public static Action DownloadAsync(string url, string auth, string referer, string connectionGroupName, DateTime?cacheLastModifiedTime, Action <HttpWebResponse> onResponse, Action <byte[], int> onDownloadChunk, Action onComplete, Action <Exception> onException)
{
const int readBufferSize = 8192;
const int requestTimeoutMS = 60000;
const int readTimeoutMS = 60000;
object sync = new object();
bool aborting = false;
HttpWebRequest request = null;
HttpWebResponse response = null;
Stream responseStream = null;
Action cleanup = () => {
if (request != null)
{
request.Abort();
request = null;
}
if (responseStream != null)
{
try { responseStream.Close(); }
catch { }
responseStream = null;
}
if (response != null)
{
try { response.Close(); }
catch { }
response = null;
}
};
Action <Exception> abortDownloadInternal = (ex) => {
lock (sync) {
if (aborting)
{
return;
}
aborting = true;
cleanup();
onException(ex);
}
};
Action abortDownload = () => {
ThreadPool.QueueUserWorkItem((s) => {
abortDownloadInternal(new Exception("Download has been aborted."));
});
};
lock (sync) {
try {
request = BuildWebRequest(url: url, auth: auth, connectionGroupName: connectionGroupName, cacheLastModifiedTime: cacheLastModifiedTime, referer: referer);
// Unfortunately BeginGetResponse blocks until the DNS lookup has finished
IAsyncResult requestResult = request.BeginGetResponse((requestResultParam) => {
lock (sync) {
try {
if (aborting)
{
return;
}
response = (HttpWebResponse)request.EndGetResponse(requestResultParam);
if (GetMIMETypeFromContentType(response.ContentType) == "text/html")
{
var memoryStream = new MemoryStream();
CopyStream(new ThrottledStream(response.GetResponseStream(), Settings.MaximumBytesPerSecond ?? ThrottledStream.Infinite), memoryStream);
memoryStream.Position = 0;
byte[] redirectPageBytes = memoryStream.ToArray();
Encoding pageEncoding = DetectHTMLEncoding(redirectPageBytes, response.ContentType);
string metaRedirectHtml = pageEncoding.GetString(redirectPageBytes);
memoryStream.Position = 0;
responseStream = memoryStream;
string redirectUrl = GetRedirectUrl(metaRedirectHtml, response.ResponseUri.AbsoluteUri);
if (!string.IsNullOrEmpty(redirectUrl))
{
HttpWebRequest redirectionRequest = BuildWebRequest(url: redirectUrl, auth: auth, connectionGroupName: connectionGroupName, cacheLastModifiedTime: cacheLastModifiedTime);
response = (HttpWebResponse)redirectionRequest.GetResponse();
responseStream = new ThrottledStream(response.GetResponseStream(), Settings.MaximumBytesPerSecond ?? ThrottledStream.Infinite);
}
}
else
{
responseStream = new ThrottledStream(response.GetResponseStream(), Settings.MaximumBytesPerSecond ?? ThrottledStream.Infinite);
}
onResponse(response);
byte[] buff = new byte[readBufferSize];
AsyncCallback readCallback = null;
readCallback = (readResultParam) => {
lock (sync) {
try {
if (aborting)
{
return;
}
if (readResultParam != null)
{
int bytesRead = responseStream.EndRead(readResultParam);
if (bytesRead == 0)
{
request = null;
onComplete();
aborting = true;
cleanup();
return;
}
onDownloadChunk(buff, bytesRead);
}
IAsyncResult readResult = responseStream.BeginRead(buff, 0, buff.Length, readCallback, null);
ThreadPool.RegisterWaitForSingleObject(readResult.AsyncWaitHandle,
(state, timedOut) => {
if (!timedOut)
{
return;
}
abortDownloadInternal(new Exception("Timed out while reading response."));
}, null, readTimeoutMS, true);
}
catch (Exception ex) {
abortDownloadInternal(ex);
}
}
};
readCallback(null);
}
catch (Exception ex) {
if (ex is WebException)
{
WebException webEx = (WebException)ex;
if (webEx.Status == WebExceptionStatus.ProtocolError)
{
HttpStatusCode code = ((HttpWebResponse)webEx.Response).StatusCode;
if (code == HttpStatusCode.NotFound)
{
ex = new HTTP404Exception();
}
else if (code == HttpStatusCode.NotModified)
{
ex = new HTTP304Exception();
}
}
}
abortDownloadInternal(ex);
}
}
}, null);
