internal string ComputeThrottleKey(RequestIdentity requestIdentity, RateLimitPeriod period)
{
using (var ms = new MemoryStream())
using (var sw = new StreamWriter(ms, Encoding.UTF8))
{
sw.Write(ThrottleManager.GetThrottleKey());
if (Policy.IpThrottling)
{
sw.Write(requestIdentity.ClientIp);
}
if (Policy.ClientThrottling)
{
sw.Write(requestIdentity.ClientKey);
}
if (Policy.EndpointThrottling)
{
sw.Write(requestIdentity.Endpoint);
}
sw.Write(period);
sw.Flush();
ms.Position = 0;
using (var algorithm = new SHA1Managed())
{
var hash = algorithm.ComputeHash(ms);
return(Convert.ToBase64String(hash));
}
}
}
internal TimeSpan GetSuspendSpanFromPeriod(RateLimitPeriod rateLimitPeriod, TimeSpan timeSpan, long suspendTime)
{
switch (rateLimitPeriod)
{
case RateLimitPeriod.Second:
timeSpan = (suspendTime > 1) ? TimeSpan.FromSeconds(suspendTime) : timeSpan;
break;
case RateLimitPeriod.Minute:
timeSpan = (suspendTime > 60) ? TimeSpan.FromSeconds(suspendTime) : (timeSpan + TimeSpan.FromSeconds(suspendTime));
break;
case RateLimitPeriod.Hour:
timeSpan += TimeSpan.FromSeconds(suspendTime);
break;
case RateLimitPeriod.Day:
timeSpan += TimeSpan.FromSeconds(suspendTime);
break;
case RateLimitPeriod.Week:
timeSpan += TimeSpan.FromSeconds(suspendTime);
break;
}
return(timeSpan);
}
private string RetryAfterFrom(DateTime timestamp, RateLimitPeriod period)
{
var secondsPast = Convert.ToInt32((DateTime.UtcNow - timestamp).TotalSeconds);
var retryAfter = 1;
switch (period)
{
case RateLimitPeriod.Minute:
retryAfter = 60;
break;
case RateLimitPeriod.Hour:
retryAfter = 60 * 60;
break;
case RateLimitPeriod.Day:
retryAfter = 60 * 60 * 24;
break;
case RateLimitPeriod.Week:
retryAfter = 60 * 60 * 24 * 7;
break;
}
retryAfter = retryAfter > 1 ? retryAfter - secondsPast : 1;
return(retryAfter.ToString(CultureInfo.InvariantCulture));
}
internal string RetryAfterFrom(DateTime timestamp, long suspendTime, RateLimitPeriod period)
{
var secondsPast = Convert.ToInt32((DateTime.UtcNow - timestamp).TotalSeconds);
var retryAfter = 1;
switch (period)
{
case RateLimitPeriod.Second:
retryAfter = (suspendTime > 1) ? (int)suspendTime : 1;
break;
case RateLimitPeriod.Minute:
retryAfter = (suspendTime > 60) ? (int)suspendTime : (60 + (int)suspendTime);
break;
case RateLimitPeriod.Hour:
retryAfter = (60 * 60) + (int)suspendTime;
break;
case RateLimitPeriod.Day:
retryAfter = (60 * 60 * 24) + (int)suspendTime;
break;
case RateLimitPeriod.Week:
retryAfter = (60 * 60 * 24 * 7) + (int)suspendTime;
break;
}
retryAfter = retryAfter > 1 ? retryAfter - secondsPast : 1;
return(retryAfter.ToString(System.Globalization.CultureInfo.InvariantCulture));
}
internal string ComputeThrottleKey(RequestIdentity requestIdentity, RateLimitPeriod period)
{
var keyValues = new List <string>()
{
ThrottleManager.GetThrottleKey()
};
if (Policy.IpThrottling)
{
keyValues.Add(requestIdentity.ClientIp);
}
if (Policy.ClientThrottling)
{
keyValues.Add(requestIdentity.ClientKey);
}
if (Policy.EndpointThrottling)
{
keyValues.Add(requestIdentity.Endpoint);
}
keyValues.Add(period.ToString());
var id = string.Join("_", keyValues);
var idBytes = Encoding.UTF8.GetBytes(id);
var hashBytes = new System.Security.Cryptography.SHA1Managed().ComputeHash(idBytes);
var hex = BitConverter.ToString(hashBytes).Replace("-", string.Empty);
