// Internal control command.
// Migrate moves one slot data to another server on the fly.
func (c *CtrlContext) Migrate(host string, slotId uint16) error {
call := c.cli.newCall(proto.CmdMigrate, nil)
if call.err != nil {
return call.err
}
var p ctrl.PkgMigrate
p.ClientReq = true
p.MasterAddr = host
p.SlotId = slotId
pkg, err := ctrl.Encode(call.cmd, c.dbId, call.seq, &p)
if err != nil {
c.cli.errCall(call, err)
return err
}
call.pkg = pkg
c.cli.sending <- call
r, err := (<-call.Done).Reply()
if err != nil {
return err
}
t := r.(*ctrl.PkgMigrate)
if t.ErrMsg != "" {
return errors.New(t.ErrMsg)
}
return nil
}
func (srv *Server) replyMigrate(req *Request, msg string) {
ps := ctrl.PkgMigrate{}
ps.ErrMsg = msg
pkg, err := ctrl.Encode(req.Cmd, req.DbId, req.Seq, &ps)
if err == nil {
srv.sendResp(false, req, pkg)
}
}
func (slv *slave) SendSlaveOfToMaster() error {
slv.mtx.Lock()
var mi = slv.mi
var cli = slv.cli
slv.mtx.Unlock()
if cli == nil {
return nil
}
var err error
var pkg []byte
if mi.Migration {
var p ctrl.PkgMigrate
p.ClientReq = false
p.MasterAddr = mi.MasterAddr
p.SlaveAddr = mi.SlaveAddr
p.SlotId = mi.SlotId
pkg, err = ctrl.Encode(proto.CmdMigrate, 0, 0, &p)
if err != nil {
return err
}
} else {
lastSeq, valid := slv.bin.GetMasterSeq()
if !valid {
slv.mc.SetStatus(ctrl.SlaveNeedClear)
// Any better solution?
log.Fatalf("Slave lastSeq %d is out of sync, please clear old data! "+
"(Restart may fix this issue)", lastSeq)
}
var p ctrl.PkgSlaveOf
p.ClientReq = false
p.MasterAddr = mi.MasterAddr
p.SlaveAddr = mi.SlaveAddr
p.LastSeq = lastSeq
log.Printf("Connect to master %s with lastSeq %d\n",
mi.MasterAddr, p.LastSeq)
pkg, err = ctrl.Encode(proto.CmdSlaveOf, 0, 0, &p)
if err != nil {
return err
}
}
cli.AddResp(pkg)
return slv.mc.SetStatus(ctrl.SlaveFullSync)
}
func (srv *Server) migrate(req *Request) {
var cliType uint32 = ClientTypeNormal
if req.Cli != nil {
cliType = req.Cli.ClientType()
}
var p ctrl.PkgMigrate
var err = ctrl.Decode(req.Pkg, nil, &p)
if err == nil && !p.ClientReq {
srv.newMigMaster(req, &p)
return
}
switch cliType {
case ClientTypeNormal:
if err != nil {
log.Printf("Failed to Decode pkg: %s\n", err)
srv.replyMigrate(req, fmt.Sprintf("decode failed(%s)", err))
return
}
if !req.Cli.IsAuth(proto.AdminDbId) {
log.Printf("Not authorized!\n")
srv.replyMigrate(req, "no priviledge")
return
}
if len(p.SlaveAddr) == 0 {
p.SlaveAddr = req.Cli.LocalAddr().String()
}
if sameAddress(p.MasterAddr, p.SlaveAddr, req) {
log.Printf("Master and slave addresses are the same!\n")
srv.replyMigrate(req, "master and slave addresses are the same")
return
}
err = srv.mc.SetMigration(p.MasterAddr, p.SlaveAddr, p.SlotId)
if err != nil {
log.Printf("Failed to update migration config: %s\n", err)
srv.replyMigrate(req,
fmt.Sprintf("update migration config failed(%s)", err))
return
}
srv.rwMtx.Lock()
slv := srv.slv
srv.slv = nil
srv.rwMtx.Unlock()
if len(p.MasterAddr) > 0 {
if slv != nil {
slv.Close()
}
if srv.tbl.HasSlotData(p.SlotId) {
err = srv.mc.SetStatus(ctrl.SlaveNeedClear)
if err != nil {
log.Printf("Failed to set migration status: %s\n", err)
srv.replyMigrate(req,
fmt.Sprintf("failed to set migration status(%s)", err))
return
}
} else {
srv.connectToMaster(srv.mc)
}
} else {
if slv != nil {
go slv.DelayClose()
}
srv.bin.AsMaster()
}
srv.replyMigrate(req, "") // Success
case ClientTypeSlave:
fallthrough
case ClientTypeMaster:
if err != nil {
log.Printf("Failed to Decode pkg: %s\n", err)
} else {
log.Println("Invalid client type %d for Migrate command, close now!",
cliType)
}
req.Cli.Close()
}
}