ThreadPool.RegisterWaitForSingleObject(requestResult.AsyncWaitHandle,
(state, timedOut) => {
if (!timedOut)
{
return;
}
abortDownloadInternal(new Exception("Timed out while waiting for response."));
}, null, requestTimeoutMS, true);
}
catch (Exception ex) {
abortDownloadInternal(ex);
}
}
return(abortDownload);
}
public static Action DownloadAsync(string url, string auth, string referer, string connectionGroupName, DateTime?cacheLastModifiedTime, Action <HttpWebResponse> onResponse, Action <byte[], int> onDownloadChunk, Action onComplete, Action <Exception> onException)
{
const int readBufferSize = 8192;
const int requestTimeoutMS = 60000;
const int readTimeoutMS = 60000;
object sync = new object();
bool aborting = false;
HttpWebRequest request = null;
HttpWebResponse response = null;
Stream responseStream = null;
Action cleanup = () => {
if (request != null)
{
request.Abort();
request = null;
}
if (responseStream != null)
{
try { responseStream.Close(); }
catch { }
responseStream = null;
}
if (response != null)
{
try { response.Close(); }
catch { }
response = null;
}
};
Action <Exception> abortDownloadInternal = (ex) => {
lock (sync) {
if (aborting)
{
return;
}
aborting = true;
cleanup();
onException(ex);
}
};
Action abortDownload = () => {
ThreadPool.QueueUserWorkItem((s) => {
abortDownloadInternal(new Exception("Download has been aborted."));
});
};
lock (sync) {
try {
request = (HttpWebRequest)WebRequest.Create(url);
if (connectionGroupName != null)
{
request.ConnectionGroupName = connectionGroupName;
}
request.UserAgent = (Settings.UseCustomUserAgent == true) ? Settings.CustomUserAgent : ("Chan Thread Watch " + Version);
request.Referer = referer;
if (cacheLastModifiedTime != null)
{
request.IfModifiedSince = cacheLastModifiedTime.Value;
}
if (!String.IsNullOrEmpty(auth))
{
Encoding encoding = Encoding.GetEncoding("iso-8859-1");
request.Headers.Add("Authorization", "Basic " + Convert.ToBase64String(encoding.GetBytes(auth)));
}
// Unfortunately BeginGetResponse blocks until the DNS lookup has finished
IAsyncResult requestResult = request.BeginGetResponse((requestResultParam) => {
lock (sync) {
try {
if (aborting)
{
return;
}
response = (HttpWebResponse)request.EndGetResponse(requestResultParam);
responseStream = new ThrottledStream(response.GetResponseStream(), Settings.MaximumBytesPerSecond ?? ThrottledStream.Infinite);
onResponse(response);
byte[] buff = new byte[readBufferSize];
AsyncCallback readCallback = null;
readCallback = (readResultParam) => {
lock (sync) {
try {
if (aborting)
{
return;
}
if (readResultParam != null)
{
int bytesRead = responseStream.EndRead(readResultParam);
if (bytesRead == 0)
{
request = null;
onComplete();
aborting = true;
cleanup();
return;
}
onDownloadChunk(buff, bytesRead);
}
IAsyncResult readResult = responseStream.BeginRead(buff, 0, buff.Length, readCallback, null);
ThreadPool.RegisterWaitForSingleObject(readResult.AsyncWaitHandle,
(state, timedOut) => {
if (!timedOut)
{
return;
}
abortDownloadInternal(new Exception("Timed out while reading response."));
}, null, readTimeoutMS, true);
}
catch (Exception ex) {
abortDownloadInternal(ex);
}
}
};
readCallback(null);
}
catch (Exception ex) {
if (ex is WebException)
{
WebException webEx = (WebException)ex;
if (webEx.Status == WebExceptionStatus.ProtocolError)
{
HttpStatusCode code = ((HttpWebResponse)webEx.Response).StatusCode;
if (code == HttpStatusCode.NotFound)
{
ex = new HTTP404Exception();
}
else if (code == HttpStatusCode.NotModified)
{
ex = new HTTP304Exception();
}
}
}
abortDownloadInternal(ex);
}
}
}, null);
ThreadPool.RegisterWaitForSingleObject(requestResult.AsyncWaitHandle,
(state, timedOut) => {
if (!timedOut)
{
return;
}
abortDownloadInternal(new Exception("Timed out while waiting for response."));
}, null, requestTimeoutMS, true);
}
catch (Exception ex) {
abortDownloadInternal(ex);
}
}
return(abortDownload);
}