return(hex);
}
public long GetLimit(RateLimitPeriod period)
{
switch (period)
{
case RateLimitPeriod.Second:
return(PerSecond);
case RateLimitPeriod.Minute:
return(PerMinute);
case RateLimitPeriod.Hour:
return(PerHour);
case RateLimitPeriod.Day:
return(PerDay);
case RateLimitPeriod.Week:
return(PerWeek);
case RateLimitPeriod.FiveSecond:
return(PerFiveSecond);
case RateLimitPeriod.TenSecond:
return(PerTenSecond);
case RateLimitPeriod.FifteenSecond:
return(PerFifteenSecond);
default:
return(PerSecond);
}
}
internal TimeSpan GetTimeSpanFromPeriod(RateLimitPeriod rateLimitPeriod)
{
var timeSpan = TimeSpan.FromSeconds(1);
switch (rateLimitPeriod)
{
case RateLimitPeriod.Second:
timeSpan = TimeSpan.FromSeconds(1);
break;
case RateLimitPeriod.Minute:
timeSpan = TimeSpan.FromMinutes(1);
break;
case RateLimitPeriod.Hour:
timeSpan = TimeSpan.FromHours(1);
break;
case RateLimitPeriod.Day:
timeSpan = TimeSpan.FromDays(1);
break;
case RateLimitPeriod.Week:
timeSpan = TimeSpan.FromDays(7);
break;
}
return(timeSpan);
}
internal void ApplyRules(RequestIdentity identity, TimeSpan timeSpan, RateLimitPeriod rateLimitPeriod, ref long rateLimit, ref long suspend)
{
// apply endpoint rate limits
if (Policy.EndpointRules != null)
{
var rules = Policy.EndpointRules.Where(x => identity.Endpoint.IndexOf(x.Key, 0, StringComparison.InvariantCultureIgnoreCase) != -1).ToList();
if (rules.Count > 0)
{
// get the lower limit from all applying rules
var customRate = (from r in rules let rateValue = r.Value.GetLimit(rateLimitPeriod) select rateValue).Min();
var customSuspend = (from r in rules let suspendTime = r.Value.SuspendTime select suspendTime).Max();
if (customRate > 0)
{
rateLimit = customRate;
}
if (customSuspend > 0)
{
suspend = customSuspend;
}
}
}
// apply custom rate limit for clients that will override endpoint limits
if (Policy.ClientRules?.Keys.Contains(identity.ClientKey) == true)
{
var limit = Policy.ClientRules[identity.ClientKey].GetLimit(rateLimitPeriod);
if (limit > 0)
{
rateLimit = limit;
}
var customSuspend = Policy.ClientRules[identity.ClientKey].SuspendTime;
if (customSuspend > 0)
{
suspend = customSuspend;
}
}
// enforce ip rate limit as is most specific
if (Policy.IpRules != null && ContainsIp(Policy.IpRules.Keys.ToList(), identity.ClientIp, out string ipRule))
{
var limit = Policy.IpRules[ipRule].GetLimit(rateLimitPeriod);
if (limit > 0)
{
rateLimit = limit;
}
var customSuspend = Policy.IpRules[ipRule].SuspendTime;
if (customSuspend > 0)
{
suspend = customSuspend;
}
}
}
private void ProcessQuotaExceeded(RateLimitPeriod rateLimitPeriod, long rateLimit, string retryAfter)
{
var message = !string.IsNullOrEmpty(QuotaExceededMessage)
? QuotaExceededMessage
: "API calls quota exceeded! maximum admitted {0} per {1}.";
var content = QuotaExceededContent != null
? QuotaExceededContent(rateLimit, rateLimitPeriod)
: string.Format(message, rateLimit, rateLimitPeriod);
processResult.IsPass = false;
processResult.Message = message;
processResult.Content = content;
processResult.RetryAfter = retryAfter;
processResult.StatusCode = (int)QuotaExceededResponseCode;
}
public long GetLimit(RateLimitPeriod period)
{
switch (period)
{
case RateLimitPeriod.Second:
return PerSecond;
case RateLimitPeriod.Minute:
