Это AsyncController ASP.Net MVC 3.0, который принимает запросы и преобразует входящий объект HttpRequestBase MVC в System.Web.HttpWebRequest. Затем он отправляет запрос асинхронно. Когда ответ возвращается, он преобразует System.Web.HttpWebResponse обратно в объект MVC HttpResponseBase, который может быть возвращен через контроллер MVC.
Чтобы ответить на этот вопрос явно, я думаю, вас будет интересовать только функция BuildWebRequest (). Однако он демонстрирует, как перемещаться по всему конвейеру - преобразование из BaseRequest> Request, а затем Response> BaseResponse. Я подумал, что будет полезно поделиться обоими.
С помощью этих классов у вас может быть сервер MVC, который действует как веб-прокси.
Надеюсь это поможет!
Контроллер:
[HandleError]
public class MyProxy : AsyncController
{
[HttpGet]
public void RedirectAsync()
{
AsyncManager.OutstandingOperations.Increment();
var hubBroker = new RequestBroker();
hubBroker.BrokerCompleted += (sender, e) =>
{
this.AsyncManager.Parameters["brokered"] = e.Response;
this.AsyncManager.OutstandingOperations.Decrement();
};
hubBroker.BrokerAsync(this.Request, redirectTo);
}
public ActionResult RedirectCompleted(HttpWebResponse brokered)
{
RequestBroker.BuildControllerResponse(this.Response, brokered);
return new HttpStatusCodeResult(Response.StatusCode);
}
}
Это прокси-класс, который выполняет тяжелую работу:
namespace MyProxy
{
internal class RequestBroker
{
private static readonly string[] RestrictedHeaders = new string[] { "Accept", "Connection", "Content-Length", "Content-Type", "Date", "Expect", "Host", "If-Modified-Since", "Range", "Referer", "Transfer-Encoding", "User-Agent", "Proxy-Connection" };
internal class BrokerEventArgs : EventArgs
{
public DateTime StartTime { get; set; }
public HttpWebResponse Response { get; set; }
}
public delegate void BrokerEventHandler(object sender, BrokerEventArgs e);
public event BrokerEventHandler BrokerCompleted;
public void BrokerAsync(HttpRequestBase requestToBroker, string redirectToUrl)
{
var httpRequest = BuildWebRequest(requestToBroker, redirectToUrl);
var brokerTask = new Task(() => this.DoBroker(httpRequest));
brokerTask.Start();
}
private void DoBroker(HttpWebRequest requestToBroker)
{
var startTime = DateTime.UtcNow;
HttpWebResponse response;
try
{
response = requestToBroker.GetResponse() as HttpWebResponse;
}
catch (WebException e)
{
Trace.TraceError("Broker Fail: " + e.ToString());
response = e.Response as HttpWebResponse;
}
var args = new BrokerEventArgs()
{
StartTime = startTime,
Response = response,
};
this.BrokerCompleted(this, args);
}
public static void BuildControllerResponse(HttpResponseBase httpResponseBase, HttpWebResponse brokeredResponse)
{
if (brokeredResponse == null)
{
PerfCounters.ErrorCounter.Increment();
throw new GriddleException("Failed to broker a response. Refer to logs for details.");
}
httpResponseBase.Charset = brokeredResponse.CharacterSet;
httpResponseBase.ContentType = brokeredResponse.ContentType;
foreach (Cookie cookie in brokeredResponse.Cookies)
{
httpResponseBase.Cookies.Add(CookieToHttpCookie(cookie));
}
foreach (var header in brokeredResponse.Headers.AllKeys
.Where(k => !k.Equals("Transfer-Encoding", StringComparison.InvariantCultureIgnoreCase)))
{
httpResponseBase.Headers.Add(header, brokeredResponse.Headers[header]);
}
httpResponseBase.StatusCode = (int)brokeredResponse.StatusCode;
httpResponseBase.StatusDescription = brokeredResponse.StatusDescription;
BridgeAndCloseStreams(brokeredResponse.GetResponseStream(), httpResponseBase.OutputStream);
}
private static HttpWebRequest BuildWebRequest(HttpRequestBase requestToBroker, string redirectToUrl)
{
var httpRequest = (HttpWebRequest)WebRequest.Create(redirectToUrl);
if (requestToBroker.Headers != null)
{
foreach (var header in requestToBroker.Headers.AllKeys)
{
if (RestrictedHeaders.Any(h => header.Equals(h, StringComparison.InvariantCultureIgnoreCase)))
{
continue;
}
httpRequest.Headers.Add(header, requestToBroker.Headers[header]);
}
}
httpRequest.Accept = string.Join(",", requestToBroker.AcceptTypes);
httpRequest.ContentType = requestToBroker.ContentType;
httpRequest.Method = requestToBroker.HttpMethod;
if (requestToBroker.UrlReferrer != null)
{
httpRequest.Referer = requestToBroker.UrlReferrer.AbsoluteUri;
}
httpRequest.UserAgent = requestToBroker.UserAgent;
httpRequest.Proxy = null;
if (requestToBroker.HttpMethod.Equals("POST", StringComparison.InvariantCultureIgnoreCase))
{
BridgeAndCloseStreams(requestToBroker.InputStream, httpRequest.GetRequestStream());
}
return httpRequest;
}
private static HttpCookie CookieToHttpCookie(Cookie cookie)
{
HttpCookie httpCookie = new HttpCookie(cookie.Name);
foreach (string value in cookie.Value.Split('&'))
{
string[] val = value.Split('=');
httpCookie.Values.Add(val[0], val[1]);
}
httpCookie.Domain = cookie.Domain;
httpCookie.Expires = cookie.Expires;
httpCookie.HttpOnly = cookie.HttpOnly;
httpCookie.Path = cookie.Path;
httpCookie.Secure = cookie.Secure;
return httpCookie;
}
private static void BridgeAndCloseStreams(Stream from, Stream to)
{
try
{
int read;
do
{
read = from.ReadByte();
if (read != -1)
{
to.WriteByte((byte)read);
}
}
while (read != -1);
}
finally
{
from.Close();
to.Close();
}
}
}
}