// FinalSave should be called immediately before exiting, and only before
// exiting, in order to flush tasks to disk. It waits a short timeout for state
// to settle if necessary. If unable to reach a steady-state and save within
// this short timeout, it returns an error
func FinalSave(saver statemanager.Saver, taskEngine engine.TaskEngine) error {
engineDisabled := make(chan error)
disableTimer := time.AfterFunc(engineDisableTimeout, func() {
engineDisabled <- errors.New("Timed out waiting for TaskEngine to settle")
})
go func() {
log.Debug("Shutting down task engine")
taskEngine.Disable()
disableTimer.Stop()
engineDisabled <- nil
}()
disableErr := <-engineDisabled
stateSaved := make(chan error)
saveTimer := time.AfterFunc(finalSaveTimeout, func() {
stateSaved <- errors.New("Timed out trying to save to disk")
})
go func() {
log.Debug("Saving state before shutting down")
stateSaved <- saver.ForceSave()
saveTimer.Stop()
}()
saveErr := <-stateSaved
if disableErr != nil || saveErr != nil {
return utils.NewMultiError(disableErr, saveErr)
}
return nil
}
// handlePayloadMessage attempts to add each task to the taskengine and, if it can, acks the request.
func handlePayloadMessage(responseChan chan<- string, cluster, containerInstanceArn string, payload *ecsacs.PayloadMessage, taskEngine engine.TaskEngine, client api.ECSClient, saver statemanager.Saver) {
if payload.MessageId == nil {
log.Crit("Recieved a payload with no message id", "payload", payload)
return
}
allTasksHandled := addPayloadTasks(client, cluster, containerInstanceArn, payload, taskEngine)
// save the state of tasks we know about after passing them to the task engine
err := saver.Save()
if err != nil {
log.Error("Error saving state for payload message!", "err", err, "messageId", *payload.MessageId)
// Don't ack; maybe we can save it in the future.
return
}
if allTasksHandled {
go func() {
// Throw the ack in async; it doesn't really matter all that much and this is blocking handling more tasks.
responseChan <- *payload.MessageId
}()
// Record the sequence number as well
if payload.SeqNum != nil {
SequenceNumber.Set(*payload.SeqNum)
}
}
}