Web api route prefixes with controller action names

Question

I have an asp.net core 3.1 application. In startup file, I have the following route.

  app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllerRoute(
                name: "default",
                pattern: "{controller}/{action}/{id?}",
                defaults: new { controller = "Home", action = "Index" });
            endpoints.MapControllers();
            endpoints.MapRazorPages();
        });

I have position controller with index and details view.

 public class PositionController : Controller
{
    private readonly IPositionRepository repository;

    public Position Position { get; set; }

    public PositionController(IPositionRepository repository)
    {
        this.repository = repository;
    }
    
    public IActionResult Index()
    {
        return View();
    }

    public async Task<IActionResult> Details(int id)
    {
        if (id < 0)
            return View();

        Position = await repository.FindPositionById(id);

        if (Position == null)
           return RedirectToAction("_NotFound");

        return View(Position);
    }

Index view points to https://localhost:44356/Position, Details view points to https://localhost:44356/Position/1. (position has id=1)

I have a web api to fetch all the positons data with Get and GetTaskGroups actions.

[Produces("application/json")]
[Route("api/positions")]
[ApiController]
public class PositionsController : Controller
{
    private readonly IPositionRepository repository;

    public PositionsController(IPositionRepository repository)
    {
        this.repository = repository;
    }

    [HttpGet]
    public async Task<IActionResult> Get()
    {
        return Json(new { data = await repository.GetPositions() },
            new JsonSerializerSettings() { MetadataPropertyHandling = MetadataPropertyHandling.Ignore 
                         });
    }

    [HttpGet("{posId}/tasks")]
    public async Task<IActionResult> GetTaskGroups(int posId)
    {
        return Json(new { data = await repository.GetTaskGroups(posId) });
    }

I am fetching data with jQuery ajax calls as follows.

function loadPositions() {
positions =
    $('#positionsList').DataTable({
        "ajax": {
            "url": "api/positions",
            "type": "get",
            "datatype": "json"
        },...

function loadTaskGroups(posId) {
taskGroups =
    $('#taskGroups').DataTable({
        "ajax": {
            "url": `/api/positions/${posId}/tasks`,
            "type": "get",
            "datatype": "json"
        },...

I can fetch data for Index view, but, not for Details view. The web api route points to https://localhost:44356/Position/Details/1/api/positions/1/tasks which should point to https://localhost:44356/api/positions/1/tasks. The reason is that I fetch data for the Index view with the following route https://localhost:44356/api/positions/

I think, the problem is related to the default route. Index views does not show up in the url, but details view does.

Answer 1

Using your code, I did reproduce your problem.

You only need to delete the " / " in the ajax url in the loadTaskGroups method.

function loadTaskGroups(posId) {
taskGroups =
    $('#taskGroups').DataTable({
        "ajax": {
            "url": `api/positions/${posId}/tasks`,
            "type": "get",
            "datatype": "json"
        },...

Here is the test result:

Answer 2

try so

function loadPositions() {
positions =
    $('#positionsList').DataTable({
        "ajax": {
            "url": "/api/positions",
            "type": "get",
            "datatype": "json"
        },...