TransientFailure-SQL-TestHarness.cs

void Main()
{
	var policy = Policy
		   .Handle<TimeoutException>()
		   .Or<SqlException>(ex => (new[] { 40613, 40501, 40197, 10929, 10928, 10060, 10054, 10053, 233, 64, 20 }).Contains(ex.Number))
		   .WaitAndRetry(5, retryAttempt => TimeSpan.FromSeconds(Math.Pow(2, retryAttempt) / 2), 
		   (ex, count) =>
		   {
		   	count.Dump();
		   		//log
		   });
	var test = new SqlConnFailureTester();
	
	policy.Execute(() => test.ThrowsATransientError().Dump());
}

public class SqlConnFailureTester
{
	private int FailureTriggered { get; set;} = 0;
	
	public string ThrowsATimeoutError()
	{
		if(FailureTriggered > 0) return $"Success after {FailureTriggered} failures";
		FailureTriggered++;
		throw new TimeoutException();
	}

	public string ThrowsATransientError()
	{
		if(FailureTriggered > 0)  return $"Success after {FailureTriggered} failures";
		FailureTriggered++;
		throw CreateSqlException(20);
	}
	
	private SqlException CreateSqlException(int number)
	{
		var collectionConstructor = typeof(SqlErrorCollection).GetConstructor(BindingFlags.NonPublic | BindingFlags.Instance, null, new Type[0], null);
		var addMethod = typeof(SqlErrorCollection).GetMethod("Add", BindingFlags.NonPublic | BindingFlags.Instance);
		var errorCollection = (SqlErrorCollection)collectionConstructor.Invoke(null);
		var errorConstructor = typeof(SqlError).GetConstructor(BindingFlags.NonPublic | BindingFlags.Instance, null, new[]
		{
		  typeof (int), typeof (byte), typeof (byte), typeof (string), typeof(string), typeof (string),
		  typeof (int), typeof (uint)
		}, null);

		var error = errorConstructor.Invoke(new object[] { number, (byte)0, (byte)0, "server", "errMsg", "proccedure", 100, (uint)0 });
		addMethod.Invoke(errorCollection, new[] { error });

		var constructor = typeof(SqlException).GetConstructor(BindingFlags.NonPublic | BindingFlags.Instance, null, new[]
		{
			typeof(string), typeof(SqlErrorCollection), typeof(Exception), typeof(Guid)
		}, null);

		return (SqlException)constructor.Invoke(new object[] { "Error message", errorCollection, new DataException(), Guid.NewGuid() });
	}
}