Which Way .NET Developer?

[vbilopav]

Which Way .NET Developer?

You must create an endpoint that will return games, joined by genre by id, from the database.

Option 1

public abstract class BaseModel
{
    public Guid Id { get; set; }
}

public class Genre : BaseModel
{
    public string Name { get; set; }
}

public class Game : BaseModel
{
    public string Name { get; set; }
    public Genre Genre { get; set; }
    public decimal Price { get; set; }
}

public interface IGameRepository
{
    Game Get(Guid id);
}

public class GameRepository : IGameRepository
{
    private  readonly DataContext _context;

    public GameRepository(DataContext context)
    {
        _context = context;
    }

    public Game? Get(Guid id)
    {
        return _context
            .Games
            .Include(g => g.Genre)
            .Where(g = g.Id == id)
            .AsNoTracking()
            .FirstOrDefault();
    }
}

public class GameDto // base DTO?
{
    public Guid Id { get; set; }
    public string Name { get; set; }
    public string Genre { get; set; } // Genre DTO?
    public decimal Price { get; set; }
}

public static class GameExtension 
{
    public static GameDto AsDto(this Game game)
    {
        return new GameDto
        {
            Id = game.Id,
            Name = game.Name,
            Genre = game.Genre.Name,
            Price = game.Price
        };
    }
}

public interface IGameService
{
    GameDto GetGameById(Guid id);
}

public class GameService : IGameService
{
    private readonly IGameRepository _repository;

    public GameService(IGameRepository repository)
    {
        _repository = repository;
    }

    public GameDto? GetGameById(Guid id)
    {
        return _repository.Get(id)?.AsDto();
}

public class GamesController : Controller
{
    private readonly IGameService _service;

    public GameController(IGameService service)
    {
        _service = service;
    }

    [HttpGet("{id}")]
    public async Task<IActionResult> Get(Guid id)
    {
        var game = _service.GetGameById(id);
        if (game == null)
        {
            return NotFound();
        }
        return Ok(result);
    }
}

Option 2

app.MapGet("/games/{id}", (DbConnection connection, HttpResponse response, Guid id) => {
    response.ContentType = MediaTypeNames.Application.Json;
    var result = connection.Read<string>(@"
        select
            json_build_object(
                'id', game_id,
                'name', games.name,
                'genre', genres.name,
                'price', price
            )
        from 
            games join genres using (genre_id)
        where
            game_id = @id
    ", id)
    .FirstOrDefault();
    if (result == null)
    {
        return Results.NotFound();
    }
    return Results.Ok(result);
});

Which way?

[SankethJain]

Option 2. Direct queries is the way to go when performing Get operations. ORM like EfCore are still quite expensive

[Salman-Sali]

Direct queries == No separation of concerns. And repository pattern is too much separation of concerns.

Option 3. CQRS with MediatR without repository pattern

[crimcol]

It is unclear what exactly you are asking.
Option 1 is good. You are using controllers and repository to retrieve the data. It is good to have a service because you are separated UI (endpoint) from your logic. It is good for the future refactoring and extension.
Option 2. You are using minimal API and everything is coded inside. You can use minimal API, but I would highly recommend still use service layer as in option 1.

CQRS and MediatR should be used only if you understand why you added that. On my opinion it slightly more complicated then services and it might be redundant.
CQRS + MediatR does not solve performance issue. It might be easier only if you always create a new class request and handler for new endpoint. But there no any problem if you have services by features and not buy object/resources. Same applies to repository.

Good luck.