internal async Task <bool> GetShouldReplaceDeadSessionOrThrowIfNoRetryAsync(
QldbTransactionException qte,
T currentSession,
int retryAttempt,
RetryPolicy retryPolicy,
CancellationToken token)
{
bool replaceDeadSession = this.GetIsSessionDeadAndThrowIfNoRetry(
qte,
currentSession,
retryPolicy.MaxRetries,
retryAttempt);
try
{
var backoffDelay = retryPolicy.BackoffStrategy.CalculateDelay(
new RetryPolicyContext(retryAttempt, qte.InnerException));
await Task.Delay(backoffDelay, token);
}
catch (Exception)
{
// Safeguard against semaphore leak if parameter actions throw exceptions.
if (replaceDeadSession)
{
this.poolPermits.Release();
}
throw;
}
return(replaceDeadSession);
}
internal bool GetShouldReplaceDeadSessionOrThrowIfNoRetry(
QldbTransactionException qte,
T currentSession,
int retryAttempt,
RetryPolicy retryPolicy,
Action <int> retryAction)
{
bool replaceDeadSession = this.GetIsSessionDeadAndThrowIfNoRetry(
qte,
currentSession,
retryPolicy.MaxRetries,
retryAttempt);
try
{
retryAction?.Invoke(retryAttempt);
Thread.Sleep(retryPolicy.BackoffStrategy.CalculateDelay(
new RetryPolicyContext(retryAttempt, qte.InnerException)));
}
catch (Exception)
{
// Safeguard against semaphore leak if parameter actions throw exceptions.
if (replaceDeadSession)
{
this.poolPermits.Release();
}
throw;
}
return(replaceDeadSession);
}
private bool GetIsSessionDeadAndThrowIfNoRetry(
QldbTransactionException qte,
T currentSession,
int maxRetries,
int retryAttempt)
{
if (qte is RetriableException)
{
// Always retry on the first attempt if failure was caused by a stale session in the pool.
if (qte.InnerException is InvalidSessionException && retryAttempt == 1)
{
this.Logger.LogDebug("Initial session received from pool invalid. Retrying...");
return(true);
}
// Normal retry logic.
if (retryAttempt > maxRetries)
{
if (qte.IsSessionAlive)
{
this.ReleaseSession(currentSession);
}
else
{
this.poolPermits.Release();
}
throw qte.InnerException;
}
this.Logger.LogInformation("A recoverable error has occurred. Attempting retry #{}.", retryAttempt);
this.Logger.LogDebug(
"Errored Transaction ID: {}. Error cause: {}",
qte.TransactionId,
qte.InnerException.ToString());
if (qte.IsSessionAlive)
{
this.Logger.LogDebug("Retrying with a different session...");
this.ReleaseSession(currentSession);
}
else
{
this.Logger.LogDebug("Replacing invalid session...");
}
return(!qte.IsSessionAlive);
}
else
{
if (qte.IsSessionAlive)
{
this.ReleaseSession(currentSession);
}
else
{
this.poolPermits.Release();
}
throw qte.InnerException;
}
}
