optional CompressionType response_compression = 6;
+  CompressionType response_compression = 6;
 
   // Whether server should return a given status
-  optional EchoStatus response_status = 7;
+  EchoStatus response_status = 7;
 }
 
 // Unary response, as configured by the request.
 message SimpleResponse {
   // Payload to increase message size.
-  optional Payload payload = 1;
+  Payload payload = 1;
   // The user the request came from, for verifying authentication was
   // successful when the client expected it.
-  optional string username = 2;
+  string username = 2;
   // OAuth scope.
-  optional string oauth_scope = 3;
+  string oauth_scope = 3;
 }
 
 // Client-streaming request.
 message StreamingInputCallRequest {
   // Optional input payload sent along with the request.
-  optional Payload payload = 1;
+  Payload payload = 1;
 
   // Not expecting any payload from the response.
 }
@@ -117,18 +117,18 @@ message StreamingInputCallRequest {
 // Client-streaming response.
 message StreamingInputCallResponse {
   // Aggregated size of payloads received from the client.
-  optional int32 aggregated_payload_size = 1;
+  int32 aggregated_payload_size = 1;
 }
 
 // Configuration for a particular response.
 message ResponseParameters {
   // Desired payload sizes in responses from the server.
   // If response_type is COMPRESSABLE, this denotes the size before compression.
-  optional int32 size = 1;
+  int32 size = 1;
 
   // Desired interval between consecutive responses in the response stream in
   // microseconds.
-  optional int32 interval_us = 2;
+  int32 interval_us = 2;
 }
 
 // Server-streaming request.
@@ -137,31 +137,31 @@ message StreamingOutputCallRequest {
   // If response_type is RANDOM, the payload from each response in the stream
   // might be of different types. This is to simulate a mixed type of payload
   // stream.
-  optional PayloadType response_type = 1;
+  PayloadType response_type = 1;
 
   // Configuration for each expected response message.
   repeated ResponseParameters response_parameters = 2;
 
   // Optional input payload sent along with the request.
-  optional Payload payload = 3;
+  Payload payload = 3;
 
   // Compression algorithm to be used by the server for the response (stream)
-  optional CompressionType response_compression = 6;
+  CompressionType response_compression = 6;
 
   // Whether server should return a given status
-  optional EchoStatus response_status = 7;
+  EchoStatus response_status = 7;
 }
 
 // Server-streaming response, as configured by the request and parameters.
 message StreamingOutputCallResponse {
   // Payload to increase response size.
-  optional Payload payload = 1;
+  Payload payload = 1;
 }
 
 // For reconnect interop test only.
 // Server tells client whether its reconnects are following the spec and the
 // reconnect backoffs it saw.
 message ReconnectInfo {
-  optional bool passed = 1;
+  bool passed = 1;
   repeated int32 backoff_ms = 2;
 }