private static TimeSpan CalculateExpirationTime(ThrottlingPeriod period)
{
switch (period)
{
case ThrottlingPeriod.Second:
return(TimeSpan.FromSeconds(1));
case ThrottlingPeriod.Minute:
return(TimeSpan.FromMinutes(1));
case ThrottlingPeriod.Hour:
return(TimeSpan.FromHours(1));
case ThrottlingPeriod.Day:
return(TimeSpan.FromDays(1));
default:
throw new ArgumentException(period.ToString());
}
}
private Response CheckThrottlingLimitHook(
NancyContext context,
ThrottlingProperties propertiesSet,
ThrottlingPeriod period,
int requestCountLimit,
Func <NancyContext, bool> checkIf = null,
Func <NancyContext, bool> skipIf = null,
params string[] requestKeys)
{
if (checkIf != null && !checkIf(context))
{
return(null);
}
if (skipIf != null && skipIf(context))
{
return(null);
}
var key = BuildRequestKey(propertiesSet, period, context, requestKeys);
var expirationTime = CalculateExpirationTime(period);
var counterValue = IncrementCounter(key, expirationTime);
if (IsLimitExceeded(requestCountLimit, counterValue))
{
if (IsNeedToLog(requestCountLimit, counterValue))
{
logger.Error($"Flood detected ({counterValue} in {period.ToString()} allowed {requestCountLimit})" +
$" on path: {context?.Request?.Path}" +
$" ip: {context?.GetClientHost()}");
}
return(new Response
{
StatusCode = HttpStatusCode.TooManyRequests
});
}
return(null);
}
