Return error messages for some exposed methods, fix panic when connec…

…tion is closed. Close olahol#21.

hub.go

@@ -38,8 +38,6 @@ loop:
 			if _, ok := h.sessions[s]; ok {
 				h.rwmutex.Lock()
 				delete(h.sessions, s)
-				s.conn.Close()
-				close(s.output)
 				h.rwmutex.Unlock()
 			}
 		case m := <-h.broadcast:
@@ -58,8 +56,7 @@ loop:
 			h.rwmutex.Lock()
 			for s := range h.sessions {
 				delete(h.sessions, s)
-				s.conn.Close()
-				close(s.output)
+				s.Close()
 			}
 			h.open = false
 			h.rwmutex.Unlock()
@@ -68,6 +65,12 @@ loop:
 	}
 }
 
+func (h *hub) closed() bool {
+	h.rwmutex.RLock()
+	defer h.rwmutex.RUnlock()
+	return !h.open
+}
+
 func (h *hub) len() int {
 	h.rwmutex.RLock()
 	defer h.rwmutex.RUnlock()

melody.go

@@ -1,6 +1,7 @@
 package melody
 
 import (
+	"errors"
 	"github.com/gorilla/websocket"
 	"net/http"
 	"sync"
@@ -79,12 +80,15 @@ func (m *Melody) HandleError(fn func(*Session, error)) {
 }
 
 // HandleRequest upgrades http requests to websocket connections and dispatches them to be handled by the melody instance.
-func (m *Melody) HandleRequest(w http.ResponseWriter, r *http.Request) {
+func (m *Melody) HandleRequest(w http.ResponseWriter, r *http.Request) error {
+	if m.hub.closed() {
+		return errors.New("Melody instance is closed.")
+	}
+
 	conn, err := m.Upgrader.Upgrade(w, r, nil)
 
 	if err != nil {
-		m.errorHandler(nil, err)
-		return
+		return err
 	}
 
 	session := &Session{
@@ -93,7 +97,8 @@ func (m *Melody) HandleRequest(w http.ResponseWriter, r *http.Request) {
 		conn:    conn,
 		output:  make(chan *envelope, m.Config.MessageBufferSize),
 		melody:  m,
-		lock:    &sync.Mutex{},
+		open:    true,
+		rwmutex: &sync.RWMutex{},
 	}
 
 	m.hub.register <- session
@@ -104,54 +109,88 @@ func (m *Melody) HandleRequest(w http.ResponseWriter, r *http.Request) {
 
 	session.readPump()
 
-	if m.hub.open {
+	if !m.hub.closed() {
 		m.hub.unregister <- session
 	}
 
-	go m.disconnectHandler(session)
+	session.close()
+
+	m.disconnectHandler(session)
+
+	return nil
 }
 
 // Broadcast broadcasts a text message to all sessions.
-func (m *Melody) Broadcast(msg []byte) {
+func (m *Melody) Broadcast(msg []byte) error {
+	if m.hub.closed() {
+		return errors.New("Melody instance is closed.")
+	}
+
 	message := &envelope{t: websocket.TextMessage, msg: msg}
 	m.hub.broadcast <- message
+
+	return nil
 }
 
 // BroadcastFilter broadcasts a text message to all sessions that fn returns true for.
-func (m *Melody) BroadcastFilter(msg []byte, fn func(*Session) bool) {
+func (m *Melody) BroadcastFilter(msg []byte, fn func(*Session) bool) error {
+	if m.hub.closed() {
+		return errors.New("Melody instance is closed.")
+	}
+
 	message := &envelope{t: websocket.TextMessage, msg: msg, filter: fn}
 	m.hub.broadcast <- message
+
+	return nil
 }
 
 // BroadcastOthers broadcasts a text message to all sessions except session s.
-func (m *Melody) BroadcastOthers(msg []byte, s *Session) {
-	m.BroadcastFilter(msg, func(q *Session) bool {
+func (m *Melody) BroadcastOthers(msg []byte, s *Session) error {
+	return m.BroadcastFilter(msg, func(q *Session) bool {
 		return s != q
 	})
 }
 
