TestServer should call IHttpContextFactory.Create with valid featureCollection

[cortex93]

Hi,

I'm trying to set the TraceIdentifier from request headers early in the request processing before HostingApplication begins the scope and logs it.
To do so, I’m reading HttpContext.Request.Headers in a custom HttpContextFactory.Create method. While it works with Kestrel, it doesn't with TestServer.

From what I understand, TestServer do not populate HttpContext from the IFeatureCollection but it calls IHttpApplication.CreateContext with a fake RequestFeature and modify the returned HttpContext before calling IHttpApplication.ProcessRequestAsync.

If that's not a bug, what is the correct usage and how could I achieve my requirement

[cortex93]

In RequestState, setting the RequestFeature properties directly with the one from given request.
I do the same with response,and finally create the Context to set the abortedSource token on it.

This make it works but I really don't know the implication.

[Tratcher]

Yes, we could do that. The only reason it hadn't been done that way was that it was more convenient to set fields via the HttpContext. See

Hosting/src/Microsoft.AspNetCore.TestHost/ClientHandler.cs

Lines 128 to 138 in b6da89f

	var contextFeatures = new FeatureCollection();
	contextFeatures.Set<IHttpRequestFeature>(new RequestFeature());
	_responseFeature = new ResponseFeature();
	contextFeatures.Set<IHttpResponseFeature>(_responseFeature);
	Context = application.CreateContext(contextFeatures);
	var httpContext = Context.HttpContext;
	var serverRequest = httpContext.Request;
	serverRequest.Protocol = "HTTP/" + request.Version.ToString(2);
	serverRequest.Scheme = request.RequestUri.Scheme;
	serverRequest.Method = request.Method.ToString();

[cortex93]

In fact, using the feature is also that convenient. Just replacing

Context = application.CreateContext(contextFeatures);
var httpContext = Context.HttpContext;
var serverRequest = httpContext.Request

with
var serverRequest = contextFeatures.Get<IHttpRequestFeature>();

does the trick. QueryString is of different type so .Value will be required for QueryString.FromUriComponent

At the end,

httpContext.Response.Body = _responseStream;
httpContext.Response.StatusCode = 200;
httpContext.RequestAborted = _requestAbortedSource.Token;

may be replace with

var responseFeature = contextFeatures.Get<IHttpResponseFeature>()
responseFeature.Body = _responseStream;
responseFeature.StatusCode = 200;
Context = application.CreateContext(contextFeatures);
Context.HttpContext.RequestAborted = _requestAbortedSource.Token;

[davidfowl]

@Tratcher let's make this change.

/cc @muratg