protected override async Task <HttpResponseMessage> SendAsync(HttpRequestMessage requestMessage,
CancellationToken cancellationToken)
{
HttpResponseMessage response = null;
int backOffInSec = 1;
int totalRetryTime = 0;
int maxDefaultBackoff = 16;
ServicePoint p = ServicePointManager.FindServicePoint(requestMessage.RequestUri);
p.Expect100Continue = false; // Saves about 100 ms per request
p.UseNagleAlgorithm = false; // Saves about 200 ms per request
p.ConnectionLimit = 20; // Default value is 2, we need more connections for performing multiple parallel queries
TimeSpan httpTimeout = (TimeSpan)requestMessage.Properties[SFRestRequest.HTTP_REQUEST_TIMEOUT_KEY];
TimeSpan restTimeout = (TimeSpan)requestMessage.Properties[SFRestRequest.REST_REQUEST_TIMEOUT_KEY];
if (logger.IsDebugEnabled())
{
logger.Debug("Http request timeout : " + httpTimeout);
logger.Debug("Rest request timeout : " + restTimeout);
}
CancellationTokenSource childCts = null;
UriUpdater updater = new UriUpdater(requestMessage.RequestUri);
while (true)
{
try
{
childCts = null;
if (!httpTimeout.Equals(Timeout.InfiniteTimeSpan))
{
childCts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
childCts.CancelAfter(httpTimeout);
}
response = await base.SendAsync(requestMessage, childCts == null?
cancellationToken : childCts.Token).ConfigureAwait(false);
}
catch (Exception e)
{
if (cancellationToken.IsCancellationRequested)
{
logger.Debug("SF rest request timeout or explicit cancel called.");
cancellationToken.ThrowIfCancellationRequested();
}
else if (childCts != null && childCts.Token.IsCancellationRequested)
{
logger.Warn("Http request timeout. Retry the request");
totalRetryTime += (int)httpTimeout.TotalSeconds;
}
else
{
//TODO: Should probably check to see if the error is recoverable or transient.
logger.Warn("Error occurred during request, retrying...", e);
}
}
if (response != null)
{
if (response.IsSuccessStatusCode)
{
return(response);
}
else
{
logger.Debug($"Failed Response: {response.ToString()}");
bool isRetryable = isRetryableHTTPCode((int)response.StatusCode);
if (!isRetryable)
{
// No need to keep retrying, stop here
return(response);
}
}
}
else
{
logger.Info("Response returned was null.");
}
requestMessage.RequestUri = updater.Update();
logger.Debug($"Sleep {backOffInSec} seconds and then retry the request");
Thread.Sleep(backOffInSec * 1000);
totalRetryTime += backOffInSec;
backOffInSec = backOffInSec >= maxDefaultBackoff ?
maxDefaultBackoff : backOffInSec * 2;
if (totalRetryTime + backOffInSec > restTimeout.TotalSeconds)
{
// No need to wait more than necessary if it can be avoided.
// If the rest timeout will be reached before the next back-off,
// use a smaller one to give the Rest request a chance to timeout early
backOffInSec = Math.Max(1, (int)restTimeout.TotalSeconds - totalRetryTime - 1);
}
}
}
protected override async Task <HttpResponseMessage> SendAsync(HttpRequestMessage requestMessage,
CancellationToken cancellationToken)
{
HttpResponseMessage response = null;
int backOffInSec = 1;
TimeSpan httpTimeout = (TimeSpan)requestMessage.Properties["TIMEOUT_PER_HTTP_REQUEST"];
CancellationTokenSource childCts = null;
UriUpdater updater = new UriUpdater(requestMessage.RequestUri);
while (true)
{
try
{
childCts = null;
if (!httpTimeout.Equals(Timeout.InfiniteTimeSpan))
{
childCts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
childCts.CancelAfter(httpTimeout);
}
response = await base.SendAsync(requestMessage, childCts == null?
cancellationToken : childCts.Token).ConfigureAwait(false);
}
catch (Exception e)
{
if (cancellationToken.IsCancellationRequested)
{
logger.Debug("SF rest request timeout.");
cancellationToken.ThrowIfCancellationRequested();
}
else if (childCts != null && childCts.Token.IsCancellationRequested)
{
logger.Warn("Http request timeout. Retry the request");
}
else
{
//TODO: Should probably check to see if the error is recoverable or transient.
logger.Warn("Error occurred during request, retrying...", e);
}
}
if (response != null)
{
if (response.IsSuccessStatusCode)
{
return(response);
}
logger.Debug($"Failed Response: {response.ToString()}");
}
else
{
logger.Info("Response returned was null.");
}
requestMessage.RequestUri = updater.Update();
logger.Debug($"Sleep {backOffInSec} seconds and then retry the request");
Thread.Sleep(backOffInSec * 1000);
backOffInSec = backOffInSec >= 16 ? 16 : backOffInSec * 2;
}
}