public async Task <PhotoDto> Handle(AddPhotoCommand request, CancellationToken cancellationToken)
{
var user = await _userRepository.Single(
u => u.Id == request.AuthenticatedUser.Id,
cancellationToken
);
var newPhotoName = $"{Guid.NewGuid().ToString()}{Path.GetExtension(request.Photo.FileName)}";
var addPhotoRequest = new AddPhotoRequest(newPhotoName, request.Photo.OpenReadStream(), request.Photo.ContentType);
var addPhotoResponse = await _photoStorage.Add(addPhotoRequest, cancellationToken);
var photo = new Photo(newPhotoName, addPhotoResponse.Url);
user.AddPhoto(photo);
return(_mapper.Map <Photo, PhotoDto>(photo));
}