tasks

Documentation

Index

• type ConstantDelaySchedule
  • func Every(duration time.Duration) ConstantDelaySchedule
  • func (schedule ConstantDelaySchedule) Next(t time.Time) time.Time
• type Cron
  • func New() *Cron
  • func (c *Cron) AddFunc(spec string, cmd func()) error
  • func (c *Cron) AddJob(spec string, cmd Job) error
  • func (c *Cron) Entries() []*Entry
  • func (c *Cron) Schedule(schedule Schedule, cmd Job)
  • func (c *Cron) Start()
  • func (c *Cron) Stop()
• type Entry
• type FuncJob
  • func (f FuncJob) Run()
• type Job
• type Schedule
  • func Parse(spec string) (_ Schedule, err error)
• type SpecSchedule
  • func (s *SpecSchedule) Next(t time.Time) time.Time

Types

type ConstantDelaySchedule

type ConstantDelaySchedule struct {
	Delay time.Duration
}

ConstantDelaySchedule represents a simple recurring duty cycle, e.g. "Every 5 minutes". It does not support jobs more frequent than once a second.

func Every

func Every(duration time.Duration) ConstantDelaySchedule

Every returns a crontab Schedule that activates once every duration. Delays of less than a second are not supported (will round up to 1 second). Any fields less than a Second are truncated.

func (ConstantDelaySchedule) Next

func (schedule ConstantDelaySchedule) Next(t time.Time) time.Time

Next returns the next time this should be run. This rounds so that the next activation time will be on the second.

type Cron

type Cron struct {
	ErrorLog *log.Logger
	// contains filtered or unexported fields
}

Cron keeps track of any number of entries, invoking the associated func as specified by the schedule. It may be started, stopped, and the entries may be inspected while running.

func New

func New() *Cron

New returns a new Cron job runner.

func (*Cron) AddFunc

func (c *Cron) AddFunc(spec string, cmd func()) error

AddFunc adds a func to the Cron to be run on the given schedule.

func (*Cron) AddJob

func (c *Cron) AddJob(spec string, cmd Job) error

AddJob adds a Job to the Cron to be run on the given schedule.

func (*Cron) Entries

func (c *Cron) Entries() []*Entry

Entries returns a snapshot of the cron entries.

func (*Cron) Schedule

func (c *Cron) Schedule(schedule Schedule, cmd Job)

Schedule adds a Job to the Cron to be run on the given schedule.

func (*Cron) Start

func (c *Cron) Start()

Start the cron scheduler in its own go-routine.

func (*Cron) Stop

func (c *Cron) Stop()

Stop stops the cron scheduler if it is running; otherwise it does nothing.

type Entry

type Entry struct {
	// The schedule on which this job should be run.
	Schedule Schedule

	// The next time the job will run. This is the zero time if Cron has not been
	// started or this entry's schedule is unsatisfiable
	Next time.Time

	// The last time this job was run. This is the zero time if the job has never
	// been run.
	Prev time.Time

	// The Job to run.
	Job Job
}

Entry consists of a schedule and the func to execute on that schedule.

type FuncJob

type FuncJob func()

A wrapper that turns a func() into a cron.Job

func (FuncJob) Run

func (f FuncJob) Run()

type Job

type Job interface {
	Run()
}

Job is an interface for submitted cron jobs.

type Schedule

type Schedule interface {
	// Return the next activation time, later than the given time.
	// Next is invoked initially, and then each time the job is run.
	Next(time.Time) time.Time
}

The Schedule describes a job's duty cycle.

func Parse

func Parse(spec string) (_ Schedule, err error)

Parse returns a new crontab schedule representing the given spec. It returns a descriptive error if the spec is not valid.

It accepts

• Full crontab specs, e.g. "* * * * * ?"
• Descriptors, e.g. "@midnight", "@every 1h30m"

type SpecSchedule

type SpecSchedule struct {
	Second, Minute, Hour, Dom, Month, Dow uint64
}

SpecSchedule specifies a duty cycle (to the second granularity), based on a traditional crontab specification. It is computed initially and stored as bit sets.

func (*SpecSchedule) Next

func (s *SpecSchedule) Next(t time.Time) time.Time

Next returns the next time this schedule is activated, greater than the given time. If no time can be found to satisfy the schedule, return the zero time.