public async Task <CompositionsListViewModel> Handle(CompositionsByAlbumQuery request, CancellationToken cancellationToken)
{
var result = await _composititionService.GetCompositionsByAlbumIdAsync(request.AlbumId);
return(new CompositionsListViewModel
{
Count = result.Count,
Compositions = result.Select(c => _mapper.Map <CompositionViewModel>(c)).ToList()
});
}