From d5be2136ade68d94b9d01859bd887e947e8d5ee0 Mon Sep 17 00:00:00 2001
From: Asim Aslam <asim@aslam.me>
Date: Wed, 4 Sep 2019 12:16:31 +0100
Subject: [PATCH] cleanup new message creation

---
 tunnel/default.go | 16 +++++-----
 tunnel/session.go | 78 +++++++++++++++--------------------------------
 tunnel/tunnel.go  |  1 -
 3 files changed, 32 insertions(+), 63 deletions(-)

diff --git a/tunnel/default.go b/tunnel/default.go
index f1a0eaac..0ab11ea2 100644
--- a/tunnel/default.go
+++ b/tunnel/default.go
@@ -830,15 +830,13 @@ func (t *tun) Dial(channel string, opts ...DialOption) (Session, error) {
 
 	// shit fuck
 	if !c.discovered {
-		t.send <- &message{
-			typ:       "discover",
-			tunnel:    t.id,
-			channel:   channel,
-			session:   c.session,
-			broadcast: true,
-			outbound:  true,
-			errChan:   c.errChan,
-		}
+		msg := c.newMessage("discover")
+		msg.broadcast = true
+		msg.outbound = true
+		msg.link = ""
+
+		// send the discovery message
+		t.send <- msg
 
 		select {
 		case err := <-c.errChan:
diff --git a/tunnel/session.go b/tunnel/session.go
index 9e431296..eb3cc170 100644
--- a/tunnel/session.go
+++ b/tunnel/session.go
@@ -91,10 +91,9 @@ func (s *session) Channel() string {
 	return s.channel
 }
 
-// Open will fire the open message for the session. This is called by the dialler.
-func (s *session) Open() error {
-	msg := &message{
-		typ:       "open",
+func (s *session) newMessage(typ string) *message {
+	return &message{
+		typ:       typ,
 		tunnel:    s.tunnel,
 		channel:   s.channel,
 		session:   s.session,
@@ -104,6 +103,12 @@ func (s *session) Open() error {
 		link:      s.link,
 		errChan:   s.errChan,
 	}
+}
+
+// Open will fire the open message for the session. This is called by the dialler.
+func (s *session) Open() error {
+	// create a new message
+	msg := s.newMessage("open")
 
 	// send open message
 	s.send <- msg
@@ -146,17 +151,7 @@ func (s *session) Open() error {
 
 // Accept sends the accept response to an open message from a dialled connection
 func (s *session) Accept() error {
-	msg := &message{
-		typ:       "accept",
-		tunnel:    s.tunnel,
-		channel:   s.channel,
-		session:   s.session,
-		outbound:  s.outbound,
-		loopback:  s.loopback,
-		multicast: s.multicast,
-		link:      s.link,
-		errChan:   s.errChan,
-	}
+	msg := s.newMessage("accept")
 
 	// send the accept message
 	select {
@@ -181,15 +176,11 @@ func (s *session) Accept() error {
 
 // Announce sends an announcement to notify that this session exists. This is primarily used by the listener.
 func (s *session) Announce() error {
-	msg := &message{
-		typ:       "announce",
-		tunnel:    s.tunnel,
-		channel:   s.channel,
-		session:   s.session,
-		outbound:  s.outbound,
-		loopback:  s.loopback,
-		multicast: s.multicast,
-	}
+	msg := s.newMessage("announce")
+	// we don't need an error back
+	msg.errChan = nil
+	// we don't need the link
+	msg.link = ""
 
 	select {
 	case s.send <- msg:
@@ -218,26 +209,14 @@ func (s *session) Send(m *transport.Message) error {
 		data.Header[k] = v
 	}
 
-	// append to backlog
-	msg := &message{
-		typ:       "session",
-		tunnel:    s.tunnel,
-		channel:   s.channel,
-		session:   s.session,
-		outbound:  s.outbound,
-		loopback:  s.loopback,
-		multicast: s.multicast,
-		data:      data,
-		// specify the link on which to send this
-		// it will be blank for dialled sessions
-		link: s.link,
-		// error chan
-		errChan: s.errChan,
-	}
+	// create a new message
+	msg := s.newMessage("session")
+	// set the data
+	msg.data = data
 
-	// if not multicast then set link
-	if !s.multicast {
-		msg.link = s.link
+	// if multicast don't set the link
+	if s.multicast {
+		msg.link = ""
 	}
 
 	log.Debugf("Appending %+v to send backlog", msg)
@@ -289,16 +268,9 @@ func (s *session) Close() error {
 		close(s.closed)
 
 		// append to backlog
-		msg := &message{
-			typ:       "close",
-			tunnel:    s.tunnel,
-			channel:   s.channel,
-			session:   s.session,
-			outbound:  s.outbound,
-			loopback:  s.loopback,
-			multicast: s.multicast,
-			link:      s.link,
-		}
+		msg := s.newMessage("close")
+		// no error response on close
+		msg.errChan = nil
 
 		// send the close message
 		select {
diff --git a/tunnel/tunnel.go b/tunnel/tunnel.go
index 9566f3b9..e76f8437 100644
--- a/tunnel/tunnel.go
+++ b/tunnel/tunnel.go
@@ -15,7 +15,6 @@ var (
 	DefaultDialTimeout = time.Second * 5
 )
 
-
 // Tunnel creates a gre tunnel on top of the go-micro/transport.
 // It establishes multiple streams using the Micro-Tunnel-Channel header
 // and Micro-Tunnel-Session header. The tunnel id is a hash of