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tabletserver.go
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tabletserver.go
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/*
Copyright 2017 Google Inc.
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 tabletserver
import (
"bytes"
"fmt"
"io"
"net/http"
"os"
"os/signal"
"sort"
"strings"
"sync"
"syscall"
"time"
"golang.org/x/net/context"
"vitess.io/vitess/go/acl"
"vitess.io/vitess/go/hack"
"vitess.io/vitess/go/history"
"vitess.io/vitess/go/mysql"
"vitess.io/vitess/go/sqltypes"
"vitess.io/vitess/go/stats"
"vitess.io/vitess/go/sync2"
"vitess.io/vitess/go/tb"
"vitess.io/vitess/go/vt/binlog"
"vitess.io/vitess/go/vt/callerid"
"vitess.io/vitess/go/vt/dbconfigs"
"vitess.io/vitess/go/vt/dbconnpool"
"vitess.io/vitess/go/vt/log"
"vitess.io/vitess/go/vt/logutil"
"vitess.io/vitess/go/vt/sqlparser"
"vitess.io/vitess/go/vt/tableacl"
"vitess.io/vitess/go/vt/topo"
"vitess.io/vitess/go/vt/vterrors"
"vitess.io/vitess/go/vt/vttablet/heartbeat"
"vitess.io/vitess/go/vt/vttablet/queryservice"
"vitess.io/vitess/go/vt/vttablet/tabletserver/connpool"
"vitess.io/vitess/go/vt/vttablet/tabletserver/messager"
"vitess.io/vitess/go/vt/vttablet/tabletserver/planbuilder"
"vitess.io/vitess/go/vt/vttablet/tabletserver/rules"
"vitess.io/vitess/go/vt/vttablet/tabletserver/schema"
"vitess.io/vitess/go/vt/vttablet/tabletserver/splitquery"
"vitess.io/vitess/go/vt/vttablet/tabletserver/tabletenv"
"vitess.io/vitess/go/vt/vttablet/tabletserver/txserializer"
"vitess.io/vitess/go/vt/vttablet/tabletserver/txthrottler"
querypb "vitess.io/vitess/go/vt/proto/query"
topodatapb "vitess.io/vitess/go/vt/proto/topodata"
vtrpcpb "vitess.io/vitess/go/vt/proto/vtrpc"
)
const (
// StateNotConnected is the state where tabletserver is not
// connected to an underlying mysql instance.
StateNotConnected = iota
// StateNotServing is the state where tabletserver is connected
// to an underlying mysql instance, but is not serving queries.
StateNotServing
// StateServing is where queries are allowed.
StateServing
// StateTransitioning is a transient state indicating that
// the tabletserver is tranisitioning to a new state.
// In order to achieve clean transitions, no requests are
// allowed during this state.
StateTransitioning
// StateShuttingDown indicates that the tabletserver
// is shutting down. In this state, we wait for outstanding
// requests and transactions to conclude.
StateShuttingDown
)
// logPoolFull is for throttling transaction / query pool full messages in the log.
var logPoolFull = logutil.NewThrottledLogger("PoolFull", 1*time.Minute)
var logComputeRowSerializerKey = logutil.NewThrottledLogger("ComputeRowSerializerKey", 1*time.Minute)
// stateName names every state. The number of elements must
// match the number of states. Names can overlap.
var stateName = []string{
"NOT_SERVING",
"NOT_SERVING",
"SERVING",
"NOT_SERVING",
"SHUTTING_DOWN",
}
// stateDetail matches every state and optionally more information about the reason
// why the state is serving / not serving.
var stateDetail = []string{
"Not Connected",
"Not Serving",
"",
"Transitioning",
"Shutting Down",
}
// stateInfo returns a string representation of the state and optional detail
// about the reason for the state transition
func stateInfo(state int64) string {
if state == StateServing {
return "SERVING"
}
return fmt.Sprintf("%s (%s)", stateName[state], stateDetail[state])
}
// TabletServer implements the RPC interface for the query service.
// TabletServer is initialized in the following sequence:
// NewTabletServer->InitDBConfig->SetServingType.
// Subcomponents of TabletServer are initialized using one of the
// following sequences:
// New->InitDBConfig->Init->Open, or New->InitDBConfig->Open.
