Line data    Source code

       1              : #ifndef NETWORKRETRYPOLICY_H
       2              : #define NETWORKRETRYPOLICY_H
       3              : 
       4              : #include <QObject>
       5              : #include <QNetworkReply>
       6              : 
       7              : /*!
       8              :     \brief Defines retry behavior.
       9              :  */
      10              : class NetworkRetryPolicy
      11              : {
      12              : public:
      13              :     enum BackoffStrategy {
      14              :         Linear,       // 1s, 2s, 3s, 4s...
      15              :         Exponential,  // 1s, 2s, 4s, 8s...
      16              :         Fibonacci,    // 1s, 2s, 3s, 5s, 8s...
      17              :         Fixed         // Same delay every time
      18              :     };
      19              : 
      20              :     NetworkRetryPolicy();
      21              : 
      22              : 
      23              :     NetworkRetryPolicy(int maxRetries, int baseDelay, BackoffStrategy strategy, int maxDelay = 60000);
      24              : 
      25              : 
      26              :     static NetworkRetryPolicy forFeedUpdate();
      27              :     static NetworkRetryPolicy forFavicon();
      28              :     static NetworkRetryPolicy forCritical();
      29              :     static NetworkRetryPolicy noRetry();
      30              : 
      31              :     /*!
      32              :         \brief Whether or not we should try, try again.
      33              :      */
      34              :     bool isRetryable(QNetworkReply::NetworkError error) const;
      35              : 
      36              :     /*!
      37              :         \brief Returns retry delay.
      38              :      */
      39              :     int calculateDelay(int attemptNumber) const;
      40              : 
      41              :     /*!
      42              :         \brief Returns max retries.
      43              :      */
      44            5 :     int maxRetries() const { return maxNumRetries; }
      45              : 
      46              :     /*!
      47              :         \brief Check if retries should continue or give up.
      48              :      */
      49           32 :     bool shouldRetry(int currentAttempt) const { return currentAttempt < maxNumRetries; }
      50              : 
      51              :     /*!
      52              :         \brief Sets if we will retry on timeout errors.
      53              :      */
      54            1 :     void setRetryOnTimeout(bool retry) { shouldRetryOnTimeout = retry; }
      55              : 
      56              :     /*!
      57              :         \brief Sets if we will retry on DNS errors.
      58              :      */
      59              :     void setRetryOnDnsFailure(bool retry) { shouldRetryOnDnsFailure = retry; }
      60              : 
      61              :     /*!
      62              :         \brief Sets if we will retry on connection refused.
      63              :      */
      64              :     void setRetryOnConnectionRefused(bool retry) { shouldRetryOnConnectionRefused = retry; }
      65              : 
      66              : private:
      67              :     int maxNumRetries;
      68              :     int defaultDelayMs;
      69              :     int maxDelayMs;
      70              :     BackoffStrategy strategy;
      71              : 
      72              :     bool shouldRetryOnTimeout;
      73              :     bool shouldRetryOnDnsFailure;
      74              :     bool shouldRetryOnConnectionRefused;
      75              :     bool shouldRetryOnServerError;
      76              : };
      77              : 
      78              : #endif // NETWORKRETRYPOLICY_H