Close not working properly on gRPC graceful stop

[elvizlai]

example code:

package main

import (
	"fmt"
	"net"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/soheilhy/cmux"
	"google.golang.org/grpc"
)

func main() {
	lis, err := net.Listen("tcp", ":8080")
	if err != nil {
		panic(err)
	}

	mux := cmux.New(lis)
	grpcL := mux.Match(cmux.HTTP2HeaderField("content-type", "application/grpc"))
	_ = grpcL

	s := grpc.NewServer()
	// xxx.RegisterXXXServiceServer(s, XXXIMPL)

	go func() {
		// FIXME: using muxed grpcL here can not graceful stop
		err = s.Serve(lis)
		fmt.Println(err)
	}()

	fmt.Println("wait for sig")
	c := make(chan os.Signal, 1)
	signal.Notify(c, []os.Signal{syscall.SIGTERM, syscall.SIGQUIT, syscall.SIGINT}...)
	<-c

        // FIXME: hangs on when start server with grpcL
	s.GracefulStop()

	fmt.Println("stopped")
	time.Sleep(time.Second * 1)
}

[jgraettinger]

See #76