public async Task <CompositionsListViewModel> Handle(CompositionsByArtistQuery request, CancellationToken cancellationToken)
{
var result = await _compositionService.GetCompositionsByArtistIdAsync(request.ArtistId);
return(new CompositionsListViewModel
{
Count = result.Count,
Compositions = result.Select(c => _mapper.Map <CompositionViewModel>(c)).ToList()
});
}