// caughtUp checks if the follower has really caught up, and adds it to the
// broker's follower set.
func (f *Follower) caughtUp(broker *Broker) bool {
broker.lock.Lock()
defer broker.lock.Unlock()
//log.Info("Obtained lock for %v", f.hostport)
expected := broker.tails()
for topic, offset := range expected {
if offset != f.tails[topic] {
log.Debug("Not fully caught up yet for %s. %d -> %d", topic, f.tails[topic], offset)
return false
}
}
// check if follower already in set. if so, delete prev entry.
for follower, _ := range broker.followers {
if f.hostport == follower.hostport {
delete(broker.followers, follower)
}
}
// add to set of followers
broker.followers[f] = true
// create struct to communicate with register
var addFollow protocol.InsyncChange
addFollow.Type = protocol.ADD
addFollow.HostPort = f.hostport
// add in-sync follower
// check if disconnect from register. if so, exit.
if err := websocket.JSON.Send(broker.regConn, addFollow); nil != err {
log.Warn("Unable to update register: %s.", err.Error())
}
return true
}
// removeFollower disconnects follower from followers set.
func (b *Broker) removeFollower(follower *Follower) {
_, exists := b.followers[follower]
if !exists {
return
}
delete(b.followers, follower)
// create struct to communicate with register
var removeFollow protocol.InsyncChange
removeFollow.Type = protocol.REMOVE
removeFollow.HostPort = follower.hostport
// add in-sync follower
// check if disconnect from register. if so, exit.
websocket.JSON.Send(b.regConn, removeFollow)
// checkError(err) // FIXME: exiting is not the correct thing to do
follower.quit <- nil
log.Info("Removed follower %v from follower set.", follower.hostport)
}
