retry

Documentation

Index

• func Do[T any](ctx context.Context, maxAttempts int, strategy Strategy, op func() (T, error)) (T, error)
• func Do0(ctx context.Context, maxAttempts int, strategy Strategy, op func() error) error
• func Do2[T, U any](ctx context.Context, maxAttempts int, strategy Strategy, ...) (T, U, error)
• type ErrFailedPermanently
  • func (e *ErrFailedPermanently) Error() string
  • func (e *ErrFailedPermanently) Unwrap() error
• type ExponentialStrategy
  • func (e *ExponentialStrategy) Duration(attempt int) time.Duration
• type FixedStrategy
  • func (f *FixedStrategy) Duration(attempt int) time.Duration
• type Strategy
  • func Exponential() Strategy
  • func Fixed(dur time.Duration) Strategy

Functions

func Do

func Do[T any](ctx context.Context, maxAttempts int, strategy Strategy, op func() (T, error)) (T, error)

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

func Do0

func Do0(ctx context.Context, maxAttempts int, strategy Strategy, op func() error) error

Do0 is similar to Do and Do2, execept that `op` only returns an error

func Do2

func Do2[T, U any](ctx context.Context, maxAttempts int, strategy Strategy, op func() (T, U, error)) (T, U, 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

func (*ErrFailedPermanently) Unwrap

func (e *ErrFailedPermanently) Unwrap() error

type ExponentialStrategy

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

	// Max is the maximum amount of time to wait between attempts.
	Max time.Duration

	// MaxJitter is the maximum amount of random jitter to insert between attempts.
	// Jitter is added on top of the maximum, if the maximum is reached.
	MaxJitter time.Duration
}

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

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 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