mirror of
https://github.com/HDT3213/godis.git
synced 2025-10-05 08:46:56 +08:00
replication master side
This commit is contained in:
finley
420
database/replication_slave.go
Normal file
420
database/replication_slave.go
Normal file
@@ -0,0 +1,420 @@
|
||||
package database
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"context"
|
||||
"errors"
|
||||
"fmt"
|
||||
"github.com/hdt3213/godis/config"
|
||||
"github.com/hdt3213/godis/interface/redis"
|
||||
"github.com/hdt3213/godis/lib/logger"
|
||||
"github.com/hdt3213/godis/lib/utils"
|
||||
"github.com/hdt3213/godis/redis/connection"
|
||||
"github.com/hdt3213/godis/redis/parser"
|
||||
"github.com/hdt3213/godis/redis/protocol"
|
||||
rdb "github.com/hdt3213/rdb/parser"
|
||||
"net"
|
||||
"strconv"
|
||||
"strings"
|
||||
"sync"
|
||||
"sync/atomic"
|
||||
"time"
|
||||
)
|
||||
|
||||
const (
|
||||
masterRole = iota
|
||||
slaveRole
|
||||
)
|
||||
|
||||
type slaveStatus struct {
|
||||
mutex sync.Mutex
|
||||
ctx context.Context
|
||||
cancel context.CancelFunc
|
||||
|
||||
// configVersion stands for the version of slaveStatus config. Any change of master host/port will cause configVersion increment
|
||||
// If configVersion change has been found during slaveStatus current slaveStatus procedure will stop.
|
||||
// It is designed to abort a running slaveStatus procedure
|
||||
configVersion int32
|
||||
|
||||
masterHost string
|
||||
masterPort int
|
||||
|
||||
masterConn net.Conn
|
||||
masterChan <-chan *parser.Payload
|
||||
replId string
|
||||
replOffset int64
|
||||
lastRecvTime time.Time
|
||||
running sync.WaitGroup
|
||||
}
|
||||
|
||||
var configChangedErr = errors.New("slaveStatus config changed")
|
||||
|
||||
func initReplSlaveStatus() *slaveStatus {
|
||||
return &slaveStatus{}
|
||||
}
|
||||
|
||||
func (mdb *MultiDB) execSlaveOf(c redis.Connection, args [][]byte) redis.Reply {
|
||||
if strings.ToLower(string(args[0])) == "no" &&
|
||||
strings.ToLower(string(args[1])) == "one" {
|
||||
mdb.slaveOfNone()
|
||||
return protocol.MakeOkReply()
|
||||
}
|
||||
host := string(args[0])
|
||||
port, err := strconv.Atoi(string(args[1]))
|
||||
if err != nil {
|
||||
return protocol.MakeErrReply("ERR value is not an integer or out of range")
|
||||
}
|
||||
mdb.slaveStatus.mutex.Lock()
|
||||
atomic.StoreInt32(&mdb.role, slaveRole)
|
||||
mdb.slaveStatus.masterHost = host
|
||||
mdb.slaveStatus.masterPort = port
|
||||
// use buffered channel in case receiver goroutine exited before controller send stop signal
|
||||
atomic.AddInt32(&mdb.slaveStatus.configVersion, 1)
|
||||
mdb.slaveStatus.mutex.Unlock()
|
||||
go mdb.setupMaster()
|
||||
return protocol.MakeOkReply()
|
||||
}
|
||||
|
||||
func (mdb *MultiDB) slaveOfNone() {
|
||||
mdb.slaveStatus.mutex.Lock()
|
||||
defer mdb.slaveStatus.mutex.Unlock()
|
||||
mdb.slaveStatus.masterHost = ""
|
||||
mdb.slaveStatus.masterPort = 0
|
||||
mdb.slaveStatus.replId = ""
|
||||
mdb.slaveStatus.replOffset = -1
