perf(admin): optimize large-dataset loading for dashboard/users/accounts/ops

backend/internal/handler/admin/ops_snapshot_v2_handler.go

@@ -0,0 +1,145 @@
+package admin
+
+import (
+	"encoding/json"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/Wei-Shaw/sub2api/internal/pkg/response"
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+	"golang.org/x/sync/errgroup"
+)
+
+var opsDashboardSnapshotV2Cache = newSnapshotCache(30 * time.Second)
+
+type opsDashboardSnapshotV2Response struct {
+	GeneratedAt string `json:"generated_at"`
+
+	Overview        *service.OpsDashboardOverview       `json:"overview"`
+	ThroughputTrend *service.OpsThroughputTrendResponse `json:"throughput_trend"`
+	ErrorTrend      *service.OpsErrorTrendResponse      `json:"error_trend"`
+}
+
+type opsDashboardSnapshotV2CacheKey struct {
+	StartTime    string               `json:"start_time"`
+	EndTime      string               `json:"end_time"`
+	Platform     string               `json:"platform"`
+	GroupID      *int64               `json:"group_id"`
+	QueryMode    service.OpsQueryMode `json:"mode"`
+	BucketSecond int                  `json:"bucket_second"`
+}
+
+// GetDashboardSnapshotV2 returns ops dashboard core snapshot in one request.
+// GET /api/v1/admin/ops/dashboard/snapshot-v2
+func (h *OpsHandler) GetDashboardSnapshotV2(c *gin.Context) {
+	if h.opsService == nil {
+		response.Error(c, http.StatusServiceUnavailable, "Ops service not available")
+		return
+	}
+	if err := h.opsService.RequireMonitoringEnabled(c.Request.Context()); err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+
+	startTime, endTime, err := parseOpsTimeRange(c, "1h")
+	if err != nil {
+		response.BadRequest(c, err.Error())
+		return
+	}
+
+	filter := &service.OpsDashboardFilter{
+		StartTime: startTime,
+		EndTime:   endTime,
+		Platform:  strings.TrimSpace(c.Query("platform")),
+		QueryMode: parseOpsQueryMode(c),
+	}
+	if v := strings.TrimSpace(c.Query("group_id")); v != "" {
+		id, err := strconv.ParseInt(v, 10, 64)
+		if err != nil || id <= 0 {
+			response.BadRequest(c, "Invalid group_id")
+			return
+		}
+		filter.GroupID = &id
+	}
+	bucketSeconds := pickThroughputBucketSeconds(endTime.Sub(startTime))
+
+	keyRaw, _ := json.Marshal(opsDashboardSnapshotV2CacheKey{
+		StartTime:    startTime.UTC().Format(time.RFC3339),
+		EndTime:      endTime.UTC().Format(time.RFC3339),
+		Platform:     filter.Platform,
+		GroupID:      filter.GroupID,
+		QueryMode:    filter.QueryMode,
+		BucketSecond: bucketSeconds,
+	})
+	cacheKey := string(keyRaw)
+
+	if cached, ok := opsDashboardSnapshotV2Cache.Get(cacheKey); ok {
+		if cached.ETag != "" {
+			c.Header("ETag", cached.ETag)
+			c.Header("Vary", "If-None-Match")
+			if ifNoneMatchMatched(c.GetHeader("If-None-Match"), cached.ETag) {
+				c.Status(http.StatusNotModified)
+				return
+			}
+		}
+		c.Header("X-Snapshot-Cache", "hit")
+		response.Success(c, cached.Payload)
+		return
+	}
+
+	var (
+		overview *service.OpsDashboardOverview
+		trend    *service.OpsThroughputTrendResponse
+		errTrend *service.OpsErrorTrendResponse
+	)
+	g, gctx := errgroup.WithContext(c.Request.Context())
+	g.Go(func() error {
+		f := *filter
+		result, err := h.opsService.GetDashboardOverview(gctx, &f)
+		if err != nil {
+			return err
+		}
+		overview = result
+		return nil
+	})
+	g.Go(func() error {
+		f := *filter
+		result, err := h.opsService.GetThroughputTrend(gctx, &f, bucketSeconds)
+		if err != nil {
+			return err
+		}
+		trend = result
+		return nil
+	})
+	g.Go(func() error {
+		f := *filter
+		result, err := h.opsService.GetErrorTrend(gctx, &f, bucketSeconds)
+		if err != nil {
+			return err
+		}
+		errTrend = result
+		return nil
+	})
+	if err := g.Wait(); err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+
+	resp := &opsDashboardSnapshotV2Response{
+		GeneratedAt:     time.Now().UTC().Format(time.RFC3339),
+		Overview:        overview,
+		ThroughputTrend: trend,
+		ErrorTrend:      errTrend,
+	}
+
+	cached := opsDashboardSnapshotV2Cache.Set(cacheKey, resp)
+	if cached.ETag != "" {
+		c.Header("ETag", cached.ETag)
+		c.Header("Vary", "If-None-Match")
+	}
+	c.Header("X-Snapshot-Cache", "miss")
+	response.Success(c, resp)
+}