//*************************************************************************
// Constructor: PartialNetworkException()
//
/// <summary>
/// Initializes a new instance of the <see
/// cref="PartialNetworkException" /> class.
/// </summary>
///
/// <param name="partialNetwork">
/// The partial network that was obtained.
/// </param>
///
/// <param name="requestStatistics">
/// Information about the requests that were made while getting the
/// network.
/// </param>
//*************************************************************************
public PartialNetworkException
(
XmlDocument partialNetwork,
RequestStatistics requestStatistics
)
{
m_oPartialNetwork = partialNetwork;
m_oRequestStatistics = requestStatistics;
AssertValid();
}
OnNetworkObtainedWithoutTerminatingException
(
GraphMLXmlDocument oGraphMLXmlDocument,
RequestStatistics oRequestStatistics
)
{
Debug.Assert(oGraphMLXmlDocument != null);
Debug.Assert(oRequestStatistics != null);
AssertValid();
if (oRequestStatistics.UnexpectedExceptions > 0)
{
// The network is partial.
throw new PartialNetworkException(oGraphMLXmlDocument,
oRequestStatistics);
}
}
GetXmlDocumentWithRetries
(
String sUrl,
HttpStatusCode [] aeHttpStatusCodesToFailImmediately,
RequestStatistics oRequestStatistics,
params String[] asOptionalHeaderNameValuePairs
)
{
Debug.Assert(!String.IsNullOrEmpty(sUrl));
Debug.Assert(oRequestStatistics != null);
Debug.Assert(asOptionalHeaderNameValuePairs == null ||
asOptionalHeaderNameValuePairs.Length % 2 == 0);
AssertValid();
Int32 iMaximumRetries = HttpRetryDelaysSec.Length;
Int32 iRetriesSoFar = 0;
while (true)
{
if (iRetriesSoFar > 0)
{
ReportProgress("Retrying request.");
}
// Important Note: You cannot use the same HttpWebRequest object
// for the retries. The object must be recreated each time.
HttpWebRequest oHttpWebRequest =
(HttpWebRequest)WebRequest.Create(sUrl);
Int32 iHeaderNamesAndValues =
(asOptionalHeaderNameValuePairs == null) ?
0 : asOptionalHeaderNameValuePairs.Length;
for (Int32 i = 0; i < iHeaderNamesAndValues; i += 2)
{
String sHeaderName = asOptionalHeaderNameValuePairs[i + 0];
String sHeaderValue = asOptionalHeaderNameValuePairs[i + 1];
Debug.Assert(!String.IsNullOrEmpty(sHeaderName));
Debug.Assert(!String.IsNullOrEmpty(sHeaderValue));
oHttpWebRequest.Headers[sHeaderName] = sHeaderValue;
}
try
{
XmlDocument oXmlDocument =
GetXmlDocumentNoRetries(oHttpWebRequest);
if (iRetriesSoFar > 0)
{
ReportProgress("Retry succeeded, continuing...");
}
oRequestStatistics.OnSuccessfulRequest();
return(oXmlDocument);
}
catch (Exception oException)
{
if (!ExceptionIsWebOrXml(oException))
{
throw oException;
}
// A WebException or XmlException has occurred.
if (iRetriesSoFar == iMaximumRetries)
{
oRequestStatistics.OnUnexpectedException(oException);
throw (oException);
}
// If the status code is one of the ones specified in
// aeHttpStatusCodesToFailImmediately, rethrow the exception
// without retrying the request.
if (aeHttpStatusCodesToFailImmediately != null &&
oException is WebException)
{
if (WebExceptionHasHttpStatusCode(
(WebException)oException,
aeHttpStatusCodesToFailImmediately))
{
throw (oException);
}
}
Int32 iSeconds = HttpRetryDelaysSec[iRetriesSoFar];
ReportProgress(String.Format(
"Request failed, pausing {0} {1} before retrying..."
,
iSeconds,
StringUtil.MakePlural("second", iSeconds)
));
System.Threading.Thread.Sleep(1000 * iSeconds);
iRetriesSoFar++;
}
}
}