// Essentially, InitDBConfig is a continuation of New. However,
// the db config is not initially available. For this reason,
// the initialization is done in two phases.
// Some subcomponents have Init functions. Such functions usually
// perform one-time initializations like creating metadata tables
// in the sidecar database. These functions must be idempotent.
// Open and Close can be called repeatedly during the lifetime of
// a subcomponent. These should also be idempotent.
type TabletServer struct {
QueryTimeout sync2.AtomicDuration
BeginTimeout sync2.AtomicDuration
TerseErrors bool
enableHotRowProtection bool
// mu is used to access state. The lock should only be held
// for short periods. For longer periods, you have to transition
// the state to a transient value and release the lock.
// Once the operation is complete, you can then transition
// the state back to a stable value.
// The lameduck mode causes tablet server to respond as unhealthy
// for health checks. This does not affect how queries are served.
// target specifies the primary target type, and also allow specifies
// secondary types that should be additionally allowed.
mu sync.Mutex
state int64
lameduck sync2.AtomicInt32
target querypb.Target
alsoAllow []topodatapb.TabletType
requests sync.WaitGroup
beginRequests sync.WaitGroup
// The following variables should be initialized only once
// before starting the tabletserver.
dbconfigs *dbconfigs.DBConfigs
// The following variables should only be accessed within
// the context of a startRequest-endRequest.
se *schema.Engine
qe *QueryEngine
te *TxEngine
hw *heartbeat.Writer
hr *heartbeat.Reader
messager *messager.Engine
watcher *ReplicationWatcher
updateStreamList *binlog.StreamList
// checkMySQLThrottler is used to throttle the number of
// requests sent to CheckMySQL.
checkMySQLThrottler *sync2.Semaphore
// txThrottler is used to throttle transactions based on the observed replication lag.
txThrottler *txthrottler.TxThrottler
topoServer *topo.Server
// streamHealthMutex protects all the following fields
streamHealthMutex sync.Mutex
streamHealthIndex int
streamHealthMap map[int]chan<- *querypb.StreamHealthResponse
lastStreamHealthResponse *querypb.StreamHealthResponse
// history records changes in state for display on the status page.
// It has its own internal mutex.
history *history.History
// alias is used for identifying this tabletserver in healthcheck responses.
alias topodatapb.TabletAlias
}
// RegisterFunction is a callback type to be called when we
// Register() a TabletServer
type RegisterFunction func(Controller)
// RegisterFunctions is a list of all the
// RegisterFunction that will be called upon
// Register() on a TabletServer
var RegisterFunctions []RegisterFunction
// NewServer creates a new TabletServer based on the command line flags.
func NewServer(topoServer *topo.Server, alias topodatapb.TabletAlias) *TabletServer {
return NewTabletServer(tabletenv.Config, topoServer, alias)
}
var tsOnce sync.Once
// NewTabletServerWithNilTopoServer is typically used in tests that
// don't need a topoServer member.
func NewTabletServerWithNilTopoServer(config tabletenv.TabletConfig) *TabletServer {
return NewTabletServer(config, nil, topodatapb.TabletAlias{})
}
// NewTabletServer creates an instance of TabletServer. Only the first
// instance of TabletServer will expose its state variables.
func NewTabletServer(config tabletenv.TabletConfig, topoServer *topo.Server, alias topodatapb.TabletAlias) *TabletServer {
tsv := &TabletServer{
QueryTimeout: sync2.NewAtomicDuration(time.Duration(config.QueryTimeout * 1e9)),
BeginTimeout: sync2.NewAtomicDuration(time.Duration(config.TxPoolTimeout * 1e9)),
TerseErrors: config.TerseErrors,
enableHotRowProtection: config.EnableHotRowProtection || config.EnableHotRowProtectionDryRun,
checkMySQLThrottler: sync2.NewSemaphore(1, 0),
streamHealthMap: make(map[int]chan<- *querypb.StreamHealthResponse),
history: history.New(10),
topoServer: topoServer,
alias: alias,
}
tsv.se = schema.NewEngine(tsv, config)
tsv.qe = NewQueryEngine(tsv, tsv.se, config)
tsv.te = NewTxEngine(tsv, config)
tsv.hw = heartbeat.NewWriter(tsv, alias, config)
tsv.hr = heartbeat.NewReader(tsv, config)
tsv.txThrottler = txthrottler.CreateTxThrottlerFromTabletConfig(topoServer)
tsv.messager = messager.NewEngine(tsv, tsv.se, config)
tsv.watcher = NewReplicationWatcher(tsv.se, config)
tsv.updateStreamList = &binlog.StreamList{}
// FIXME(alainjobart) could we move this to the Register method below?
