draft

backend/internal/api/middleware/trace.go

@@ -0,0 +1,23 @@
+package middleware
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+
+	"github.com/gin-gonic/gin"
+)
+
+// Trace 注入 trace_id 中间件
+func Trace() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		traceID := c.GetHeader("X-Trace-Id")
+		if traceID == "" {
+			b := make([]byte, 8)
+			_, _ = rand.Read(b)
+			traceID = hex.EncodeToString(b)
+		}
+		c.Set("trace_id", traceID)
+		c.Header("X-Trace-Id", traceID)
+		c.Next()
+	}
+}