|
||||
mdb.slaveStatus.stopSlaveWithMutex()
|
||||
}
|
||||
|
||||
// stopSlaveWithMutex stops in-progress connectWithMaster/fullSync/receiveAOF
|
||||
// invoker should have slaveStatus mutex
|
||||
func (repl *slaveStatus) stopSlaveWithMutex() {
|
||||
// update configVersion to stop connectWithMaster and fullSync
|
||||
atomic.AddInt32(&repl.configVersion, 1)
|
||||
// send cancel to receiveAOF
|
||||
if repl.cancel != nil {
|
||||
repl.cancel()
|
||||
repl.running.Wait()
|
||||
}
|
||||
repl.ctx = context.Background()
|
||||
repl.cancel = nil
|
||||
if repl.masterConn != nil {
|
||||
_ = repl.masterConn.Close() // parser.ParseStream will close masterChan
|
||||
}
|
||||
repl.masterConn = nil
|
||||
repl.masterChan = nil
|
||||
}
|
||||
|
||||
func (repl *slaveStatus) close() error {
|
||||
repl.mutex.Lock()
|
||||
defer repl.mutex.Unlock()
|
||||
repl.stopSlaveWithMutex()
|
||||
return nil
|
||||
}
|
||||
|
||||
func (mdb *MultiDB) setupMaster() {
|
||||
defer func() {
|
||||
if err := recover(); err != nil {
|
||||
logger.Error(err)
|
||||
}
|
||||
}()
|
||||
var configVersion int32
|
||||
ctx, cancel := context.WithCancel(context.Background())
|
||||
mdb.slaveStatus.mutex.Lock()
|
||||
mdb.slaveStatus.ctx = ctx
|
||||
mdb.slaveStatus.cancel = cancel
|
||||
configVersion = mdb.slaveStatus.configVersion
|
||||
mdb.slaveStatus.mutex.Unlock()
|
||||
isFullReSync, err := mdb.connectWithMaster(configVersion)
|
||||
if err != nil {
|
||||
// connect failed, abort master
|
||||
logger.Error(err)
|
||||
mdb.slaveOfNone()
|
||||
return
|
||||
}
|
||||
if isFullReSync {
|
||||
err = mdb.loadMasterRDB(configVersion)
|
||||
if err != nil {
|
||||
// load failed, abort master
|
||||
logger.Error(err)
|
||||
mdb.slaveOfNone()
|
||||
return
|
||||
}
|
||||
}
|
||||
err = mdb.receiveAOF(ctx, configVersion)
|
||||
if err != nil {
|
||||
// full sync failed, abort
|
||||
logger.Error(err)
|
||||
return
|
||||
}
|
||||
}
|
||||
|
||||
// connectWithMaster finishes handshake with master
|
||||
// returns: isFullReSync, error
|
||||
func (mdb *MultiDB) connectWithMaster(configVersion int32) (bool, error) {
|
||||
addr := mdb.slaveStatus.masterHost + ":" + strconv.Itoa(mdb.slaveStatus.masterPort)
|
||||
conn, err := net.Dial("tcp", addr)
|
||||
if err != nil {
|
||||
mdb.slaveOfNone() // abort
|
||||
return false, errors.New("connect master failed " + err.Error())
|
||||
}
|
||||
masterChan := parser.ParseStream(conn)
|
||||
|
||||
// ping
|
||||
pingCmdLine := utils.ToCmdLine("ping")
|
||||
pingReq := protocol.MakeMultiBulkReply(pingCmdLine)
|
||||
_, err = conn.Write(pingReq.ToBytes())
|
||||
if err != nil {
|
||||
return false, errors.New("send failed " + err.Error())
|
||||
}
|
||||
pingResp := <-masterChan
|
||||
if pingResp.Err != nil {
|
||||
return false, errors.New("read response failed: " + pingResp.Err.Error())
|
||||
}
|
||||
switch reply := pingResp.Data.(type) {
|
||||
case *protocol.StandardErrReply:
|
||||
