public static HttpWebRequestOptions Combine(IHttpWebRequestOptions options1, IHttpWebRequestOptions options2, bool copyIfNull = true)
{
HttpWebRequestOptions result = new HttpWebRequestOptions(options1);
result.Combine(options2, copyIfNull);
return(result);
}
private IHttpWebRequestOptions GetOptions(Uri endpoint)
{
lock (webRequestOptions) {
OptionsInfo optionsInfo = webRequestOptions.Where(pair => endpoint.AbsoluteUri.StartsWith(pair.Key.AbsoluteUri))
.OrderByDescending(pair => pair.Key.AbsoluteUri.Length)
.Select(pair => pair.Value)
.FirstOrDefault();
if (optionsInfo is null)
{
return(defaultWebRequestOptions);
}
return(HttpWebRequestOptions.Combine(defaultWebRequestOptions, optionsInfo.WebRequestOptions, optionsInfo.CopyIfNull));
}
}
public IHttpWebRequestOptions GetOptions(Uri uri)
{
HttpWebRequestOptions options = new HttpWebRequestOptions(GetOptions());
IHttpWebRequestOptions uriOptions;
lock (uriOptionsMutex) {
uriOptions = FindOptionsByUri(uri.AbsoluteUri);
}
if (!(uriOptions is null))
{
uriOptions.CopyTo(options);
}
return(options);
}
// Protected members
protected override IHttpWebResponse Send(IHttpWebRequest request, CancellationToken cancellationToken)
{
if (request is null)
{
throw new ArgumentNullException(nameof(request));
}
// If redirects are not to be handled, simply pass down the request.
if (!request.AllowAutoRedirect)
{
return(base.Send(request, cancellationToken));
}
int maximumRedirections = request.MaximumAutomaticRedirections;
request.AllowAutoRedirect = false;
try {
IHttpWebResponse response = null;
for (int redirections = 0; redirections < maximumRedirections; ++redirections)
{
response = base.Send(request, cancellationToken);
if (response is object && IsRedirectStatusCode(response.StatusCode))
{
if (response.Headers.TryGetHeader(HttpResponseHeader.Location, out string locationValue) && !string.IsNullOrWhiteSpace(locationValue))
{
try {
// Follow the redirect to the new location.
if (Uri.TryCreate(request.RequestUri, locationValue, out Uri locationUri) && (locationUri.Scheme == Uri.UriSchemeHttp || locationUri.Scheme == Uri.UriSchemeHttps))
{
Uri originalUri = request.RequestUri;
string originalMethod = request.Method;
request = httpWebRequestFactory.Create(locationUri)
.WithOptions(HttpWebRequestOptions.FromHttpWebRequest(request));
if (response.StatusCode == HttpStatusCode.RedirectKeepVerb)
{
request.Method = originalMethod;
}
// If the host is the same, use the full path as the referer.
// However, if the hosts are different, we'll just use the root path as the referer (this is how Chrome handles it).
if (Uri.Compare(originalUri, locationUri, UriComponents.Host, UriFormat.Unescaped, StringComparison.OrdinalIgnoreCase) == 0)
{
request.Referer = originalUri.AbsoluteUri;
}
else
{
request.Referer = originalUri.GetLeftPart(UriPartial.Authority) + "/";
}
}
else
{
// The location URI was malformed.
throw new WebException(Properties.ExceptionMessages.CannotRedirectToDissimilarProtocols, null, WebExceptionStatus.ProtocolError, response as WebResponse);
}
}
finally {
response.Close();
}
}
else
{
// We did not receive a location header even though we were supposed to.
response.Close();
throw new WebException(string.Format(Properties.ExceptionMessages.TheRemoteServerReturnedAnErrorWithStatusCode, response.StatusCode), null, WebExceptionStatus.ProtocolError, response as WebResponse);
}
}
else
{
// We did not receive an HTTP redirection.
return(response);
}
}
// If we get here, we reached the maximum number of redirections.
response?.Close();
throw new WebException(Properties.ExceptionMessages.TooManyAutomaticRedirections, null, WebExceptionStatus.ProtocolError, response as WebResponse);
}
finally {
request.AllowAutoRedirect = true;
}
}
