/
command.go
777 lines (686 loc) · 20.8 KB
/
command.go
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// Copyright 2014 The go-mysql Authors. All rights reserved.
// Use of this source code is governed by a MIT License
// that can be found in the LICENSES/go-mysql-LICENSE file.
// Copyright 2018 The kingbus Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package mysql
import (
"context"
"hash/crc32"
"github.com/flike/kingbus/storage/storagepb"
"runtime"
"encoding/binary"
"time"
"strings"
"fmt"
"github.com/flike/kingbus/log"
"github.com/flike/kingbus/storage"
"github.com/flike/kingbus/utils"
"github.com/pingcap/parser"
"github.com/pingcap/parser/ast"
_ "github.com/pingcap/tidb/types/parser_driver" //need by parser
metrics "github.com/rcrowley/go-metrics"
gomysql "github.com/siddontang/go-mysql/mysql"
"github.com/siddontang/go-mysql/replication"
)
//MaxHeartbeatPeriod is ten years
var MaxHeartbeatPeriod = time.Hour * 24 * 30 * 12 * 10
const (
//ServerID is the variable name of server id in mysql
ServerID = "server_id"
//ServerUUID is the variable name of server uuid in mysql
ServerUUID = "server_uuid"
//SlaveUUID is the variable name of slave uuid in mysql
SlaveUUID = "slave_uuid"
//MasterHeartbeatPeriod is the variable name of master_heartbeat_period in mysql
MasterHeartbeatPeriod = "master_heartbeat_period"
//GtidMode is the variable name of gtid_mode in mysql
GtidMode = "gtid_mode"
//GtidPurged is the variable name of gtid_purged in mysql
GtidPurged = "gtid_purged"
//VersionComment is the variable name of version_comment in mysql
VersionComment = "version_comment"
//BinlogFormat is the variable name of binlog_format in mysql
BinlogFormat = "binlog_format"
//BinlogChecksum is the variable name of binlog_checksum in mysql
BinlogChecksum = "binlog_checksum"
//MasterBinlogChecksum is the variable name of master_binlog_checksum in mysql
MasterBinlogChecksum = "master_binlog_checksum"
//SetNames using in the replication interaction process
SetNames = "setnames"
//UnixTimestamp is the variable name of unix_timestamp in mysql
UnixTimestamp = "unix_timestamp"
//Version is the variable name of version in mysql
Version = "version"
)
func (c *Conn) dispatch(ctx context.Context, data []byte) error {
cmd := data[0]
data = data[1:]
switch cmd {
case gomysql.COM_QUIT:
c.Close()
log.Log.Debugf("close client connection")
return nil
case gomysql.COM_QUERY:
return c.handleQuery(utils.BytesToString(data))
case gomysql.COM_PING:
return c.writeOK(nil)
case gomysql.COM_BINLOG_DUMP_GTID:
return c.handleBinlogDumpGtid(ctx, data)
case gomysql.COM_REGISTER_SLAVE:
return c.handleRegisterSlave(data)
default:
log.Log.Errorf("master not support this cmd:%v", data)
return c.writeError(ErrSQLNotSupport)
}
return nil
}
func (c *Conn) handleQuery(sql string) (err error) {
defer func() {
if e := recover(); e != nil {
if myerr, ok := e.(error); ok {
const size = 4096
buf := make([]byte, size)
buf = buf[:runtime.Stack(buf, false)]
log.Log.Errorf("Conn handleQuery error,err:%s,sql:%s,stack:%s", myerr, sql, string(buf))
err = myerr
}
return
}
}()
log.Log.Infof("handleQuery sql:%s", sql)
sqlParser := parser.New()
stmt, err := sqlParser.ParseOneStmt(sql, "", "")
if err != nil {
return err
}
switch v := stmt.(type) {
case *ast.ShowStmt:
