From c407e097e2f3a7953082aa32e26fbfaf6fcaff67 Mon Sep 17 00:00:00 2001
From: Gyu-Ho Lee <gyuhox@gmail.com>
Date: Fri, 14 Apr 2017 09:24:52 -0700
Subject: [PATCH] embed: gracefully shut down gRPC server

Fix https://github.com/coreos/etcd/issues/7322.

Signed-off-by: Gyu-Ho Lee <gyuhox@gmail.com>
---
 embed/etcd.go  | 8 ++++++++
 embed/serve.go | 9 ++++++++-
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/embed/etcd.go b/embed/etcd.go
index da1d8f610c3..4d23a04009c 100644
--- a/embed/etcd.go
+++ b/embed/etcd.go
@@ -148,6 +148,14 @@ func (e *Etcd) Config() Config {
 func (e *Etcd) Close() {
 	e.closeOnce.Do(func() { close(e.stopc) })
 
+	// (gRPC server) stops accepting new connections,
+	// RPCs, and blocks until all pending RPCs are finished
+	for _, sctx := range e.sctxs {
+		for gs := range sctx.grpcServerC {
+			gs.GracefulStop()
+		}
+	}
+
 	for _, sctx := range e.sctxs {
 		sctx.cancel()
 	}
diff --git a/embed/serve.go b/embed/serve.go
index 46634b7c5f1..02c093ff81c 100644
--- a/embed/serve.go
+++ b/embed/serve.go
@@ -52,11 +52,14 @@ type serveCtx struct {
 
 	userHandlers    map[string]http.Handler
 	serviceRegister func(*grpc.Server)
+	grpcServerC     chan *grpc.Server
 }
 
 func newServeCtx() *serveCtx {
 	ctx, cancel := context.WithCancel(context.Background())
-	return &serveCtx{ctx: ctx, cancel: cancel, userHandlers: make(map[string]http.Handler)}
+	return &serveCtx{ctx: ctx, cancel: cancel, userHandlers: make(map[string]http.Handler),
+		grpcServerC: make(chan *grpc.Server, 2), // in case sctx.insecure,sctx.secure true
+	}
 }
 
 // serve accepts incoming connections on the listener l,
@@ -72,8 +75,11 @@ func (sctx *serveCtx) serve(s *etcdserver.EtcdServer, tlscfg *tls.Config, handle
 	servElection := v3election.NewElectionServer(v3c)
 	servLock := v3lock.NewLockServer(v3c)
 
+	defer close(sctx.grpcServerC)
+
 	if sctx.insecure {
 		gs := v3rpc.Server(s, nil)
+		sctx.grpcServerC <- gs
 		v3electionpb.RegisterElectionServer(gs, servElection)
 		v3lockpb.RegisterLockServer(gs, servLock)
 		if sctx.serviceRegister != nil {
@@ -103,6 +109,7 @@ func (sctx *serveCtx) serve(s *etcdserver.EtcdServer, tlscfg *tls.Config, handle
 
 	if sctx.secure {
 		gs := v3rpc.Server(s, tlscfg)
+		sctx.grpcServerC <- gs
 		v3electionpb.RegisterElectionServer(gs, servElection)
 		v3lockpb.RegisterLockServer(gs, servLock)
 		if sctx.serviceRegister != nil {