if !strings.HasPrefix(reply.Error(), "NOAUTH") &&
|
||||
!strings.HasPrefix(reply.Error(), "NOPERM") &&
|
||||
!strings.HasPrefix(reply.Error(), "ERR operation not permitted") {
|
||||
logger.Error("Error reply to PING from master: " + string(reply.ToBytes()))
|
||||
mdb.slaveOfNone() // abort
|
||||
return false, nil
|
||||
}
|
||||
}
|
||||
|
||||
// just to reduce duplication of code
|
||||
sendCmdToMaster := func(conn net.Conn, cmdLine CmdLine, masterChan <-chan *parser.Payload) error {
|
||||
req := protocol.MakeMultiBulkReply(cmdLine)
|
||||
_, err := conn.Write(req.ToBytes())
|
||||
if err != nil {
|
||||
mdb.slaveOfNone() // abort
|
||||
return errors.New("send failed " + err.Error())
|
||||
}
|
||||
resp := <-masterChan
|
||||
if resp.Err != nil {
|
||||
mdb.slaveOfNone() // abort
|
||||
return errors.New("read response failed: " + resp.Err.Error())
|
||||
}
|
||||
if !protocol.IsOKReply(resp.Data) {
|
||||
mdb.slaveOfNone() // abort
|
||||
return errors.New("unexpected auth response: " + string(resp.Data.ToBytes()))
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// auth
|
||||
if config.Properties.MasterAuth != "" {
|
||||
authCmdLine := utils.ToCmdLine("auth", config.Properties.MasterAuth)
|
||||
err = sendCmdToMaster(conn, authCmdLine, masterChan)
|
||||
if err != nil {
|
||||
return false, err
|
||||
}
|
||||
}
|
||||
|
||||
// announce port
|
||||
var port int
|
||||
if config.Properties.SlaveAnnouncePort != 0 {
|
||||
port = config.Properties.SlaveAnnouncePort
|
||||
} else {
|
||||
port = config.Properties.Port
|
||||
}
|
||||
portCmdLine := utils.ToCmdLine("REPLCONF", "listening-port", strconv.Itoa(port))
|
||||
err = sendCmdToMaster(conn, portCmdLine, masterChan)
|
||||
if err != nil {
|
||||
return false, err
|
||||
}
|
||||
|
||||
// announce ip
|
||||
if config.Properties.SlaveAnnounceIP != "" {
|
||||
ipCmdLine := utils.ToCmdLine("REPLCONF", "ip-address", config.Properties.SlaveAnnounceIP)
|
||||
err = sendCmdToMaster(conn, ipCmdLine, masterChan)
|
||||
if err != nil {
|
||||
return false, err
|
||||
}
|
||||
}
|
||||
|
||||
// announce capacity
|
||||
capaCmdLine := utils.ToCmdLine("REPLCONF", "capa", "psync2")
|
||||
err = sendCmdToMaster(conn, capaCmdLine, masterChan)
|
||||
if err != nil {
|
||||
return false, err
|
||||
}
|
||||
|
||||
// update connection
|
||||
mdb.slaveStatus.mutex.Lock()
|
||||
defer mdb.slaveStatus.mutex.Unlock()
|
||||
if mdb.slaveStatus.configVersion != configVersion {
|
||||
// slaveStatus conf changed during connecting and waiting mutex
|
||||
return false, configChangedErr
|
||||
}
|
||||
mdb.slaveStatus.masterConn = conn
|
||||
mdb.slaveStatus.masterChan = masterChan
|
||||
mdb.slaveStatus.lastRecvTime = time.Now()
|
||||
return mdb.psyncHandshake()
|
||||
}
|
||||
|
||||
// psyncHandshake send `psync` to master and sync repl-id/offset with master
|
||||
// invoker should provide with slaveStatus.mutex
|
||||
func (mdb *MultiDB) psyncHandshake() (bool, error) {
|
||||
replId := "?"
