feat(playlist): add usage statisics

pkg/metrics/report_usage.go

@@ -55,6 +55,7 @@ func sendUsageStats() {
 	metrics["stats.dashboards.count"] = statsQuery.Result.DashboardCount
 	metrics["stats.users.count"] = statsQuery.Result.UserCount
 	metrics["stats.orgs.count"] = statsQuery.Result.OrgCount
+	metrics["stats.playlist.count"] = statsQuery.Result.PlaylistCount
 
 	dsStats := m.GetDataSourceStatsQuery{}
 	if err := bus.Dispatch(&dsStats); err != nil {

pkg/models/stats.go

@@ -4,6 +4,7 @@ type SystemStats struct {
 	DashboardCount int
 	UserCount      int
 	OrgCount       int
+	PlaylistCount  int
 }
 
 type DataSourceStats struct {

pkg/services/sqlstore/stats.go

 package sqlstore
 
 import (
+	"fmt"
+
 	"github.com/grafana/grafana/pkg/bus"
 	m "github.com/grafana/grafana/pkg/models"
 )
@@ -34,7 +36,11 @@ func GetSystemStats(query *m.GetSystemStatsQuery) error {
       (
         SELECT COUNT(*)
         FROM ` + dialect.Quote("dashboard") + `
-      ) AS dashboard_count
+      ) AS dashboard_count,
+      (
+        SELECT COUNT(*)
+        FROM ` + dialect.Quote("playlist") + `
+      ) AS playlist_count
 			`
 
 	var stats m.SystemStats