private Yield HandleInvoke(Action<string> activity, Plug plug, string verb, XUri uri, DreamMessage request, Result<DreamMessage> response)
{
Result<IAsyncResult> async;
// remove internal headers
request.Headers.DreamTransport = null;
// set request headers
request.Headers.Host = uri.Host;
if(request.Headers.UserAgent == null) {
request.Headers.UserAgent = "Dream/" + DreamUtil.DreamVersion;
}
// add cookies to request
if(request.HasCookies) {
request.Headers[DreamHeaders.COOKIE] = DreamCookie.RenderCookieHeader(request.Cookies);
}
// initialize request
activity("pre WebRequest.Create");
var httpRequest = (HttpWebRequest)WebRequest.Create(uri.ToUri());
activity("post WebRequest.Create");
httpRequest.Method = verb;
httpRequest.Timeout = System.Threading.Timeout.Infinite;
httpRequest.ReadWriteTimeout = System.Threading.Timeout.Infinite;
// Note (arnec): httpRequest AutoRedirect is disabled because Plug is responsible for it (this allows redirects to follow
// the appropriate handler instead staying stuck in http end point land
httpRequest.AllowAutoRedirect = false;
// Note from http://support.microsoft.com/kb/904262
// The HTTP request is made up of the following parts:
// 1. Sending the request is covered by using the HttpWebRequest.Timeout method.
// 2. Getting the response header is covered by using the HttpWebRequest.Timeout method.
// 3. Reading the body of the response is not covered by using the HttpWebResponse.Timeout method. In ASP.NET 1.1 and in later versions, reading the body of the response
// is covered by using the HttpWebRequest.ReadWriteTimeout method. The HttpWebRequest.ReadWriteTimeout method is used to handle cases where the response headers are
// retrieved in a timely manner but where the reading of the response body times out.
httpRequest.KeepAlive = false;
httpRequest.ProtocolVersion = System.Net.HttpVersion.Version10;
// TODO (steveb): set default proxy
//httpRequest.Proxy = WebProxy.GetDefaultProxy();
//httpRequest.Proxy.Credentials = CredentialCache.DefaultCredentials;
// set credentials
if(plug.Credentials != null) {
httpRequest.Credentials = plug.Credentials;
httpRequest.PreAuthenticate = true;
} else if(!string.IsNullOrEmpty(uri.User) || !string.IsNullOrEmpty(uri.Password)) {
httpRequest.Credentials = new NetworkCredential(uri.User ?? string.Empty, uri.Password ?? string.Empty);
httpRequest.PreAuthenticate = true;
// Note (arnec): this manually adds the basic auth header, so it can authorize
// in a single request without requiring challenge
var authbytes = Encoding.ASCII.GetBytes(string.Concat(uri.User ?? string.Empty, ":", uri.Password ?? string.Empty));
var base64 = Convert.ToBase64String(authbytes);
httpRequest.Headers.Add(DreamHeaders.AUTHORIZATION, "Basic " + base64);
}
// add request headres
foreach(KeyValuePair<string, string> header in request.Headers) {
HttpUtil.AddHeader(httpRequest, header.Key, header.Value);
}
// send message stream
if((request.ContentLength != 0) || (verb == Verb.POST)) {
async = new Result<IAsyncResult>();
try {
activity("pre BeginGetRequestStream");
httpRequest.BeginGetRequestStream(async.Return, null);
activity("post BeginGetRequestStream");
} catch(Exception e) {
activity("pre HandleResponse 1");
if(!HandleResponse(activity, e, null, response)) {
_log.ErrorExceptionMethodCall(e, "HandleInvoke@BeginGetRequestStream", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
}
activity("pre yield BeginGetRequestStream");
yield return async.Catch();
activity("post yield BeginGetRequestStream");
// send request
Stream outStream;
try {
activity("pre EndGetRequestStream");
outStream = httpRequest.EndGetRequestStream(async.Value);
activity("pre EndGetRequestStream");
} catch(Exception e) {
activity("pre HandleResponse 2");
if(!HandleResponse(activity, e, null, response)) {
_log.ErrorExceptionMethodCall(e, "HandleInvoke@EndGetRequestStream", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
}
// copy data
using(outStream) {
Result<long> res;
activity("pre yield CopyStream");
yield return res = request.ToStream().CopyTo(outStream, request.ContentLength, new Result<long>(TimeSpan.MaxValue)).Catch();
activity("post yield CopyStream");
if(res.HasException) {
activity("pre HandleResponse 3");
if(!HandleResponse(activity, res.Exception, null, response)) {
_log.ErrorExceptionMethodCall(res.Exception, "*****@*****.**", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
}
}
}
request = null;
// wait for response
async = new Result<IAsyncResult>(response.Timeout);
