// Open runs the invalidation loop.
func (rci *RowcacheInvalidator) Open(dbname string, mysqld *mysqlctl.Mysqld) {
rp, err := mysqld.MasterStatus()
if err != nil {
panic(NewTabletError(FATAL, "Rowcache invalidator aborting: cannot determine replication position: %v", err))
}
if mysqld.Cnf().BinLogPath == "" {
panic(NewTabletError(FATAL, "Rowcache invalidator aborting: binlog path not specified"))
}
ok := rci.svm.Go(func(_ *sync2.ServiceManager) {
rci.mu.Lock()
rci.dbname = dbname
rci.mysqld = mysqld
rci.evs = binlog.NewEventStreamer(dbname, mysqld.Cnf().BinLogPath)
rci.GroupId.Set(rp.MasterLogGroupId)
rci.mu.Unlock()
rci.run()
rci.mu.Lock()
rci.evs = nil
rci.mu.Unlock()
})
if ok {
log.Infof("Rowcache invalidator starting, dbname: %s, path: %s, logfile: %s, position: %d", dbname, mysqld.Cnf().BinLogPath, rp.MasterLogFile, rp.MasterLogPosition)
} else {
log.Infof("Rowcache invalidator already running")
}
}
func (rci *RowcacheInvalidator) run(ctx *sync2.ServiceContext) error {
for {
evs := binlog.NewEventStreamer(rci.dbname, rci.mysqld, rci.Position(), rci.processEvent)
// We wrap this code in a func so we can catch all panics.
// If an error is returned, we log it, wait 1 second, and retry.
// This loop can only be stopped by calling Close.
err := func() (inner error) {
defer func() {
if x := recover(); x != nil {
inner = fmt.Errorf("%v: uncaught panic:\n%s", x, tb.Stack(4))
}
}()
return evs.Stream(ctx)
}()
if err == nil || !ctx.IsRunning() {
break
}
if IsConnErr(err) {
rci.checker.CheckMySQL()
}
log.Errorf("binlog.ServeUpdateStream returned err '%v', retrying in 1 second.", err.Error())
rci.qe.queryServiceStats.InternalErrors.Add("Invalidation", 1)
time.Sleep(1 * time.Second)
}
log.Infof("Rowcache invalidator stopped")
return nil
}
// UpdateStream streams binlog events.
func (tsv *TabletServer) UpdateStream(ctx context.Context, target *querypb.Target, position string, timestamp int64, sendReply func(*querypb.StreamEvent) error) error {
// Parse the position if needed.
var p replication.Position
var err error
if timestamp == 0 {
p, err = replication.DecodePosition(position)
if err != nil {
return NewTabletError(vtrpcpb.ErrorCode_BAD_INPUT, "cannot parse position: %v", err)
}
} else if position != "" {
return NewTabletError(vtrpcpb.ErrorCode_BAD_INPUT, "only one of position and timestamp should be specified")
}
// Validate proper target is used.
if err = tsv.startRequest(target, false, false); err != nil {
return err
}
defer tsv.endRequest(false)
s := binlog.NewEventStreamer(tsv.dbconfigs.App.DbName, tsv.mysqld, p, timestamp, func(event *querypb.StreamEvent) error {
return sendReply(event)
})
// Create a cancelable wrapping context.
streamCtx, streamCancel := context.WithCancel(ctx)
i := tsv.updateStreamList.Add(streamCancel)
defer tsv.updateStreamList.Delete(i)
// And stream with it.
err = s.Stream(streamCtx)
switch err {
case mysqlctl.ErrBinlogUnavailable:
return NewTabletError(vtrpcpb.ErrorCode_QUERY_NOT_SERVED, "%v", err)
case nil:
return nil
default:
return NewTabletError(vtrpcpb.ErrorCode_INTERNAL_ERROR, "%v", err)
}
}