backoff

Documentation

Index

• func Do(maxAttempts int, strategy Strategy, op Operation) error
• func DoCtx(ctx context.Context, maxAttempts int, strategy Strategy, op Operation) error
• type ErrFailedPermanently
  • func (e *ErrFailedPermanently) Error() string
• type ExponentialStrategy
  • func (e *ExponentialStrategy) Duration(attempt int) time.Duration
• type FixedStrategy
  • func (f *FixedStrategy) Duration(attempt int) time.Duration
• type Operation
• type Strategy
  • func Exponential() Strategy
  • func Fixed(dur time.Duration) Strategy

Functions

func Do

func Do(maxAttempts int, strategy Strategy, op Operation) error

Do performs the provided Operation up to maxAttempts times with delays in between each retry according to the provided Strategy.

func DoCtx

func DoCtx(ctx context.Context, maxAttempts int, strategy Strategy, op Operation) error

Types

type ErrFailedPermanently

type ErrFailedPermanently struct {
	LastErr error
	// contains filtered or unexported fields
}

ErrFailedPermanently is an error raised by Do when the underlying Operation has been retried maxAttempts times.

func (*ErrFailedPermanently) Error

func (e *ErrFailedPermanently) Error() string

type ExponentialStrategy

type ExponentialStrategy struct {
	// Min is the minimum amount of time to wait between attempts in ms.
	Min float64

	// Max is the maximum amount of time to wait between attempts in ms.
	Max float64

	// MaxJitter is the maximum amount of random jitter to insert between
	// attempts in ms.
	MaxJitter int
}

ExponentialStrategy performs exponential backoff. The exponential backoff function is min(e.Min + (2^attempt * 1000) + randBetween(0, e.MaxJitter), e.Max)

func (*ExponentialStrategy) Duration

func (e *ExponentialStrategy) Duration(attempt int) time.Duration

type FixedStrategy

type FixedStrategy struct {
	Dur time.Duration
}

func (*FixedStrategy) Duration

func (f *FixedStrategy) Duration(attempt int) time.Duration

type Operation

type Operation func() error

Operation represents an operation that will be retried based on some backoff strategy if it fails.

type Strategy

type Strategy interface {
	// Duration returns how long to wait for a given retry attempt.
	Duration(attempt int) time.Duration
}

Strategy is used to calculate how long a particular Operation should wait between attempts.

func Exponential

func Exponential() Strategy

func Fixed

func Fixed(dur time.Duration) Strategy