backoff

Documentation

Overview

Package backoff implements backoff timers which increases wait time on every retry, incredibly useful in distributed system timeout functionalities.

Index

• type Backoff
  • func New(ctx context.Context, cfg Config) *Backoff
  • func (b *Backoff) Err() error
  • func (b *Backoff) NextDelay() time.Duration
  • func (b *Backoff) NumRetries() int
  • func (b *Backoff) Ongoing() bool
  • func (b *Backoff) Reset()
  • func (b *Backoff) Wait()
• type Config

Types

type Backoff

type Backoff struct {
	// contains filtered or unexported fields
}

Backoff implements exponential backoff with randomized wait times.

func New

func New(ctx context.Context, cfg Config) *Backoff

New creates a Backoff object. Pass a Context that can also terminate the operation.

func (*Backoff) Err

func (b *Backoff) Err() error

Err returns the reason for terminating the backoff, or nil if it didn't terminate.

func (*Backoff) NextDelay

func (b *Backoff) NextDelay() time.Duration

func (*Backoff) NumRetries

func (b *Backoff) NumRetries() int

NumRetries returns the number of retries so far.

func (*Backoff) Ongoing

func (b *Backoff) Ongoing() bool

Ongoing returns true if caller should keep going.

func (*Backoff) Reset

func (b *Backoff) Reset()

Reset the Backoff back to its initial condition.

func (*Backoff) Wait

func (b *Backoff) Wait()

Wait sleeps for the backoff time then increases the retry count and backoff time. Returns immediately if Context is terminated.

type Config

type Config struct {
	Min        time.Duration `yaml:"min_period"`  // Start backoff at this level
	Max        time.Duration `yaml:"max_period"`  // Increase exponentially to this level
	MaxRetries int           `yaml:"max_retries"` // Give up after this many; zero means infinite retries
}

Config configures a Backoff.