public void TestDecodeThrottlingReasonCode()
{
SqlError err = FakeSqlExceptionGenerator.GenerateFakeSqlError(ThrottlingCondition.ThrottlingErrorNumber, Resources.SampleThrottlingErrorMsg);
ThrottlingCondition condition = ThrottlingCondition.FromError(err);
Assert.AreEqual(ThrottlingMode.RejectAll, condition.ThrottlingMode, "Unexpected throttling mode.");
ThrottlingType throttlingType = condition.ThrottledResources.Where(x => x.Item1 == ThrottledResourceType.Cpu).Select(x => x.Item2).FirstOrDefault();
Assert.AreEqual(ThrottlingType.Hard, throttlingType, "Unexpected throttling type.");
}
[Ignore] // REVIEW - Test will continue throwing the exception so the action will eventually run out of retry attempts
public void TestThrottlingConditionSimulation()
{
// Instantiate a retry policy capable of detecting transient faults that are specific to SQL Database. Use the default retry count.
RetryPolicy retryPolicy = new RetryPolicy <SqlDatabaseTransientErrorDetectionStrategy>(RetryStrategy.DefaultClientRetryCount);
// Register a custom event handler that will be invoked by the policy whenever a retry condition is encountered.
retryPolicy.Retrying += (sender, args) =>
{
// Log a warning message to indicate that a retry loop kicked in.
Trace.TraceWarning("Retry condition encountered. Reason: {0} (retry count: {1}, retry delay: {2})", args.LastException.Message, args.CurrentRetryCount, args.Delay);
// Make sure we are dealing with a SQL exception.
if (args.LastException is SqlException sqlException)
{
// Parse the exception to find out whether it is indicative of any throttling conditions.
ThrottlingCondition throttlingCondition = ThrottlingCondition.FromException(sqlException);
// Verify whether throttling condition were detected.
if (!throttlingCondition.IsUnknown)
{
// Log a further warning message with details on throttling conditions encountered.
Trace.TraceWarning("Throttling condition detected. Details: {0}", throttlingCondition);
}
}
};
// Invoke a database operation or set of database operations against SQL Database.
retryPolicy.ExecuteAction(() =>
{
// Open a connection, execute a SQL query or stored procedure, perform any kind of database operations.
// ...
SqlException sqlEx = FakeSqlExceptionGenerator.GenerateFakeSqlException(ThrottlingCondition.ThrottlingErrorNumber, Resources.SampleThrottlingErrorMsg);
throw sqlEx;
});
}
