feat: add prometheus metrics without external standalone exporter

repositories/heartbeart.go

@@ -26,6 +26,16 @@ func (r *HeartbeatRepository) InsertBatch(heartbeats []*models.Heartbeat) error
 	return nil
 }
 
+func (r *HeartbeatRepository) Count() (int64, error) {
+	var count int64
+	if err := r.db.
+		Model(&models.Heartbeat{}).
+		Count(&count).Error; err != nil {
+		return 0, err
+	}
+	return count, nil
+}
+
 func (r *HeartbeatRepository) CountByUser(user *models.User) (int64, error) {
 	var count int64
 	if err := r.db.

repositories/repositories.go

@@ -17,6 +17,7 @@ type IAliasRepository interface {
 
 type IHeartbeatRepository interface {
 	InsertBatch([]*models.Heartbeat) error
+	Count() (int64, error)
 	CountByUser(*models.User) (int64, error)
 	GetAllWithin(time.Time, time.Time, *models.User) ([]*models.Heartbeat, error)
 	GetFirstByUsers() ([]*models.TimeByUser, error)