// So that vtcombo doesn't even call it once, on the first tablet.
// And we can remove the tsOnce variable.
tsOnce.Do(func() {
stats.NewGaugeFunc("TabletState", "Tablet server state", func() int64 {
tsv.mu.Lock()
state := tsv.state
tsv.mu.Unlock()
return state
})
stats.Publish("TabletStateName", stats.StringFunc(tsv.GetState))
// TabletServerState exports the same information as the above two stats (TabletState / TabletStateName),
// but exported with TabletStateName as a label for Prometheus, which doesn't support exporting strings as stat values.
stats.NewGaugesFuncWithMultiLabels("TabletServerState", "Tablet server state labeled by state name", []string{"name"}, func() map[string]int64 {
return map[string]int64{tsv.GetState(): 1}
})
stats.NewGaugeDurationFunc("QueryTimeout", "Tablet server query timeout", tsv.QueryTimeout.Get)
stats.NewGaugeDurationFunc("QueryPoolTimeout", "Tablet server timeout to get a connection from the query pool", tsv.qe.connTimeout.Get)
stats.NewGaugeDurationFunc("BeginTimeout", "Tablet server begin timeout", tsv.BeginTimeout.Get)
})
return tsv
}
// Register prepares TabletServer for serving by calling
// all the registrations functions.
func (tsv *TabletServer) Register() {
for _, f := range RegisterFunctions {
f(tsv)
}
tsv.registerDebugHealthHandler()
tsv.registerQueryzHandler()
tsv.registerStreamQueryzHandlers()
tsv.registerTwopczHandler()
}
// RegisterQueryRuleSource registers ruleSource for setting query rules.
func (tsv *TabletServer) RegisterQueryRuleSource(ruleSource string) {
tsv.qe.queryRuleSources.RegisterSource(ruleSource)
}
// UnRegisterQueryRuleSource unregisters ruleSource from query rules.
func (tsv *TabletServer) UnRegisterQueryRuleSource(ruleSource string) {
tsv.qe.queryRuleSources.UnRegisterSource(ruleSource)
}
// SetQueryRules sets the query rules for a registered ruleSource.
func (tsv *TabletServer) SetQueryRules(ruleSource string, qrs *rules.Rules) error {
err := tsv.qe.queryRuleSources.SetRules(ruleSource, qrs)
if err != nil {
return err
}
tsv.qe.ClearQueryPlanCache()
return nil
}
// GetState returns the name of the current TabletServer state.
func (tsv *TabletServer) GetState() string {
if tsv.lameduck.Get() != 0 {
return "NOT_SERVING"
}
tsv.mu.Lock()
name := stateName[tsv.state]
tsv.mu.Unlock()
return name
}
// setState changes the state and logs the event.
// It requires the caller to hold a lock on mu.
func (tsv *TabletServer) setState(state int64) {
log.Infof("TabletServer state: %s -> %s", stateInfo(tsv.state), stateInfo(state))
tsv.state = state
tsv.history.Add(&historyRecord{
Time: time.Now(),
ServingState: stateInfo(state),
TabletType: tsv.target.TabletType.String(),
})
}
// transition obtains a lock and changes the state.
func (tsv *TabletServer) transition(newState int64) {
tsv.mu.Lock()
tsv.setState(newState)
tsv.mu.Unlock()
}
// IsServing returns true if TabletServer is in SERVING state.
func (tsv *TabletServer) IsServing() bool {
return tsv.GetState() == "SERVING"
}
// InitDBConfig initializes the db config variables for TabletServer. You must call this function before
// calling SetServingType.
