// Return the next chunk of binlog events; skip to next binary log file if need be; return empty result only
// if reached end of binary logs
func getNextBinlogEventsChunk(instance *Instance, startingCoordinates BinlogCoordinates, numEmptyBinlogs int) ([]BinlogEvent, error) {
if numEmptyBinlogs > maxEmptyBinlogFiles {
log.Debugf("Reached maxEmptyBinlogFiles (%d) at %+v", maxEmptyBinlogFiles, startingCoordinates)
// Give up and return empty results
return []BinlogEvent{}, nil
}
coordinatesExceededCurrent := false
switch startingCoordinates.Type {
case BinaryLog:
coordinatesExceededCurrent = instance.SelfBinlogCoordinates.FileSmallerThan(&startingCoordinates)
case RelayLog:
coordinatesExceededCurrent = instance.RelaylogCoordinates.FileSmallerThan(&startingCoordinates)
}
if coordinatesExceededCurrent {
// We're past the last file. This is a non-error: there are no more events.
log.Debugf("Coordinates overflow: %+v; terminating search", startingCoordinates)
return []BinlogEvent{}, nil
}
events, err := readBinlogEventsChunk(&instance.Key, startingCoordinates)
if err != nil {
return events, err
}
if len(events) > 0 {
log.Debugf("Returning %d events at %+v", len(events), startingCoordinates)
return events, nil
}
// events are empty
if nextCoordinates, err := instance.GetNextBinaryLog(startingCoordinates); err == nil {
log.Debugf("Recursing into %+v", nextCoordinates)
return getNextBinlogEventsChunk(instance, nextCoordinates, numEmptyBinlogs+1)
}
// on error
return events, err
}
// deployIfNotAlreadyDeployed will issue given sql queries that are not already known to be deployed.
// This iterates both lists (to-run and already-deployed) and also verifies no contraditions.
func deployIfNotAlreadyDeployed(db *sql.DB, queries []string, deployedQueries []string, deploymentType string, fatalOnError bool) error {
tx, err := db.Begin()
if err != nil {
log.Fatale(err)
}
// Ugly workaround ahead.
// Origin of this workaround is the existence of some "timestamp NOT NULL," column definitions,
// where in NO_ZERO_IN_DATE,NO_ZERO_DATE sql_mode are invalid (since default is implicitly "0")
// This means installation of orchestrator fails on such configured servers, and in particular on 5.7
// where this setting is the dfault.
// For purpose of backwards compatability, what we do is force sql_mode to be more relaxed, create the schemas
// along with the "invalid" definition, and then go ahead and fix those definitions via following ALTER statements.
// My bad.
originalSqlMode := ""
err = tx.QueryRow(`select @@session.sql_mode`).Scan(&originalSqlMode)
if _, err := tx.Exec(`set @@session.sql_mode=REPLACE(@@session.sql_mode, 'NO_ZERO_DATE', '')`); err != nil {
log.Fatale(err)
}
if _, err := tx.Exec(`set @@session.sql_mode=REPLACE(@@session.sql_mode, 'NO_ZERO_IN_DATE', '')`); err != nil {
log.Fatale(err)
}
for i, query := range queries {
queryAlreadyExecuted := false
// While iterating 'queries', also iterate 'deployedQueries'. Expect identity
if len(deployedQueries) > i {
if deployedQueries[i] != query {
log.Fatalf("initOrchestratorDB() PANIC: non matching %s queries between deployment requests and _orchestrator_db_deployment. Please execute 'orchestrator -c reset-internal-db-deployment'", deploymentType)
}
queryAlreadyExecuted = true
}
if queryAlreadyExecuted {
continue
}
if i == 0 {
log.Debugf("sql_mode is: %+v", originalSqlMode)
}
if config.Config.SmartOrchestratorDatabaseUpdate {
log.Debugf("initOrchestratorDB executing: %.80s", strings.TrimSpace(strings.Replace(query, "\n", "", -1)))
}
if fatalOnError {
if _, err := tx.Exec(query); err != nil {
return log.Fatalf("Cannot initiate orchestrator: %+v", err)
}
} else {
tx.Exec(query)
// And ignore any error
}
writeInternalDeployment(db, deploymentType, query, i)
}
if _, err := tx.Exec(`set session sql_mode=?`, originalSqlMode); err != nil {
log.Fatale(err)
}
if err := tx.Commit(); err != nil {
log.Fatale(err)
}
return nil
}
// Attempt to resolve a hostname. This may return a database cached hostname or otherwise
// it may resolve the hostname via CNAME
func ResolveHostname(hostname string) (string, error) {
hostname = strings.TrimSpace(hostname)
if hostname == "" {
return hostname, errors.New("Will not resolve empty hostname")
}
if strings.Contains(hostname, ",") {
return hostname, fmt.Errorf("Will not resolve multi-hostname: %+v", hostname)
}
if (&InstanceKey{Hostname: hostname}).IsDetached() {
return hostname, fmt.Errorf("Will not resolve detached hostname: %+v", hostname)
}
// First go to lightweight cache
if resolvedHostname, found := hostnameResolvesLightweightCache.Get(hostname); found {
return resolvedHostname.(string), nil
}
if !hostnameResolvesLightweightCacheLoadedOnceFromDB {
// A continuous-discovery will first make sure to load all resolves from DB.