 // BroadcastBinary broadcasts a binary message to all sessions.
-func (m *Melody) BroadcastBinary(msg []byte) {
+func (m *Melody) BroadcastBinary(msg []byte) error {
+	if m.hub.closed() {
+		return errors.New("Melody instance is closed.")
+	}
+
 	message := &envelope{t: websocket.BinaryMessage, msg: msg}
 	m.hub.broadcast <- message
+
+	return nil
 }
 
 // BroadcastBinaryFilter broadcasts a binary message to all sessions that fn returns true for.
-func (m *Melody) BroadcastBinaryFilter(msg []byte, fn func(*Session) bool) {
+func (m *Melody) BroadcastBinaryFilter(msg []byte, fn func(*Session) bool) error {
+	if m.hub.closed() {
+		return errors.New("Melody instance is closed.")
+	}
+
 	message := &envelope{t: websocket.BinaryMessage, msg: msg, filter: fn}
 	m.hub.broadcast <- message
+
+	return nil
 }
 
 // BroadcastBinaryOthers broadcasts a binary message to all sessions except session s.
-func (m *Melody) BroadcastBinaryOthers(msg []byte, s *Session) {
-	m.BroadcastBinaryFilter(msg, func(q *Session) bool {
+func (m *Melody) BroadcastBinaryOthers(msg []byte, s *Session) error {
+	return m.BroadcastBinaryFilter(msg, func(q *Session) bool {
 		return s != q
 	})
 }
 
 // Close closes the melody instance and all connected sessions.
-func (m *Melody) Close() {
+func (m *Melody) Close() error {
+	if m.hub.closed() {
+		return errors.New("Melody instance is already closed.")
+	}
+
 	m.hub.exit <- true
+
+	return nil
 }
 
 // Len return the number of connected sessions.

melody_test.go

@@ -80,6 +80,43 @@ func TestEcho(t *testing.T) {
 	}
 }
 
+func TestWriteClosed(t *testing.T) {
+	echo := NewTestServerHandler(func(session *Session, msg []byte) {
+		session.Write(msg)
+	})
+	server := httptest.NewServer(echo)
+	defer server.Close()
+
+	fn := func(msg string) bool {
+		conn, err := NewDialer(server.URL)
+
+		if err != nil {
+			t.Error(err)
+			return false
+		}
+
+		conn.WriteMessage(websocket.TextMessage, []byte(msg))
+
+		echo.m.HandleConnect(func(s *Session) {
+			s.Close()
+		})
+
+		echo.m.HandleDisconnect(func(s *Session) {
+			err := s.Write([]byte("hello world"))
+
+			if err == nil {
+				t.Error("should be an error")
+			}
+		})
+
+		return true
+	}
+
+	if err := quick.Check(fn, nil); err != nil {
+		t.Error(err)
+	}
+}
+
 func TestLen(t *testing.T) {
 	rand.Seed(time.Now().UnixNano())
 
@@ -641,3 +678,47 @@ func TestPong(t *testing.T) {
 		t.Error("should have fired pong handler")
 	}
 }
+
+func BenchmarkSessionWrite(b *testing.B) {
+	echo := NewTestServerHandler(func(session *Session, msg []byte) {
+		session.Write(msg)
+	})
+	server := httptest.NewServer(echo)
+	conn, _ := NewDialer(server.URL)
+	defer server.Close()
+	defer conn.Close()
+
+	for n := 0; n < b.N; n++ {
+		conn.WriteMessage(websocket.TextMessage, []byte("test"))
+		conn.ReadMessage()
+	}
+}
+
+func BenchmarkBroadcast(b *testing.B) {
+	echo := NewTestServerHandler(func(session *Session, msg []byte) {
+		session.Write(msg)
+	})
+	server := httptest.NewServer(echo)
+	defer server.Close()
+
+	conns := make([]*websocket.Conn, 0)
+
+	num := 100
+
+	for i := 0; i < num; i++ {
+		conn, _ := NewDialer(server.URL)
+		conns = append(conns, conn)
+	}
+
+	for n := 0; n < b.N; n++ {
+		echo.m.Broadcast([]byte("test"))
+
+		for i := 0; i < num; i++ {
+			conns[i].ReadMessage()
+		}
+	}
+
+	for i := 0; i < num; i++ {
+		conns[i].Close()
+	}
+}