WIP

mtojek · mtojek · commit d0b839881a52 · 2023-04-13T08:39:38.000+02:00
diff --git a/cli/server.go b/cli/server.go
@@ -844,6 +844,12 @@ func (r *RootCmd) Server(newAPI func(context.Context, *coderd.Options) (*coderd.
 				}
 				defer closeWorkspacesFunc()
 
+				closeAgentStatsFunc, err := prometheusmetrics.AgentStats(ctx, logger, options.PrometheusRegistry, options.Database, 0)
+				if err != nil {
+					return xerrors.Errorf("register agent stats prometheus metric: %w", err)
+				}
+				defer closeAgentStatsFunc()
+
 				//nolint:revive
 				defer serveHandler(ctx, logger, promhttp.InstrumentMetricHandler(
 					options.PrometheusRegistry, promhttp.HandlerFor(options.PrometheusRegistry, promhttp.HandlerOpts{}),
diff --git a/coderd/prometheusmetrics/prometheusmetrics.go b/coderd/prometheusmetrics/prometheusmetrics.go
@@ -200,7 +200,7 @@ func Agents(ctx context.Context, logger slog.Logger, registerer prometheus.Regis
 			})
 			if err != nil {
 				logger.Error(ctx, "can't get workspace rows", slog.Error(err))
-				continue
+				goto done
 			}
 
 			for _, workspace := range workspaceRows {
@@ -283,9 +283,59 @@ func Agents(ctx context.Context, logger slog.Logger, registerer prometheus.Regis
 			agentsConnectionLatenciesGauge.Commit()
 			agentsAppsGauge.Commit()
 
+		done:
 			logger.Debug(ctx, "Agent metrics collection is done")
 			metricsCollectorAgents.Observe(timer.ObserveDuration().Seconds())
 		}
 	}()
 	return cancelFunc, nil
 }
+
+func AgentStats(ctx context.Context, logger slog.Logger, registerer prometheus.Registerer, db database.Store, duration time.Duration) (context.CancelFunc, error) {
+	if duration == 0 {
+		duration = 1 * time.Minute
+	}
+
+	metricsCollectorAgentStats := prometheus.NewHistogram(prometheus.HistogramOpts{
+		Namespace: "coderd",
+		Subsystem: "prometheusmetrics",
+		Name:      "agentstats_execution_seconds",
+		Help:      "Histogram for duration of agent stats metrics collection in seconds.",
+		Buckets:   []float64{0.001, 0.005, 0.010, 0.025, 0.050, 0.100, 0.500, 1, 5, 10, 30},
+	})
+	err := registerer.Register(metricsCollectorAgentStats)
+	if err != nil {
+		return nil, err
+	}
+
+	createdAfter := database.Now().Add(-duration)
+	ctx, cancelFunc := context.WithCancel(ctx)
+	ticker := time.NewTicker(duration)
+	go func() {
+		defer ticker.Stop()
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case <-ticker.C:
+			}
+
+			logger.Debug(ctx, "Agent metrics collection is starting")
+			timer := prometheus.NewTimer(metricsCollectorAgentStats)
+
+			_, err := db.GetWorkspaceAgentStats(ctx, createdAfter)
+			if err != nil {
+				logger.Error(ctx, "can't get agent stats", slog.Error(err))
+				goto done
+			}
+
+			db.GetWorkspAgents
+
+		done:
+			logger.Debug(ctx, "Agent metrics collection is done")
+			metricsCollectorAgentStats.Observe(timer.ObserveDuration().Seconds())
+		}
+	}()
+	return cancelFunc, nil
+
+}