// However cli does not do so.
// Anyway, it seems like the cache was not loaded from DB. Before doing real resolves,
// let's try and get the resolved hostname from database.
if !HostnameResolveMethodIsNone() {
if resolvedHostname, err := ReadResolvedHostname(hostname); err == nil && resolvedHostname != "" {
hostnameResolvesLightweightCache.Set(hostname, resolvedHostname, 0)
return resolvedHostname, nil
}
}
}
// Unfound: resolve!
log.Debugf("Hostname unresolved yet: %s", hostname)
resolvedHostname, err := resolveHostname(hostname)
if config.Config.RejectHostnameResolvePattern != "" {
// Reject, don't even cache
if matched, _ := regexp.MatchString(config.Config.RejectHostnameResolvePattern, resolvedHostname); matched {
log.Warningf("ResolveHostname: %+v resolved to %+v but rejected due to RejectHostnameResolvePattern '%+v'", hostname, resolvedHostname, config.Config.RejectHostnameResolvePattern)
return hostname, nil
}
}
if err != nil {
// Problem. What we'll do is cache the hostname for just one minute, so as to avoid flooding requests
// on one hand, yet make it refresh shortly on the other hand. Anyway do not write to database.
hostnameResolvesLightweightCache.Set(hostname, resolvedHostname, time.Minute)
return hostname, err
}
// Good result! Cache it, also to DB
log.Debugf("Cache hostname resolve %s as %s", hostname, resolvedHostname)
UpdateResolvedHostname(hostname, resolvedHostname)
return resolvedHostname, nil
}
func execCmd(commandText string, arguments ...string) (*exec.Cmd, string, error) {
commandBytes := []byte(commandText)
tmpFile, err := ioutil.TempFile("", "orchestrator-process-cmd-")
if err != nil {
return nil, "", log.Errore(err)
}
ioutil.WriteFile(tmpFile.Name(), commandBytes, 0644)
log.Debugf("execCmd: %s", commandText)
shellArguments := append([]string{}, tmpFile.Name())
shellArguments = append(shellArguments, arguments...)
log.Debugf("%+v", shellArguments)
return exec.Command("bash", shellArguments...), tmpFile.Name(), nil
//return exec.Command(commandText, arguments...) , "", nil
}
func InitGraphiteMetrics() error {
if config.Config.GraphiteAddr == "" {
return nil
}
if config.Config.GraphitePath == "" {
return log.Errorf("No graphite path provided (see GraphitePath config variable). Will not log to graphite")
}
addr, err := net.ResolveTCPAddr("tcp", config.Config.GraphiteAddr)
if err != nil {
return log.Errore(err)
}
graphitePathHostname := process.ThisHostname
if config.Config.GraphiteConvertHostnameDotsToUnderscores {
graphitePathHostname = strings.Replace(graphitePathHostname, ".", "_", -1)
}
graphitePath := config.Config.GraphitePath
graphitePath = strings.Replace(graphitePath, "{hostname}", graphitePathHostname, -1)
log.Debugf("Will log to graphite on %+v, %+v", config.Config.GraphiteAddr, graphitePath)
go func() {
go graphite.Graphite(metrics.DefaultRegistry, 1*time.Minute, graphitePath, addr)
for range graphiteCallbackTick {
for _, f := range graphiteTickCallbacks {
go f()
}
}
}()
return nil
}
// checkAndRecoverDeadIntermediateMaster checks a given analysis, decides whether to take action, and possibly takes action
// Returns true when action was taken.
