Swagger UI does not show properly when custom message handler is used in web api 2

[abdulqayyum]

I am implementing a generic response for my web api 2 project. I implemented a delegatingHandler that create a response with my custom response type.

class WrappingHandler : DelegatingHandler{
...
}

Registered it in WebApiConfig before routes like

config.MessageHandlers.Add(new WrappingHandler());

I have swashbuckle 5.6.0 installed when I comment above line swagger UI shows up. However, with above code UI does not show any API controllers. Only this show up:

{"StatusCode":200,"ErrorMessage":null,"response":null}

There is no error in console and UI works fine otherwise.

[duyhau206]

I have same issue. Can anyone help please?

[Alchoder]

Same