return c.handleShow(v)
case *ast.SelectStmt:
return c.handleSelect(v)
case *ast.SetStmt:
return c.handleSet(v)
case *ast.KillStmt:
return c.handleKill(v)
//todo get metrics of slave
default:
return ErrSQLNotSupport
}
return
}
//SELECT @@GLOBAL.SERVER_UUID
//SELECT @@GLOBAL.SERVER_ID
//SELECT @master_binlog_checksum
//SELECT UNIX_TIMESTAMP()
//SELECT @@gtid_mode
//SELECT @@gtid_purged
func (c *Conn) handleSelect(stmt *ast.SelectStmt) error {
if len(stmt.Fields.Fields) == 1 {
columnName := stmt.Fields.Fields[0].Text()
switch v := stmt.Fields.Fields[0].Expr.(type) {
case *ast.VariableExpr:
return c.handleSelectVariableExpr(v, columnName)
case *ast.FuncCallExpr:
return c.handleSelectFuncCallExpr(v, columnName)
}
}
return ErrSQLNotSupport
}
func (c *Conn) handleSelectVariableExpr(v *ast.VariableExpr, columnName string) error {
var result *gomysql.Resultset
var err error
switch strings.ToLower(v.Name) {
case ServerID, ServerUUID:
//SELECT @@GLOBAL.SERVER_UUID
//SELECT @@GLOBAL.SERVER_ID
masterInfo, err := c.binlogServer.GetMasterInfo()
if err != nil {
return err
}
if v.Name == ServerUUID {
result, err = gomysql.BuildSimpleResultset(
[]string{columnName},
[][]interface{}{
[]interface{}{masterInfo.ServerUUID},
},
false)
} else {
result, err = gomysql.BuildSimpleResultset(
[]string{columnName},
[][]interface{}{
[]interface{}{masterInfo.ServerID},
},
false)
}
case GtidMode:
result, err = gomysql.BuildSimpleResultset(
[]string{columnName},
[][]interface{}{
[]interface{}{"ON"},
},
false)
case GtidPurged:
gtidSet, err := c.binlogServer.GetGtidSet(gomysql.MySQLFlavor, storage.GtidPurgedKey)
if err != nil {
return err
}
result, err = gomysql.BuildSimpleResultset(
[]string{columnName},
[][]interface{}{
[]interface{}{gtidSet.String()},
},
false)
case VersionComment:
result, err = gomysql.BuildSimpleResultset(
[]string{columnName},
[][]interface{}{
[]interface{}{"MySQL Community Server (GPL)"},
},
false)
case BinlogFormat:
result, err = gomysql.BuildSimpleResultset(
[]string{columnName},
[][]interface{}{
[]interface{}{"ROW"},
},
false)
case BinlogChecksum:
result, err = gomysql.BuildSimpleResultset(
[]string{columnName},
[][]interface{}{
[]interface{}{"CRC32"},
},
false)
case MasterBinlogChecksum:
result, err = gomysql.BuildSimpleResultset(
[]string{columnName},
[][]interface{}{
[]interface{}{"CRC32"},
},
false)
}
if err != nil {
return err
}
err = c.writeResultset(result)
if err != nil {
return err
}
return nil
}
//SELECT UNIX_TIMESTAMP()
//SELECT VERSION()
func (c *Conn) handleSelectFuncCallExpr(v *ast.FuncCallExpr, columnName string) error {
var result *gomysql.Resultset
var err error
switch v.FnName.L {
case UnixTimestamp:
result, err = gomysql.BuildSimpleResultset(
[]string{columnName},
[][]interface{}{
[]interface{}{time.Now().Unix()},
},
false)
case Version:
masterInfo, err := c.binlogServer.GetMasterInfo()
if err != nil {
return err
}
result, err = gomysql.BuildSimpleResultset(
[]string{columnName},
[][]interface{}{
[]interface{}{masterInfo.Version},
},
false)
}
err = c.writeResultset(result)
if err != nil {
return err
}
return nil
}
func (c *Conn) handleShow(stmt *ast.ShowStmt) error {
showVariable := stmt.Pattern.Pattern.Text()
log.Log.Debugf("show query showVariable:%s", showVariable)
switch strings.ToLower(showVariable) {
