private static void Redirect(IMutableWebResponse response, string redirectUri)
{
Trace.TraceInformation("Redirecting to {0}", redirectUri);
response.StatusCode = 302;
response.RedirectLocation = redirectUri;
}
private void BuildResponse(IMutableWebResponse response, IWebResponse proxyResponse)
{
response.ProtocolVersion = proxyResponse.ProtocolVersion;
response.ContentType = proxyResponse.ContentType;
response.StatusCode = (int)proxyResponse.StatusCode;
response.StatusDescription = proxyResponse.StatusDescription;
if (proxyResponse.ContentLength >= 0)
{
response.ContentLength = proxyResponse.ContentLength;
}
if (proxyResponse.Headers.ContainsKey("Content-Encoding") && !String.IsNullOrWhiteSpace(proxyResponse.ContentEncoding))
{
response.ContentEncoding = Encoding.GetEncoding(proxyResponse.ContentEncoding);
}
if (proxyResponse.Headers.ContainsKey("Location"))
{
response.RedirectLocation = proxyResponse.Headers["Location"];
}
if (proxyResponse.Headers.ContainsKey("Keep-Alive"))
{
bool keepAlive;
if (Boolean.TryParse(proxyResponse.Headers["Keep-Alive"], out keepAlive))
{
response.KeepAlive = keepAlive;
}
}
foreach (var cookie in proxyResponse.Cookies)
{
response.Cookies.Add(cookie);
}
foreach (var header in proxyResponse.Headers)
{
if (header.Key.StartsWith("Proxy-"))
{
continue; // Ignore proxy headers
}
if (PropertyHeaders.Contains(header.Key))
{
continue;
}
response.Headers.Add(header.Key, header.Value);
}
var proxyStream = proxyResponse.GetStream();
var requestStream = response.GetStream();
proxyStream.CopyTo(requestStream);
requestStream.Close();
}
private static void CustomAction(IMutableWebResponse response, HttpStatusCode customResultStatus, Stream customResultStream)
{
if (customResultStatus == 0)
{
customResultStatus = HttpStatusCode.OK;
}
response.StatusCode = (int)customResultStatus;
var responseStream = response.GetStream();
customResultStream.CopyTo(responseStream);
responseStream.Close();
}
public void ProcessRequest(IWebRequest request,
IMutableWebResponse response, IPrincipal user,
IEnumerable <IWebRequestFilter> requestFilters,
IEnumerable <IWebResponseFilter> responseFilters)
{
Trace.TraceInformation("Responding to request: {0}", request.RawUrl);
try
{
// Filter request
var requestFilterResult = FilterRequest(request, requestFilters);
if (requestFilterResult.Action == (requestFilterResult.Action | FilterResultAction.Block))
{
Trace.TraceInformation("Blocking request.");
if (requestFilterResult.Action == (requestFilterResult.Action | FilterResultAction.Redirect))
{
Redirect(response, requestFilterResult.RedirectUrl);
return;
}
if (requestFilterResult.Action == (requestFilterResult.Action | FilterResultAction.CustomResult))
{
CustomAction(response, requestFilterResult.CustomResultStatus, requestFilterResult.CustomResultStream);
return;
}
var message = String.Format("Request for {0} was blocked by a filter", request.RawUrl);
var data = Encoding.Default.GetBytes(message);
var messageStream = new MemoryStream(data);
CustomAction(response, HttpStatusCode.OK, messageStream);
return;
}
Trace.TraceInformation("Proxying request");
// Build proxy request
var requestBuilder = new ProxyRequestBuilder(_webRequestFactory, request);
var proxyRequest = requestBuilder.Build();
// Get proxy response
Trace.TraceInformation("Getting proxy response");
using (var proxyResponse = proxyRequest.GetResponse())
{
var responseFilterResult = FilterResponse(proxyResponse, responseFilters);
if (responseFilterResult.Action == (responseFilterResult.Action | FilterResultAction.Block))
{
Trace.TraceInformation("Blocking request.");
if (responseFilterResult.Action == (responseFilterResult.Action | FilterResultAction.Redirect))
{
Redirect(response, responseFilterResult.RedirectUrl);
return;
}
if (responseFilterResult.Action == (responseFilterResult.Action | FilterResultAction.CustomResult))
{
CustomAction(response, responseFilterResult.CustomResultStatus, responseFilterResult.CustomResultStream);
return;
}
var message = String.Format("Request for {0} was blocked by a filter", request.RawUrl);
var data = Encoding.Default.GetBytes(message);
var messageStream = new MemoryStream(data);
CustomAction(response, HttpStatusCode.OK, messageStream);
return;
}
Trace.TraceInformation("Forwarding proxy response");
BuildResponse(response, proxyResponse);
}
}
catch (HttpListenerException hEx)
{
if (hEx.ErrorCode == 64)
{
Trace.TraceWarning("Stream aborted");
}
else
{
Trace.TraceError("Error processing request: {0}", hEx);
var data = Encoding.Default.GetBytes("SimpleProxy: Error Processing Request.");
var messageStream = new MemoryStream(data);
CustomAction(response, HttpStatusCode.InternalServerError, messageStream);
}
}
catch (ProxyResponseException wEx)
{
if (wEx.Response != null)
{
BuildResponse(response, wEx.Response);
}
if (wEx.Status == WebExceptionStatus.NameResolutionFailure)
{
Trace.TraceWarning("Name Resolution Failure, redirecting to search: {0}", request.RawUrl);
Redirect(response, String.Format("http://www.google.com/search?q={0}", HttpUtility.UrlEncode(request.RawUrl)));
}
else
{
Trace.TraceError("Error processing request: {0}", wEx);
var data = Encoding.Default.GetBytes(String.Format("SimpleProxy: Error Processing Request: {0}", wEx.Message));
var messageStream = new MemoryStream(data);
CustomAction(response, HttpStatusCode.InternalServerError, messageStream);
}
}
catch (Exception ex)
{
Trace.TraceError("Error processing request: {0}", ex);
var data = Encoding.Default.GetBytes("SimpleProxy: Error Processing Request.");
var messageStream = new MemoryStream(data);
CustomAction(response, HttpStatusCode.InternalServerError, messageStream);
}
}
/// <param name="user">Identity, authentication, and security information of the client making the request.</param>
/// <param name="request">Client request</param>
/// <param name="response">Response that will be sent back to the client</param>
public ListenerRequestEventArgs(IPrincipal user, IWebRequest request, IMutableWebResponse response)
{
User = user;
Request = request;
Response = response;
}
