// Open try to build query rules from local file and push the rules to vttablet
func (fcr *FileCustomRule) Open(qsc tabletserver.Controller, rulePath string) error {
fcr.path = rulePath
if fcr.path == "" {
// Don't go further if path is empty
return nil
}
data, err := ioutil.ReadFile(fcr.path)
if err != nil {
log.Warningf("Error reading file %v: %v", fcr.path, err)
// Don't update any internal cache, just return error
return err
}
qrs := tabletserver.NewQueryRules()
err = qrs.UnmarshalJSON(data)
if err != nil {
log.Warningf("Error unmarshaling query rules %v", err)
return err
}
fcr.currentRuleSetTimestamp = time.Now().Unix()
fcr.currentRuleSet = qrs.Copy()
// Push query rules to vttablet
qsc.SetQueryRules(FileCustomRuleSource, qrs.Copy())
log.Infof("Custom rule loaded from file: %s", fcr.path)
return nil
}
// refreshData gets query rules from Zookeeper and refresh internal QueryRules cache
// this function will also call TabletServer.SetQueryRules to propagate rule changes to query service
func (zkcr *ZkCustomRule) refreshData(qsc tabletserver.Controller, nodeRemoval bool) error {
data, stat, err := zkcr.zconn.Get(zkcr.path)
zkcr.mu.Lock()
defer zkcr.mu.Unlock()
if err == nil {
qrs := tabletserver.NewQueryRules()
if !nodeRemoval {
err = qrs.UnmarshalJSON([]byte(data))
if err != nil {
log.Warningf("Error unmarshaling query rules %v, original data '%s'", err, data)
return nil
}
}
zkcr.currentRuleSetVersion = stat.Mzxid()
if !reflect.DeepEqual(zkcr.currentRuleSet, qrs) {
zkcr.currentRuleSet = qrs.Copy()
qsc.SetQueryRules(ZkCustomRuleSource, qrs.Copy())
log.Infof("Custom rule version %v fetched from Zookeeper and applied to vttablet", zkcr.currentRuleSetVersion)
}
return nil
}
log.Warningf("Error encountered when trying to get data and watch from Zk: %v", err)
return err
}