case ServerID:
masterInfo, err := c.binlogServer.GetMasterInfo()
if err != nil {
return err
}
result, err := gomysql.BuildSimpleResultset(
[]string{showVariable},
[][]interface{}{
[]interface{}{masterInfo.ServerID},
},
false)
err = c.writeResultset(result)
if err != nil {
return err
}
}
return ErrSQLNotSupport
}
func (c *Conn) handleSet(stmt *ast.SetStmt) error {
if len(stmt.Variables) != 1 {
return ErrSQLNotSupport
}
name := strings.ToLower(stmt.Variables[0].Name)
switch name {
case MasterHeartbeatPeriod:
valueExpr := stmt.Variables[0].Value.(ast.ValueExpr)
//the period is an nano-secs
period := valueExpr.GetValue().(int64)
c.userVariables[MasterHeartbeatPeriod] = period
//set heartbeat in slave
if slaveUUID, ok := c.userVariables[SlaveUUID]; ok {
slaves := c.binlogServer.GetSlaves()
for _, s := range slaves {
if s.UUID == slaveUUID {
s.HeartBeat = time.Duration(period)
break
}
}
}
err := c.writeOK(nil)
if err != nil {
log.Log.Errorf("writeOK error,err:%s", err)
return err
}
return nil
case SlaveUUID:
valueExpr := stmt.Variables[0].Value.(ast.ValueExpr)
slaveUUID := valueExpr.GetString()
if len(slaveUUID) != 0 {
slaves := c.binlogServer.GetSlaves()
for _, s := range slaves {
if s.UUID == slaveUUID && s.Conn == c {
log.Log.Warningf("slave has been registered, slaveUUID:%s", slaveUUID)
}
}
}
c.userVariables[SlaveUUID] = slaveUUID
err := c.writeOK(nil)
if err != nil {
log.Log.Errorf("writeOK error,err:%s", err)
return err
}
return nil
case MasterBinlogChecksum:
// @@global.binlog_checksum or crc32
switch v := stmt.Variables[0].Value.(type) {
case *ast.VariableExpr:
if v.IsSystem == false || v.IsGlobal == false ||
strings.ToLower(v.Name) != "binlog_checksum" {
return ErrChecksum
}
case ast.ValueExpr:
if strings.ToLower(v.GetString()) != "crc32" {
return ErrChecksum
}
}
c.userVariables[MasterBinlogChecksum] = "crc32"
err := c.writeOK(nil)
if err != nil {
log.Log.Errorf("writeOK error,err:%s", err)
return err
}
return nil
case SetNames:
valueExpr := stmt.Variables[0].Value.(ast.ValueExpr)
c.userVariables[SetNames] = valueExpr.GetString()
err := c.writeOK(nil)
if err != nil {
log.Log.Errorf("writeOK error,err:%s", err)
return err
}
return nil
}
return ErrSQLNotSupport
}
//ignore this command, because kingbus will close connection automatically
func (c *Conn) handleKill(stmt *ast.KillStmt) error {
slaves := c.binlogServer.GetSlaves()
for _, s := range slaves {
if s.Conn.connectionID == uint32(stmt.ConnectionID) {
c.binlogServer.UnregisterSlave(s.UUID)
break
}
}
return c.writeOK(nil)
}
func (c *Conn) handleRegisterSlave(data []byte) error {
var s Slave
pos := 0
s.ServerID = int32(binary.LittleEndian.Uint32(data[pos:]))
pos += 4
hostNameLen := int(data[pos])
pos++
s.HostName = string(data[pos : pos+hostNameLen])
pos += hostNameLen
userLen := int(data[pos])
pos++
s.User = string(data[pos : pos+userLen])
pos += userLen
passwordLen := int(data[pos])
pos++
s.Password = string(data[pos : pos+passwordLen])
pos += passwordLen
s.Port = int16(binary.LittleEndian.Uint16(data[pos:]))
pos += 2
s.Rank = binary.LittleEndian.Uint32(data[pos:])
pos += 4
s.MasterID = binary.LittleEndian.Uint32(data[pos:])
s.State = REGISTERED
//kill the zombie dump thread with same uuid
c.killZombieDumpThreads()
if uuid, ok := c.userVariables[SlaveUUID]; ok {
