Fat Controllers: How Can I Make It Thin?

I am developing a blog engine using EF 6 and MVC 5.

I chose not to use the repository pattern or UoW ​​as it is already implemented in EF 6 at the infrastructure level.

The solution contains the following layers.

DataModels Level: It has simple POCOs that are auto-generated and dbContext.

public partial class Article
    {
        public int Id { get; set; }
        public string Slug { get; set; }
        public string Title { get; set; }
        public string PostBody { get; set; }
        public System.DateTime CreatedOn { get; set; }
        public bool IsPublished { get; set; }
        public string Author { get; set; }
    }

      

        
        
        
      

    

Service level:

public interface IBlogEngine
    {
        List<Article> GetFrontPageBlogPosts();
        void SaveArticle(Article article);
        List<Article> GetArticlesByStatus(string isPublished);
        Article GetBySlug(string slug);
        Article GetById(int id);
        bool Exists(string slugUrl);
        void Delete(int id);
    }

      

        
        
        
      

    

IBlogEngine

... Some methods have been omitted for brevity.

public class BlogEngine : IBlogEngine
    {
        private readonly dbContext _context;

        public BlogEngine(DbContext context)
        {
            _context = context;
        }


        public void SaveArticle(Article article)
        {
            if (article.Id == 0)
            {
                _context.Articles.Add(article);
            }
            else
            {
                _context.Entry(article).State = EntityState.Modified;
            }

            _context.SaveChanges();
        }



        public Article GetBySlug(string slug)
        {
            return _context.Articles.SingleOrDefault(x => x.Slug == slug.Trim());
        }


    }

      

        
        
        
      

    

User interface level

 public class ArticleController : Controller
    {
        private readonly IBlogEngine _engine;
        public ArticleController(IBlogEngine engine)
        {
            _engine = engine;
        }

        [HttpGet]
        public ActionResult Edit(string slug)
        {
            if (string.IsNullOrWhiteSpace(slug))
            {
                return HttpNotFound();
            }

            var article = _engine.GetBySlug(slug);

            if (article == null)
            {
                return HttpNotFound();
            }

            var model = new EditViewModel { Id = article.Id, Slug = article.Slug, 
            Title = article.Title, PostBody = article.PostBody, IsPublished = true };

            return View("Create", model);
        }

        [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult Edit(EditViewModel blogPost)
        {
            if (!ModelState.IsValid)
            {
                return View("Create", blogPost);
            }
            // Get Article by Id
            var article = _engine.GetById(blogPost.Id);

            if (article == null)
            {
                return HttpNotFound();
            }

            // Update it
            article.Id = blogPost.Id;
            article.Title = blogPost.Title.Trim();
            article.Slug = blogPost.Slug.ToUrlSlug();
            article.PostBody = blogPost.PostBody;
            article.CreatedOn = DateTime.UtcNow;
            article.IsPublished = blogPost.IsPublished;
            article.Author = User.Identity.Name;

            // Save it
            _engine.SaveArticle(article);

            return RedirectToAction("Create", "Article");
        }

    }

      

        
        
        
      

    

Problem Consider a scenario where a user has finished editing their old blog post / article and clicked the submit button to update the blog post / article.

Is my HTTP POST Change Action Too Fat? I feel like the controller is doing something here too.

• Get an existing article from the database

• Update it with ViewModel values

• Call the SaveArticle
  
  method from the service layer.

How can I put this controller on a diet?

Shouldn't the Service Layer method SaveArticle

perform the task of fetching the article from the Db and updating it with new values ​​and calling the SaveChanges method?

If the above statement is true, how do you pass the ViewModel method to the ServiceLayer method? Isn't it a bad solution to allow passing ViewModels into the service layer?

How can I handle this? I am confused and need some help.