backoff

Documentation

Overview

Copyright 2020 New Relic Corporation. All rights reserved. SPDX-License-Identifier: Apache-2.0 Package backoff provides an exponential-backoff implementation. https://github.com/jpillora/backoff inlined for customizations.

Copyright 2020 New Relic Corporation. All rights reserved. SPDX-License-Identifier: Apache-2.0

Index

• Constants
• func GetMaxBackoffByCause(cause backendhttp.ErrorCause) time.Duration
• type Backoff
  • func NewDefaultBackoff() *Backoff
  • func (b *Backoff) Attempt() float64
  • func (b *Backoff) Backoff(ctx context.Context, d time.Duration)
  • func (b *Backoff) Copy() *Backoff
  • func (b *Backoff) Duration() time.Duration
  • func (b *Backoff) DurationWithMax(max time.Duration) time.Duration
  • func (b *Backoff) ForAttempt(attempt float64) time.Duration
  • func (b *Backoff) ForAttemptWithMax(attempt float64, max time.Duration) time.Duration
  • func (b *Backoff) IncreaseAttempt()
  • func (b *Backoff) Reset()
• type RetryManager
  • func NewRetrier() *RetryManager
  • func NewRetrierWithBackoff(backoff *Backoff) *RetryManager
  • func (m *RetryManager) RetryAfter() time.Duration
  • func (m *RetryManager) SetNextRetryAfter(duration time.Duration)
  • func (m *RetryManager) SetNextRetryWithBackoff()

Constants

const (
	DefaultFactor = 2
	DefaultJitter = true
	DefaultMin    = 1 * time.Second
	DefaultMax    = 5 * time.Minute
)

Default values

Functions

func GetMaxBackoffByCause

func GetMaxBackoffByCause(cause backendhttp.ErrorCause) time.Duration

GetMaxBackoffByCause will return the maximum backoff value based on the error cause.

Types

type Backoff

type Backoff struct {

	//Factor is the multiplying factor for each increment step
	Factor float64
	//Jitter eases contention by randomizing backoff steps
	Jitter bool
	//Min and Max are the minimum and maximum values of the counter
	Min, Max time.Duration
	// GetBackoffTimer function to handle the backoff.
	GetBackoffTimer func(time.Duration) *time.Timer
	// contains filtered or unexported fields
}

Backoff is a time.Duration counter, starting at Min. After every call to the Duration method the current timing is multiplied by Factor, but it never exceeds Max.

Backoff is not generally concurrent-safe, but the ForAttempt method can be used concurrently.

func NewDefaultBackoff

func NewDefaultBackoff() *Backoff

NewDefaultBackoff default behaviour for Vortex.

func (*Backoff) Attempt

func (b *Backoff) Attempt() float64

Attempt returns the current attempt counter value.

func (*Backoff) Backoff

func (b *Backoff) Backoff(ctx context.Context, d time.Duration)

Backoff waits for the specified duration or a signal from the ctx channel, whichever happens first.

func (*Backoff) Copy

func (b *Backoff) Copy() *Backoff

Copy returns a backoff with equals constraints as the original

func (*Backoff) Duration

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

Duration returns the duration for the current attempt.

func (*Backoff) DurationWithMax

func (b *Backoff) DurationWithMax(max time.Duration) time.Duration

Duration returns the duration for the current attempt. The result will be limited to max value.

func (*Backoff) ForAttempt

func (b *Backoff) ForAttempt(attempt float64) time.Duration

ForAttempt calls forAttempt with configured max/min values.

func (*Backoff) ForAttemptWithMax

func (b *Backoff) ForAttemptWithMax(attempt float64, max time.Duration) time.Duration

ForAttemptWithMax calls forAttempt with configured a max value limit.

func (*Backoff) IncreaseAttempt

func (b *Backoff) IncreaseAttempt()

IncreaseAttempt increases attempt counter value.

func (*Backoff) Reset

func (b *Backoff) Reset()

Reset restarts the current attempt counter at zero.

type RetryManager

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

RetryManager retries using 2 different approaches: - fixed time using SetNextRetryAfter - exponential backoff using SetNextRetryWithBackoff

func NewRetrier

func NewRetrier() *RetryManager

NewRetrier creates a new retrier

func NewRetrierWithBackoff

func NewRetrierWithBackoff(backoff *Backoff) *RetryManager

NewRetrierWithBackoff creates a new retrier with a specific backoff

func (*RetryManager) RetryAfter

func (m *RetryManager) RetryAfter() time.Duration

RetryAfter returns time to wait until next retry

func (*RetryManager) SetNextRetryAfter

func (m *RetryManager) SetNextRetryAfter(duration time.Duration)

SetNextRetryAfter : sets a provided time to wait

func (*RetryManager) SetNextRetryWithBackoff

func (m *RetryManager) SetNextRetryWithBackoff()

SetNextRetryWithBackoff sets a backoff for next retry that when called 2nd time it'll be increase exponentially