Send HttpRequestMessage in C++, Windows API UWP - c++

Question

This is not C++/CLI. This is UWP C++/CX
I am trying to send an HttpRequestMessage outside of a managed class in C++. I looked at the UWP samples, but their requests occur inside of a managed class.
All I want to do is send the request, and then have a callback function. I don't need fancy async/await patterns. This is looking to be a lot more difficult than it should be.
EDIT: I have gotten it to work, but the error handling is atrocious. The extra error handling code from the UWP HttpClient example was not compiling.
client = ref new Windows::Web::Http::HttpClient();
client->DefaultRequestHeaders->UserAgent->Append(ref new Windows::Web::Http::Headers::HttpProductInfoHeaderValue("Windows", "10"));
cancellation_token_source cancellationTokenSource = cancellation_token_source();
create_task(client->SendRequestAsync(message)).then([=](Windows::Web::Http::HttpResponseMessage^ response)
{
auto operation = response->Content->ReadAsBufferAsync();
auto task = create_task(operation);
if (task.wait() == task_status::completed)
{
webResponse->statusCode = (int)response->StatusCode;
auto buffer = task.get();
size_t length = buffer->Length;
if (length > 0)
{
Array<byte>^ array = nullptr;
CryptographicBuffer::CopyToByteArray(buffer, &array);
webResponse->contentLength = array->Length;
webResponse->data = (byte*)malloc(webResponse->contentLength);
memcpy(webResponse->data, array->Data, webResponse->contentLength);
delete array;
}
for each(IKeyValuePair<String^, String^>^ pair in response->Headers)
{
std::string key = PlatformStringToString(pair->Key);
std::string value = PlatformStringToString(pair->Value);
if (key == "Content-Type" && false)
{
// Should have this for completeness, but do we really care?
}
else
{
Web::WebHeader *header = new Web::WebHeader(key.c_str(), value.c_str());
webResponse->AddHeader(header);
}
}
if (request->receiveDoneCallback)
request->receiveDoneCallback(webResponse, request->userPtr);
}
else
abort();
delete request;
delete response;
});