/// <summary>
/// Sends an HTTP request to the inner handler to send to the server as an asynchronous operation.
/// </summary>
/// <param name="request">The HTTP request message to send to the server.</param>
/// <param name="cancellationToken">A cancellation token to cancel operation.</param>
/// <returns>The task object representing the asynchronous operation.</returns>
protected override async Task <HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
this.RetryPolicy.Retrying += (sender, args) => Retrying?.Invoke(sender, args);
HttpResponseMessage responseMessage = null;
try
{
await this.RetryPolicy.ExecuteAsync(async() =>
{
responseMessage = await base.SendAsync(request, cancellationToken).ConfigureAwait(false);
if (!responseMessage.IsSuccessStatusCode)
{
// dispose the message unless we have stopped retrying
this.Retrying += (sender, args) =>
{
if (responseMessage != null)
{
responseMessage.Dispose();
responseMessage = null;
}
};
throw new HttpRequestWithStatusException(responseMessage);
}
return(responseMessage);
}, cancellationToken).ConfigureAwait(false);
return(responseMessage);
}
catch
{
if (responseMessage != null)
{
return(responseMessage);
}
else
{
throw;
}
}
finally
{
if (Retrying != null)
{
foreach (EventHandler <RetryingEventArgs> d in Retrying.GetInvocationList())
{
Retrying -= d;
}
}
}
}
private void ApplyRetryingEvent(object sender, SqlRetryLogicBase retryLogic, TimeSpan intervalTime, List <Exception> exceptions, Exception lastException)
{
string methodName = MethodBase.GetCurrentMethod().Name;
if (Retrying != null)
{
var retryEventArgs = new SqlRetryingEventArgs(retryLogic.Current, intervalTime, exceptions);
SqlClientEventSource.Log.TryTraceEvent("<sc.{0}.{1}|INFO> Running the retrying event.", TypeName, methodName);
Retrying?.Invoke(sender, retryEventArgs);
if (retryEventArgs.Cancel)
{
SqlClientEventSource.Log.TryTraceEvent("<sc.{0}.{1}|INFO> Retry attempt cancelled (current retry number = {2}).",
TypeName, methodName, retryLogic.Current);
throw CreateException(exceptions, retryLogic, true);
}
}
SqlClientEventSource.Log.TryTraceEvent("<sc.{0}.{1}|INFO> Wait '{2}' and run the action for retry number {3}.",
TypeName, methodName, intervalTime, retryLogic.Current);
}
/// <summary>
/// Notifies the subscribers whenever a retry condition is encountered.
/// </summary>
/// <param name="retryCount">The current retry attempt count.</param>
/// <param name="lastError">The exception that caused the retry conditions to occur.</param>
/// <param name="delay">The delay that indicates how long the current thread will be suspended before the next iteration is invoked.</param>
protected virtual void OnRetrying(int retryCount, Exception lastError, TimeSpan delay)
{
Retrying?.Invoke(this, new RetryingEventArgs(retryCount, delay, lastError));
}