ActionResult OK returns 204 on an empty payload instead of 200

[Mladen Mihajlović]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

This bug has been reported before in #8847 but was unceremoniously closed as working by design, all the while everyone in the thread (including @brunolins16 who closed the bug) has said that it is confusing and bad. I would more state that it is still a bug and should be fixed. (also why is the issue closed to discussion? Nobody was getting rowdy or rude...)

The fact is that when I say I want to return ActionResult of Ok() that is a specific status code and it is what should be returned. There is a specific method to return NoContent. So basically the API is not honoring what the developer has requested.

workaround...

services.AddMvc(options => 
{
    var noContentFormatter = options.OutputFormatters.OfType<HttpNoContentOutputFormatter>().FirstOrDefault();
    if (noContentFormatter != null)
    {
        noContentFormatter.TreatNullValueAsNoContent = false;
    }
});

Yes there is a way to switch it off - but it's a global change and it means every single method needs to be re-tested to make sure the right status code is being returned - and it's the most important and used status code of all.

So my proposal is, change the default setting of HttpNoContentOutputFormatter.TreatNullValueAsNoContent to false and make it opt-in instead of opt-out. This was a bad default and should be fixed.

Documentation

I must also add that the xml documentation of Ok() says "Gets the HTTP status code: Status200OK" so the documentation is wrong too.

Expected Behavior

Expected behavior is for the status code asked for to be returned. If I want Ok() it should return 200, if NoContent() then 204.

Steps To Reproduce

Return Ok(null) from a controller method which returns 'ActionResult`

Exceptions (if any)

No response

.NET Version

8

Anything else?

No response