server/AyaNova/Startup.cs

@@ -62,6 +62,13 @@ namespace AyaNova
                               config.Filters.Add(new AyaNova.Api.ControllerHelpers.ApiCustomExceptionFilter(AyaNova.Util.ApplicationLogging.LoggerFactory));
                           });
 
+            //Prevent default model binding automatic 400 page so we can consistently show *our* error to our specs
+            //https://docs.microsoft.com/en-us/aspnet/core/web-api/index?view=aspnetcore-3.1#automatic-http-400-responses
+            MvcBuilder.ConfigureApiBehaviorOptions(options =>
+                    {
+                        options.SuppressModelStateInvalidFilter = true;
+                    });
+
             _log.LogDebug("BOOT: init JSON");
             MvcBuilder.AddNewtonsoftJson(options =>
                 {