func checkAndRecoverDeadIntermediateMaster(analysisEntry inst.ReplicationAnalysis, candidateInstanceKey *inst.InstanceKey, forceInstanceRecovery bool, skipProcesses bool) (bool, *TopologyRecovery, error) {
if !(forceInstanceRecovery || analysisEntry.ClusterDetails.HasAutomatedIntermediateMasterRecovery) {
return false, nil, nil
}
topologyRecovery, err := AttemptRecoveryRegistration(&analysisEntry, !forceInstanceRecovery, !forceInstanceRecovery)
if topologyRecovery == nil {
log.Debugf("topology_recovery: found an active or recent recovery on %+v. Will not issue another RecoverDeadIntermediateMaster.", analysisEntry.AnalyzedInstanceKey)
return false, nil, err
}
// That's it! We must do recovery!
recoverDeadIntermediateMasterCounter.Inc(1)
promotedSlave, err := RecoverDeadIntermediateMaster(topologyRecovery, skipProcesses)
if promotedSlave != nil {
// success
recoverDeadIntermediateMasterSuccessCounter.Inc(1)
if !skipProcesses {
// Execute post intermediate-master-failover processes
topologyRecovery.SuccessorKey = &promotedSlave.Key
executeProcesses(config.Config.PostIntermediateMasterFailoverProcesses, "PostIntermediateMasterFailoverProcesses", topologyRecovery, false)
}
} else {
recoverDeadIntermediateMasterFailureCounter.Inc(1)
}
return true, topologyRecovery, err
}
// SkipQuery skip a single query in a failed replication instance
func SkipQuery(instanceKey *InstanceKey) (*Instance, error) {
instance, err := ReadTopologyInstance(instanceKey)
if err != nil {
return instance, log.Errore(err)
}
if !instance.IsSlave() {
return instance, fmt.Errorf("instance is not a slave: %+v", instanceKey)
}
if instance.Slave_SQL_Running {
return instance, fmt.Errorf("Slave SQL thread is running on %+v", instanceKey)
}
if instance.LastSQLError == "" {
return instance, fmt.Errorf("No SQL error on %+v", instanceKey)
}
if *config.RuntimeCLIFlags.Noop {
return instance, fmt.Errorf("noop: aborting skip-query operation on %+v; signalling error but nothing went wrong.", *instanceKey)
}
log.Debugf("Skipping one query on %+v", instanceKey)
if instance.UsingOracleGTID {
err = skipQueryOracleGtid(instance)
} else if instance.UsingMariaDBGTID {
return instance, log.Errorf("%+v is replicating with MariaDB GTID. To skip a query first disable GTID, then skip, then enable GTID again", *instanceKey)
} else {
err = skipQueryClassic(instance)
}
if err != nil {
return instance, log.Errore(err)
}
AuditOperation("skip-query", instanceKey, "Skipped one query")
return StartSlave(instanceKey)
}
// CheckAndRecover is the main entry point for the recovery mechanism
func CheckAndRecover(specificInstance *inst.InstanceKey, candidateInstanceKey *inst.InstanceKey, skipProcesses bool) (recoveryAttempted bool, promotedSlaveKey *inst.InstanceKey, err error) {
replicationAnalysis, err := inst.GetReplicationAnalysis("", true, true)
if err != nil {
return false, nil, log.Errore(err)
}
if *config.RuntimeCLIFlags.Noop {
log.Debugf("--noop provided; will not execute processes")
skipProcesses = true
}
for _, analysisEntry := range replicationAnalysis {
if specificInstance != nil {
// We are looking for a specific instance; if this is not the one, skip!
