internal static BreakerState ConfigureCircuitBreaker(IDurableEntityContext context, ILogger log)
{
string circuitBreakerId = context.EntityKey;
log?.LogCircuitBreakerMessage(circuitBreakerId, $"Setting configuration for circuit-breaker {circuitBreakerId}.");
// Intentionally no defaults - users should consciously decide what tolerances suit the operations invoked through the circuit-breaker.
TimeSpan breakDuration = XmlConvert.ToTimeSpan(GetCircuitConfiguration(circuitBreakerId, "BreakDuration"));
int maxConsecutiveFailures = Convert.ToInt32(GetCircuitConfiguration(circuitBreakerId, "MaxConsecutiveFailures"));
var breakerState = new BreakerState
{
CircuitState = CircuitState.Closed,
BrokenUntil = DateTime.MinValue,
ConsecutiveFailureCount = 0,
MaxConsecutiveFailures = maxConsecutiveFailures,
BreakDuration = breakDuration
};
if (breakerState.BreakDuration <= TimeSpan.Zero)
{
throw new InvalidOperationException($"Circuit-breaker {circuitBreakerId} must be configured with a positive break-duration.");
}
if (breakerState.MaxConsecutiveFailures <= 0)
{
throw new InvalidOperationException($"Circuit-breaker {circuitBreakerId} must be configured with a max number of consecutive failures greater than or equal to 1.");
}
context.SetState(breakerState);
return(breakerState);
}
private static bool IsHalfOpen(BreakerState breakerState)
{
return(breakerState.CircuitState == CircuitState.HalfOpen ||
breakerState.CircuitState == CircuitState.Open && DateTime.UtcNow > breakerState.BrokenUntil);
}