|
||||
var replOffset int64 = -1
|
||||
if mdb.slaveStatus.replId != "" {
|
||||
replId = mdb.slaveStatus.replId
|
||||
replOffset = mdb.slaveStatus.replOffset
|
||||
}
|
||||
psyncCmdLine := utils.ToCmdLine("psync", replId, strconv.FormatInt(replOffset, 10))
|
||||
psyncReq := protocol.MakeMultiBulkReply(psyncCmdLine)
|
||||
_, err := mdb.slaveStatus.masterConn.Write(psyncReq.ToBytes())
|
||||
if err != nil {
|
||||
return false, errors.New("send failed " + err.Error())
|
||||
}
|
||||
psyncPayload := <-mdb.slaveStatus.masterChan
|
||||
if psyncPayload.Err != nil {
|
||||
return false, errors.New("read response failed: " + psyncPayload.Err.Error())
|
||||
}
|
||||
psyncHeader, ok := psyncPayload.Data.(*protocol.StatusReply)
|
||||
if !ok {
|
||||
return false, errors.New("illegal payload header not a status reply: " + string(psyncPayload.Data.ToBytes()))
|
||||
}
|
||||
headers := strings.Split(psyncHeader.Status, " ")
|
||||
if len(headers) != 3 && len(headers) != 2 {
|
||||
return false, errors.New("illegal payload header: " + psyncHeader.Status)
|
||||
}
|
||||
|
||||
logger.Info("receive psync header from master")
|
||||
var isFullReSync bool
|
||||
if headers[0] == "FULLRESYNC" {
|
||||
logger.Info("full re-sync with master")
|
||||
mdb.slaveStatus.replId = headers[1]
|
||||
mdb.slaveStatus.replOffset, err = strconv.ParseInt(headers[2], 10, 64)
|
||||
isFullReSync = true
|
||||
} else if headers[0] == "CONTINUE" {
|
||||
logger.Info("continue partial sync")
|
||||
mdb.slaveStatus.replId = headers[1]
|
||||
isFullReSync = false
|
||||
} else {
|
||||
return false, errors.New("illegal psync resp: " + psyncHeader.Status)
|
||||
}
|
||||
|
||||
if err != nil {
|
||||
return false, errors.New("get illegal repl offset: " + headers[2])
|
||||
}
|
||||
logger.Info(fmt.Sprintf("repl id: %s, current offset: %d", mdb.slaveStatus.replId, mdb.slaveStatus.replOffset))
|
||||
return isFullReSync, nil
|
||||
}
|
||||
|
||||
// loadMasterRDB downloads rdb after handshake has been done
|
||||
func (mdb *MultiDB) loadMasterRDB(configVersion int32) error {
|
||||
rdbPayload := <-mdb.slaveStatus.masterChan
|
||||
if rdbPayload.Err != nil {
|
||||
return errors.New("read response failed: " + rdbPayload.Err.Error())
|
||||
}
|
||||
rdbReply, ok := rdbPayload.Data.(*protocol.BulkReply)
|
||||
if !ok {
|
||||
return errors.New("illegal payload header: " + string(rdbPayload.Data.ToBytes()))
|
||||
}
|
||||
|
||||
logger.Info(fmt.Sprintf("receive %d bytes of rdb from master", len(rdbReply.Arg)))
|
||||
rdbDec := rdb.NewDecoder(bytes.NewReader(rdbReply.Arg))
|
||||
rdbHolder := MakeBasicMultiDB()
|
||||
err := importRDB(rdbDec, rdbHolder)
|
||||
if err != nil {
|
||||
return errors.New("dump rdb failed: " + err.Error())
|
||||
}
|
||||
|
||||
mdb.slaveStatus.mutex.Lock()
|
||||
defer mdb.slaveStatus.mutex.Unlock()
|
||||
if mdb.slaveStatus.configVersion != configVersion {
|
||||
// slaveStatus conf changed during connecting and waiting mutex
|
||||
return configChangedErr
|
||||
}
|
||||
for i, h := range rdbHolder.dbSet {
|
||||
newDB := h.Load().(*DB)
