refactor(metrics): Introduce JSON-friendly metrics serialization

- Create PathMetricsJSON struct for clean JSON serialization
- Add ToJSON method to convert PathMetrics to JSON-compatible representation
- Update metrics handlers and collectors to use new JSON-friendly type
- Simplify type conversion in SafePathMetrics utility function
- Improve metrics data transfer and serialization consistency

internal/handler/metrics.go

@@ -29,12 +29,12 @@ type Metrics struct {
 	RequestsPerSecond   float64 `json:"requests_per_second"`
 
 	// 新增字段
-	TotalBytes      int64                `json:"total_bytes"`
-	BytesPerSecond  float64              `json:"bytes_per_second"`
-	StatusCodeStats map[string]int64     `json:"status_code_stats"`
-	TopPaths        []models.PathMetrics `json:"top_paths"`
-	RecentRequests  []models.RequestLog  `json:"recent_requests"`
-	TopReferers     []models.PathMetrics `json:"top_referers"`
+	TotalBytes      int64                    `json:"total_bytes"`
+	BytesPerSecond  float64                  `json:"bytes_per_second"`
+	StatusCodeStats map[string]int64         `json:"status_code_stats"`
+	TopPaths        []models.PathMetricsJSON `json:"top_paths"`
+	RecentRequests  []models.RequestLog      `json:"recent_requests"`
+	TopReferers     []models.PathMetricsJSON `json:"top_referers"`
 }
 
 // MetricsHandler 处理指标请求

internal/metrics/collector.go

@@ -265,20 +265,9 @@ func (c *Collector) GetStats() map[string]interface{} {
 	}
 
 	// 转换为值切片
-	pathMetricsValues := make([]models.PathMetrics, len(pathMetrics))
+	pathMetricsValues := make([]models.PathMetricsJSON, len(pathMetrics))
 	for i, metric := range pathMetrics {
-		pathMetricsValues[i] = models.PathMetrics{
-			Path:             metric.Path,
-			AvgLatency:       metric.AvgLatency,
-			RequestCount:     atomic.Int64{},
-			ErrorCount:       atomic.Int64{},
-			TotalLatency:     atomic.Int64{},
-			BytesTransferred: atomic.Int64{},
-		}
-		pathMetricsValues[i].RequestCount.Store(metric.RequestCount.Load())
-		pathMetricsValues[i].ErrorCount.Store(metric.ErrorCount.Load())
-		pathMetricsValues[i].TotalLatency.Store(metric.TotalLatency.Load())
-		pathMetricsValues[i].BytesTransferred.Store(metric.BytesTransferred.Load())
+		pathMetricsValues[i] = metric.ToJSON()
 	}
 
 	// 收集延迟分布

internal/models/metrics.go

@@ -21,6 +21,15 @@ type PathMetrics struct {
 	AvgLatency       string       `json:"avg_latency"`
 }
 
+// PathMetricsJSON 用于 JSON 序列化的路径统计信息
+type PathMetricsJSON struct {
+	Path             string `json:"path"`
+	RequestCount     int64  `json:"request_count"`
+	ErrorCount       int64  `json:"error_count"`
+	BytesTransferred int64  `json:"bytes_transferred"`
+	AvgLatency       string `json:"avg_latency"`
+}
+
 // GetRequestCount 获取请求数
 func (p *PathMetrics) GetRequestCount() int64 {
 	return p.RequestCount.Load()
@@ -61,6 +70,17 @@ func (p *PathMetrics) AddBytes(bytes int64) {
 	p.BytesTransferred.Add(bytes)
 }
 
+// ToJSON 转换为 JSON 友好的结构
+func (p *PathMetrics) ToJSON() PathMetricsJSON {
+	return PathMetricsJSON{
+		Path:             p.Path,
+		RequestCount:     p.RequestCount.Load(),
+		ErrorCount:       p.ErrorCount.Load(),
+		BytesTransferred: p.BytesTransferred.Load(),
+		AvgLatency:       p.AvgLatency,
+	}
+}
+
 type HistoricalMetrics struct {
 	Timestamp     string  `json:"timestamp"`
 	TotalRequests int64   `json:"total_requests"`

internal/models/utils.go

@@ -1,9 +1,5 @@
 package models
 
-import (
-	"sync/atomic"
-)
-
 // SafeStatusCodeStats 安全地将 interface{} 转换为状态码统计
 func SafeStatusCodeStats(v interface{}) map[string]int64 {
 	if v == nil {
@@ -16,32 +12,21 @@ func SafeStatusCodeStats(v interface{}) map[string]int64 {
 }
 
 // SafePathMetrics 安全地将 interface{} 转换为路径指标
-func SafePathMetrics(v interface{}) []PathMetrics {
+func SafePathMetrics(v interface{}) []PathMetricsJSON {
 	if v == nil {
-		return []PathMetrics{}
+		return []PathMetricsJSON{}
 	}
-	if m, ok := v.([]PathMetrics); ok {
+	if m, ok := v.([]PathMetricsJSON); ok {
 		return m
 	}
 	if m, ok := v.([]*PathMetrics); ok {
-		result := make([]PathMetrics, len(m))
+		result := make([]PathMetricsJSON, len(m))
 		for i, metric := range m {
-			result[i] = PathMetrics{
-				Path:             metric.Path,
-				AvgLatency:       metric.AvgLatency,
-				RequestCount:     atomic.Int64{},
-				ErrorCount:       atomic.Int64{},
-				TotalLatency:     atomic.Int64{},
-				BytesTransferred: atomic.Int64{},
-			}
-			result[i].RequestCount.Store(metric.RequestCount.Load())
-			result[i].ErrorCount.Store(metric.ErrorCount.Load())
-			result[i].TotalLatency.Store(metric.TotalLatency.Load())
-			result[i].BytesTransferred.Store(metric.BytesTransferred.Load())
+			result[i] = metric.ToJSON()
 		}
 		return result
 	}
-	return []PathMetrics{}
+	return []PathMetricsJSON{}
 }
 
 // SafeRequestLogs 安全地将 interface{} 转换为请求日志