func (tsv *TabletServer) InitDBConfig(target querypb.Target, dbcfgs *dbconfigs.DBConfigs) error {
tsv.mu.Lock()
defer tsv.mu.Unlock()
if tsv.state != StateNotConnected {
return vterrors.Errorf(vtrpcpb.Code_UNKNOWN, "InitDBConfig failed, current state: %s", stateName[tsv.state])
}
tsv.target = target
tsv.dbconfigs = dbcfgs
tsv.se.InitDBConfig(tsv.dbconfigs)
tsv.qe.InitDBConfig(tsv.dbconfigs)
tsv.te.InitDBConfig(tsv.dbconfigs)
tsv.hw.InitDBConfig(tsv.dbconfigs)
tsv.hr.InitDBConfig(tsv.dbconfigs)
tsv.messager.InitDBConfig(tsv.dbconfigs)
tsv.watcher.InitDBConfig(tsv.dbconfigs)
return nil
}
func (tsv *TabletServer) initACL(tableACLConfigFile string, enforceTableACLConfig bool) {
// tabletacl.Init loads ACL from file if *tableACLConfig is not empty
err := tableacl.Init(
tableACLConfigFile,
func() {
tsv.ClearQueryPlanCache()
},
)
if err != nil {
log.Errorf("Fail to initialize Table ACL: %v", err)
if enforceTableACLConfig {
log.Exit("Need a valid initial Table ACL when enforce-tableacl-config is set, exiting.")
}
}
}
// InitACL loads the table ACL and sets up a SIGHUP handler for reloading it.
func (tsv *TabletServer) InitACL(tableACLConfigFile string, enforceTableACLConfig bool) {
tsv.initACL(tableACLConfigFile, enforceTableACLConfig)
sigChan := make(chan os.Signal, 1)
signal.Notify(sigChan, syscall.SIGHUP)
go func() {
for {
<-sigChan
tsv.initACL(tableACLConfigFile, enforceTableACLConfig)
}
}()
}
// StartService is a convenience function for InitDBConfig->SetServingType
// with serving=true.
func (tsv *TabletServer) StartService(target querypb.Target, dbcfgs *dbconfigs.DBConfigs) (err error) {
// Save tablet type away to prevent data races
tabletType := target.TabletType
err = tsv.InitDBConfig(target, dbcfgs)
if err != nil {
return err
}
_ /* state changed */, err = tsv.SetServingType(tabletType, true, nil)
return err
}
// EnterLameduck causes tabletserver to enter the lameduck state. This
// state causes health checks to fail, but the behavior of tabletserver
// otherwise remains the same. Any subsequent calls to SetServingType will
// cause the tabletserver to exit this mode.
func (tsv *TabletServer) EnterLameduck() {
tsv.lameduck.Set(1)
}
// ExitLameduck causes the tabletserver to exit the lameduck mode.
func (tsv *TabletServer) ExitLameduck() {
tsv.lameduck.Set(0)
}
const (
actionNone = iota
actionFullStart
actionServeNewType
actionGracefulStop
)
// SetServingType changes the serving type of the tabletserver. It starts or
// stops internal services as deemed necessary. The tabletType determines the
// primary serving type, while alsoAllow specifies other tablet types that
// should also be honored for serving.
// Returns true if the state of QueryService or the tablet type changed.
func (tsv *TabletServer) SetServingType(tabletType topodatapb.TabletType, serving bool, alsoAllow []topodatapb.TabletType) (stateChanged bool, err error) {
defer tsv.ExitLameduck()
action, err := tsv.decideAction(tabletType, serving, alsoAllow)
if err != nil {
return false, err
}
switch action {
case actionNone:
return false, nil
case actionFullStart:
if err := tsv.fullStart(); err != nil {
tsv.closeAll()
return true, err
}
return true, nil
case actionServeNewType:
if err := tsv.serveNewType(); err != nil {
tsv.closeAll()
return true, err
}
return true, nil
case actionGracefulStop:
tsv.gracefulStop()
return true, nil
}
panic("unreachable")
}
func (tsv *TabletServer) decideAction(tabletType topodatapb.TabletType, serving bool, alsoAllow []topodatapb.TabletType) (action int, err error) {
tsv.mu.Lock()
defer tsv.mu.Unlock()
tsv.alsoAllow = alsoAllow
// Handle the case where the requested TabletType and serving state
// match our current state. This avoids an unnecessary transition.
