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66 lines
2.1 KiB
66 lines
2.1 KiB
// Package backoff implements backoff algorithms for retrying operations. |
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// |
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// Use Retry function for retrying operations that may fail. |
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// If Retry does not meet your needs, |
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// copy/paste the function into your project and modify as you wish. |
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// |
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// There is also Ticker type similar to time.Ticker. |
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// You can use it if you need to work with channels. |
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// |
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// See Examples section below for usage examples. |
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package backoff |
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import "time" |
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// BackOff is a backoff policy for retrying an operation. |
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type BackOff interface { |
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// NextBackOff returns the duration to wait before retrying the operation, |
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// or backoff. Stop to indicate that no more retries should be made. |
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// |
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// Example usage: |
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// |
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// duration := backoff.NextBackOff(); |
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// if (duration == backoff.Stop) { |
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// // Do not retry operation. |
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// } else { |
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// // Sleep for duration and retry operation. |
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// } |
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// |
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NextBackOff() time.Duration |
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// Reset to initial state. |
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Reset() |
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} |
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// Stop indicates that no more retries should be made for use in NextBackOff(). |
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const Stop time.Duration = -1 |
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// ZeroBackOff is a fixed backoff policy whose backoff time is always zero, |
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// meaning that the operation is retried immediately without waiting, indefinitely. |
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type ZeroBackOff struct{} |
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func (b *ZeroBackOff) Reset() {} |
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func (b *ZeroBackOff) NextBackOff() time.Duration { return 0 } |
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// StopBackOff is a fixed backoff policy that always returns backoff.Stop for |
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// NextBackOff(), meaning that the operation should never be retried. |
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type StopBackOff struct{} |
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func (b *StopBackOff) Reset() {} |
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func (b *StopBackOff) NextBackOff() time.Duration { return Stop } |
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// ConstantBackOff is a backoff policy that always returns the same backoff delay. |
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// This is in contrast to an exponential backoff policy, |
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// which returns a delay that grows longer as you call NextBackOff() over and over again. |
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type ConstantBackOff struct { |
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Interval time.Duration |
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} |
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func (b *ConstantBackOff) Reset() {} |
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func (b *ConstantBackOff) NextBackOff() time.Duration { return b.Interval } |
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func NewConstantBackOff(d time.Duration) *ConstantBackOff { |
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return &ConstantBackOff{Interval: d} |
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}
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