public ThrottleLogEntry ComputeLogEntry(
string requestId,
RequestIdentity identity,
ThrottleCounter throttleCounter,
string rateLimitPeriod,
long rateLimit)
{
return(new ThrottleLogEntry
{
ClientIp = identity.ClientIp,
ClientKey = identity.ClientKey,
Endpoint = identity.Endpoint,
LogDate = DateTime.UtcNow,
RateLimit = rateLimit,
RateLimitPeriod = rateLimitPeriod,
RequestId = requestId,
StartPeriod = throttleCounter.Timestamp,
TotalRequests = throttleCounter.TotalRequests
});
}
public ThrottleCounter ProcessRequest(RequestIdentity requestIdentity, TimeSpan timeSpan, RateLimitPeriod period, out string id)
{
var throttleCounter = new ThrottleCounter()
{
Timestamp = DateTime.UtcNow,
TotalRequests = 1
};
id = ComputeThrottleKey(requestIdentity, period);
// serial reads and writes
lock (ProcessLocker)
{
var entry = ThrottleRepo.FirstOrDefault(id);
if (entry.HasValue)
{
// entry has not expired
if (entry.Value.Timestamp + timeSpan >= DateTime.UtcNow)
{
// increment request count
var totalRequests = entry.Value.TotalRequests + 1;
// deep copy
throttleCounter = new ThrottleCounter
{
Timestamp = entry.Value.Timestamp,
TotalRequests = totalRequests
};
}
}
// stores: id (string) - timestamp (datetime) - total (long)
ThrottleRepo.Save(id, throttleCounter, timeSpan);
}
return(throttleCounter);
}
/// <summary>
/// Insert or update
/// </summary>
public void Save(string id, ThrottleCounter throttleCounter, TimeSpan expirationTime)
{
var cachePolicy = CachePolicy.WithSlidingExpiration(expirationTime);
CacheManager.Set(id, throttleCounter, cachePolicy);
}