feat: add flag to disable template insights (coder#20940)

Closes coder#20399 

To summarize the original commit messages:

- Do not log stats to the database.
- Return errors on the insight endpoints.
- Update the frontend to show those errors.
- Also fixes an issue with getting the user status count via codersdk,
since I added a test to ensure it was not disabled by this flag and it
was sending the wrong payload.

Author: code-asher

cli/testdata/coder_server_--help.golden

@@ -277,6 +277,16 @@ INTROSPECTION / PROMETHEUS OPTIONS:
       --prometheus-enable bool, $CODER_PROMETHEUS_ENABLE
           Serve prometheus metrics on the address defined by prometheus address.
 
+INTROSPECTION / TEMPLATE INSIGHTS OPTIONS: 
+      --template-insights-enable bool, $CODER_TEMPLATE_INSIGHTS_ENABLE (default: true)
+          Enable the collection and display of template insights along with the
+          associated API endpoints. This will also enable aggregating these
+          insights into daily active users, application usage, and transmission
+          rates for overall deployment stats. When disabled, these values will
+          be zero, which will also affect what the bottom deployment overview
+          bar displays. Disabling will also prevent Prometheus collection of
+          these values.
+
 INTROSPECTION / TRACING OPTIONS: 
       --trace-logs bool, $CODER_TRACE_LOGS
           Enables capturing of logs as events in traces. This is useful for

cli/testdata/server-config.yaml.golden

@@ -191,6 +191,15 @@ autobuildPollInterval: 1m0s
 # (default: 1m0s, type: duration)
 jobHangDetectorInterval: 1m0s
 introspection:
+  templateInsights:
+    # Enable the collection and display of template insights along with the associated
+    # API endpoints. This will also enable aggregating these insights into daily
+    # active users, application usage, and transmission rates for overall deployment
+    # stats. When disabled, these values will be zero, which will also affect what the
+    # bottom deployment overview bar displays. Disabling will also prevent Prometheus
+    # collection of these values.
+    # (default: true, type: bool)
+    enable: true
   prometheus:
     # Serve prometheus metrics on the address defined by prometheus address.
     # (default: <unset>, type: bool)

coderd/agentapi/stats_test.go

@@ -28,7 +28,7 @@ import (
 	"github.com/coder/coder/v2/testutil"
 )
 
-func TestUpdateStates(t *testing.T) {
+func TestUpdateStats(t *testing.T) {
 	t.Parallel()
 
 	var (
@@ -542,6 +542,135 @@ func TestUpdateStates(t *testing.T) {
 		}
 		require.True(t, updateAgentMetricsFnCalled)
 	})
+
+	t.Run("DropStats", func(t *testing.T) {
+		t.Parallel()
+
+		var (
+			now = dbtime.Now()
+			dbM = dbmock.NewMockStore(gomock.NewController(t))
+			ps  = pubsub.NewInMemory()
+
+			templateScheduleStore = schedule.MockTemplateScheduleStore{
+				GetFn: func(context.Context, database.Store, uuid.UUID) (schedule.TemplateScheduleOptions, error) {
+					panic("should not be called")
+				},
+				SetFn: func(context.Context, database.Store, database.Template, schedule.TemplateScheduleOptions) (database.Template, error) {
+					panic("not implemented")
+				},
+			}
+			updateAgentMetricsFnCalled = false
+			tickCh                     = make(chan time.Time)
+			flushCh                    = make(chan int, 1)
+			wut                        = workspacestats.NewTracker(dbM,
+				workspacestats.TrackerWithTickFlush(tickCh, flushCh),
+			)
+
+			req = &agentproto.UpdateStatsRequest{
+				Stats: &agentproto.Stats{
+					ConnectionsByProto: map[string]int64{
+						"tcp":  1,
+						"dean": 2,
+					},
+					ConnectionCount:             3,
+					ConnectionMedianLatencyMs:   23,
+					RxPackets:                   120,
+					RxBytes:                     1000,
+					TxPackets:                   130,
+					TxBytes:                     2000,
+					SessionCountVscode:          1,
+					SessionCountJetbrains:       2,
+					SessionCountReconnectingPty: 3,
+					SessionCountSsh:             4,
+					Metrics: []*agentproto.Stats_Metric{
+						{
+							Name:  "awesome metric",
+							Value: 42,
+						},
+						{
+							Name:  "uncool metric",
+							Value: 0,
+						},
+					},
+				},
+			}
+		)
+		api := agentapi.StatsAPI{
+			AgentFn: func(context.Context) (database.WorkspaceAgent, error) {
+				return agent, nil
+			},
+			Workspace: &workspaceAsCacheFields,
+			Database:  dbM,
+			StatsReporter: workspacestats.NewReporter(workspacestats.ReporterOptions{
+				Database:              dbM,
+				Pubsub:                ps,
+				StatsBatcher:          nil, // Should not be called.
+				UsageTracker:          wut,
+				TemplateScheduleStore: templateScheduleStorePtr(templateScheduleStore),
+				UpdateAgentMetricsFn: func(ctx context.Context, labels prometheusmetrics.AgentMetricLabels, metrics []*agentproto.Stats_Metric) {
+					updateAgentMetricsFnCalled = true
+					assert.Equal(t, prometheusmetrics.AgentMetricLabels{
+						Username:      user.Username,
+						WorkspaceName: workspace.Name,
+						AgentName:     agent.Name,
+						TemplateName:  template.Name,
+					}, labels)
+					assert.Equal(t, req.Stats.Metrics, metrics)
+				},
+				DisableDatabaseInserts: true,
+			}),
+			AgentStatsRefreshInterval: 10 * time.Second,
+			TimeNowFn: func() time.Time {
+				return now
+			},
+		}
+		defer wut.Close()
+
+		// We expect an activity bump because ConnectionCount > 0.
+		dbM.EXPECT().ActivityBumpWorkspace(gomock.Any(), database.ActivityBumpWorkspaceParams{
+			WorkspaceID:   workspace.ID,
+			NextAutostart: time.Time{}.UTC(),
+		}).Return(nil)
+
+		// Workspace last used at gets bumped.
+		dbM.EXPECT().BatchUpdateWorkspaceLastUsedAt(gomock.Any(), database.BatchUpdateWorkspaceLastUsedAtParams{
+			IDs:        []uuid.UUID{workspace.ID},
+			LastUsedAt: now,
+		}).Return(nil)
+
+		// Ensure that pubsub notifications are sent.
+		notifyDescription := make(chan struct{})
+		ps.SubscribeWithErr(wspubsub.WorkspaceEventChannel(workspace.OwnerID),
+			wspubsub.HandleWorkspaceEvent(
+				func(_ context.Context, e wspubsub.WorkspaceEvent, err error) {
+					if err != nil {
+						return
+					}
+					if e.Kind == wspubsub.WorkspaceEventKindStatsUpdate && e.WorkspaceID == workspace.ID {
+						go func() {
+							notifyDescription <- struct{}{}
+						}()
+					}
+				}))
+
+		resp, err := api.UpdateStats(context.Background(), req)
+		require.NoError(t, err)
+		require.Equal(t, &agentproto.UpdateStatsResponse{
+			ReportInterval: durationpb.New(10 * time.Second),
+		}, resp)
+
+		tickCh <- now
+		count := <-flushCh
+		require.Equal(t, 1, count, "expected one flush with one id")
+
+		ctx := testutil.Context(t, testutil.WaitShort)
+		select {
+		case <-ctx.Done():
+			t.Error("timed out while waiting for pubsub notification")
+		case <-notifyDescription:
+		}
+		require.True(t, updateAgentMetricsFnCalled)
+	})
 }
 
