gateway

type Creator func(ctx context.Context, hc discovery.HealthCheck, serv srvtopo.Server, cell string, retryCount int) Gateway

type Gateway interface {
	// TODO(alainjobart) The QueryService part of this interface
	// will be removed soon, in favor of the TargetStats part (that
	// returns a QueryService)
	queryservice.QueryService

	// srvtopo.TargetStats allows this Gateway to resolve a Target
	// into a QueryService. It is used by the srvtopo.Resolver object.
	srvtopo.TargetStats

	// WaitForTablets asks the gateway to wait for the provided
	// tablets types to be available. It the context is canceled
	// before the end, it should return ctx.Err().
	// The error returned will have specific effects:
	// - nil: keep going with startup.
	// - context.DeadlineExceeded: log a warning that we didn't get
	//   all tablets, and keep going with startup.
	// - any other error: log.Fatalf out.
	WaitForTablets(ctx context.Context, tabletTypesToWait []topodatapb.TabletType) error

	// RegisterStats registers exported stats for the gateway
	RegisterStats()

	// CacheStatus returns a list of TabletCacheStatus per shard / tablet type.
	CacheStatus() TabletCacheStatusList
}

type TabletCacheStatus struct {
	Keyspace   string
	Shard      string
	TabletType topodatapb.TabletType
	Name       string
	Addr       string

	QueryCount uint64
	QueryError uint64
	QPS        float64
	AvgLatency float64 // in milliseconds
}

type TabletCacheStatusList []*TabletCacheStatus

type TabletStatusAggregator struct {
	Keyspace   string
	Shard      string
	TabletType topodatapb.TabletType
	Name       string // the alternative name of a tablet
	Addr       string // the host:port of a tablet

	QueryCount uint64
	QueryError uint64
	// contains filtered or unexported fields
}