How to fix JsonException error when getting data in api controller from EntityFramework database?

Question

ASP.NET

When requesting from the database through EntityFramework on asp core (net platfrom 5), an error occurs:

JsonException: A possible object cycle was detected. This can either be due to a cycle or if the object depth is larger than the maximum allowed depth of 32. Consider using ReferenceHandler.Preserve on JsonSerializerOptions to support cycles.

Data is taken from models:
list of products

public class Good
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public string Article { get; set; }
        public string BarCode { get; set; }
        public Units Unit { get; set; }
        public decimal Price { get; set; }
        public List<GoodPrice> GoodPrices { get; set; }
        public List<CheckGood> CheckGoods { get; set; }
    }

price list

public class GoodPrice
    {
        public int Id { get; set; }
        public int GoodId { get; set; }
        public Good Good { get; set; }
        public int ShopId { get; set; }
        public Shop Shop { get; set; }
        public decimal Price { get; set; }
    }

The api controller itself and the Get method that throws an error

[Route("api/[controller]")]
    [ApiController]
    public class GoodsSynchController : ControllerBase
    {
        public IConfiguration configuration;
        public ILogger<GoodsSynchController> logger;
        public shopContext db;
        public GoodsSynchController(IConfiguration configuration, ILogger<GoodsSynchController> logger, shopContext db)
        {
            this.configuration = configuration;
            this.logger = logger;
            this.db = db;
        }
        [HttpGet("{idShop:int}")]
        public async Task<IActionResult> Get(int idShop)
            => Ok(await db.Goods.Include(g => g.GoodPrices.Where(p => p.ShopId == idShop)).ToListAsync());
    }

Please help fix this error!

Answer 1

services.AddMvc.AddJsonOptions(o => {
o.JsonSerializerOptions.ReferenceHandler = ReferenceHandler.Preserve;
o.JsonSerializerOptions.MaxDepth = 0;
})