Added flag to disable http/2 support (still enabled by default)

main.go

@@ -9,10 +9,14 @@ import (
 	"github.com/mholt/caddy/server"
 )
 
-var conf string
+var (
+	conf  string
+	http2 bool
+)
 
 func init() {
 	flag.StringVar(&conf, "conf", server.DefaultConfigFile, "the configuration file to use")
+	flag.BoolVar(&http2, "http2", true, "enable HTTP/2 support") // flag temporary until http2 merged into std lib
 }
 
 func main() {
@@ -34,6 +38,7 @@ func main() {
 		if err != nil {
 			log.Fatal(err)
 		}
+		s.HTTP2 = http2
 		wg.Add(1)
 		go func(s *server.Server) {
 			defer wg.Done()

server/server.go

@@ -26,6 +26,7 @@ var servers = make(map[string]*Server)
 // Server represents an instance of a server, which serves
 // static content at a particular address (host and port).
 type Server struct {
+	HTTP2      bool // temporary while http2 is not in std lib (TODO: remove flag when part of std lib)
 	config     config.Config
 	fileServer middleware.Handler
 	stack      middleware.Handler
@@ -83,8 +84,10 @@ func (s *Server) Serve() error {
 		Handler: s,
 	}
 
+	if s.HTTP2 {
 		// TODO: This call may not be necessary after HTTP/2 is merged into std lib
 		http2.ConfigureServer(server, nil)
+	}
 
 	// Execute shutdown commands on exit
 	go func() {