Add service registry

registry/service/watcher.go

@@ -0,0 +1,49 @@
+package service
+
+import (
+	"github.com/micro/go-micro/registry"
+	pb "github.com/micro/go-micro/registry/proto"
+)
+
+type serviceWatcher struct {
+	stream pb.Registry_WatchService
+	closed chan bool
+}
+
+func (s *serviceWatcher) Next() (*registry.Result, error) {
+	for {
+		// check if closed
+		select {
+		case <-s.closed:
+			return nil, registry.ErrWatcherStopped
+		default:
+		}
+
+		r, err := s.stream.Recv()
+		if err != nil {
+			return nil, err
+		}
+
+		return &registry.Result{
+			Action:  r.Action,
+			Service: toService(r.Service),
+		}, nil
+	}
+}
+
+func (s *serviceWatcher) Stop() {
+	select {
+	case <-s.closed:
+		return
+	default:
+		close(s.closed)
+		s.stream.Close()
+	}
+}
+
+func newWatcher(stream pb.Registry_WatchService) registry.Watcher {
+	return &serviceWatcher{
+		stream: stream,
+		closed: make(chan bool),
+	}
+}