From cf0796c2290843faa3db005741e23d3085e4c36f Mon Sep 17 00:00:00 2001
From: nvnyale <naveen.akula@yale.edu>
Date: Tue, 25 Oct 2022 01:23:55 -0400
Subject: [PATCH] added metrics for datasync service

---
 api/handlers_metrics.go | 84 +++++++++++++++++++++++++++++++++++++++++
 api/routes.go           |  2 +
 2 files changed, 86 insertions(+)

diff --git a/api/handlers_metrics.go b/api/handlers_metrics.go
index 13471da..ffb22ed 100644
--- a/api/handlers_metrics.go
+++ b/api/handlers_metrics.go
@@ -367,6 +367,90 @@ func (s *server) GetRDSMetricsURLHandler(w http.ResponseWriter, r *http.Request)
 	w.Write(meta)
 }
 
+func (s *server) GetDataSyncMetricsURLHandler(w http.ResponseWriter, r *http.Request) {
+	w = LogWriter{w}
+	vars := mux.Vars(r)
+	account := s.mapAccountNumber(vars["account"])
+	taskId := vars["taskId"]
+
+	policy, err := defaultCloudWatchMetricsPolicy()
+	if err != nil {
+		handleError(w, err)
+		return
+	}
+
+	role := fmt.Sprintf("arn:aws:iam::%s:role/%s", account, s.session.RoleName)
+	session, err := s.assumeRole(
+		r.Context(),
+		s.session.ExternalID,
+		role,
+		policy,
+	)
+	if err != nil {
+		msg := fmt.Sprintf("failed to assume role in account: %s", account)
+		handleError(w, apierror.New(apierror.ErrForbidden, msg, nil))
+		return
+	}
+
+	cwService := cloudwatch.New(cloudwatch.WithSession(session.Session))
+
+	queries := r.URL.Query()
+	metrics := queries["metric"]
+	if len(metrics) == 0 {
+		handleError(w, apierror.New(apierror.ErrBadRequest, "at least one metric is required", nil))
+		return
+	}
+
+	req := cloudwatch.MetricsRequest{}
+	if err := parseQuery(r, req); err != nil {
+		handleError(w, apierror.New(apierror.ErrBadRequest, "failed to parse query", err))
+		return
+	}
+
+	key := fmt.Sprintf("%s/%s/%s/%s%s", account, s.org, taskId, strings.Join(metrics, "-"), req.String())
+	log.Debugf("object key: %s", key)
+
+	hashedCacheKey := s.imageCache.HashedKey(key)
+	if res, expire, ok := s.resultCache.GetWithExpiration(hashedCacheKey); ok {
+		log.Debugf("found cached object: %s", res)
+
+		if body, ok := res.([]byte); ok {
+			w.Header().Set("X-Cache-Hit", "true")
+			w.Header().Set("X-Cache-Expire", fmt.Sprintf("%0.fs", time.Until(expire).Seconds()))
+			w.Header().Set("Content-Type", "application/json")
+			w.WriteHeader(http.StatusOK)
+			w.Write(body)
+			return
+		}
+	}
+
+	cwMetrics := []cloudwatch.Metric{}
+	for _, m := range metrics {
+		cwMetrics = append(cwMetrics, cloudwatch.Metric{"AWS/DataSync", m, "TaskId", taskId})
+	}
+	req["metrics"] = cwMetrics
+
+	log.Debugf("getting metrics with request %+v", req)
+	image, err := cwService.GetMetricWidget(r.Context(), req)
+	if err != nil {
+		log.Errorf("failed getting metrics widget image: %s", err)
+		handleError(w, err)
+		return
+	}
+
+	meta, err := s.imageCache.Save(r.Context(), hashedCacheKey, image)
+	if err != nil {
+		log.Errorf("failed saving metrics widget image to cache: %s", err)
+		handleError(w, err)
+		return
+	}
+	s.resultCache.Set(hashedCacheKey, meta, 300*time.Second)
+
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	w.Write(meta)
+}
+
 func parseQuery(r *http.Request, request cloudwatch.MetricsRequest) error {
 	log.SetLevel(log.DebugLevel)
 	queries := r.URL.Query()
diff --git a/api/routes.go b/api/routes.go
index c5c7701..2cae2cd 100644
--- a/api/routes.go
+++ b/api/routes.go
@@ -39,6 +39,8 @@ func (s *server) routes() {
 	metricsApi.HandleFunc("/{account}/buckets/{bucket}/graph", s.GetS3MetricsURLHandler).Queries("metric", "{metric:(?:BucketSizeBytes|NumberOfObjects)}").Methods(http.MethodGet)
 	// metrics endpoints for RDS services
 	metricsApi.HandleFunc("/{account}/rds/{type}/{id}/graph", s.GetRDSMetricsURLHandler).Methods(http.MethodGet)
+	// metrics endpoints for DataSync services
+	metricsApi.HandleFunc("/{account}/movers/{taskId}/graph", s.GetDataSyncMetricsURLHandler).Methods(http.MethodGet)
 
 	inventoryApi := s.router.PathPrefix("/v1/inventory").Subrouter()
 	inventoryApi.HandleFunc("/ping", s.PingHandler).Methods(http.MethodGet)