// There's no similar shortcut if serving is false, because there
// are different 'not serving' states that require different actions.
if tsv.target.TabletType == tabletType {
if serving && tsv.state == StateServing {
// We're already in the desired state.
return actionNone, nil
}
}
tsv.target.TabletType = tabletType
switch tsv.state {
case StateNotConnected:
if serving {
tsv.setState(StateTransitioning)
return actionFullStart, nil
}
case StateNotServing:
if serving {
tsv.setState(StateTransitioning)
return actionServeNewType, nil
}
case StateServing:
if !serving {
tsv.setState(StateShuttingDown)
return actionGracefulStop, nil
}
tsv.setState(StateTransitioning)
return actionServeNewType, nil
case StateTransitioning, StateShuttingDown:
return actionNone, vterrors.Errorf(vtrpcpb.Code_FAILED_PRECONDITION, "cannot SetServingType, current state: %s", stateName[tsv.state])
default:
panic("unreachable")
}
return actionNone, nil
}
func (tsv *TabletServer) fullStart() (err error) {
c, err := dbconnpool.NewDBConnection(tsv.dbconfigs.AppWithDB(), tabletenv.MySQLStats)
if err != nil {
log.Errorf("error creating db app connection: %v", err)
return err
}
c.Close()
if err := tsv.se.Open(); err != nil {
return err
}
if err := tsv.qe.Open(); err != nil {
return err
}
if err := tsv.te.Init(); err != nil {
return err
}
if err := tsv.hw.Init(tsv.target); err != nil {
return err
}
tsv.hr.Init(tsv.target)
tsv.updateStreamList.Init()
return tsv.serveNewType()
}
func (tsv *TabletServer) serveNewType() (err error) {
if tsv.target.TabletType == topodatapb.TabletType_MASTER {
if err := tsv.txThrottler.Open(tsv.target.Keyspace, tsv.target.Shard); err != nil {
return err
}
tsv.watcher.Close()
tsv.te.Open()
tsv.messager.Open()
tsv.hr.Close()
tsv.hw.Open()
} else {
tsv.messager.Close()
tsv.hr.Open()
tsv.hw.Close()
// Wait for in-flight transactional requests to complete
// before rolling back everything. In this state new
// transactional requests are not allowed. So, we can
// be sure that the tx pool won't change after the wait.
tsv.beginRequests.Wait()
tsv.te.Close(true)
tsv.watcher.Open()
tsv.txThrottler.Close()
// Reset the sequences.
tsv.se.MakeNonMaster()
}
tsv.transition(StateServing)
return nil
}
func (tsv *TabletServer) gracefulStop() {
defer close(tsv.setTimeBomb())
tsv.waitForShutdown()
tsv.transition(StateNotServing)
}
// StopService shuts down the tabletserver to the uninitialized state.
// It first transitions to StateShuttingDown, then waits for active
// services to shut down. Then it shuts down QueryEngine. This function
// should be called before process termination, or if MySQL is unreachable.
// Under normal circumstances, SetServingType should be called, which will
// keep QueryEngine open.
func (tsv *TabletServer) StopService() {
defer close(tsv.setTimeBomb())
defer tabletenv.LogError()
tsv.mu.Lock()
if tsv.state != StateServing && tsv.state != StateNotServing {
tsv.mu.Unlock()
return
}
tsv.setState(StateShuttingDown)
tsv.mu.Unlock()
log.Infof("Executing complete shutdown.")
tsv.waitForShutdown()
tsv.qe.Close()
tsv.se.Close()
tsv.hw.Close()
tsv.hr.Close()
log.Infof("Shutdown complete.")
tsv.transition(StateNotConnected)
}
func (tsv *TabletServer) waitForShutdown() {
// Wait till beginRequests have completed before waiting on tx pool.
// During this state, new Begins are not allowed. After the wait,
// we have the assurance that only non-begin transactional calls
// will be allowed. They will enable the conclusion of outstanding
// transactions.
tsv.beginRequests.Wait()
tsv.messager.Close()
tsv.te.Close(false)
tsv.qe.streamQList.TerminateAll()
tsv.updateStreamList.Stop()
tsv.watcher.Close()
tsv.requests.Wait()
tsv.txThrottler.Close()
}
// closeAll is called if TabletServer fails to start.
