Repro for 204 status code not being documented

Author: jeremyVignelles

Controllers/HomeController.cs

@@ -1,12 +1,21 @@
-using Microsoft.AspNetCore.Mvc;
+using System;
+using Microsoft.AspNetCore.Mvc;
 
 namespace Repro.Controllers
 {
+    [ApiExplorerSettings(IgnoreApi = false, GroupName = nameof(HomeController))]
+    [Route("Home")]
     public class HomeController : Controller
     {
-        public string Index()
+        [HttpGet]
+        public string? Index()
         {
-            return "Hello !";
+            if (new Random().Next(100) > 50)
+            {
+                return "Hello !";
+            }
+
+            return null;
         }
     }
 }

Program.cs

@@ -1,4 +1,7 @@
+using System;
 using Microsoft.AspNetCore.Hosting;
+using Microsoft.AspNetCore.Mvc.ApiExplorer;
+using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
 
 namespace Repro
@@ -7,7 +10,19 @@ public class Program
     {
         public static void Main(string[] args)
         {
-            CreateHostBuilder(args).Build().Run();
+            var host = CreateHostBuilder(args).Build();
+            var provider = host.Services.GetRequiredService<IApiDescriptionGroupCollectionProvider>();
+            foreach (var group in provider.ApiDescriptionGroups.Items)
+            {
+                foreach (var item in group.Items)
+                {
+                    Console.WriteLine(item.RelativePath);
+                    foreach (var responseType in item.SupportedResponseTypes)
+                    {
+                        Console.WriteLine($" -- {responseType.StatusCode}");
+                    }
+                }
+            }
         }
 
         public static IHostBuilder CreateHostBuilder(string[] args) =>