EntityFramework Many-to-Many serilization cycle - entity-framework

Question

I have a code first Blazor WebAssembly application in which I have a Many-to-Many relationship.
public class A
{
public A()
{
this.Bs = new HashSet<B>();
}
public int Id { get; set; }
public string Name { get; set; }
public virtual ICollection<B> Bs { get; set; }
}
public class B
{
public B()
{
this.As= new HashSet<A>();
}
public int Id { get; set; }
public string Name { get; set; }
public virtual ICollection<A> As { get; set; }
}
In my client, I call the Get method of the server AController. I would like to have in each A object, the Bs ICollection.
If the Get method is like this, the Bs collection is null :
[HttpGet]
public IEnumerable<A> Get()
{
return _context.A.ToList();
}
If it is like this, to inlude Bs, I have an exception ("System.Text.Json.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.")
[HttpGet]
public IEnumerable<A> Get()
{
return _context.A.Include(a => a.Bs).ToList();
}
So in my Startup.cs (on the server) I had the following in the ConfigureServices method
services.AddControllers().AddJsonOptions(o =>
o.JsonSerializerOptions.ReferenceHandler = ReferenceHandler.Preserve);
So now, the serialization works, but the deserialization fails because the JSON is different, not only a List of A.
In the client, I call the get method of the AController like this :
var response = await _httpClient.GetAsync("my_api_adresse");
return await response.Content.ReadFromJsonAsync<List<A>>();
But du to the ReferenceHandler.Preserve the JSON is like this, so the desirialization can't work and raises an exception :
{
"$id": "1",
"$values": [
{
"$id": "2",
"id": 4,
"name": "nameA3",
"Bs": {
"$id": "3",
"$values": [
{
"$id": "4",
"id": 1,
"Name": "NameB1",
"As": {
"$id": "5",
"$values": [
{
"$ref": "2"
}
]
}
}
]
}
}
]
}
What could I do to be able to include Bs collection into A objects and be able to serialize and deserialize the response without any trouble ?

Answer 1

Try using DTO objects (data transfer objects).
There are many ways. One is:
Create two new classes that are similar to class A and class B, but this one without a list of A objects. Instead, use a list of A Ids. That would solve your problem.
Comment gere if you need code sample