69 lines
1.3 KiB
Go
69 lines
1.3 KiB
Go
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package subscriptions
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import (
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"errors"
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"fmt"
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"time"
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)
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type SubscriptionID string
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type Subscription struct {
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id SubscriptionID
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signal *filterSignal
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quit chan struct{}
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filter filter
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stopped bool
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}
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func NewSubscription(namespace string, filter filter) *Subscription {
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subscriptionID := NewSubscriptionID(namespace, filter.getID())
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quit := make(chan struct{})
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return &Subscription{
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id: subscriptionID,
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quit: quit,
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signal: newFilterSignal(string(subscriptionID)),
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filter: filter,
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}
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}
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func (s *Subscription) Start(checkPeriod time.Duration) error {
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if s.stopped {
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return errors.New("it is impossible to start an already stopped subscription")
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}
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ticker := time.NewTicker(checkPeriod)
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defer ticker.Stop()
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for {
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select {
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case <-ticker.C:
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filterData, err := s.filter.getChanges()
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if err != nil {
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s.signal.SendError(err)
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} else if len(filterData) > 0 {
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s.signal.SendData(filterData)
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}
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case <-s.quit:
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return nil
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}
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}
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}
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func (s *Subscription) Stop(uninstall bool) error {
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if s.stopped {
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return nil
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}
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close(s.quit)
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if uninstall {
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return s.filter.uninstall()
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}
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s.stopped = true
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return nil
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}
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func NewSubscriptionID(namespace, filterID string) SubscriptionID {
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return SubscriptionID(fmt.Sprintf("%s-%s", namespace, filterID))
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}
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