// It forcibly shuts down everything.
func (tsv *TabletServer) closeAll() {
tsv.messager.Close()
tsv.hr.Close()
tsv.hw.Close()
tsv.te.Close(true)
tsv.watcher.Close()
tsv.updateStreamList.Stop()
tsv.qe.Close()
tsv.se.Close()
tsv.txThrottler.Close()
tsv.transition(StateNotConnected)
}
func (tsv *TabletServer) setTimeBomb() chan struct{} {
done := make(chan struct{})
go func() {
qt := tsv.QueryTimeout.Get()
if qt == 0 {
return
}
tmr := time.NewTimer(10 * qt)
defer tmr.Stop()
select {
case <-tmr.C:
log.Fatal("Shutdown took too long. Crashing")
case <-done:
}
}()
return done
}
// IsHealthy returns nil for non-serving types or if the query service is healthy (able to
// connect to the database and serving traffic), or an error explaining
// the unhealthiness otherwise.
func (tsv *TabletServer) IsHealthy() error {
tsv.mu.Lock()
tabletType := tsv.target.TabletType
tsv.mu.Unlock()
switch tabletType {
case topodatapb.TabletType_MASTER, topodatapb.TabletType_REPLICA, topodatapb.TabletType_BATCH, topodatapb.TabletType_EXPERIMENTAL:
_, err := tsv.Execute(
tabletenv.LocalContext(),
nil,
"/* health */ select 1 from dual",
nil,
0,
nil,
)
return err
default:
return nil
}
}
// CheckMySQL initiates a check to see if MySQL is reachable.
// If not, it shuts down the query service. The check is rate-limited
// to no more than once per second.
func (tsv *TabletServer) CheckMySQL() {
if !tsv.checkMySQLThrottler.TryAcquire() {
return
}
go func() {
defer func() {
tabletenv.LogError()
time.Sleep(1 * time.Second)
tsv.checkMySQLThrottler.Release()
}()
if tsv.isMySQLReachable() {
return
}
log.Info("Check MySQL failed. Shutting down query service")
tsv.StopService()
}()
}
// isMySQLReachable returns true if we can connect to MySQL.
// The function returns false only if the query service is
// in StateServing or StateNotServing.
func (tsv *TabletServer) isMySQLReachable() bool {
tsv.mu.Lock()
switch tsv.state {
case StateServing:
// Prevent transition out of this state by
// reserving a request.
tsv.requests.Add(1)
defer tsv.requests.Done()
case StateNotServing:
// Prevent transition out of this state by
// temporarily switching to StateTransitioning.
tsv.setState(StateTransitioning)
defer func() {
tsv.transition(StateNotServing)
}()
default:
tsv.mu.Unlock()
return true
}
tsv.mu.Unlock()
return tsv.qe.IsMySQLReachable()
}
// ReloadSchema reloads the schema.
func (tsv *TabletServer) ReloadSchema(ctx context.Context) error {
return tsv.se.Reload(ctx)
}
// ClearQueryPlanCache clears internal query plan cache
func (tsv *TabletServer) ClearQueryPlanCache() {
// We should ideally bracket this with start & endErequest,
// but query plan cache clearing is safe to call even if the
// tabletserver is down.
tsv.qe.ClearQueryPlanCache()
}
// QueryService returns the QueryService part of TabletServer.
func (tsv *TabletServer) QueryService() queryservice.QueryService {
return tsv
}
// SchemaEngine returns the SchemaEngine part of TabletServer.
func (tsv *TabletServer) SchemaEngine() *schema.Engine {
return tsv.se
}
// Begin starts a new transaction. This is allowed only if the state is StateServing.
func (tsv *TabletServer) Begin(ctx context.Context, target *querypb.Target, options *querypb.ExecuteOptions) (transactionID int64, err error) {
err = tsv.execRequest(
ctx, tsv.BeginTimeout.Get(),
"Begin", "begin", nil,
target, options, true /* isBegin */, false, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
defer tabletenv.QueryStats.Record("BEGIN", time.Now())
if tsv.txThrottler.Throttle() {
// TODO(erez): I think this should be RESOURCE_EXHAUSTED.
