subscription.go

package servercomm

import (
	"sync"
	"time"
)

type Subscription struct {
	sync.Mutex
	id       int64
	C        chan PubSubMessage
	closed   bool
	closedCh chan bool
}

func CreateSubscription() *Subscription {
	return &Subscription{
		id:       time.Now().UnixNano(),
		C:        make(chan (PubSubMessage)),
		closedCh: make(chan bool),
	}
}

// ID returns the subscription ID.
func (sub *Subscription) ID() int64 {
	return sub.id
}

// Close closed the subscription and underlying channel. Operation is idempotent.
func (sub *Subscription) Close() {
	sub.Lock()
	defer sub.Unlock()

	if sub.closed {
		return
	}

	sub.closed = true
	close(sub.closedCh)
	close(sub.C)
}

// CloseNotify returns a channel that's passable when subscription in closed state.
func (sub *Subscription) CloseNotify() <-chan bool {
	return sub.closedCh
}