add Route and Selector interfaces

selector/selector.go

@@ -0,0 +1,74 @@
+package selector
+
+import (
+	"sync/atomic"
+	"time"
+
+	"github.com/go-gost/core/metadata"
+)
+
+type Selectable interface {
+	Marker() Marker
+	Metadata() metadata.Metadata
+}
+
+type Selector[T any] interface {
+	Select(...T) T
+}
+
+type Strategy[T Selectable] interface {
+	Apply(...T) T
+}
+
+type Filter[T Selectable] interface {
+	Filter(...T) []T
+}
+
+type Marker interface {
+	Time() time.Time
+	Count() int64
+	Mark()
+	Reset()
+}
+
+type failMarker struct {
+	failTime  int64
+	failCount int64
+}
+
+func NewFailMarker() Marker {
+	return &failMarker{}
+}
+
+func (m *failMarker) Time() time.Time {
+	if m == nil {
+		return time.Time{}
+	}
+
+	return time.Unix(atomic.LoadInt64(&m.failTime), 0)
+}
+
+func (m *failMarker) Count() int64 {
+	if m == nil {
+		return 0
+	}
+
+	return atomic.LoadInt64(&m.failCount)
+}
+
+func (m *failMarker) Mark() {
+	if m == nil {
+		return
+	}
+
+	atomic.AddInt64(&m.failCount, 1)
+	atomic.StoreInt64(&m.failTime, time.Now().Unix())
+}
+
+func (m *failMarker) Reset() {
+	if m == nil {
+		return
+	}
+
+	atomic.StoreInt64(&m.failCount, 0)
+}