Channels work now I think

book.go

@@ -0,0 +1,92 @@
+package main
+
+import (
+	"io"
+	"log"
+)
+
+type Book struct {
+	entries map[string]*Repeater
+	events chan bookEvent
+}
+
+
+func NewBook() Book {
+	return Book{
+		entries: make(map[string]*Repeater),
+		events: make(chan bookEvent, 5),
+	}
+}
+
+type bookEventType int
+const (
+	joinEvent = bookEventType(iota)
+	partEvent
+	sendEvent
+)
+
+type bookEvent struct {
+	eventType bookEventType
+	name string
+	w io.Writer
+	p []byte
+}
+
+func (b Book) Join(name string, w io.Writer) {
+	b.events <- bookEvent{
+		eventType: joinEvent,
+		name: name,
+		w: w,
+	}
+}
+
+func (b Book) Part(name string, w io.Writer) {
+	b.events <- bookEvent{
+		eventType: partEvent,
+		name: name,
+		w: w,
+	}
+}
+
+func (b Book) Send(name string, p []byte) {
+	b.events <- bookEvent{
+		eventType: sendEvent,
+		name: name,
+		p: p,
+	}
+}
+
+func (b Book) Run() {
+	for {
+		b.loop()
+	}
+}
+
+func (b Book) loop() {
+	event := <-b.events
+	repeater, ok := b.entries[event.name]
+
+	switch event.eventType {
+	case joinEvent:
+		if ! ok {
+			repeater = NewRepeater()
+			b.entries[event.name] = repeater
+		}
+		repeater.Join(event.w)
+	case partEvent:
+		if ! ok {
+			log.Println("WARN: Parting an empty channel:", event.name)
+			break
+		}
+		repeater.Part(event.w)
+		if len(repeater.subscribers) == 0 {
+			delete(b.entries, event.name)
+		}
+	case sendEvent:
+		if ! ok {
+			log.Println("WARN: Sending to an empty channel:", event.name)
+			break
+		}
+		repeater.Send(event.p)
+	}
+}

book_test.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestBook(t *testing.T) {
+	b := NewBook()
+
+	buf1 := bytes.NewBufferString("buf1")
+	b.Join("moo", buf1)
+	b.loop()
+	if len(b.entries) != 1 {
+		t.Error("Wrong number of entries")
+	}
+	
+	// Send to an empty channel
+	b.Send("merf", []byte("goober"))
+	b.loop()
+	if buf1.String() != "buf1" {
+		t.Error("Sending to empty channel sent to non-empty channel")
+	}
+	
+	// Send to a non-empty channel!
+	b.Send("moo", []byte("goober"))
+	b.loop()
+	if buf1.String() != "buf1goober" {
+		t.Error("Sending didn't work")
+	}
+
+	// Join another client
+	buf2 := bytes.NewBufferString("buf2")
+	b.Join("moo", buf2)
+	b.loop()
+
+	// Send to both
+	b.Send("moo", []byte("snerk"))
+	b.loop()
+	if buf1.String() != "buf1goobersnerk" {
+		t.Error("Send to 2-member channel busted", buf1)
+	}
+	if buf2.String() != "buf2snerk" {
+		t.Error("Send to 2-member channel busted", buf2)
+	}
+	
+	// Part a client
+	b.Part("moo", buf1)
+	b.loop()
+	
+	b.Send("moo", []byte("peanut"))
+	b.loop()
+	if buf1.String() != "buf1goobersnerk" {
+		t.Error("Parted channel but still getting messages", buf1)
+	}
+	if buf2.String() != "buf2snerkpeanut" {
+		t.Error("Someone else parting somehow messed up sends", buf2)
+	}
+}

main.go

@@ -6,6 +6,22 @@ import (
 	"golang.org/x/net/websocket"
 )
 
