public RateLimitResult Process(ClientRequestIdentity clientRequestIdentity, RateLimitPolicy rateLimitPolicy, CancellationToken cancellationToken)
{
if (clientRequestIdentity == null)
{
throw new ArgumentNullException(nameof(clientRequestIdentity));
}
if (rateLimitPolicy == null)
{
return(RateLimitResult.NoLimit("no rate limit policy."));
}
if (rateLimitPolicy.ClientIsRequired && string.IsNullOrWhiteSpace(clientRequestIdentity.ClientId))
{
return(RateLimitResult.Limited("client id is required."));
}
if (rateLimitPolicy.IsWhitelisted(clientRequestIdentity, out RateLimitNameListPolicyMatchedResult result))
{
return(RateLimitResult.NoLimit(result.ToString()));
}
var matchedRules = rateLimitPolicy.GetMatchedRules(clientRequestIdentity);
if (matchedRules != null && matchedRules.Any())
{
lock (o_lock)
{
var rulesDict = new Dictionary <string, Tuple <RateLimitRule, RateLimitCounter> >();
foreach (var rule in matchedRules)
{
if (rule.Limit > 0)
{
var counterKey = ComputeCounterKey(rule);
var counter = GetCounter(counterKey, rule);
// check if key expired
if (counter.Timestamp + rule.PeriodTimespan.Value < DateTime.UtcNow)
{
continue;
}
// check if limit is reached
if (counter.Count > rule.Limit)
{
return(RateLimitResult.Limited(rule.ToString()));
}
rulesDict.Add(counterKey, Tuple.Create(rule, counter));
}
else
{
return(RateLimitResult.Limited(rule.ToString()));
}
}
if (rulesDict.Any())
{
foreach (var item in rulesDict)
{
_rateLimitCounterHandler.Set(item.Key, item.Value.Item2, item.Value.Item1.PeriodTimespan.Value);
}
}
}
}
return(RateLimitResult.Default);
}