return PerMinute;
case RateLimitPeriod.Hour:
return PerHour;
case RateLimitPeriod.Day:
return PerDay;
default:
return PerSecond;
}
}
internal ThrottleCounter ProcessRequest(TimeSpan timeSpan, RateLimitPeriod period, long rateLimit, long suspendTime, string id)
{
var throttleCounter = new ThrottleCounter()
{
Timestamp = DateTime.UtcNow,
TotalRequests = 1
};
TimeSpan suspendSpan = TimeSpan.FromSeconds(0);
// serial reads and writes
lock (ProcessLocker)
{
var entry = Repository.FirstOrDefault(id);
if (entry.HasValue)
{
var timeStamp = entry.Value.Timestamp;
if (entry.Value.TotalRequests >= rateLimit && suspendTime > 0)
{
timeSpan = GetSuspendSpanFromPeriod(period, timeSpan, suspendTime);
}
// 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 = timeStamp,
TotalRequests = totalRequests
};
}
}
// stores: id (string) - timestamp (datetime) - total (long)
Repository.Save(id, throttleCounter, timeSpan);
}
return(throttleCounter);
}
internal void ApplyRules(RequestIdentity identity, TimeSpan timeSpan, RateLimitPeriod rateLimitPeriod, ref long rateLimit)
{
// apply endpoint rate limits
if (Policy.EndpointRules != null)
{
var rules = Policy.EndpointRules.Where(x => identity.Endpoint.IndexOf(x.Key, 0, StringComparison.InvariantCultureIgnoreCase) != -1).ToList();
//var rules = Policy.EndpointRules.Where(x => Regex.IsMatch(identity.Endpoint, x.Key, RegexOptions.IgnoreCase)).ToList();
if (rules.Any())
{
// get the lower limit from all applying rules
var customRate = (from r in rules let rateValue = r.Value.GetLimit(rateLimitPeriod) select rateValue).Min();
if (customRate > 0)
{
rateLimit = customRate;
}
}
}
// apply custom rate limit for clients that will override endpoint limits
if (Policy.ClientRules != null && Policy.ClientRules.Keys.Contains(identity.ClientKey))
{
var limit = Policy.ClientRules[identity.ClientKey].GetLimit(rateLimitPeriod);
if (limit > 0)
{
rateLimit = limit;
}
}
// enforce ip rate limit as is most specific
string ipRule = null;
if (Policy.IpRules != null && ContainsIp(Policy.IpRules.Keys.ToList(), identity.ClientIp, out ipRule))
{
var limit = Policy.IpRules[ipRule].GetLimit(rateLimitPeriod);
if (limit > 0)
{
rateLimit = limit;
}
}
}
internal void ApplyRules(RequestIdentity identity, TimeSpan timeSpan, RateLimitPeriod rateLimitPeriod, ref long rateLimit)
{
// apply endpoint rate limits
if (Policy.EndpointRules != null)
{
var rules = Policy.EndpointRules.Where(x => x.Match(identity)).ToList();
if (rules.Any())
{
// get the lower limit from all applying rules
var customRate = (from r in rules let rateValue = r.limits.GetLimit(rateLimitPeriod) select rateValue).Min();
if (customRate > 0)
{
rateLimit = customRate;
}
}
}
// apply custom rate limit for clients that will override endpoint limits
if (Policy.ClientRules != null && Policy.ClientRules.Keys.Contains(identity.ClientKey))
{
var limit = Policy.ClientRules[identity.ClientKey].GetLimit(rateLimitPeriod);
if (limit > 0)
{
rateLimit = limit;
}
}
// enforce ip rate limit as is most specific
string ipRule = null;
if (Policy.IpRules != null && ContainsIp(Policy.IpRules.Keys.ToList(), identity.ClientIp, out ipRule))
{
var limit = Policy.IpRules[ipRule].GetLimit(rateLimitPeriod);
if (limit > 0)
{
rateLimit = limit;
}
}
}