return vterrors.Errorf(vtrpcpb.Code_UNAVAILABLE, "Transaction throttled")
}
transactionID, err = tsv.te.txPool.Begin(ctx, options)
logStats.TransactionID = transactionID
return err
},
)
return transactionID, err
}
// Commit commits the specified transaction.
func (tsv *TabletServer) Commit(ctx context.Context, target *querypb.Target, transactionID int64) (err error) {
return tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"Commit", "commit", nil,
target, nil, false /* isBegin */, true, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
defer tabletenv.QueryStats.Record("COMMIT", time.Now())
logStats.TransactionID = transactionID
return tsv.te.txPool.Commit(ctx, transactionID, tsv.messager)
},
)
}
// Rollback rollsback the specified transaction.
func (tsv *TabletServer) Rollback(ctx context.Context, target *querypb.Target, transactionID int64) (err error) {
return tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"Rollback", "rollback", nil,
target, nil, false /* isBegin */, true, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
defer tabletenv.QueryStats.Record("ROLLBACK", time.Now())
logStats.TransactionID = transactionID
return tsv.te.txPool.Rollback(ctx, transactionID)
},
)
}
// Prepare prepares the specified transaction.
func (tsv *TabletServer) Prepare(ctx context.Context, target *querypb.Target, transactionID int64, dtid string) (err error) {
return tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"Prepare", "prepare", nil,
target, nil, false /* isBegin */, true, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
txe := &TxExecutor{
ctx: ctx,
logStats: logStats,
te: tsv.te,
messager: tsv.messager,
}
return txe.Prepare(transactionID, dtid)
},
)
}
// CommitPrepared commits the prepared transaction.
func (tsv *TabletServer) CommitPrepared(ctx context.Context, target *querypb.Target, dtid string) (err error) {
return tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"CommitPrepared", "commit_prepared", nil,
target, nil, false /* isBegin */, true, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
txe := &TxExecutor{
ctx: ctx,
logStats: logStats,
te: tsv.te,
messager: tsv.messager,
}
return txe.CommitPrepared(dtid)
},
)
}
// RollbackPrepared commits the prepared transaction.
func (tsv *TabletServer) RollbackPrepared(ctx context.Context, target *querypb.Target, dtid string, originalID int64) (err error) {
return tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"RollbackPrepared", "rollback_prepared", nil,
target, nil, false /* isBegin */, true, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
txe := &TxExecutor{
ctx: ctx,
logStats: logStats,
te: tsv.te,
messager: tsv.messager,
}
return txe.RollbackPrepared(dtid, originalID)
},
)
}
// CreateTransaction creates the metadata for a 2PC transaction.
func (tsv *TabletServer) CreateTransaction(ctx context.Context, target *querypb.Target, dtid string, participants []*querypb.Target) (err error) {
return tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"CreateTransaction", "create_transaction", nil,
target, nil, true /* isBegin */, true, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
txe := &TxExecutor{
ctx: ctx,
logStats: logStats,
te: tsv.te,
messager: tsv.messager,
}
return txe.CreateTransaction(dtid, participants)
},
)
}
// StartCommit atomically commits the transaction along with the
// decision to commit the associated 2pc transaction.
func (tsv *TabletServer) StartCommit(ctx context.Context, target *querypb.Target, transactionID int64, dtid string) (err error) {
return tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"StartCommit", "start_commit", nil,
target, nil, false /* isBegin */, true, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
txe := &TxExecutor{
ctx: ctx,
logStats: logStats,
te: tsv.te,
messager: tsv.messager,
}
return txe.StartCommit(transactionID, dtid)
},
)
}
// SetRollback transitions the 2pc transaction to the Rollback state.
