Example #1
0
// DiscoverLoop periodically calls orc.discover() until process termination.
// The Tablet is read from the given agent each time before calling discover().
// Usually this will be launched as a background goroutine.
func (orc *orcClient) DiscoverLoop(agent *ActionAgent) {
	if *orcInterval == 0 {
		// 0 means never.
		return
	}
	log.Infof("Starting periodic Orchestrator self-registration: API URL = %v, interval = %v", *orcAddr, *orcInterval)

	// Randomly vary the interval by +/- 25% to reduce the potential for spikes.
	ticker := timer.NewRandTicker(*orcInterval, *orcInterval/4)

	// Remember whether we've most recently succeeded or failed.
	var lastErr error

	for {
		// Do the first attempt immediately.
		err := orc.Discover(agent.Tablet())

		// Only log if we're transitioning between success and failure states.
		if (err != nil) != (lastErr != nil) {
			if err != nil {
				log.Warningf("Orchestrator self-registration attempt failed: %v", err)
			} else {
				log.Infof("Orchestrator self-registration succeeded.")
			}
		}
		lastErr = err

		// Wait for the next tick.
		// The only way to stop the loop is to terminate the process.
		<-ticker.C
	}
}
Example #2
0
// NewShardConn creates a new ShardConn. It creates a Balancer using
// serv, cell, keyspace, tabletType and retryDelay. retryCount is the max
// number of retries before a ShardConn returns an error on an operation.
func NewShardConn(ctx context.Context, serv topo.SrvTopoServer, cell, keyspace, shard string, tabletType topodatapb.TabletType, retryDelay time.Duration, retryCount int, connTimeoutTotal, connTimeoutPerConn, connLife time.Duration, tabletConnectTimings *stats.MultiTimings) *ShardConn {
	getAddresses := func() (*topodatapb.EndPoints, error) {
		endpoints, _, err := serv.GetEndPoints(ctx, cell, keyspace, shard, tabletType)
		if err != nil {
			return nil, vterrors.NewVitessError(
				vtrpcpb.ErrorCode_INTERNAL_ERROR, err,
				"endpoints fetch error: %v", err,
			)
		}
		return endpoints, nil
	}
	blc := NewBalancer(getAddresses, retryDelay)
	var ticker *timer.RandTicker
	if tabletType != topodatapb.TabletType_MASTER {
		ticker = timer.NewRandTicker(connLife, connLife/2)
	}
	sdc := &ShardConn{
		keyspace:           keyspace,
		shard:              shard,
		tabletType:         tabletType,
		retryDelay:         retryDelay,
		retryCount:         retryCount,
		connTimeoutTotal:   connTimeoutTotal,
		connTimeoutPerConn: connTimeoutPerConn,
		connLife:           connLife,
		balancer:           blc,
		ticker:             ticker,
		consolidator:       sync2.NewConsolidator(),
		connectTimings:     tabletConnectTimings,
	}
	if ticker != nil {
		go func() {
			for range ticker.C {
				sdc.closeCurrent()
			}
		}()
	}
	return sdc
}