s.UUID = uuid.(string)
} else {
s.UUID = ""
}
s.ConnectTime = time.Now()
s.Conn = c
err := c.binlogServer.RegisterSlave(&s)
if err != nil {
return err
}
log.Log.Infof("handleRegisterSlave:slave info:%v", s)
return c.writeOK(nil)
}
//todo kill the slave with same uuid
func (c *Conn) handleBinlogDumpGtid(ctx context.Context, data []byte) error {
var (
err error
heartbeatPeriod time.Duration
)
slaveGtidExecuted, slaveServerID, err := c.parseMysqlGtidDumpPacket(data)
if err != nil {
return err
}
//UnregisterSlave
slaveUUID := c.userVariables[SlaveUUID].(string)
defer c.binlogServer.UnregisterSlave(slaveUUID)
err = c.binlogServer.CheckGtidSet(gomysql.MySQLFlavor, slaveGtidExecuted)
if err != nil {
log.Log.Errorf("CheckGtidSet error,err:%s,slaveGtids:%v", err, slaveGtidExecuted)
return err
}
//get the previousGtidEvent raft index
preGtidEventIndex, err := c.binlogServer.GetMySQLDumpAt(slaveGtidExecuted)
if err != nil {
log.Log.Errorf("GetMySQLDumpAt error,err:%s,slaveGtids:%v", err, slaveGtidExecuted)
return err
}
fde, err := c.binlogServer.GetFde(preGtidEventIndex)
if err != nil {
log.Log.Errorf("handleBinlogDumpGtid:GetFde error,err:%s, gtidSet: %s,flavor:%s",
err, slaveGtidExecuted.String(), gomysql.MySQLFlavor)
return err
}
//1.send fake rotate event
masterServerID := binary.LittleEndian.Uint32(fde[5:])
fileName, err := c.binlogServer.GetNextBinlogFile(preGtidEventIndex)
if err != nil {
log.Log.Errorf("handleBinlogDumpGtid:GetNextBinlogFile error,err:%s, gtidSet: %s,flavor:%s",
err, slaveGtidExecuted.String(), gomysql.MySQLFlavor)
return err
}
err = c.sendFakeRotateEvent(masterServerID, fileName)
if err != nil {
log.Log.Errorf("handleBinlogDumpGtid:sendFakeRotateEvent error,err:%s, serverId: %d,fileName:%s",
err, masterServerID, fileName)
return err
}
//2.send fde
err = c.sendFormatDescriptionEvent(fde)
if err != nil {
log.Log.Errorf("handleBinlogDumpGtid:sendFormatDescriptionEvent error,err:%s, fde:%v",
err, fde)
return err
}
//3.send event
eventC := make(chan *storagepb.BinlogEvent, 2000)
errorC := make(chan error, 1)
err = c.binlogServer.DumpBinlogAt(ctx, preGtidEventIndex, slaveGtidExecuted, eventC, errorC)
if err != nil {
log.Log.Errorf("DumpBinlogAt error,err:%s,preGtidEventIndex:%d,slaveGtidExecuted:%v",
err, preGtidEventIndex, slaveGtidExecuted)
return err
}
//4.new metrics
slaveEps := metrics.NewMeter()
slaveThroughput := metrics.NewMeter()
metrics.Register(fmt.Sprintf("slave_eps_%d", slaveServerID), slaveEps)
metrics.Register(fmt.Sprintf("slave_thoughput_%d", slaveServerID), slaveThroughput)
if period, ok := c.userVariables[MasterHeartbeatPeriod]; ok {
heartbeatPeriod = time.Duration(period.(int64))
} else {
heartbeatPeriod = MaxHeartbeatPeriod
}
timer := time.NewTimer(heartbeatPeriod)
for {
select {
case event := <-eventC:
//event is not divided or the first divided event
//WriteEvent need write a ok_header(one byte),after the header size
if event.DividedCount == 0 || (0 < event.DividedCount && event.DividedSeqNum == 0) {
err = c.WriteEvent(event.Data, true)
if err != nil {
log.Log.Errorf("WriteEvent error,err:%s,event:%v", err, *event)
return err
}
} else {
err = c.WriteEvent(event.Data, false)
if err != nil {
log.Log.Errorf("WriteEvent error,err:%s,event:%v", err, *event)
return err
}