internal void ApplyRules(RequestIdentity identity, TimeSpan timeSpan, RateLimitPeriod rateLimitPeriod, ref long rateLimit)
{
// apply endpoint rate limits
if (Policy.EndpointRules != null)
{
var rules = Policy.EndpointRules.Where(x => identity.EndpointWithMethod.Contains(x.Key.ToLowerInvariant())).ToList();
if (rules.Any())
{
// get the lower limit from all applying rules
var customRate = (from r in rules let rateValue = r.Value.GetLimit(rateLimitPeriod) select rateValue).Min();
if (customRate > 0)
{
rateLimit = customRate;
}
}
}
// apply custom rate limit for clients that will override endpoint limits
if (Policy.ClientRules != null && Policy.ClientRules.Keys.Contains(identity.ClientKey))
{
var limit = Policy.ClientRules[identity.ClientKey].GetLimit(rateLimitPeriod);
if (limit > 0)
{
rateLimit = limit;
}
}
// enforce ip rate limit as is most specific
string ipRule = null;
if (Policy.IpRules != null && ContainsIp(Policy.IpRules.Keys.ToList(), identity.ClientIp, out ipRule))
{
var limit = Policy.IpRules[ipRule].GetLimit(rateLimitPeriod);
if (limit > 0)
{
rateLimit = limit;
}
}
}
internal string RetryAfterFrom(DateTime timestamp, RateLimitPeriod period)
{
var secondsPast = Convert.ToInt32((DateTime.UtcNow - timestamp).TotalSeconds);
var retryAfter = 1;
switch (period)
{
case RateLimitPeriod.Minute:
retryAfter = 60;
break;
case RateLimitPeriod.Hour:
retryAfter = 60 * 60;
break;
case RateLimitPeriod.Day:
retryAfter = 60 * 60 * 24;
break;
case RateLimitPeriod.Week:
retryAfter = 60 * 60 * 24 * 7;
break;
}
retryAfter = retryAfter > 1 ? retryAfter - secondsPast : 1;
return retryAfter.ToString(System.Globalization.CultureInfo.InvariantCulture);
}
public virtual long GetLimit(RateLimitPeriod period)
{
switch (period)
{
case RateLimitPeriod.Second:
return(PerSecond);
case RateLimitPeriod.Minute:
return(PerMinute);
case RateLimitPeriod.Hour:
return(PerHour);
case RateLimitPeriod.Day:
return(PerDay);
case RateLimitPeriod.Week:
return(PerWeek);
default:
return(PerSecond);
}
}
protected virtual string ComputeThrottleKey(RequestIdentity requestIdentity, RateLimitPeriod period)
{
var keyValues = new List<string>()
{
"throttle"
};
if (Policy.IpThrottling)
keyValues.Add(requestIdentity.ClientIp);
if (Policy.ClientThrottling)
keyValues.Add(requestIdentity.ClientKey);
if (Policy.EndpointThrottling)
keyValues.Add(requestIdentity.Endpoint);
keyValues.Add(period.ToString());
var id = string.Join("_", keyValues);
var idBytes = Encoding.UTF8.GetBytes(id);
var hashBytes = new System.Security.Cryptography.SHA1Managed().ComputeHash(idBytes);
var hex = BitConverter.ToString(hashBytes).Replace("-", "");
return hex;
}
private 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 = Repository.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)
Repository.Save(id, throttleCounter, timeSpan);
}
return(throttleCounter);
}
/// <summary>
/// 节流属性注入
/// </summary>
/// <param name="maxRate"> 基于<see cref="RateLimitPeriod"/>的最大请求</param>
/// <param name="maxBurst">最大突发请求</param>
/// <param name="periodType">限制速率的周期类型</param>
public EnableThrottlingAttribute(long maxRate, long maxBurst, RateLimitPeriod periodType)
{
MaxRate = maxRate;
MaxBurst = maxBurst;
PeriodType = periodType;
}
/// <summary>
/// Initializes a new instance of the <see cref="RateQuota"/> class.
