初始提交：OCI 面板后端（含 GenAI 网关一期）

internal/service/usage.go

@@ -0,0 +1,91 @@
+package service
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"oci-portal/internal/oci"
+)
+
+// maxUsageWindowDays 限制流量/成本查询窗口，避免拉取超大区间。
+const maxUsageWindowDays = 366
+
+// InstanceTraffic 查询实例近 days 天的进出流量（按天聚合）。
+func (s *OciConfigService) InstanceTraffic(ctx context.Context, id uint, region, instanceID string, days int) (oci.InstanceTraffic, error) {
+	if days <= 0 {
+		days = 30
+	}
+	if days > maxUsageWindowDays {
+		return oci.InstanceTraffic{}, fmt.Errorf("instance traffic: days must be within %d", maxUsageWindowDays)
+	}
+	cred, err := s.credentialsByID(ctx, id)
+	if err != nil {
+		return oci.InstanceTraffic{}, err
+	}
+	end := time.Now().UTC().Truncate(time.Hour).Add(time.Hour)
+	return s.client.SummarizeInstanceTraffic(ctx, cred, oci.TrafficQuery{
+		Region:     region,
+		InstanceID: instanceID,
+		StartTime:  end.AddDate(0, 0, -days),
+		EndTime:    end,
+	})
+}
+
+// Costs 汇总租户成本或用量；时间缺省为最近 30 天，起止按粒度对齐。
+func (s *OciConfigService) Costs(ctx context.Context, id uint, q oci.CostQuery) ([]oci.CostItem, error) {
+	applyCostDefaults(&q)
+	if q.EndTime.Sub(q.StartTime) <= 0 {
+		return nil, fmt.Errorf("costs: endTime must be after startTime")
+	}
+	if q.EndTime.Sub(q.StartTime) > maxUsageWindowDays*24*time.Hour {
+		return nil, fmt.Errorf("costs: window must be within %d days", maxUsageWindowDays)
+	}
+	cred, err := s.credentialsByID(ctx, id)
+	if err != nil {
+		return nil, err
+	}
+	return s.client.SummarizeCosts(ctx, cred, q)
+}
+
+// applyCostDefaults 填充缺省值并把时间对齐到粒度边界（Usage API 要求）。
+func applyCostDefaults(q *oci.CostQuery) {
+	if q.Granularity == "" {
+		q.Granularity = "DAILY"
+	}
+	if q.QueryType == "" {
+		q.QueryType = "COST"
+	}
+	if q.GroupBy == "" {
+		q.GroupBy = "service"
+	}
+	now := time.Now().UTC()
+	if q.EndTime.IsZero() {
+		q.EndTime = now
+	}
+	if q.StartTime.IsZero() {
+		q.StartTime = q.EndTime.AddDate(0, 0, -30)
+	}
+	q.StartTime = alignDown(q.StartTime, q.Granularity)
+	// endTime 为开区间，向上对齐到粒度边界以覆盖当天/当月
+	q.EndTime = alignUp(q.EndTime, q.Granularity)
+}
+
+func alignDown(t time.Time, granularity string) time.Time {
+	t = t.UTC()
+	if granularity == "MONTHLY" {
+		return time.Date(t.Year(), t.Month(), 1, 0, 0, 0, 0, time.UTC)
+	}
+	return t.Truncate(24 * time.Hour)
+}
+
+func alignUp(t time.Time, granularity string) time.Time {
+	down := alignDown(t, granularity)
+	if down.Equal(t.UTC()) {
+		return down
+	}
+	if granularity == "MONTHLY" {
+		return down.AddDate(0, 1, 0)
+	}
+	return down.AddDate(0, 0, 1)
+}