add Tick() export and DialConnManual for JS-driven send loop in WASM

client.go

@@ -83,6 +83,29 @@ func DialConn(conn Conn, ocb *OCB) (*Client, error) {
 	return c, nil
 }
 
+// DialConnManual creates a mosh client without an internal sendLoop.
+// The caller must call Tick() periodically (e.g., every 8-16ms) to flush
+// outgoing datagrams. Use this in WASM where Go timers are unreliable.
+func DialConnManual(conn Conn, ocb *OCB) (*Client, error) {
+	c := &Client{
+		conn:             conn,
+		transport:        NewTransport(ocb, false),
+		ocb:              ocb,
+		outputC:          make(chan struct{}, 1),
+		done:             make(chan struct{}),
+		sentActionCounts: make(map[uint64]int),
+	}
+
+	c.wg.Add(1)
+	go c.recvLoop()
+
+	// Send initial keepalive to associate with the server.
+	c.transport.ForceNextSend()
+	c.tick()
+
+	return c, nil
+}
+
 // Send sends keystrokes to the server.
 func (c *Client) Send(keys []byte) {
 	c.actionsMu.Lock()
@@ -147,6 +170,13 @@ func (c *Client) Transport() *Transport {
 	return c.transport
 }
 
+// Tick flushes pending actions as mosh datagrams. Call this periodically
+// from an external timer (e.g., JS setInterval in WASM) when the internal
+// sendLoop is not used.
+func (c *Client) Tick() {
+	c.tick()
+}
+
 func (c *Client) tick() {
 	// Batch: compute diff from accumulated actions.
 	c.actionsMu.Lock()

cmd/mosh-wasm/main.go

@@ -72,7 +72,8 @@ func newSession(url, key string) (*session, error) {
 		return nil, err
 	}
 
-	client, err := mosh.DialConn(conn, ocb)
+	// Use DialConnManual — no internal sendLoop. JS drives Tick() via setInterval.
+	client, err := mosh.DialConnManual(conn, ocb)
 	if err != nil {
 		conn.Close()
 		return nil, err
@@ -90,6 +91,8 @@ func (s *session) jsObject() js.Value {
 		}
 		data := args[0].String()
 		s.client.Send([]byte(data))
+		// Tick immediately so keystrokes go out without waiting for the interval.
+		s.client.Tick()
 		return nil
 	}))
 
@@ -100,6 +103,13 @@ func (s *session) jsObject() js.Value {
 		cols := args[0].Int()
 		rows := args[1].Int()
 		s.client.Resize(uint16(cols), uint16(rows))
+		s.client.Tick()
+		return nil
+	}))
+
+	// tick() — flush pending datagrams. Called by JS setInterval.
+	obj.Set("tick", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
+		s.client.Tick()
 		return nil
 	}))