 func templateScheduleStorePtr(store schedule.TemplateScheduleStore) *atomic.Pointer[schedule.TemplateScheduleStore] {

coderd/apidoc/docs.go

@@ -768,14 +768,15 @@ func New(options *Options) *API {
 	}
 
 	api.statsReporter = workspacestats.NewReporter(workspacestats.ReporterOptions{
-		Database:              options.Database,
-		Logger:                options.Logger.Named("workspacestats"),
-		Pubsub:                options.Pubsub,
-		TemplateScheduleStore: options.TemplateScheduleStore,
-		StatsBatcher:          options.StatsBatcher,
-		UsageTracker:          options.WorkspaceUsageTracker,
-		UpdateAgentMetricsFn:  options.UpdateAgentMetrics,
-		AppStatBatchSize:      workspaceapps.DefaultStatsDBReporterBatchSize,
+		Database:               options.Database,
+		Logger:                 options.Logger.Named("workspacestats"),
+		Pubsub:                 options.Pubsub,
+		TemplateScheduleStore:  options.TemplateScheduleStore,
+		StatsBatcher:           options.StatsBatcher,
+		UsageTracker:           options.WorkspaceUsageTracker,
+		UpdateAgentMetricsFn:   options.UpdateAgentMetrics,
+		AppStatBatchSize:       workspaceapps.DefaultStatsDBReporterBatchSize,
+		DisableDatabaseInserts: !options.DeploymentValues.TemplateInsights.Enable.Value(),
 	})
 	workspaceAppsLogger := options.Logger.Named("workspaceapps")
 	if options.WorkspaceAppsStatsCollectorOptions.Logger == nil {
@@ -1528,11 +1529,28 @@ func New(options *Options) *API {
 		})
 		r.Route("/insights", func(r chi.Router) {
 			r.Use(apiKeyMiddleware)
-			r.Get("/daus", api.deploymentDAUs)
-			r.Get("/user-activity", api.insightsUserActivity)
+			r.Group(func(r chi.Router) {
+				r.Use(
+					func(next http.Handler) http.Handler {
+						return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+							if !options.DeploymentValues.TemplateInsights.Enable.Value() {
+								httpapi.Write(context.Background(), rw, http.StatusNotFound, codersdk.Response{
+									Message: "Not Found.",
+									Detail:  "Template insights are disabled.",
+								})
+								return
+							}
+
+							next.ServeHTTP(rw, r)
+						})
+					},
+				)
+				r.Get("/daus", api.deploymentDAUs)
+				r.Get("/user-activity", api.insightsUserActivity)
+				r.Get("/user-latency", api.insightsUserLatency)
+				r.Get("/templates", api.insightsTemplates)
+			})
 			r.Get("/user-status-counts", api.insightsUserStatusCounts)
-			r.Get("/user-latency", api.insightsUserLatency)
-			r.Get("/templates", api.insightsTemplates)
 		})
 		r.Route("/debug", func(r chi.Router) {
 			r.Use(