discovery: device discovery

discovery/listener.go

@@ -0,0 +1,40 @@
+package discovery
+
+import (
+	"context"
+	"net"
+
+	"github.com/bboozzoo/mconnect/logger"
+)
+
+type Listener struct {
+	conn *net.UDPConn
+}
+
+func NewListener() (*Listener, error) {
+	addr := net.UDPAddr{
+		Port: 1714,
+	}
+	conn, err := net.ListenUDP("udp", &addr)
+	if err != nil {
+		return nil, err
+	}
+
+	listener := &Listener{
+		conn: conn,
+	}
+
+	return listener, nil
+}
+
+func (l *Listener) Receive(ctx context.Context) {
+	log := logger.FromContext(ctx)
+	buf := make([]byte, 4096)
+	count, addr, err := l.conn.ReadFromUDP(buf)
+	if err != nil {
+		log.Printf("listen failed: %v", err)
+	}
+
+	log.Printf("got %v bytes from %v", count, addr)
+	log.Printf("data:\n%s", string(buf))
+}