//event is divided,and the last packet size is MaxPayloadLen
//need send a empty packet
//https://dev.mysql.com/doc/internals/en/sending-more-than-16mbyte.html
if event.DividedSeqNum == event.DividedCount-1 && len(event.Data) == MaxPayloadLen {
err = c.WriteEvent(nil, false)
if err != nil {
log.Log.Errorf("WriteEvent error,err:%s,event:%v", err, *event)
return err
}
}
}
slaveEps.Mark(1)
slaveThroughput.Mark(int64(len(event.Data)))
//reset heartbeat period
resetTime(timer, heartbeatPeriod)
case err = <-errorC:
log.Log.Errorf("binlog server DumpBinlogAt error,err:%s", err)
return err
case <-ctx.Done():
log.Log.Errorf("handleBinlogDumpGtid:ctx done,quit")
return ctx.Err()
case <-timer.C:
//kingbus send the heartbeat log event which received by syncer to slave
log.Log.Debugf("send a heartbeat log event to slave")
err = c.sendHeartbeatEvent(masterServerID)
if err != nil {
return err
}
//reset heartbeat period
resetTime(timer, heartbeatPeriod)
}
}
return nil
}
func (c *Conn) killZombieDumpThreads() {
slaveUUID, ok := c.userVariables[SlaveUUID]
if !ok {
return
}
if len(slaveUUID.(string)) == 0 {
return
}
slaves := c.binlogServer.GetSlaves()
for uuid, slave := range slaves {
//different connection use the same uuid, kill the connection registered
if uuid == slaveUUID && slave.Conn != c {
log.Log.Debugf("killZombieDumpThreads:kill slave,uuid is:%s", slaveUUID)
c.binlogServer.UnregisterSlave(uuid)
return
}
}
}
func (c *Conn) parseMysqlGtidDumpPacket(data []byte) (*gomysql.MysqlGTIDSet, uint32, error) {
var flags uint16
var dataSize uint32
var slaveServerID uint32
var binlogFileNameSize uint32
var binlogFileName string
var binlogPos uint64
var pos uint32
flags = binary.LittleEndian.Uint16(data[pos:])
pos += 2
slaveServerID = binary.LittleEndian.Uint32(data[pos:])
pos += 4
binlogFileNameSize = binary.LittleEndian.Uint32(data[pos:])
pos += 4
binlogFileName = string(data[pos : pos+binlogFileNameSize])
pos += binlogFileNameSize
binlogPos = binary.LittleEndian.Uint64(data[pos:])
pos += 8
dataSize = binary.LittleEndian.Uint32(data[pos:])
pos += 4
//only support mysql gtid
slaveGtidExecuted, err := gomysql.DecodeMysqlGTIDSet(data[pos:])
if err != nil {
log.Log.Errorf("DecodeMysqlGTIDSet error,err:%s,data:%v", err, data[pos:])
return nil, 0, err
}
log.Log.Debugf("handleBinlogDumpGtid:flag:%d,slaveServerID:%d,binlogFileNameSize:%d,"+
"binlogFileName:%s,binlogPos:%d,dataSize:%d,slaveGtidExecuted:%v", flags, slaveServerID, binlogFileNameSize,
binlogFileName, binlogPos, dataSize, *slaveGtidExecuted)
return slaveGtidExecuted, slaveServerID, nil
}
//When starting to dump a binlog file, Format_description_log_event
//is read and sent first. If the requested position is after
//Format_description_log_event, log_pos field in the first
//Format_description_log_event has to be set to 0. So the slave
//will not increment its master's binlog position
func (c *Conn) sendFormatDescriptionEvent(data []byte) error {
//next_position
var LogPosOffset = 13
binary.LittleEndian.PutUint32(data[LogPosOffset:LogPosOffset+4], 0)
//remove crc32
data = data[:len(data)-4]
//recalculate the CRC
checksum := crc32.ChecksumIEEE(data)
computed := make([]byte, replication.BinlogChecksumLength)
binary.LittleEndian.PutUint32(computed, checksum)
data = append(data, computed...)