if !specificInstance.Equals(&analysisEntry.AnalyzedInstanceKey) {
continue
}
}
if analysisEntry.IsDowntimed && specificInstance == nil {
// Only recover a downtimed server if explicitly requested
continue
}
if specificInstance != nil {
// force mode. Keep it synchronuous
var topologyRecovery *TopologyRecovery
recoveryAttempted, topologyRecovery, err = executeCheckAndRecoverFunction(analysisEntry, candidateInstanceKey, true, skipProcesses)
if topologyRecovery != nil {
promotedSlaveKey = topologyRecovery.SuccessorKey
}
} else {
go executeCheckAndRecoverFunction(analysisEntry, candidateInstanceKey, false, skipProcesses)
}
}
return recoveryAttempted, promotedSlaveKey, err
}
// executeAgentCommand requests an agent to execute a command via HTTP api
func executeAgentCommand(hostname string, command string, onResponse *func([]byte)) (Agent, error) {
agent, token, err := readAgentBasicInfo(hostname)
if err != nil {
return agent, err
}
// All seems to be in order. Now make some inquiries from orchestrator-agent service:
uri := baseAgentUri(agent.Hostname, agent.Port)
var fullCommand string
if strings.Contains(command, "?") {
fullCommand = fmt.Sprintf("%s&token=%s", command, token)
} else {
fullCommand = fmt.Sprintf("%s?token=%s", command, token)
}
log.Debugf("orchestrator-agent command: %s", fullCommand)
agentCommandUri := fmt.Sprintf("%s/%s", uri, fullCommand)
body, err := readResponse(httpGet(agentCommandUri))
if err != nil {
return agent, log.Errore(err)
}
if onResponse != nil {
(*onResponse)(body)
}
auditAgentOperation("agent-command", &agent, command)
return agent, err
}
// StopSlavesNicely will attemt to stop all given slaves nicely, up to timeout
func StopSlavesNicely(slaves [](*Instance), timeout time.Duration) [](*Instance) {
refreshedSlaves := [](*Instance){}
log.Debugf("Stopping %d slaves nicely", len(slaves))
// use concurrency but wait for all to complete
barrier := make(chan *Instance)
for _, slave := range slaves {
slave := slave
go func() {
updatedSlave := &slave
// Signal completed slave
defer func() { barrier <- *updatedSlave }()
// Wait your turn to read a slave
ExecuteOnTopology(func() {
StopSlaveNicely(&slave.Key, timeout)
slave, _ = StopSlave(&slave.Key)
updatedSlave = &slave
})
}()
}
for range slaves {
refreshedSlaves = append(refreshedSlaves, <-barrier)
}
return refreshedSlaves
}
// baseAgentUri returns the base URI for accessing an agent
func baseAgentUri(agentHostname string, agentPort int) string {
protocol := "http"
if config.Config.AgentsUseSSL {
protocol = "https"
}
uri := fmt.Sprintf("%s://%s:%d/api", protocol, agentHostname, agentPort)
log.Debugf("orchestrator-agent uri: %s", uri)
return uri
}
// checkAndRecoverDeadMaster checks a given analysis, decides whether to take action, and possibly takes action
// Returns true when action was taken.
func checkAndRecoverDeadMaster(analysisEntry inst.ReplicationAnalysis, candidateInstanceKey *inst.InstanceKey, forceInstanceRecovery bool, skipProcesses bool) (bool, *TopologyRecovery, error) {
if !(forceInstanceRecovery || analysisEntry.ClusterDetails.HasAutomatedMasterRecovery) {
return false, nil, nil
}
topologyRecovery, err := AttemptRecoveryRegistration(&analysisEntry, !forceInstanceRecovery, !forceInstanceRecovery)
if topologyRecovery == nil {
log.Debugf("topology_recovery: found an active or recent recovery on %+v. Will not issue another RecoverDeadMaster.", analysisEntry.AnalyzedInstanceKey)
return false, nil, err
}
// That's it! We must do recovery!
log.Debugf("topology_recovery: will handle DeadMaster event on %+v", analysisEntry.ClusterDetails.ClusterName)
recoverDeadMasterCounter.Inc(1)
promotedSlave, lostSlaves, err := RecoverDeadMaster(topologyRecovery, skipProcesses)
topologyRecovery.LostSlaves.AddInstances(lostSlaves)
if promotedSlave != nil {
promotedSlave, err = replacePromotedSlaveWithCandidate(&analysisEntry.AnalyzedInstanceKey, promotedSlave, candidateInstanceKey)
topologyRecovery.AddError(err)
}
// And this is the end; whether successful or not, we're done.
