.Include() Not Pulling Additional Resource - ajax

Question

I have a JS file making an AJAX request to a controller. The code below works without the .Include() method but when I add it, the app runs but it doesn't populate my code. I tried running in debug mode but I'm not getting clear answers.
JS file
$(function () {
$.ajax({
type: "GET",
url: "https://localhost:5001/api/SortData/All",
contentType: "application/json; charset=utf-8",
dataType: "json"
}).done(response => {
// For each element in the response, add the submission card
$(response).each(index => {
// Formatting the submission date to be legible
var date = getFormattedDate(response[index].submitDate);
// Adding each submission card to the dashboard
$(".proposals").append(` ...some html...`)}});
API
[Route("api/[controller]/[action]")]
public class SortDataController : ControllerBase
{
[HttpGet, ActionName("All")]
public IQueryable<Proposals> GetAllProposals()
{
return _context.Proposals.Include(p => p.DeveloperName.Name);
}
}
Proposals Model
public class Proposals
{
public Proposals()
{
// Adding values to fields automatically. These fields are not on the form for users to see and update.
SubmitDate = DateTime.Now;
StatusId = 14;
AssignedTo = "johnDoe";
}
// other properties
[NotMapped]
public Users DeveloperName { get; set; }
// a few more properties
}
Users Model
public partial class Users
{
// other properties
public string Name { get; set; }
//some more properties
public IList<Proposals> Proposals { get; set; }
}

Answer 1

The Include is for the Navigation property only, so instead of using Include(p => p.DeveloperName.Name) try to use Include(p => p.DeveloperName) which will also contains Name when you retrieve data.
return _context.Proposals.Include(p => p.DeveloperName);
If you only would like a few specific fields,you need to select them explicitly. Something like this would work:
_context.Proposals.Include(p => p.DeveloperName)
.Select(p => new Proposals
{
StatusId = p.StatusId ,
// etc... The fields you need from Proposals go here
DeveloperName = new Users
{
Name = p.Category.Name
}
}

Answer 2

OK, I figured out Blue's Clues.
Turns out, I had to add
.AddJsonOptions(options => options.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore);
to the end of services.AddMvc() in my StartUp. Apparently, there was some looping issue that this code prevents.
I also updated my API Controller to...
[Route("api/SortData")]
public class SortDataController : Controller
{
[HttpGet("All")]
public IActionResult GetAllProposals()
{
return Ok(_context.Proposals.Include(p => p.DeveloperName).Include(p => p.Status).ToList());
}
}
From there, I was able to see the JSON response in the XHR and add it accordingly to my JS file.