first-commit

modules/graceful/server_hooks.go

@@ -0,0 +1,73 @@
+// Copyright 2019 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package graceful
+
+import (
+	"os"
+	"runtime"
+
+	"code.gitea.io/gitea/modules/log"
+)
+
+// awaitShutdown waits for the shutdown signal from the Manager
+func (srv *Server) awaitShutdown() {
+	select {
+	case <-GetManager().IsShutdown():
+		// Shutdown
+		srv.doShutdown()
+	case <-GetManager().IsHammer():
+		// Hammer
+		srv.doShutdown()
+		srv.doHammer()
+	}
+	<-GetManager().IsHammer()
+	srv.doHammer()
+}
+
+// shutdown closes the listener so that no new connections are accepted
+// and starts a goroutine that will hammer (stop all running requests) the server
+// after setting.GracefulHammerTime.
+func (srv *Server) doShutdown() {
+	// only shutdown if we're running.
+	if srv.getState() != stateRunning {
+		return
+	}
+
+	srv.setState(stateShuttingDown)
+
+	if srv.OnShutdown != nil {
+		srv.OnShutdown()
+	}
+	err := srv.listener.Close()
+	if err != nil {
+		log.Error("PID: %d Listener.Close() error: %v", os.Getpid(), err)
+	} else {
+		log.Info("PID: %d Listener (%s) closed.", os.Getpid(), srv.listener.Addr())
+	}
+}
+
+func (srv *Server) doHammer() {
+	defer func() {
+		// We call srv.wg.Done() until it panics.
+		// This happens if we call Done() when the WaitGroup counter is already at 0
+		// So if it panics -> we're done, Serve() will return and the
+		// parent will goroutine will exit.
+		if r := recover(); r != nil {
+			log.Error("WaitGroup at 0: Error: %v", r)
+		}
+	}()
+	if srv.getState() != stateShuttingDown {
+		return
+	}
+	log.Warn("Forcefully shutting down parent")
+	for {
+		if srv.getState() == stateTerminate {
+			break
+		}
+		srv.wg.Done()
+
+		// Give other goroutines a chance to finish before we forcibly stop them.
+		runtime.Gosched()
+	}
+}