优化后台高频查询性能

backend/internal/modules/adminfinance/dashboard_cache.go

@@ -0,0 +1,41 @@
+package adminfinance
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+const dashboardCacheTTL = time.Minute
+
+func (r *Repository) dashboardCacheKey(query DashboardQuery) string {
+	return fmt.Sprintf("admin-finance:dashboard:v1:%d:%d", query.StartDate.Unix(), query.EndDate.Unix())
+}
+
+func (r *Repository) loadDashboardCache(ctx context.Context, query DashboardQuery) *DashboardDTO {
+	if r.redis == nil {
+		return nil
+	}
+	raw, err := r.redis.Get(ctx, r.dashboardCacheKey(query)).Bytes()
+	if err != nil {
+		return nil
+	}
+	var value DashboardDTO
+	if err := json.Unmarshal(raw, &value); err != nil {
+		return nil
+	}
+	return &value
+}
+
+func (r *Repository) storeDashboardCache(ctx context.Context, query DashboardQuery, value *DashboardDTO) {
+	if r.redis == nil || value == nil {
+		return
+	}
+	raw, err := json.Marshal(value)
+	if err != nil {
+		return
+	}
+	// 缓存不可用时静默降级到实时统计，不能影响财务页面可用性。
+	_ = r.redis.Set(ctx, r.dashboardCacheKey(query), raw, dashboardCacheTTL).Err()
+}