ResolveRecovery(topologyRecovery, promotedSlave)
if promotedSlave != nil {
// Success!
recoverDeadMasterSuccessCounter.Inc(1)
if config.Config.ApplyMySQLPromotionAfterMasterFailover {
log.Debugf("topology_recovery: - RecoverDeadMaster: will apply MySQL changes to promoted master")
inst.ResetSlaveOperation(&promotedSlave.Key)
inst.SetReadOnly(&promotedSlave.Key, false)
}
if !skipProcesses {
// Execute post master-failover processes
executeProcesses(config.Config.PostMasterFailoverProcesses, "PostMasterFailoverProcesses", topologyRecovery, false)
}
} else {
recoverDeadMasterFailureCounter.Inc(1)
}
return true, topologyRecovery, err
}
// nextEvent will return the next event entry from binary logs; it will automatically skip to next
// binary log if need be.
// Internally, it uses the cachedEvents array, so that it does not go to the MySQL server upon each call.
// Returns nil upon reaching end of binary logs.
func (this *BinlogEventCursor) nextEvent(numEmptyEventsEvents int) (*BinlogEvent, error) {
if numEmptyEventsEvents > maxEmptyEventsEvents {
log.Debugf("End of logs. currentEventIndex: %d, nextCoordinates: %+v", this.currentEventIndex, this.nextCoordinates)
// End of logs
return nil, nil
}
if len(this.cachedEvents) == 0 {
// Cache exhausted; get next bulk of entries and return the next entry
nextFileCoordinates, err := this.nextCoordinates.NextFileCoordinates()
if err != nil {
return nil, err
}
log.Debugf("zero cached events, next file: %+v", nextFileCoordinates)
this.cachedEvents, err = this.fetchNextEvents(nextFileCoordinates)
if err != nil {
return nil, err
}
this.currentEventIndex = -1
// While this seems recursive do note that recursion level is at most 1, since we either have
// entires in the next binlog (no further recursion) or we don't (immediate termination)
return this.nextEvent(numEmptyEventsEvents + 1)
}
if this.currentEventIndex+1 < len(this.cachedEvents) {
// We have enough cache to go by
this.currentEventIndex++
event := &this.cachedEvents[this.currentEventIndex]
this.nextCoordinates = event.NextBinlogCoordinates()
return event, nil
} else {
// Cache exhausted; get next bulk of entries and return the next entry
var err error
this.cachedEvents, err = this.fetchNextEvents(this.cachedEvents[len(this.cachedEvents)-1].NextBinlogCoordinates())
if err != nil {
return nil, err
}
this.currentEventIndex = -1
// While this seems recursive do note that recursion level is at most 1, since we either have
// entires in the next binlog (no further recursion) or we don't (immediate termination)
return this.nextEvent(numEmptyEventsEvents + 1)
}
}
// checkAndExecuteFailureDetectionProcesses tries to register for failure detection and potentially executes
// failure-detection processes.
func checkAndExecuteFailureDetectionProcesses(analysisEntry inst.ReplicationAnalysis, skipProcesses bool) (processesExecutionAttempted bool, err error) {
if ok, _ := AttemptFailureDetectionRegistration(&analysisEntry); !ok {
return false, nil
}
log.Debugf("topology_recovery: detected %+v failure on %+v", analysisEntry.Analysis, analysisEntry.AnalyzedInstanceKey)
// Execute on-detection processes
if skipProcesses {
return false, nil
}
err = executeProcesses(config.Config.OnFailureDetectionProcesses, "OnFailureDetectionProcesses", NewTopologyRecovery(analysisEntry), true)
return true, err
}
// AuditOperation creates and writes a new audit entry by given params
func AuditOperation(auditType string, instanceKey *InstanceKey, message string) error {
if instanceKey == nil {
instanceKey = &InstanceKey{}
}
clusterName := ""
if instanceKey.Hostname != "" {
clusterName, _ = GetClusterName(instanceKey)
}
if config.Config.AuditLogFile != "" {
go func() error {
f, err := os.OpenFile(config.Config.AuditLogFile, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0600)
if err != nil {
return log.Errore(err)
}
defer f.Close()
text := fmt.Sprintf("%s\t%s\t%s\t%d\t[%s]\t%s\t\n", time.Now().Format(log.TimeFormat), auditType, instanceKey.Hostname, instanceKey.Port, clusterName, message)
if _, err = f.WriteString(text); err != nil {
return log.Errore(err)
}
return nil
}()
}
_, err := db.ExecOrchestrator(`
insert
into audit (
audit_timestamp, audit_type, hostname, port, cluster_name, message
) VALUES (
NOW(), ?, ?, ?, ?, ?
