chore: import upstream snapshot with attribution

example/streaming_echo_c++/server.cpp

@@ -0,0 +1,113 @@
+// 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.
+
+// A server to receive EchoRequest and send back EchoResponse.
+
+#include <gflags/gflags.h>
+#include <butil/logging.h>
+#include <brpc/server.h>
+#include "echo.pb.h"
+#include <brpc/stream.h>
+
+DEFINE_bool(send_attachment, true, "Carry attachment along with response");
+DEFINE_int32(port, 8001, "TCP Port of this server");
+DEFINE_int32(idle_timeout_s, -1, "Connection will be closed if there is no "
+             "read/write operations during the last `idle_timeout_s'");
+
+class StreamReceiver : public brpc::StreamInputHandler {
+public:
+    virtual int on_received_messages(brpc::StreamId id, 
+                                     butil::IOBuf *const messages[], 
+                                     size_t size) {
+        std::ostringstream os;
+        for (size_t i = 0; i < size; ++i) {
+            os << "msg[" << i << "]=" << *messages[i];
+        }
+        LOG(INFO) << "Received from Stream=" << id << ": " << os.str();
+        return 0;
+    }
+    virtual void on_idle_timeout(brpc::StreamId id) {
+        LOG(INFO) << "Stream=" << id << " has no data transmission for a while";
+    }
+    virtual void on_closed(brpc::StreamId id) {
+        LOG(INFO) << "Stream=" << id << " is closed";
+    }
+
+};
+
+// Your implementation of example::EchoService
+class StreamingEchoService : public example::EchoService {
+public:
+    StreamingEchoService() : _sd(brpc::INVALID_STREAM_ID) {}
+    virtual ~StreamingEchoService() {
+        brpc::StreamClose(_sd);
+    };
+    virtual void Echo(google::protobuf::RpcController* controller,
+                      const example::EchoRequest* /*request*/,
+                      example::EchoResponse* response,
+                      google::protobuf::Closure* done) {
+        // This object helps you to call done->Run() in RAII style. If you need
+        // to process the request asynchronously, pass done_guard.release().
+        brpc::ClosureGuard done_guard(done);
+
+        brpc::Controller* cntl =
+            static_cast<brpc::Controller*>(controller);
+        brpc::StreamOptions stream_options;
+        stream_options.handler = &_receiver;
+        if (brpc::StreamAccept(&_sd, *cntl, &stream_options) != 0) {
+            cntl->SetFailed("Fail to accept stream");
+            return;
+        }
+        response->set_message("Accepted stream");
+    }
+
+private:
+    StreamReceiver _receiver;
+    brpc::StreamId _sd;
+};
+
+int main(int argc, char* argv[]) {
+    // Parse gflags. We recommend you to use gflags as well.
+    GFLAGS_NAMESPACE::ParseCommandLineFlags(&argc, &argv, true);
+
+    // Generally you only need one Server.
+    brpc::Server server;
+
+    // Instance of your service.
+    StreamingEchoService echo_service_impl;
+
+    // Add the service into server. Notice the second parameter, because the
+    // service is put on stack, we don't want server to delete it, otherwise
+    // use brpc::SERVER_OWNS_SERVICE.
+    if (server.AddService(&echo_service_impl, 
+                          brpc::SERVER_DOESNT_OWN_SERVICE) != 0) {
+        LOG(ERROR) << "Fail to add service";
+        return -1;
+    }
+
+    // Start the server. 
+    brpc::ServerOptions options;
+    options.idle_timeout_sec = FLAGS_idle_timeout_s;
+    if (server.Start(FLAGS_port, &options) != 0) {
+        LOG(ERROR) << "Fail to start EchoServer";
+        return -1;
+    }
+
+    // Wait until Ctrl-C is pressed, then Stop() and Join() the server.
+    server.RunUntilAskedToQuit();
+    return 0;
+}