retry

Documentation

Index

• func Do(fn func(attempt int) (shouldRetry bool, err error), opts ...Option) error
• func DoTemporaryError(fn func(attempt int) error, opts ...Option) error
• func IsTemporaryError(err error) bool
• func TemporaryError(err error) error
• func Wrap[T, A any](fn func(context.Context, A) (T, error), attempts int, backoff time.Duration) func(context.Context, A) (T, error)
• func Wrap2[T, A, B any](fn func(context.Context, A, B) (T, error), attempts int, backoff time.Duration) func(context.Context, A, B) (T, error)
• type DoTempFunc
• type Option
  • func Context(ctx context.Context) Option
  • func FibBackoff(d time.Duration) Option
  • func Limit(n int) Option
  • func Log(ctx context.Context) Option

Functions

func Do

func Do(fn func(attempt int) (shouldRetry bool, err error), opts ...Option) error

Do will retry the given DoFunc until it or an option returns false. The last returned error value (can be nil) of fn will be returned.

fn will be passed the current attempt number (starting with 0).

func DoTemporaryError

func DoTemporaryError(fn func(attempt int) error, opts ...Option) error

DoTemporaryError will retry as long as the error returned from fn is temporary as defined by IsTemporaryError.

func IsTemporaryError

func IsTemporaryError(err error) bool

IsTemporaryError will determine if an error is temporary, and thus the action can/should be retried.

func TemporaryError

func TemporaryError(err error) error

TemporaryError returns an error that will always be classified as temporary.

func Wrap

func Wrap[T, A any](fn func(context.Context, A) (T, error), attempts int, backoff time.Duration) func(context.Context, A) (T, error)

Wrap will wrap a single-argument function (excl. context) with retry logic.

func Wrap2

func Wrap2[T, A, B any](fn func(context.Context, A, B) (T, error), attempts int, backoff time.Duration) func(context.Context, A, B) (T, error)

Wrap2 will wrap a two-argument function (excl. context) with retry logic.

Types

type DoTempFunc

type DoTempFunc func(int) error

DoTempFunc is a simplified version of DoFunc that just returns an error value.

type Option

type Option func(int, error) bool

An Option takes the attempt number and the last error value (can be nil) and should indicate if a retry should be made.

func Context

func Context(ctx context.Context) Option

Context will allow retry to continue until the context is canceled.

func FibBackoff

func FibBackoff(d time.Duration) Option

FibBackoff will Sleep for f(n) * Duration (+/- 50ms) before each attempt, where f(n) is the value from the Fibonacci sequence for the nth attempt. There is no delay for the first attempt (n=0).

func Limit

func Limit(n int) Option

Limit will set the max number of retry attempts (including the initial attempt).

func Log

func Log(ctx context.Context) Option

Log will log all errors between retries returned from the DoFunc at Debug level. The final error, if any, is not logged.