|
||||
mdb.loadDB(i, newDB)
|
||||
}
|
||||
|
||||
// fixme: update aof file
|
||||
return nil
|
||||
}
|
||||
|
||||
func (mdb *MultiDB) receiveAOF(ctx context.Context, configVersion int32) error {
|
||||
conn := connection.NewConn(mdb.slaveStatus.masterConn)
|
||||
conn.SetMaster()
|
||||
mdb.slaveStatus.running.Add(1)
|
||||
defer mdb.slaveStatus.running.Done()
|
||||
for {
|
||||
select {
|
||||
case payload, open := <-mdb.slaveStatus.masterChan:
|
||||
if !open {
|
||||
return errors.New("master channel unexpected close")
|
||||
}
|
||||
if payload.Err != nil {
|
||||
return payload.Err
|
||||
}
|
||||
cmdLine, ok := payload.Data.(*protocol.MultiBulkReply)
|
||||
if !ok {
|
||||
return errors.New("unexpected payload: " + string(payload.Data.ToBytes()))
|
||||
}
|
||||
mdb.slaveStatus.mutex.Lock()
|
||||
if mdb.slaveStatus.configVersion != configVersion {
|
||||
// slaveStatus conf changed during connecting and waiting mutex
|
||||
return configChangedErr
|
||||
}
|
||||
mdb.Exec(conn, cmdLine.Args)
|
||||
n := len(cmdLine.ToBytes()) // todo: directly get size from socket
|
||||
mdb.slaveStatus.replOffset += int64(n)
|
||||
mdb.slaveStatus.lastRecvTime = time.Now()
|
||||
logger.Info(fmt.Sprintf("receive %d bytes from master, current offset %d, %s",
|
||||
n, mdb.slaveStatus.replOffset, strconv.Quote(string(cmdLine.ToBytes()))))
|
||||
mdb.slaveStatus.mutex.Unlock()
|
||||
case <-ctx.Done():
|
||||
_ = conn.Close()
|
||||
return nil
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func (mdb *MultiDB) slaveCron() {
|
||||
repl := mdb.slaveStatus
|
||||
if repl.masterConn == nil {
|
||||
return
|
||||
}
|
||||
|
||||
// check master timeout
|
||||
replTimeout := 60 * time.Second
|
||||
if config.Properties.ReplTimeout != 0 {
|
||||
replTimeout = time.Duration(config.Properties.ReplTimeout) * time.Second
|
||||
}
|
||||
minLastRecvTime := time.Now().Add(-replTimeout)
|
||||
if repl.lastRecvTime.Before(minLastRecvTime) {
|
||||
// reconnect with master
|
||||
err := mdb.reconnectWithMaster()
|
||||
if err != nil {
|
||||
logger.Error("send failed " + err.Error())
|
||||
}
|
||||
return
|
||||
}
|
||||
// send ack to master
|
||||
err := repl.sendAck2Master()
|
||||
if err != nil {
|
||||
logger.Error("send failed " + err.Error())
|
||||
}
|
||||
}
|
||||
|
||||
// Send a REPLCONF ACK command to the master to inform it about the current processed offset
|
||||
func (repl *slaveStatus) sendAck2Master() error {
|
||||
psyncCmdLine := utils.ToCmdLine("REPLCONF", "ACK",
|
||||
strconv.FormatInt(repl.replOffset, 10))
|
||||
psyncReq := protocol.MakeMultiBulkReply(psyncCmdLine)
|
||||
_, err := repl.masterConn.Write(psyncReq.ToBytes())
|
||||
// logger.Info("send ack to master")
|
||||
return err
|
||||
}
|
||||
|
||||
func (mdb *MultiDB) reconnectWithMaster() error {
|
||||
logger.Info("reconnecting with master")
|
||||
mdb.slaveStatus.mutex.Lock()
|
||||
defer mdb.slaveStatus.mutex.Unlock()
|
||||
mdb.slaveStatus.stopSlaveWithMutex()
|
||||
go mdb.setupMaster()
|
||||
return nil
|
||||
}
|
||||
Reference in New Issue
Block a user