+func (ch Channel) Write(msg Message) {
+	for i, o := range clients {
+		if o.active == false {
+			nclients := len(clients)
+			clients[i] = clients[nclients - 1]
+			clients[nclients - 1] = Client{}
+			clients = clients[:nclients - 1]
+		} else if o == c {
+			// Don't send it back to the sending client
+		} else {
+			o.ws.Write(msg)
+		}
+	}
+}
+
+
 type Client struct {
 	ws *websocket.Conn
 	active bool
@@ -14,6 +30,7 @@ type Client struct {
 var clients []Client
 
 func (c Client) Chat() {
+	websocket.Message.Receive
 	for c.active {
 		buf := make([]byte, 800)
 		n, err := c.ws.Read(buf)
@@ -21,19 +38,6 @@ func (c Client) Chat() {
 			c.active = false
 		}
 		buf = buf[:n]
-
-		for i, o := range clients {
-			if o.active == false {
-				nclients := len(clients)
-				clients[i] = clients[nclients - 1]
-				clients[nclients - 1] = Client{}
-				clients = clients[:nclients - 1]
-			} else if o == c {
-				// Don't send it back to the sending client
-			} else {
-				o.ws.Write(buf)
-			}
-		}
 	}
 }
 

repeater.go

@@ -5,62 +5,31 @@ import (
 )
 
 type Repeater struct {
-	joins chan io.Writer
-	parts chan io.Writer
-	sends chan []byte
 	subscribers []io.Writer
 }
 
 func NewRepeater() *Repeater {
 	return &Repeater{
-		joins: make(chan io.Writer, 5),
-		parts: make(chan io.Writer, 5),
-		sends: make(chan []byte, 5),
 		subscribers: make([]io.Writer, 0, 20),
 	}
 }
 
 func (r *Repeater) Join(w io.Writer) {
-	r.joins <- w
+	r.subscribers = append(r.subscribers, w)
 }
 
 func (r *Repeater) Part(w io.Writer) {
-	r.parts <- w
+	for i, s := range r.subscribers {
+		if s == w {
+			nsubs := len(r.subscribers)
+			r.subscribers[i] = r.subscribers[nsubs-1]
+			r.subscribers = r.subscribers[:nsubs-1]
+		}
+	}
 }
 
 func (r *Repeater) Send(p []byte) {
-	r.sends <- p
-}
-
-func (r *Repeater) Close() {
-	close(r.sends)
-}
-
-func (r *Repeater) Run() {
-	for r.loop() {}
-}
-
-func (r *Repeater) loop() bool {
-	select {
-	case w := <- r.joins:
-		// Add subscriber
-		r.subscribers = append(r.subscribers, w)
-	case w := <- r.parts:
-		// Remove subscriber
-		for i, s := range r.subscribers {
-			if s == w {
-				nsubs := len(r.subscribers)
-				r.subscribers[i] = r.subscribers[nsubs-1]
-				r.subscribers = r.subscribers[:nsubs-1]
-			}
-		}
-	case p, ok := <- r.sends:
-		if ! ok {
-			return false
-		}
-		for _, s := range r.subscribers {
-			s.Write(p)
-		}
+	for _, s := range r.subscribers {
+		s.Write(p)
 	}
-	return true
 }

repeater_test.go

@@ -10,21 +10,17 @@ func TestRepeater(t *testing.T) {
 
 	buf1 := bytes.NewBufferString("buf1")
 	r.Join(buf1)
-	r.loop()
 	if len(r.subscribers) != 1 {
 		t.Error("Joining did nothing")
 	}
 	r.Send([]byte("moo"))
-	r.loop()
 	if buf1.String() != "buf1moo" {
 		t.Error("Client 1 not repeating", buf1)
 	}
 	
 	buf2 := bytes.NewBufferString("buf2")
 	r.Join(buf2)
-	r.loop()
 	r.Send([]byte("bar"))
-	r.loop()
 	if buf1.String() != "buf1moobar" {
 		t.Error("Client 1 not repeating", buf1)
 	}
@@ -33,21 +29,11 @@ func TestRepeater(t *testing.T) {
 	}
 	
 	r.Part(buf1)
-	r.loop()
 	r.Send([]byte("baz"))
-	r.loop()
 	if buf1.String() != "buf1moobar" {
 		t.Error("Client 1 still getting data after part", buf1)
 	}
 	if buf2.String() != "buf2barbaz" {
 		t.Error("Client 2 not getting data after part", buf2)
 	}
-	
-	r.Close()
-	if r.loop() {
-		t.Error("Closed send didn't terminate loop")
-	}
-	if r.loop() {
-		t.Error("Second loop in terminated channel didn't terminate")
-	}
 }

static/index.html

@@ -7,7 +7,7 @@
   </head>
   <body>
     <div>
-      <img src="1280px-Morse-code-tree.svg.png">
+      <img src="code-tree.png">
     </div>
 
     <div>