// If a transaction id is provided, that transaction is also rolled back.
func (tsv *TabletServer) SetRollback(ctx context.Context, target *querypb.Target, dtid string, transactionID int64) (err error) {
return tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"SetRollback", "set_rollback", nil,
target, nil, false /* isBegin */, true, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
txe := &TxExecutor{
ctx: ctx,
logStats: logStats,
te: tsv.te,
messager: tsv.messager,
}
return txe.SetRollback(dtid, transactionID)
},
)
}
// ConcludeTransaction deletes the 2pc transaction metadata
// essentially resolving it.
func (tsv *TabletServer) ConcludeTransaction(ctx context.Context, target *querypb.Target, dtid string) (err error) {
return tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"ConcludeTransaction", "conclude_transaction", nil,
target, nil, false /* isBegin */, true, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
txe := &TxExecutor{
ctx: ctx,
logStats: logStats,
te: tsv.te,
messager: tsv.messager,
}
return txe.ConcludeTransaction(dtid)
},
)
}
// ReadTransaction returns the metadata for the sepcified dtid.
func (tsv *TabletServer) ReadTransaction(ctx context.Context, target *querypb.Target, dtid string) (metadata *querypb.TransactionMetadata, err error) {
err = tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"ReadTransaction", "read_transaction", nil,
target, nil, false /* isBegin */, true, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
txe := &TxExecutor{
ctx: ctx,
logStats: logStats,
te: tsv.te,
messager: tsv.messager,
}
metadata, err = txe.ReadTransaction(dtid)
return err
},
)
return metadata, err
}
// Execute executes the query and returns the result as response.
func (tsv *TabletServer) Execute(ctx context.Context, target *querypb.Target, sql string, bindVariables map[string]*querypb.BindVariable, transactionID int64, options *querypb.ExecuteOptions) (result *sqltypes.Result, err error) {
allowOnShutdown := (transactionID != 0)
err = tsv.execRequest(
ctx, tsv.QueryTimeout.Get(),
"Execute", sql, bindVariables,
target, options, false /* isBegin */, allowOnShutdown,
func(ctx context.Context, logStats *tabletenv.LogStats) error {
if bindVariables == nil {
bindVariables = make(map[string]*querypb.BindVariable)
}
query, comments := sqlparser.SplitMarginComments(sql)
plan, err := tsv.qe.GetPlan(ctx, logStats, query, skipQueryPlanCache(options))
if err != nil {
return err
}
qre := &QueryExecutor{
query: query,
marginComments: comments,
bindVars: bindVariables,
transactionID: transactionID,
options: options,
plan: plan,
ctx: ctx,
logStats: logStats,
tsv: tsv,
}
extras := tsv.watcher.ComputeExtras(options)
result, err = qre.Execute()
if err != nil {
return err
}
result.Extras = extras
result = result.StripMetadata(sqltypes.IncludeFieldsOrDefault(options))
return nil
},
)
return result, err
}
// StreamExecute executes the query and streams the result.
// The first QueryResult will have Fields set (and Rows nil).
// The subsequent QueryResult will have Rows set (and Fields nil).
func (tsv *TabletServer) StreamExecute(ctx context.Context, target *querypb.Target, sql string, bindVariables map[string]*querypb.BindVariable, options *querypb.ExecuteOptions, callback func(*sqltypes.Result) error) (err error) {
return tsv.execRequest(
ctx, 0,
"StreamExecute", sql, bindVariables,
target, options, false /* isBegin */, false, /* allowOnShutdown */
func(ctx context.Context, logStats *tabletenv.LogStats) error {
if bindVariables == nil {
bindVariables = make(map[string]*querypb.BindVariable)
}
query, comments := sqlparser.SplitMarginComments(sql)
plan, err := tsv.qe.GetStreamPlan(query)
if err != nil {
return err
}
qre := &QueryExecutor{
query: query,
marginComments: comments,
bindVars: bindVariables,
options: options,
plan: plan,
ctx: ctx,
logStats: logStats,
tsv: tsv,
}
return qre.Stream(callback)
},
)
}
// ExecuteBatch executes a group of queries and returns their results as a list.
// ExecuteBatch can be called for an existing transaction, or it can be called with
// the AsTransaction flag which will execute all statements inside an independent
// transaction. If AsTransaction is true, TransactionId must be 0.
func (tsv *TabletServer) ExecuteBatch(ctx context.Context, target *querypb.Target, queries []*querypb.BoundQuery, asTransaction bool, transactionID int64, options *querypb.ExecuteOptions) (results []sqltypes.Result, err error) {
if len(queries) == 0 {