func RunNewPuller(schedule RunSchedule, c *api.SyncGatewayClient, channel, name, feedType string, wg *sync.WaitGroup) {
defer wg.Done()
glExpvars.Add("user_active", 1)
var wakeupTime = time.Now()
var lastSeq interface{}
lastSeqFloat := c.GetLastSeq()
if lastSeqFloat < 0 {
Log("Puller, unable to establish last sequence number, exiting")
return
}
lastSeq = lastSeqFloat
if lastSeqFloat > MaxFirstFetch {
//FIX: This generates a sequence ID using internal knowledge of the gateway's sequence format.
lastSeq = lastSeqFloat - MaxFirstFetch // (for use with simple_sequences branch)
}
var changesFeed <-chan *api.Change
var changesResponse *http.Response
var cancelChangesFeed *bool
var pendingChanges []*api.Change
var fetchTimer <-chan time.Time
var checkpointSeqId int64 = 0
var checkpointTimer <-chan time.Time
online := false
scheduleIndex := 0
start := time.Now()
timer := time.NewTimer(schedule[scheduleIndex].start)
Log("Puller %s first transition at %v", name, schedule[scheduleIndex].start)
outer:
for {
select {
case <-timer.C:
// timer went off, transition modes
timeOffset := time.Since(start)
if online {
glExpvars.Add("user_awake", -1)
online = false
scheduleIndex++
if scheduleIndex < len(schedule) {
nextOnIn := schedule[scheduleIndex].start - timeOffset
timer = time.NewTimer(nextOnIn)
Log("Puller %s going offline, next on at %v", name, nextOnIn)
if nextOnIn < 0 {
log.Printf("WARNING: puller negative timer, exiting")
return
}
} else {
Log("Puller %s going offline, for good", name)
}
// transitioning off, cancel the changes feed, nil our changes feed channel
*cancelChangesFeed = false
if changesResponse != nil {
changesResponse.Body.Close()
}
changesFeed = nil
fetchTimer = nil
checkpointTimer = nil
pendingChanges = nil
} else {
glExpvars.Add("user_awake", 1)
online = true
if schedule[scheduleIndex].end != -1 {
nextOffIn := schedule[scheduleIndex].end - timeOffset
timer = time.NewTimer(nextOffIn)
Log("Puller %s going online, next off at %v", name, nextOffIn)
if nextOffIn < 0 {
log.Printf("WARNING: puller negative timer, exiting")
glExpvars.Add("user_awake", -1)
return
}
} else {
Log("Puller %s going online, for good", name)
}
// reset our wakeupTime to now
wakeupTime = time.Now()
Log("new wakeup time %v", wakeupTime)
// transitioning on, start a changes feed
changesFeed, cancelChangesFeed, changesResponse = c.GetChangesFeed(feedType, lastSeq)
Log("** Puller %s watching changes using %s feed...", name, feedType)
}
case change, ok := <-changesFeed:
// Received a change from the feed:
if !ok {
break outer
}
Log("Puller %s received %+v", name, *change)
pendingChanges = append(pendingChanges, change)
if fetchTimer == nil {
fetchTimer = time.NewTimer(FetchDelay).C
}
case <-fetchTimer:
// Time to get documents from the server:
fetchTimer = nil
var nDocs int
nDocs, lastSeq = pullChanges(c, pendingChanges, wakeupTime)
pendingChanges = nil
Log("Puller %s done reading %d docs", name, nDocs)
if nDocs > 0 && checkpointTimer == nil {
checkpointTimer = time.NewTimer(CheckpointInterval).C
}
case <-checkpointTimer:
// Time to save a checkpoint:
checkpointTimer = nil
checkpoint := api.Checkpoint{LastSequence: lastSeq}
checkpointHash := fmt.Sprintf("%s-%s", name, Hash(strconv.FormatInt(checkpointSeqId, 10)))
// save checkpoint asynchronously
go c.SaveCheckpoint(checkpointHash, checkpoint)
checkpointSeqId += 1
Log("Puller %s saved remote checkpoint", name)
}
}
}
