micron

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

type Job struct {
	// The unique name of the job.
	Name string

	// The cron expression. Three formats are supported currently:
	//
	// 1. Fixed-interval schedule:
	//
	//		@every <duration>
	//
	//	where `<duration>` is a string accepted by `time.ParseDuration` (http://golang.org/pkg/time/#ParseDuration).
	//
	// 2. Predefined cron expression (https://github.com/gorhill/cronexpr#predefined-cron-expressions):
	//
	//		@annually
	//		@yearly
	//		@monthly
	//		@weekly
	//		@daily
	//		@hourly
	//
	// 3. Standard cron expression (https://github.com/gorhill/cronexpr#implementation).
	//
	// Note that the execution interval of the job must be greater than LockTTL.
	Expr string

	// The old-style handler of the job.
	Task func()

	// The new-style handler of the job.
	//
	// Note that Handler will be preferred if both Task and Handler are specified.
	Handler func(context.Context) error
}

type Locker interface {
	// Lock obtains the lock to execute the job named job. If the lock is
	// successfully obtained, Lock will return true, otherwise it will return false.
	//
	// The implementation of Locker must release the obtained lock automatically
	// after ttl elapses.
	Lock(job string, ttl time.Duration) (bool, error)
}

type NilLocker struct{}

type Options struct {
	// The location name, which must be "Local", "UTC" or a location name corresponding
	// to a file in the IANA Time Zone database, such as "Asia/Shanghai".
	//
	// Defaults to "UTC".
	Timezone string

	// LockTTL is the time duration after which the successfully obtained lock
	// will be released. It is a time window used to protect a job from
	// being executed more than once per execution time of its schedule,
	// which may be caused by the clock error among different machines.
	//
	// Defaults to 1s.
	LockTTL time.Duration

	// The handler for errors.
	ErrHandler func(error)
}

type Schedule interface {
	Next(time.Time) time.Time
}

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