/// </summary>
/// <param name="maxRate">基于<see cref="RateLimitPeriod" />的最大请求</param>
/// <param name="maxBurst">最大突发请求</param>
/// <param name="periodType"><see cref="RateLimitPeriod" /></param>
public RateQuota(long maxRate, long maxBurst, RateLimitPeriod periodType)
{
MaxRate = maxRate;
MaxBurst = maxBurst;
PeriodType = periodType;
}
internal string ComputeThrottleKey(RequestIdentity requestIdentity, RateLimitPeriod period)
{
var keyValues = new List<string>()
{
ThrottleManager.GetThrottleKey()
};
if (Policy.IpThrottling)
{
keyValues.Add(requestIdentity.ClientIp);
}
if (Policy.ClientThrottling)
{
keyValues.Add(requestIdentity.ClientKey);
}
if (Policy.EndpointThrottling)
{
if (Policy.EndpointThrottleMethod == EndpointThrottlingMethod.Action &&
!string.IsNullOrWhiteSpace(requestIdentity.ActionName) &&
!string.IsNullOrWhiteSpace(requestIdentity.ControllerName))
{
//TODO: think of a better way to do this
keyValues.Add(requestIdentity.ControllerName + "." + requestIdentity.ActionName);
}
else if (Policy.EndpointThrottleMethod == EndpointThrottlingMethod.Url)
{
keyValues.Add(requestIdentity.Endpoint);
}
}
keyValues.Add(period.ToString());
var id = string.Join("_", keyValues);
var idBytes = Encoding.UTF8.GetBytes(id);
byte[] hashBytes;
using (var algorithm = System.Security.Cryptography.HashAlgorithm.Create("SHA1"))
{
hashBytes = algorithm.ComputeHash(idBytes);
}
var hex = BitConverter.ToString(hashBytes).Replace("-", string.Empty);
return hex;
}
internal string ComputeThrottleKey(RequestIdentity requestIdentity, RateLimitPeriod period)
{
var keyValues = new List<string>()
{
ThrottleManager.GetThrottleKey()
};
if (Policy.IpThrottling)
{
keyValues.Add(requestIdentity.ClientIp);
}
if (Policy.ClientThrottling)
{
keyValues.Add(requestIdentity.ClientKey);
}
if (Policy.EndpointThrottling)
{
keyValues.Add(requestIdentity.Endpoint);
}
keyValues.Add(period.ToString());
var id = string.Join("_", keyValues);
var idBytes = Encoding.UTF8.GetBytes(id);
byte[] hashBytes;
using (var algorithm = System.Security.Cryptography.HashAlgorithm.Create("SHA1"))
{
hashBytes = algorithm.ComputeHash(idBytes);
}
var hex = BitConverter.ToString(hashBytes).Replace("-", string.Empty);
return hex;
}
internal TimeSpan GetTimeSpanFromPeriod(RateLimitPeriod rateLimitPeriod)
{
var timeSpan = TimeSpan.FromSeconds(1);
switch (rateLimitPeriod)
{
case RateLimitPeriod.Second:
timeSpan = TimeSpan.FromSeconds(1);
break;
case RateLimitPeriod.Minute:
timeSpan = TimeSpan.FromMinutes(1);
break;
case RateLimitPeriod.Hour:
timeSpan = TimeSpan.FromHours(1);
break;
case RateLimitPeriod.Day:
timeSpan = TimeSpan.FromDays(1);
break;
case RateLimitPeriod.Week:
timeSpan = TimeSpan.FromDays(7);
break;
}
return timeSpan;
}
private 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 = Repository.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)
Repository.Save(id, throttleCounter, timeSpan);
}
return throttleCounter;
}
protected virtual string ComputeThrottleKey(RequestIdentity requestIdentity, RateLimitPeriod period)
{
return core.ComputeThrottleKey(requestIdentity, period);
}
protected virtual string ComputeThrottleKey(RequestIdentity requestIdentity, RateLimitPeriod period)
{
return(core.ComputeThrottleKey(requestIdentity, period));
}
private ThrottleCounter ProcessRequest(ThrottlePolicy throttlePolicy, RequestIndentity throttleEntry, TimeSpan timeSpan, RateLimitPeriod period, out string id)
{
var throttleCounter = new ThrottleCounter();
throttleCounter.Timestamp = DateTime.UtcNow;
throttleCounter.TotalRequests = 1;
//computed request unique id from IP, client key, url and period
id = "throttle";
if (throttlePolicy.IpThrottling)
{
if (throttlePolicy.IpWhitelist != null && throttlePolicy.IpWhitelist.Contains(throttleEntry.ClientIp))
{
return throttleCounter;
}
id += "_" + throttleEntry.ClientIp;
}
if (throttlePolicy.ClientThrottling)
{
if (throttlePolicy.ClientWhitelist != null && throttlePolicy.ClientWhitelist.Contains(throttleEntry.ClientKey))
{
return throttleCounter;
}
id += "_" + throttleEntry.ClientKey;
}
if (throttlePolicy.EndpointThrottling)
{
if (throttlePolicy.EndpointWhitelist != null && Policy.EndpointWhitelist.Any(x => throttleEntry.Endpoint.Contains(x)))
{
return throttleCounter;
}
id += "_" + throttleEntry.Endpoint;
}
id += "_" + period;
//get the hash value of the computed id
var hashId = ComputeHash(id);
//serial reads and writes
lock (_processLocker)
{
var entry = Repository.FirstOrDefault(hashId);
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)
Repository.Save(hashId, throttleCounter, timeSpan);
}
return throttleCounter;
}