|  | // Licensed to the Apache Software Foundation (ASF) under one | 
|  | // or more contributor license agreements.  See the NOTICE file | 
|  | // distributed with this work for additional information | 
|  | // regarding copyright ownership.  The ASF licenses this file | 
|  | // to you under the Apache License, Version 2.0 (the | 
|  | // "License"); you may not use this file except in compliance | 
|  | // with the License.  You may obtain a copy of the License at | 
|  | // | 
|  | //   http://www.apache.org/licenses/LICENSE-2.0 | 
|  | // | 
|  | // Unless required by applicable law or agreed to in writing, | 
|  | // software distributed under the License is distributed on an | 
|  | // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY | 
|  | // KIND, either express or implied.  See the License for the | 
|  | // specific language governing permissions and limitations | 
|  | // under the License. | 
|  |  | 
|  | syntax="proto2"; | 
|  | package example; | 
|  |  | 
|  | option cc_generic_services = true; | 
|  |  | 
|  | message EchoRequest { | 
|  | required int32 value = 1; | 
|  | }; | 
|  |  | 
|  | message EchoResponse { | 
|  | required int32 value = 1; | 
|  | }; | 
|  |  | 
|  | service EchoService { | 
|  | rpc Echo(EchoRequest) returns (EchoResponse); | 
|  | }; |