public class CommentsController : ApiController
    {
        private ICommentService commentsService;

        public CommentsController(ICommentService commentsService)
        {
            this.commentsService = commentsService;
        }

        public IQueryable<Comment> Get()
        {
            return commentsService.GetAll();
        }

        public HttpResponseMessage Get(int id)
        {
            var comment = commentsService.GetComment(id);

            if (comment == null)
            {
                return this.Request.CreateErrorResponse(HttpStatusCode.NotFound, "Comment not found!");
            }

            return this.Request.CreateResponse(HttpStatusCode.OK, comment);
        }

        public HttpResponseMessage Post([FromBody]Comment comment)
        {
            commentsService.Add(comment);

            var message = this.Request.CreateResponse(HttpStatusCode.Created);
            message.Headers.Location = new Uri(this.Request.RequestUri + comment.CommentID.ToString(CultureInfo.InvariantCulture));

            return message;
        }

        public void Put([FromBody]Comment comment)
        {
            commentsService.Modify(comment);
        }

        public void Delete([FromBody]Comment comment)
        {
            commentsService.Remove(comment);
        }
    }