AdaptiveRetryStrategy.h

 
#pragma once
 
#include <aws/core/Core_EXPORTS.h>
#include <aws/core/client/RetryStrategy.h>
#include <aws/core/utils/DateTime.h>
 
namespace Aws
{
namespace Client
{
 
class AWS_CORE_API RetryTokenBucket
{
public:
    RetryTokenBucket() = default;
 
    bool Acquire(size_t amount = 1, bool fastFail = false);
 
    void UpdateClientSendingRate(bool throttlingResponse, const Aws::Utils::DateTime& now = Aws::Utils::DateTime::Now());
 
protected:
    RetryTokenBucket(double fillRate, double maxCapacity, double currentCapacity,
                     const Aws::Utils::DateTime& lastTimestamp, double measuredTxRate, double lastTxRateBucket,
                     size_t requestCount, bool enabled, double lastMaxRate, const Aws::Utils::DateTime& lastThrottleTime);
 
    void UpdateMeasuredRate(const Aws::Utils::DateTime& now = Aws::Utils::DateTime::Now());
 
    void Enable();
 
    void UpdateRate(double newRps, const Aws::Utils::DateTime& now = Aws::Utils::DateTime::Now());
 
    void Refill(const Aws::Utils::DateTime& now = Aws::Utils::DateTime::Now());
 
    double CalculateTimeWindow() const;
 
    double CUBICSuccess(const Aws::Utils::DateTime& timestamp, const double timeWindow) const;
 
    double CUBICThrottle(const double rateToUse) const;
 
    // The rate at which token are replenished.
    double m_fillRate = 0.0;
    // The maximum capacity allowed in the token bucket.
    double m_maxCapacity = 0.0;
    // The current capacity of the token bucket.
    double m_currentCapacity = 0.0;
    // The last time the token bucket was refilled.
    Aws::Utils::DateTime m_lastTimestamp;
    // The smoothed rate which tokens are being retrieved.
    double m_measuredTxRate = 0.0;
    // The last half second time bucket used.
    double m_lastTxRateBucket = 0.0;
    // The number of requests seen within the current time bucket.
    size_t m_requestCount = 0;
    // Boolean indicating if the token bucket is enabled.
    bool m_enabled = false;
    // The maximum rate when the client was last throttled.
    double m_lastMaxRate = 0.0;
    // The last time when the client was throttled.
    Aws::Utils::DateTime m_lastThrottleTime;
 
    // TokenBucket's mutex to synchronize read/write operations
    std::recursive_mutex m_mutex;
};
 
class AWS_CORE_API AdaptiveRetryStrategy : public StandardRetryStrategy
{
public:
    AdaptiveRetryStrategy(long maxAttempts = 3);
    AdaptiveRetryStrategy(std::shared_ptr<RetryQuotaContainer> retryQuotaContainer, long maxAttempts = 3);
 
    virtual bool HasSendToken() override;
 
    virtual void RequestBookkeeping(const HttpResponseOutcome& httpResponseOutcome) override;
    virtual void RequestBookkeeping(const HttpResponseOutcome& httpResponseOutcome, const AWSError<CoreErrors>& lastError) override;
 
    const char* GetStrategyName() const override { return "adaptive";}
 
protected:
    RetryTokenBucket m_retryTokenBucket;
    bool m_fastFail = false;
 
private:
    static bool IsThrottlingResponse(const HttpResponseOutcome& httpResponseOutcome);
};
 
} // namespace Client
} // namespace Aws