public async Task <bool> Handle(DeleteStudentCommand request, CancellationToken cancellationToken)
            {
                Student entity;

                entity = await _context.Students.FindAsync(request.Id.Value);

                entity.IsDeleted = 1;

                await _context.SaveChangesAsync(cancellationToken);

                return(true);
            }
            public async Task <Guid> Handle(UpsertStudentCommand request, CancellationToken cancellationToken)
            {
                Student entity;

                if (request.Id.HasValue)
                {
                    // Update command.
                    entity = await _context.Students.FindAsync(request.Id.Value);
                }
                else
                {
                    entity = new Student();
                    _context.Students.Add(entity);

                    entity.IsDeleted = 0;
                }

                entity.Name  = request.Name;
                entity.Email = request.Email;

                await _context.SaveChangesAsync(cancellationToken);

                return(entity.Id);
            }