code: func (m *GormLabelRepository) List(ctx context.Context, spaceID uuid.UUID) ([]Label, error) {
  	defer goa.MeasureSince([]string{"goa", "db", "label", "query"}, time.Now())
  	var objs []Label
  	err := m.db.Where("space_id = ?", spaceID).Find(&objs).Error
  	if err != nil && err != gorm.ErrRecordNotFound {
  		return nil, err
  	}
  	return objs, nil
  }
docs: // List all labels in a space