Revert D63971252

Summary:
This diff reverts D63971252
removed by mistake, used in github

Reviewed By: avasylev

Differential Revision: D64762130

fbshipit-source-id: c9c78cf9f772cebae5f910ae6b9ffae2969c33ee

example_grpc/GrpcSignalHandler.cpp

@@ -0,0 +1,52 @@
+/* Copyright (C) 2018-present, Facebook, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "GrpcSignalHandler.h"
+
+#include <folly/io/async/EventBase.h>
+
+namespace lb {
+namespace katran {
+
+GrpcSignalHandler::GrpcSignalHandler(
+    std::shared_ptr<folly::EventBase> evb,
+    grpc::Server* server,
+    int32_t delay)
+    : folly::AsyncSignalHandler(evb.get()), delay_(delay) {
+  server_ = server;
+  evb_ = evb;
+};
+
+void GrpcSignalHandler::signalReceived(int signum) noexcept {
+  if (shutdownScheduled_) {
+    LOG(INFO) << "Ignoring signal: " << signum << " as we already scheduled"
+              << " sighandler to run.";
+    return;
+  };
+  LOG(INFO) << "Signal: " << signum << ", stopping service in " << delay_
+            << " milliseconds.";
+  evb_->runInEventBaseThread([this]() {
+    evb_->runAfterDelay(
+        [this]() {
+          LOG(INFO) << "Stopping Katran!";
+          server_->Shutdown();
+        },
+        delay_);
+  });
+  shutdownScheduled_ = true;
+};
+} // namespace katran
+} // namespace lb

example_grpc/GrpcSignalHandler.h

@@ -0,0 +1,57 @@
+/* Copyright (C) 2018-present, Facebook, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#pragma once
+
+#include <memory>
+
+#include <folly/io/async/AsyncSignalHandler.h>
+#include <grpc++/grpc++.h>
+
+namespace folly {
+class EventBase;
+}
+
+namespace lb {
+namespace katran {
+
+/**
+ * class which implements sighandler for katran's grpc server
+ */
+class GrpcSignalHandler : public folly::AsyncSignalHandler {
+ public:
+  /**
+   * @param EventBase* evb event base thread
+   * @param grpc::Server* server katran's grpc server
+   * @param int32_t delay in ms between recving signal and stopping katran
+   */
+  GrpcSignalHandler(
+      std::shared_ptr<folly::EventBase> evb,
+      grpc::Server* server,
+      int32_t delay);
+  ~GrpcSignalHandler() override {}
+
+  void signalReceived(int signum) noexcept override;
+
+ private:
+  grpc::Server* server_;
+  std::shared_ptr<folly::EventBase> evb_;
+  int32_t delay_;
+  bool shutdownScheduled_{false};
+};
+
+} // namespace katran
+} // namespace lb