)
`,
auditType,
instanceKey.Hostname,
instanceKey.Port,
clusterName,
message,
)
if err != nil {
return log.Errore(err)
}
logMessage := fmt.Sprintf("auditType:%s instance:%s cluster:%s message:%s", auditType, instanceKey.DisplayString(), clusterName, message)
if syslogWriter != nil {
go func() {
syslogWriter.Info(logMessage)
}()
}
log.Debugf(logMessage)
auditOperationCounter.Inc(1)
return err
}
// handleDiscoveryRequests iterates the discoveryInstanceKeys channel and calls upon
// instance discovery per entry.
func handleDiscoveryRequests() {
for instanceKey := range discoveryInstanceKeys {
// Possibly this used to be the elected node, but has been demoted, while still
// the queue is full.
// Just don't process the queue when not elected.
if isElectedNode {
go discoverInstance(instanceKey)
} else {
log.Debugf("Node apparently demoted. Skipping discovery of %+v. Remaining queue size: %+v", instanceKey, len(discoveryInstanceKeys))
}
}
}
func postReadAdjustments() {
if Config.MySQLOrchestratorCredentialsConfigFile != "" {
mySQLConfig := struct {
Client struct {
User string
Password string
}
}{}
err := gcfg.ReadFileInto(&mySQLConfig, Config.MySQLOrchestratorCredentialsConfigFile)
if err != nil {
log.Fatalf("Failed to parse gcfg data from file: %+v", err)
} else {
log.Debugf("Parsed orchestrator credentials from %s", Config.MySQLOrchestratorCredentialsConfigFile)
Config.MySQLOrchestratorUser = mySQLConfig.Client.User
Config.MySQLOrchestratorPassword = mySQLConfig.Client.Password
}
}
if Config.MySQLTopologyCredentialsConfigFile != "" {
mySQLConfig := struct {
Client struct {
User string
Password string
}
}{}
err := gcfg.ReadFileInto(&mySQLConfig, Config.MySQLTopologyCredentialsConfigFile)
if err != nil {
log.Fatalf("Failed to parse gcfg data from file: %+v", err)
} else {
log.Debugf("Parsed topology credentials from %s", Config.MySQLTopologyCredentialsConfigFile)
Config.MySQLTopologyUser = mySQLConfig.Client.User
Config.MySQLTopologyPassword = mySQLConfig.Client.Password
}
}
if Config.RecoveryPeriodBlockSeconds == 0 && Config.RecoveryPeriodBlockMinutes > 0 {
// RecoveryPeriodBlockSeconds is a newer addition that overrides RecoveryPeriodBlockMinutes
// The code does not consider RecoveryPeriodBlockMinutes anymore, but RecoveryPeriodBlockMinutes
// still supported in config file for backwards compatibility
Config.RecoveryPeriodBlockSeconds = Config.RecoveryPeriodBlockMinutes * 60
}
}
func getLastPseudoGTIDEntryInInstance(instance *Instance, maxBinlogCoordinates *BinlogCoordinates, exhaustiveSearch bool) (*BinlogCoordinates, string, error) {
// Look for last GTID in instance:
currentBinlog := instance.SelfBinlogCoordinates
var err error = nil
for err == nil {
log.Debugf("Searching for latest pseudo gtid entry in binlog %+v of %+v", currentBinlog.LogFile, instance.Key)
resultCoordinates, entryInfo, err := getLastPseudoGTIDEntryInBinlog(&instance.Key, currentBinlog.LogFile, BinaryLog, maxBinlogCoordinates)
if err != nil {
return nil, "", err
}
if resultCoordinates != nil {
log.Debugf("Found pseudo gtid entry in %+v, %+v", instance.Key, resultCoordinates)
return resultCoordinates, entryInfo, err
}
if !exhaustiveSearch {
break
}
currentBinlog, err = currentBinlog.PreviousFileCoordinates()
}
return nil, "", log.Errorf("Cannot find pseudo GTID entry in binlogs of %+v", instance.Key)
}
func getLastPseudoGTIDEntryInRelayLogs(instance *Instance, recordedInstanceRelayLogCoordinates BinlogCoordinates, exhaustiveSearch bool) (*BinlogCoordinates, string, error) {
// Look for last GTID in relay logs:
// Since MySQL does not provide with a SHOW RELAY LOGS command, we heuristically srtart from current
// relay log (indiciated by Relay_log_file) and walk backwards.
