add observer

registry/observer.go

@@ -0,0 +1,39 @@
+package registry
+
+import (
+	"context"
+
+	"github.com/go-gost/core/observer"
+)
+
+type observerRegistry struct {
+	registry[observer.Observer]
+}
+
+func (r *observerRegistry) Register(name string, v observer.Observer) error {
+	return r.registry.Register(name, v)
+}
+
+func (r *observerRegistry) Get(name string) observer.Observer {
+	if name != "" {
+		return &observerWrapper{name: name, r: r}
+	}
+	return nil
+}
+
+func (r *observerRegistry) get(name string) observer.Observer {
+	return r.registry.Get(name)
+}
+
+type observerWrapper struct {
+	name string
+	r    *observerRegistry
+}
+
+func (w *observerWrapper) Observe(ctx context.Context, events []observer.Event, opts ...observer.Option) error {
+	v := w.r.get(w.name)
+	if v == nil {
+		return nil
+	}
+	return v.Observe(ctx, events, opts...)
+}