Data models not showing up in HttpResponseMessage

Question

I\'m trying to make a simple API call from a .NET Core MVC application:

using (var client = new HttpClient())
{
    client.BaseAddress = new Uri(\"http://loc         


        

Answer 1

What exactly is being returned, and why isn't my list of models in the response?

What's being returned is a JSON-serialized version of your HttpResponseMessage, because while Web API 2 handles this type specially, ASP.NET Core web API does not.

To be precise, ASP.NET Core web API supports returning the following types:

• IActionResult
• ActionResult<T>
• <any other type>

The first two are treated specially, but the third results in that type being JSON-serialized and returned, exactly as you saw.

In contrast, Web API 2 supports the following special return types:

• void
• HttpResponseMessage
• IHttpActionResult
• <any other type>

The correct solution is to update your code to use a custom IActionResult implementation instead of returning raw HttpResponseMessages. You may find this guide aids you in doing so - in particular, the Microsoft.AspNetCore.Mvc.WebApiCompatShim NuGet package has a ResponseMessageResult class that allows you to convert your Web API controller method from this:

public HttpResponseMessage Foo(Bar quux)
{
    return new BazHttpResponseMessage();
}

to this:

public IActionResult Foo(Bar quux)
{
    return new ResponseMessageResult(new BazHttpResponseMessage());
}

which should allow your current code to work as-is.