try {
activity("pre BeginGetResponse");
httpRequest.BeginGetResponse(async.Return, null);
activity("post BeginGetResponse");
} catch(Exception e) {
activity("pre HandleResponse 4");
if(!HandleResponse(activity, e, null, response)) {
_log.ErrorExceptionMethodCall(e, "HandleInvoke@BeginGetResponse", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
}
activity("pre yield BeginGetResponse");
yield return async.Catch();
activity("post yield BeginGetResponse");
// check if an error occurred
if(async.HasException) {
activity("pre HandleResponse 5");
if(!HandleResponse(activity, async.Exception, null, response)) {
_log.ErrorExceptionMethodCall(async.Exception, "HandleInvoke@BeginGetResponse", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
} else {
// handle response
try {
HttpWebResponse httpResponse = (HttpWebResponse)httpRequest.EndGetResponse(async.Value);
activity("pre HandleResponse 6");
if(!HandleResponse(activity, null, httpResponse, response)) {
try {
httpRequest.Abort();
} catch { }
}
} catch(Exception e) {
activity("pre HandleResponse 7");
if(!HandleResponse(activity, e, null, response)) {
_log.ErrorExceptionMethodCall(e, "HandleInvoke@EndGetResponse", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
}
}
}
private Yield HandleInvoke(Action<string> activity, Plug plug, string verb, XUri uri, DreamMessage request, Result<DreamMessage> response)
{
Result<IAsyncResult> async;
// remove internal headers
request.Headers.DreamTransport = null;
// set request headers
request.Headers.Host = uri.Host;
if(request.Headers.UserAgent == null) {
request.Headers.UserAgent = "Dream/" + DreamUtil.DreamVersion;
}
// add cookies to request
if(request.HasCookies) {
request.Headers[DreamHeaders.COOKIE] = DreamCookie.RenderCookieHeader(request.Cookies);
}
// check if we can pool the request with an existing one
if((plug.Credentials == null) && StringUtil.ContainsInvariantIgnoreCase(verb, "GET")) {
// create the request hashcode
StringBuilder buffer = new StringBuilder();
buffer.AppendLine(uri.ToString());
foreach(KeyValuePair<string, string> header in request.Headers) {
buffer.Append(header.Key).Append(": ").Append(header.Value).AppendLine();
}
Guid hash = new Guid(StringUtil.ComputeHash(buffer.ToString()));
// check if an active connection exists
Result<DreamMessage> relay = null;
lock(_requests) {
List<Result<DreamMessage>> pending;
if(_requests.TryGetValue(hash, out pending)) {
relay = new Result<DreamMessage>(response.Timeout);
pending.Add(relay);
} else {
pending = new List<Result<DreamMessage>>();
pending.Add(response);
_requests[hash] = pending;
}
}
// check if we're pooling a request
if(relay != null) {
// wait for the relayed response
yield return relay;
response.Return(relay);
yield break;
} else {
// NOTE (steveb): we use TaskEnv.Instantaneous so that we don't exit the current stack frame before we've executed the continuation;
// otherwise, we'll trigger an exception because our result object may not be set.
// create new handler to multicast the response to the relays
response = new Result<DreamMessage>(response.Timeout, TaskEnv.Instantaneous);
response.WhenDone(_ => {
List<Result<DreamMessage>> pending;
lock(_requests) {
_requests.TryGetValue(hash, out pending);
_requests.Remove(hash);
}
// this check should never fail!
if(response.HasException) {
// send the exception to all relays
foreach(Result<DreamMessage> result in pending) {
result.Throw(response.Exception);
}
} else {
DreamMessage original = response.Value;
// only memorize the message if it needs to be cloned
if(pending.Count > 1) {
// clone the message to all relays
foreach(Result<DreamMessage> result in pending) {
result.Return(original.Clone());
}
} else {
// relay the original message
pending[0].Return(original);
}
}
});
}
}
// initialize request
activity("pre WebRequest.Create");
var httpRequest = (HttpWebRequest)WebRequest.Create(uri.ToUri());
activity("post WebRequest.Create");
httpRequest.Method = verb;
httpRequest.Timeout = System.Threading.Timeout.Infinite;
httpRequest.ReadWriteTimeout = System.Threading.Timeout.Infinite;
// Note (arnec): httpRequest AutoRedirect is disabled because Plug is responsible for it (this allows redirects to follow
// the appropriate handler instead staying stuck in http end point land
httpRequest.AllowAutoRedirect = false;
// Note from http://support.microsoft.com/kb/904262
// The HTTP request is made up of the following parts:
// 1. Sending the request is covered by using the HttpWebRequest.Timeout method.
