实现新的计数器算法（将时间分片， 统计更加精准）

internal/utils/counters/item.go

@@ -0,0 +1,77 @@
+// Copyright 2023 GoEdge CDN goedge.cdn@gmail.com. All rights reserved. Official site: https://goedge.cn .
+
+package counters
+
+import (
+	"github.com/TeaOSLab/EdgeNode/internal/utils/fasttime"
+)
+
+type Item struct {
+	lifeSeconds int64
+
+	spanSeconds int64
+	spans       []*Span
+
+	lastUpdateTime int64
+}
+
+func NewItem(lifeSeconds int) *Item {
+	if lifeSeconds <= 0 {
+		lifeSeconds = 60
+	}
+	var spanSeconds = lifeSeconds / 10
+	if spanSeconds < 1 {
+		spanSeconds = 1
+	}
+	var countSpans = lifeSeconds/spanSeconds + 1 /** prevent index out of bounds **/
+	var spans = []*Span{}
+	for i := 0; i < countSpans; i++ {
+		spans = append(spans, NewSpan())
+	}
+
+	return &Item{
+		lifeSeconds:    int64(lifeSeconds),
+		spanSeconds:    int64(spanSeconds),
+		spans:          spans,
+		lastUpdateTime: fasttime.Now().Unix(),
+	}
+}
+
+func (this *Item) Increase() uint64 {
+	var currentTime = fasttime.Now().Unix()
+	var spanIndex = int(currentTime % this.lifeSeconds / this.spanSeconds)
+	var span = this.spans[spanIndex]
+	var roundTime = currentTime / this.spanSeconds * this.spanSeconds
+
+	this.lastUpdateTime = currentTime
+
+	if span.Timestamp < roundTime {
+		span.Timestamp = roundTime // update time
+		span.Count = 0             // reset count
+	}
+	span.Count++
+
+	return this.Sum()
+}
+
+func (this *Item) Sum() uint64 {
+	var result uint64 = 0
+	var currentTimestamp = fasttime.Now().Unix()
+	for _, span := range this.spans {
+		if span.Timestamp >= currentTimestamp-this.lifeSeconds {
+			result += span.Count
+		}
+	}
+	return result
+}
+
+func (this *Item) Reset() {
+	for _, span := range this.spans {
+		span.Count = 0
+		span.Timestamp = 0
+	}
+}
+
+func (this *Item) IsExpired() bool {
+	return this.lastUpdateTime < fasttime.Now().Unix()-this.lifeSeconds-this.spanSeconds
+}