public async Task Create(CommentInputModel model, string userId)
{
var songId = model.SongId;
Comment comment = model.To <Comment>();
Song song = this.context.Songs.Find(songId);
ApplicationUser user = this.context.Users.Find(userId);
comment.UserId = userId;
comment.SongId = songId;
comment.User = user;
comment.Song = song;
await this.context.Comments.AddAsync(comment);
await this.context.SaveChangesAsync();
}