6 types of code that shouldn't be inside .NET controllers

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.NET controllers should be lightweight

An ever-repeated commonplace phrase with three tons of luggage to be unpacked.

Why should they be light? What is the use of this? What steps can I take to make them easier if they are not already? How do I keep them light?

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1. (DTO)

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public IActionResult CheckOutBook([FromBody]BookRequest bookRequest)
{
    var book = new Book();

    book.Title = bookRequest.Title;
    book.Rating = bookRequest.Rating.ToString();
    book.AuthorID = bookRequest.AuthorID;

    //...
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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2.

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public IActionResult Register([FromBody]AutomobileRegistrationRequest request)
{
    // //validating that a VIN number was provided...
    if (string.IsNullOrEmpty(request.VIN))
    {
        return BadRequest();
    }
    
    //...
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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public IActionResult GetBookById(int id)
{
    try
    {
      //  ,    -...
    }
    catch (DoesNotExistException)
    {
      // -,     ...
    }
    catch (Exception e)
    {
      // ,  ...
    }
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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6. /

, (Repository), , . - CRUD, .

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public IActionResult CheckOutBook(BookRequest request)
{
    var book = _bookRepository.GetBookByTitleAndAuthor(request.Title, request.Author);
    //       ,    
    //    -  ...
    //...
    return Ok(book);
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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"C# ASP.NET Core ".

- «Serverless azure». 1: , serverless computing, serverless computing azure , azure function. 2: , azure storage, , ARM . !