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...)
+}

registry/registry.go

@@ -16,6 +16,7 @@ import (
 	"github.com/go-gost/core/limiter/rate"
 	"github.com/go-gost/core/limiter/traffic"
 	"github.com/go-gost/core/logger"
+	"github.com/go-gost/core/observer"
 	"github.com/go-gost/core/recorder"
 	reg "github.com/go-gost/core/registry"
 	"github.com/go-gost/core/resolver"
@@ -47,9 +48,10 @@ var (
 	connLimiterReg    reg.Registry[conn.ConnLimiter]       = new(connLimiterRegistry)
 	rateLimiterReg    reg.Registry[rate.RateLimiter]       = new(rateLimiterRegistry)
 
-	ingressReg reg.Registry[ingress.Ingress] = new(ingressRegistry)
-	routerReg  reg.Registry[router.Router]   = new(routerRegistry)
-	sdReg      reg.Registry[sd.SD]           = new(sdRegistry)
+	ingressReg  reg.Registry[ingress.Ingress]   = new(ingressRegistry)
+	routerReg   reg.Registry[router.Router]     = new(routerRegistry)
+	sdReg       reg.Registry[sd.SD]             = new(sdRegistry)
+	observerReg reg.Registry[observer.Observer] = new(observerRegistry)
 
 	loggerReg reg.Registry[logger.Logger] = new(loggerRegistry)
 )
@@ -179,6 +181,10 @@ func SDRegistry() reg.Registry[sd.SD] {
 	return sdReg
 }
 
+func ObserverRegistry() reg.Registry[observer.Observer] {
+	return observerReg
+}
+
 func LoggerRegistry() reg.Registry[logger.Logger] {
 	return loggerReg
 }