Web Api (MVC 6) Chunked body did not terminate properly with 0-sized chunk

asp.net-core-mvc asp.net-mvc asp.net-web-api c# entity-framework-core

Question

I am using MVC 6 rc1 with EF 7 rc 1 Code First Model to retrieve data over web api controller. I have 3 tables similar to below.

class Product
{
    public int Id { get; set; }
    public string SomeProperty { get; set; }
    public virtual ICollection<Categorization> Categorizations { get; set; }
    public DateTime SomeProperty2 { get; set; }
    public string SomeProperty3 { get; set; }
    public string SomeProperty4 { get; set; }

}

// NOTE: Entity key should be (ProductId, CategoryId)
class Categorization
{
    public int ProductId { get; set; }
    public Product Product { get; set; }

    public int CategoryId { get; set; }
    public Category Category { get; set; }
}

class Category
{
    public int Id { get; set; }
    public ICollection<Categorization> Categorizations { get; set; }
}

My Controller:

[ActionName("searchProducts")]
        public IEnumerable<Product> searchProducts(string searchText,int? id)
        {
          var ret= db.Products
                .Include(s => s.Categorizations).Take(2).ToList();
          return ret;
        }

Below is my Startup.cs ConfigureServices section.

          services.AddMvc()
                .AddJsonOptions(options=>
                {
                    options.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
                    options.SerializerSettings.MissingMemberHandling = Newtonsoft.Json.MissingMemberHandling.Ignore;
                });
            services.AddCors();

            var connectionString = Configuration.GetSection("Data:DefaultConnection:ConnectionString").Value;

            services.AddEntityFramework()
                .AddSqlServer()
                .AddDbContext<ContractsContext>(options => options.UseSqlServer(connectionString));


            services.AddSingleton(_ => Configuration);
            services.AddSingleton<IContractRepository, ContractRepository>();

When I call the api, I get the error as "Chunked body did not terminate properly with 0-sized chunk" in Fiddler. In fiddler resultset, I see only the first object of expected result set with properties until Categorizations filled and NO properties and remaining objects after that (Incomplete JSON data). If I do not include Categorizations in the result set, it works perfectly fine. Am I missing something? Note: EF is returning data correctly but it's getting chunked in the api call and client is unable to read the data in complete.

Popular Answer

Found the issue. Self referencing loop detected for property 'Product' with type 'Product'. Path '[0].Categorizations[0]'.

So, EF fills out both Categorization collection in Product object and also Product object in Categorization. So, while serializing to json it became a infinite loop, like:

Product>Categorizations(eachCategorization - Product>Categorizations(eachCategorization - Product>Categorizations(eachCategorization - Product>Categorizations(....

Solution: Change Startup.cs ConfigureServices section as below

services.AddMvc()
                .AddJsonOptions(options =>
                {
                    options.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;
                });


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