private Func <Task <HttpResponseMessage>, HttpResponseMessage> ContinuationFunction(HttpClient client, HttpContentHeaders contentHeaders, Route route, Models.Routing routing)
{
return(task =>
{
client.Dispose();
if (task.IsCanceled)
{
_proxyLogging.LogResponseCancelled(route, client.DefaultRequestHeaders, contentHeaders, task.Exception);
if (route.IsPrimary)
{
//Will display underlying exception
return task.Result;
}
return null;
}
if (task.IsFaulted)
{
_proxyLogging.LogResponseFaulted(route, client.DefaultRequestHeaders, contentHeaders, task.Exception);
if (route.IsPrimary)
{
//Will display underlying exception
return task.Result;
}
return null;
}
if (task.IsCompleted)
{
var memoryStream = new MemoryStream();
var encoding = System.Text.Encoding.UTF8;
int replacements = SearchReplace(task.Result.Content.ReadAsStreamAsync().Result, memoryStream,
encoding.GetBytes(routing.RewriteFrom.ToLower()), encoding.GetBytes(routing.RewriteTo));
_proxyLogging.LogResponseContent(new MemoryStream(memoryStream.GetBuffer()), route.Identifier);
if (route.IsPrimary)
{
var result = new HttpResponseMessage(task.Result.StatusCode);
result.Headers.Clear();
result.Headers.Add("X-Response-From", route.Uri.ToString());
// May be useful for debugging
//result.Headers.Add("X-MemoryStream-Length", $"{memoryStream.Length}");
result.Headers.Add("X-Replacement", $"{routing.RewriteFrom} to {routing.RewriteTo}: {replacements}");
result.Content = new ByteArrayContent(memoryStream.GetBuffer(), 0, (int)memoryStream.Length);
result.Content.Headers.Add("Content-Length", $"{memoryStream.Length}");
foreach (var header in task.Result.Content.Headers)
{
if (!result.Content.Headers.Contains(header.Key))
{
result.Content.Headers.Add(header.Key, header.Value);
}
}
return result;
}
else
{
return null;
}
}
throw new Exception("Unhandled");
});
}
private Task <HttpResponseMessage> GetAsyncRequest(HttpRequestMessage request, Route route, Models.Routing routing)
{
var client = RoutingHttpClientFactory.Create(request, route.Uri);
return(client.GetAsync(route.Uri).ContinueWith(ContinuationFunction(client, null, route, routing)));
}
private Task <HttpResponseMessage> PostAsyncRequest(HttpRequestMessage request, HttpContent requestHttpContent, Route route, Models.Routing routing)
{
var client = RoutingHttpClientFactory.Create(request, route.Uri);
var contentHeaders = request.Content?.Headers;
return(client.PostAsync(route.Uri, requestHttpContent).ContinueWith(ContinuationFunction(client, contentHeaders, route, routing)));
}