// Eventually we will hit a relay log name which does not exist.
currentRelayLog := recordedInstanceRelayLogCoordinates
var err error = nil
for err == nil {
log.Debugf("Searching for latest pseudo gtid entry in relaylog %+v of %+v, up to pos %+v", currentRelayLog.LogFile, instance.Key, recordedInstanceRelayLogCoordinates)
if resultCoordinates, entryInfo, err := getLastPseudoGTIDEntryInBinlog(&instance.Key, currentRelayLog.LogFile, RelayLog, &recordedInstanceRelayLogCoordinates); err != nil {
return nil, "", err
} else if resultCoordinates != nil {
log.Debugf("Found pseudo gtid entry in %+v, %+v", instance.Key, resultCoordinates)
return resultCoordinates, entryInfo, err
}
if !exhaustiveSearch {
break
}
currentRelayLog, err = currentRelayLog.PreviousFileCoordinates()
}
return nil, "", log.Errorf("Cannot find pseudo GTID entry in relay logs of %+v", instance.Key)
}
// checkAndRecoverDeadCoMaster checks a given analysis, decides whether to take action, and possibly takes action
// Returns true when action was taken.
func checkAndRecoverDeadCoMaster(analysisEntry inst.ReplicationAnalysis, candidateInstanceKey *inst.InstanceKey, forceInstanceRecovery bool, skipProcesses bool) (bool, *TopologyRecovery, error) {
failedInstanceKey := &analysisEntry.AnalyzedInstanceKey
if !(forceInstanceRecovery || analysisEntry.ClusterDetails.HasAutomatedMasterRecovery) {
return false, nil, nil
}
topologyRecovery, err := AttemptRecoveryRegistration(&analysisEntry, !forceInstanceRecovery, !forceInstanceRecovery)
if topologyRecovery == nil {
log.Debugf("topology_recovery: found an active or recent recovery on %+v. Will not issue another RecoverDeadCoMaster.", analysisEntry.AnalyzedInstanceKey)
return false, nil, err
}
// That's it! We must do recovery!
recoverDeadCoMasterCounter.Inc(1)
promotedSlave, lostSlaves, err := RecoverDeadCoMaster(topologyRecovery, skipProcesses)
ResolveRecovery(topologyRecovery, promotedSlave)
if promotedSlave == nil {
inst.AuditOperation("recover-dead-co-master", failedInstanceKey, "Failure: no slave promoted.")
} else {
inst.AuditOperation("recover-dead-co-master", failedInstanceKey, fmt.Sprintf("promoted: %+v", promotedSlave.Key))
}
topologyRecovery.LostSlaves.AddInstances(lostSlaves)
if promotedSlave != nil {
// success
recoverDeadCoMasterSuccessCounter.Inc(1)
if config.Config.ApplyMySQLPromotionAfterMasterFailover {
log.Debugf("topology_recovery: - RecoverDeadMaster: will apply MySQL changes to promoted master")
inst.SetReadOnly(&promotedSlave.Key, false)
}
if !skipProcesses {
// Execute post intermediate-master-failover processes
topologyRecovery.SuccessorKey = &promotedSlave.Key
executeProcesses(config.Config.PostMasterFailoverProcesses, "PostMasterFailoverProcesses", topologyRecovery, false)
}
} else {
recoverDeadCoMasterFailureCounter.Inc(1)
}
return true, topologyRecovery, err
}
func (this *PostponedFunctionsContainer) InvokePostponed() (err error) {
if len(this.PostponedFunctions) == 0 {
return
}
log.Debugf("PostponedFunctionsContainer: invoking %+v postponed functions", len(this.PostponedFunctions))
for _, postponedFunction := range this.PostponedFunctions {
ferr := postponedFunction()
if err == nil {
err = ferr
}
}
return err
}
// SearchEntryInInstanceBinlogs will search for a specific text entry within the binary logs of a given instance.
