// Change the type of tablet and recompute all necessary derived paths in the
// serving graph.
// force: Bypass the vtaction system and make the data change directly, and
// do not run the remote hooks.
//
// Note we don't update the master record in the Shard here, as we can't
// ChangeType from and out of master anyway.
func (wr *Wrangler) ChangeType(tabletAlias topo.TabletAlias, dbType topo.TabletType, force bool) error {
// Load tablet to find keyspace and shard assignment.
// Don't load after the ChangeType which might have unassigned
// the tablet.
ti, err := wr.ts.GetTablet(tabletAlias)
if err != nil {
return err
}
rebuildRequired := ti.Tablet.IsServingType()
if force {
// with --force, we do not run any hook
err = tm.ChangeType(wr.ts, tabletAlias, dbType, false)
} else {
// the remote action will run the hooks
var actionPath string
actionPath, err = wr.ai.ChangeType(tabletAlias, dbType)
// You don't have a choice - you must wait for
// completion before rebuilding.
if err == nil {
err = wr.ai.WaitForCompletion(actionPath, wr.actionTimeout())
}
}
if err != nil {
return err
}
// we rebuild if the tablet was serving, or if it is now
var keyspaceToRebuild string
var shardToRebuild string
var cellToRebuild string
if rebuildRequired {
keyspaceToRebuild = ti.Keyspace
shardToRebuild = ti.Shard
cellToRebuild = ti.Cell
} else {
// re-read the tablet, see if we become serving
ti, err := wr.ts.GetTablet(tabletAlias)
if err != nil {
return err
}
if ti.Tablet.IsServingType() {
rebuildRequired = true
keyspaceToRebuild = ti.Keyspace
shardToRebuild = ti.Shard
cellToRebuild = ti.Cell
}
}
if rebuildRequired {
if err := wr.RebuildShardGraph(keyspaceToRebuild, shardToRebuild, []string{cellToRebuild}); err != nil {
return err
}
}
return nil
}
// ChangeTypeNoRebuild changes a tablet's type, and returns whether
// there's a shard that should be rebuilt, along with its cell,
// keyspace, and shard. If force is true, it will bypass the vtaction
// system and make the data change directly, and not run the remote
// hooks.
//
// Note we don't update the master record in the Shard here, as we
// can't ChangeType from and out of master anyway.
func (wr *Wrangler) ChangeTypeNoRebuild(tabletAlias topo.TabletAlias, tabletType topo.TabletType, force bool) (rebuildRequired bool, cell, keyspace, shard string, err error) {
// Load tablet to find keyspace and shard assignment.
// Don't load after the ChangeType which might have unassigned
// the tablet.
ti, err := wr.ts.GetTablet(tabletAlias)
if err != nil {
return false, "", "", "", err
}
if force {
if err := tabletmanager.ChangeType(wr.ts, tabletAlias, tabletType, nil, false); err != nil {
return false, "", "", "", err
}
} else {
if wr.UseRPCs {
if err := wr.ai.RpcChangeType(ti, tabletType, wr.actionTimeout()); err != nil {
return false, "", "", "", err
}
} else {
// the remote action will run the hooks
actionPath, err := wr.ai.ChangeType(tabletAlias, tabletType)
if err != nil {
return false, "", "", "", err
}
// You don't have a choice - you must wait for
// completion before rebuilding.
if err := wr.ai.WaitForCompletion(actionPath, wr.actionTimeout()); err != nil {
return false, "", "", "", err
}
}
}
if !ti.Tablet.IsInServingGraph() {
// re-read the tablet, see if we become serving
ti, err = wr.ts.GetTablet(tabletAlias)
if err != nil {
return false, "", "", "", err
}
if !ti.Tablet.IsInServingGraph() {
return false, "", "", "", nil
}
}
return true, ti.Alias.Cell, ti.Keyspace, ti.Shard, nil
}
func (tm *TabletManager) ChangeType(context *rpcproto.Context, args *topo.TabletType, reply *rpc.UnusedResponse) error {
return tm.agent.RpcWrapLockAction(context.RemoteAddr, actionnode.TABLET_ACTION_CHANGE_TYPE, args, reply, func() error {
return tabletmanager.ChangeType(tm.agent.TopoServer, tm.agent.TabletAlias, *args, true /*runHooks*/)
})
}