ASP NET Core Minimal API always returns 200 instead of specified 204

Question

Even when I say return 204 (NoContent), it returns 200. Why?

app.MapGet("/api/alive", (context) => Task.FromResult(new StatusCodeResult(204)));

Status code in browser is 200

Marmara

Can you show more of your code please so we can see how youre getting to this response. Typically I would expect to see Return NoContent(); – Makeup

It makes no difference if you Use Results.NoContent(), new NoContentResult() or new StatusCodeResult(204) – Marmara

Did you check the documentation? Are you aware of the signature of second argument(RequestDelegate) ? Where did you get that it has a return type? – Colner

Changing the type to RequestDelegate did the trick – Marmara

Do not edit the answer into your question. I have rolled back your question to the original version. – Ingres

ok, didn't know it would be a problem. – Marmara

Answer 1

The solution is to change the signature a bit:

app.MapGet("/api/alive", () => Results.NoContent());

(context) alone does not work, Edit: as well as (RequestDelegate context) does not work.

app.MapGet("/api/alive", (context) => Results.NoContent());
app.MapGet("/api/alive", (RequestDelegate context) => Results.NoContent());

Marmara

Really frustrated with this. Is it a bug? Is there a work around? Trying to map to a handler function so I can use attributes, etc, and ASP.NET 6 always returns an empty 200 even when I return an IResult from the handler. – Camboose

You can make it even simpler. app.MapGet("/api/alive", Results.NoContent);. – Propend