// 2. Getting the response header is covered by using the HttpWebRequest.Timeout method.
// 3. Reading the body of the response is not covered by using the HttpWebResponse.Timeout method. In ASP.NET 1.1 and in later versions, reading the body of the response
// is covered by using the HttpWebRequest.ReadWriteTimeout method. The HttpWebRequest.ReadWriteTimeout method is used to handle cases where the response headers are
// retrieved in a timely manner but where the reading of the response body times out.
httpRequest.KeepAlive = false;
httpRequest.ProtocolVersion = System.Net.HttpVersion.Version10;
// TODO (steveb): set default proxy
//httpRequest.Proxy = WebProxy.GetDefaultProxy();
//httpRequest.Proxy.Credentials = CredentialCache.DefaultCredentials;
// set credentials
if(plug.Credentials != null) {
httpRequest.Credentials = plug.Credentials;
httpRequest.PreAuthenticate = true;
} else if(!string.IsNullOrEmpty(uri.User) || !string.IsNullOrEmpty(uri.Password)) {
httpRequest.Credentials = new NetworkCredential(uri.User ?? string.Empty, uri.Password ?? string.Empty);
httpRequest.PreAuthenticate = true;
// Note (arnec): this manually adds the basic auth header, so it can authorize
// in a single request without requiring challenge
var authbytes = Encoding.ASCII.GetBytes(string.Concat(uri.User ?? string.Empty, ":", uri.Password ?? string.Empty));
var base64 = Convert.ToBase64String(authbytes);
httpRequest.Headers.Add(DreamHeaders.AUTHORIZATION, "Basic " + base64);
}
// add request headres
foreach(KeyValuePair<string, string> header in request.Headers) {
HttpUtil.AddHeader(httpRequest, header.Key, header.Value);
}
// send message stream
if((request.ContentLength != 0) || (verb == Verb.POST)) {
async = new Result<IAsyncResult>();
try {
activity("pre BeginGetRequestStream");
httpRequest.BeginGetRequestStream(async.Return, null);
activity("post BeginGetRequestStream");
} catch(Exception e) {
activity("pre HandleResponse 1");
if(!HandleResponse(activity, e, null, response)) {
_log.ErrorExceptionMethodCall(e, "HandleInvoke@BeginGetRequestStream", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
}
activity("pre yield BeginGetRequestStream");
yield return async.Catch();
activity("post yield BeginGetRequestStream");
// send request
Stream outStream;
try {
activity("pre EndGetRequestStream");
outStream = httpRequest.EndGetRequestStream(async.Value);
activity("pre EndGetRequestStream");
} catch(Exception e) {
activity("pre HandleResponse 2");
if(!HandleResponse(activity, e, null, response)) {
_log.ErrorExceptionMethodCall(e, "HandleInvoke@EndGetRequestStream", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
}
// copy data
using(outStream) {
Result<long> res;
activity("pre yield CopyStream");
yield return res = request.ToStream().CopyTo(outStream, request.ContentLength, new Result<long>(TimeSpan.MaxValue)).Catch();
activity("post yield CopyStream");
if(res.HasException) {
activity("pre HandleResponse 3");
if(!HandleResponse(activity, res.Exception, null, response)) {
_log.ErrorExceptionMethodCall(res.Exception, "*****@*****.**", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
}
}
}
request = null;
// wait for response
async = new Result<IAsyncResult>(response.Timeout);
try {
activity("pre BeginGetResponse");
httpRequest.BeginGetResponse(async.Return, null);
activity("post BeginGetResponse");
} catch(Exception e) {
activity("pre HandleResponse 4");
if(!HandleResponse(activity, e, null, response)) {
_log.ErrorExceptionMethodCall(e, "HandleInvoke@BeginGetResponse", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
}
activity("pre yield BeginGetResponse");
yield return async.Catch();
activity("post yield BeginGetResponse");
// check if an error occurred
if(async.HasException) {
activity("pre HandleResponse 5");
if(!HandleResponse(activity, async.Exception, null, response)) {
_log.ErrorExceptionMethodCall(async.Exception, "HandleInvoke@BeginGetResponse", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
} else {
// handle response
try {
HttpWebResponse httpResponse = (HttpWebResponse)httpRequest.EndGetResponse(async.Value);
activity("pre HandleResponse 6");
if(!HandleResponse(activity, null, httpResponse, response)) {
try {
httpRequest.Abort();
} catch { }
}
} catch(Exception e) {
activity("pre HandleResponse 7");
if(!HandleResponse(activity, e, null, response)) {
_log.ErrorExceptionMethodCall(e, "HandleInvoke@EndGetResponse", verb, uri);
try {
httpRequest.Abort();
} catch { }
}
yield break;
}
}
}
