/** Execute Head Request **************************************************/
private async Task <MacroscopeRedirectChainDocStruct> _ExecuteHeadCheck(string Url)
{
MacroscopeHttpTwoClientResponse ClientResponse = null;
Uri DocUri = null;
MacroscopeRedirectChainDocStruct RedirectChainDocStruct = new MacroscopeRedirectChainDocStruct();
try
{
DocUri = new Uri(Url);
ClientResponse = await this.HttpClient.Head(
DocUri,
this.ConfigureHeadRequestHeadersCallback,
this.PostProcessRequestHttpHeadersCallback
);
}
catch (Exception ex)
{
this.DebugMsg(string.Format("_ExecuteHeadCheck :: Exception: {0}", ex.Message));
}
if (ClientResponse != null)
{
RedirectChainDocStruct = this.ProcessResponseHttpHeaders(Url: Url, Response: ClientResponse);
}
return(RedirectChainDocStruct);
}
/** Perform Probe *********************************************************/
private async Task <MacroscopeRedirectChainDocStruct> Probe(string Url)
{
MacroscopeRedirectChainDocStruct RedirectChainDocStruct;
try
{
if (this.RedirectChainDocCache.ContainsKey(Url))
{
lock (this.RedirectChainDocCache)
{
RedirectChainDocStruct = this.RedirectChainDocCache[Url];
}
}
else
{
RedirectChainDocStruct = new MacroscopeRedirectChainDocStruct();
try
{
RedirectChainDocStruct = await this._ExecuteHeadCheck(Url : Url);
lock (this.RedirectChainDocCache)
{
if (this.RedirectChainDocCache.ContainsKey(Url))
{
this.RedirectChainDocCache.Remove(Url);
}
this.RedirectChainDocCache.Add(Url, RedirectChainDocStruct);
}
}
catch (Exception ex)
{
this.DebugMsg(string.Format("_Probe :: Exception: {0}", ex.Message));
}
}
}
catch (Exception ex)
{
RedirectChainDocStruct = new MacroscopeRedirectChainDocStruct();
this.DebugMsg(ex.Message);
}
return(RedirectChainDocStruct);
}
/**************************************************************************/
private MacroscopeRedirectChainDocStruct ProcessResponseHttpHeaders(string Url, MacroscopeHttpTwoClientResponse Response)
{
HttpResponseMessage ResponseMessage = Response.GetResponse();
HttpResponseHeaders ResponseHeaders = ResponseMessage.Headers;
HttpContentHeaders ContentHeaders = ResponseMessage.Content.Headers;
MacroscopeRedirectChainDocStruct RedirectChainDocStruct = new MacroscopeRedirectChainDocStruct();
/** HTTP Status Code ------------------------------------------------- **/
RedirectChainDocStruct.StatusCode = Response.GetResponse().StatusCode;
/** URL ------------------------------------------------- **/
RedirectChainDocStruct.Url = Url;
/** Location HTTP Header --------------------------------------------- **/
try
{
Uri HeaderValue = ResponseHeaders.Location;
if (HeaderValue != null)
{
RedirectChainDocStruct.RedirectUrl = HeaderValue.ToString();
}
}
catch (Exception ex)
{
this.DebugMsg(ex.Message);
FindHttpResponseHeaderCallback Callback = delegate(IEnumerable <string> HeaderValues)
{
RedirectChainDocStruct.RedirectUrl = HeaderValues.First().ToString();
return(true);
};
if (!this.FindHttpResponseHeader(ResponseHeaders: ResponseHeaders, HeaderName: "location", Callback: Callback))
{
this.FindHttpContentHeader(ContentHeaders: ContentHeaders, HeaderName: "location", Callback: Callback);
}
}
/** ------------------------------------------------------------------ **/
return(RedirectChainDocStruct);
}
/**************************************************************************/
public async Task <List <MacroscopeRedirectChainDocStruct> > AnalyzeRedirectChains(
HttpStatusCode StatusCode,
string StartUrl,
string RedirectUrl
)
{
List <MacroscopeRedirectChainDocStruct> RedirectChain = new List <MacroscopeRedirectChainDocStruct>();
int MaxHops = MacroscopePreferencesManager.GetRedirectChainsMaxHops();
MacroscopeRedirectChainDocStruct StructStart;
int IHOP = 0;
string PrevUrl = null;
string NextUrl = null;
try
{
try
{
StructStart = new MacroscopeRedirectChainDocStruct(
NewStatusCode: StatusCode,
NewUrl: StartUrl,
NewRedirectUrl: RedirectUrl
);
RedirectChain.Add(StructStart);
PrevUrl = StructStart.Url;
NextUrl = StructStart.RedirectUrl;
}
catch (Exception ex)
{
this.DebugMsg(ex.Message);
}
do
{
MacroscopeRedirectChainDocStruct StructNext;
try
{
if (!string.IsNullOrEmpty(PrevUrl))
{
NextUrl = MacroscopeHttpUrlUtils.MakeUrlAbsolute(PrevUrl, NextUrl);
}
StructNext = await this.Probe(Url : NextUrl);
RedirectChain.Add(StructNext);
PrevUrl = StructNext.Url;
NextUrl = StructNext.RedirectUrl;
switch (StructNext.StatusCode)
{
case HttpStatusCode.Found:
break;
case HttpStatusCode.Moved:
break;
case HttpStatusCode.SeeOther:
break;
case HttpStatusCode.TemporaryRedirect:
break;
default:
IHOP = MaxHops;
break;
}
}
catch (Exception ex)
{
this.DebugMsg(ex.Message);
}
IHOP++;
}while(IHOP < MaxHops);
}
catch (Exception ex)
{
this.DebugMsg(ex.Message);
}
return(RedirectChain);
}
