Example #1
0
// updateReplicationGraphForPromotedSlave makes sure the newly promoted slave
// is correctly represented in the replication graph
func (agent *ActionAgent) updateReplicationGraphForPromotedSlave(ctx context.Context, tablet *topo.TabletInfo) error {
	// Update tablet regardless - trend towards consistency.
	tablet.State = topo.STATE_READ_WRITE
	tablet.Type = topo.TYPE_MASTER
	tablet.Parent.Cell = ""
	tablet.Parent.Uid = topo.NO_TABLET
	tablet.Health = nil
	err := topo.UpdateTablet(ctx, agent.TopoServer, tablet)
	if err != nil {
		return err
	}
	// NOTE(msolomon) A serving graph update is required, but in
	// order for the shard to be consistent the old master must be
	// scrapped first. That is externally coordinated by the
	// wrangler reparent action.

	// Insert the new tablet location in the replication graph now that
	// we've updated the tablet.
	err = topo.UpdateTabletReplicationData(ctx, agent.TopoServer, tablet.Tablet)
	if err != nil && err != topo.ErrNodeExists {
		return err
	}

	return nil
}