return c.WriteEvent(data, true)
}
func (c *Conn) sendHeartbeatEvent(serverID uint32) error {
binlogFile := c.binlogServer.LastBinlogFile()
filePosition := c.binlogServer.LastFilePosition()
data := buildHeartbeatEvent(binlogFile, serverID, filePosition)
return c.WriteEvent(data, true)
}
func buildHeartbeatEvent(fileName string, serverID uint32, logPos uint32) []byte {
eventHeader := &replication.EventHeader{
Timestamp: 0,
EventType: replication.HEARTBEAT_EVENT,
ServerID: serverID,
//enable crc32
EventSize: uint32(replication.EventHeaderSize + len(fileName) + replication.BinlogChecksumLength),
LogPos: logPos,
//LOG_ARTIFICIAL_F
Flags: 0x20,
}
eventBuf := encodeEventHeader(eventHeader)
fileNameBuf := utils.StringToBytes(fileName)
eventBuf = append(eventBuf, fileNameBuf...)
// mysql use zlib's CRC32 implementation, which uses polynomial 0xedb88320UL.
// reference: https://github.com/madler/zlib/blob/master/crc32.c
// https://github.com/madler/zlib/blob/master/doc/rfc1952.txt#L419
checksum := crc32.ChecksumIEEE(eventBuf)
computed := make([]byte, replication.BinlogChecksumLength)
binary.LittleEndian.PutUint32(computed, checksum)
eventBuf = append(eventBuf, computed...)
return eventBuf
}
//send a fake rotate event
//server_id comes from fde event
func (c *Conn) sendFakeRotateEvent(serverID uint32, fileName string) error {
var needCrc32 bool
if value, ok := c.userVariables[MasterBinlogChecksum]; ok {
if value == "crc32" {
needCrc32 = true
}
}
data := buildFakeRotateEvent(serverID, fileName, needCrc32)
return c.WriteEvent(data, true)
}
func buildFakeRotateEvent(serverID uint32, fileName string, needCrc32 bool) []byte {
eventHeader := &replication.EventHeader{
Timestamp: 0,
EventType: replication.ROTATE_EVENT,
ServerID: serverID,
//enable crc32
EventSize: uint32(replication.EventHeaderSize + 8 + len(fileName) + replication.BinlogChecksumLength),
LogPos: 0,
//LOG_ARTIFICIAL_F
Flags: 0x20,
}
eventBuf := encodeEventHeader(eventHeader)
//the requested pos from slave, usually 4
buf := make([]byte, 8)
binary.LittleEndian.PutUint64(buf[:], 4)
fileNameBuf := utils.StringToBytes(fileName)
eventBuf = append(eventBuf, buf...)
eventBuf = append(eventBuf, fileNameBuf...)
if needCrc32 {
// mysql use zlib's CRC32 implementation, which uses polynomial 0xedb88320UL.
// reference: https://github.com/madler/zlib/blob/master/crc32.c
// https://github.com/madler/zlib/blob/master/doc/rfc1952.txt#L419
checksum := crc32.ChecksumIEEE(eventBuf)
computed := make([]byte, replication.BinlogChecksumLength)
binary.LittleEndian.PutUint32(computed, checksum)
eventBuf = append(eventBuf, computed...)
}
return eventBuf
}
func encodeEventHeader(header *replication.EventHeader) []byte {
buf := make([]byte, replication.EventHeaderSize)
pos := 0
binary.LittleEndian.PutUint32(buf[pos:], header.Timestamp)
pos += 4
buf[pos] = byte(header.EventType)
pos++
binary.LittleEndian.PutUint32(buf[pos:], header.ServerID)
pos += 4
binary.LittleEndian.PutUint32(buf[pos:], header.EventSize)
pos += 4
binary.LittleEndian.PutUint32(buf[pos:], header.LogPos)
pos += 4
binary.LittleEndian.PutUint16(buf[pos:], header.Flags)
return buf
}
func resetTime(t *time.Timer, period time.Duration) {
if !t.Stop() {
select {
case <-t.C: //try to drain from the channel
default:
}
}
t.Reset(period)
}