46 lines
1.4 KiB
Go
46 lines
1.4 KiB
Go
package throttling
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import "time"
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// Throttling notifications to prometheus and web clients
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// TO be used in a single-threaded manner.
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type Throttler[T any] struct {
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minDelaySeconds float64
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// ucntion to call to implement the notification.
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notifier func(t *T)
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lastReportedTime time.Time
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pendingValue *T
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}
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func NewThrottler[T any](notifier func(t *T), minDelaySeconds float64) Throttler[T] {
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throttler := Throttler[T]{
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minDelaySeconds: minDelaySeconds,
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notifier: notifier,
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lastReportedTime: time.Time{},
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pendingValue: nil,
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}
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return throttler
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}
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// Notify there is a new value. Performs notification if it was long enough ago
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// for the last notification to be sent. If not, it is stored as a pending event to
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// be sent later. New events that come in before a notification is sent override the
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// pending event.
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func (throttler *Throttler[T]) Notify(time time.Time, value *T) {
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if time.Sub(throttler.lastReportedTime).Seconds() >= throttler.minDelaySeconds {
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throttler.notifier(value)
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throttler.lastReportedTime = time
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throttler.pendingValue = nil
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return
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}
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throttler.pendingValue = value
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}
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// To be called periodically. It sends out any pending events if the time the last
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// notification was sent is long enough ago.
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func (throttler *Throttler[T]) Ping(time time.Time) {
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if throttler.pendingValue != nil {
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throttler.Notify(time, throttler.pendingValue)
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}
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}
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