scheduledtask

Documentation

Overview

Package scheduledtask implements a task scheduler.

Index

• type DALFunc
• type Job
• type Scheduler
  • func New(ctx context.Context, id model.ControllerKey) *Scheduler
  • func NewForTesting(ctx context.Context, id model.ControllerKey, clock clock.Clock) *Scheduler
  • func (s *Scheduler) Parallel(retry backoff.Backoff, job Job)
  • func (s *Scheduler) Singleton(retry backoff.Backoff, job Job)
  • func (s *Scheduler) UpdatedControllerList(ctx context.Context, controllers []dal.Controller)

Types

type DALFunc

type DALFunc func(ctx context.Context, all bool) ([]dal.Controller, error)

type Job

type Job func(ctx context.Context) (time.Duration, error)

A Job is a function that is scheduled to run periodically.

The Job itself controls its schedule by returning the next time it should run.

type Scheduler

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

Scheduler is a task scheduler for the controller.

Each job runs in its own goroutine.

The scheduler uses a consistent hash ring to attempt to ensure that jobs are only run on a single controller at a time. This is not guaranteed, however, as the hash ring is only updated periodically and controllers may have inconsistent views of the hash ring.

func New

func New(ctx context.Context, id model.ControllerKey) *Scheduler

New creates a new Scheduler.

func NewForTesting

func NewForTesting(ctx context.Context, id model.ControllerKey, clock clock.Clock) *Scheduler

func (*Scheduler) Parallel

func (s *Scheduler) Parallel(retry backoff.Backoff, job Job)

Parallel schedules a job to run on every controller.

func (*Scheduler) Singleton

func (s *Scheduler) Singleton(retry backoff.Backoff, job Job)

Singleton schedules a job to attempt to run on only a single controller.

This is not guaranteed, however, as controllers may have inconsistent views of the hash ring.

func (*Scheduler) UpdatedControllerList

func (s *Scheduler) UpdatedControllerList(ctx context.Context, controllers []dal.Controller)

UpdatedControllerList synchronises the hash ring with the active controllers.