func SearchEntryInInstanceBinlogs(instance *Instance, entryText string, monotonicPseudoGTIDEntries bool) (*BinlogCoordinates, error) {
cacheKey := getInstanceBinlogEntryKey(instance, entryText)
coords, found := instanceBinlogEntryCache.Get(cacheKey)
if found {
// This is wonderful. We can skip the tedious GTID search in the binary log
log.Debugf("Found instance Pseudo GTID entry coordinates in cache: %+v, %+v, %+v", instance.Key, entryText, coords)
return coords.(*BinlogCoordinates), nil
}
// Look for GTID entry in given instance:
log.Debugf("Searching for given pseudo gtid entry in %+v. monotonicPseudoGTIDEntries=%+v", instance.Key, monotonicPseudoGTIDEntries)
currentBinlog := instance.SelfBinlogCoordinates
var err error = nil
for {
log.Debugf("Searching for given pseudo gtid entry in binlog %+v of %+v", currentBinlog.LogFile, instance.Key)
// loop iteration per binary log. This might turn to be a heavyweight operation. We wish to throttle the operation such that
// the instance does not suffer. If it is a slave, we will only act as long as it's not lagging too much.
if instance.SlaveRunning() {
for {
log.Debugf("%+v is a replicating slave. Verifying lag", instance.Key)
instance, err = ReadTopologyInstance(&instance.Key)
if err != nil {
break
}
if instance.HasReasonableMaintenanceReplicationLag() {
// is good to go!
break
}
log.Debugf("lag is too high on %+v. Throttling the search for pseudo gtid entry", instance.Key)
time.Sleep(time.Duration(config.Config.ReasonableMaintenanceReplicationLagSeconds) * time.Second)
}
}
var resultCoordinates BinlogCoordinates
var found bool = false
resultCoordinates, found, err = SearchEntryInBinlog(&instance.Key, currentBinlog.LogFile, entryText, monotonicPseudoGTIDEntries)
if err != nil {
break
}
if found {
log.Debugf("Matched entry in %+v: %+v", instance.Key, resultCoordinates)
instanceBinlogEntryCache.Set(cacheKey, &resultCoordinates, 0)
return &resultCoordinates, nil
}
// Got here? Unfound. Keep looking
currentBinlog, err = currentBinlog.PreviousFileCoordinates()
if err != nil {
break
}
log.Debugf("- Will move next to binlog %+v", currentBinlog.LogFile)
}
return nil, log.Errorf("Cannot match pseudo GTID entry in binlogs of %+v; err: %+v", instance.Key, err)
}
// acceptSignals registers for OS signals
func acceptSignals() {
c := make(chan os.Signal, 1)
signal.Notify(c, syscall.SIGHUP)
go func() {
for sig := range c {
switch sig {
case syscall.SIGHUP:
log.Debugf("Received SIGHUP. Reloading configuration")
config.Reload()
inst.AuditOperation("reload-configuration", nil, "Triggered via SIGHUP")
}
}
}()
}
// StartSlaves will do concurrent start-slave
func StartSlaves(slaves [](*Instance)) {
// use concurrency but wait for all to complete
log.Debugf("Starting %d slaves", len(slaves))
barrier := make(chan InstanceKey)
for _, instance := range slaves {
instance := instance
go func() {
// Signal compelted slave
defer func() { barrier <- instance.Key }()
// Wait your turn to read a slave
ExecuteOnTopology(func() { StartSlave(&instance.Key) })
}()
}
for range slaves {
<-barrier
}
}
func ApplyPoolInstances(pool string, instancesList string) error {
var instanceKeys [](*InstanceKey)
if instancesList != "" {
instancesStrings := strings.Split(instancesList, ",")
for _, instanceString := range instancesStrings {
instanceKey, err := ParseInstanceKeyLoose(instanceString)
log.Debugf("%+v", instanceKey)
if err != nil {
return log.Errore(err)
}
instanceKeys = append(instanceKeys, instanceKey)
}
}
writePoolInstances(pool, instanceKeys)
return nil
}
// discoverInstance will attempt discovering an instance (unless it is already up to date) and will
// list down its master and slaves (if any) for further discovery.
func discoverInstance(instanceKey inst.InstanceKey) {
instanceKey.Formalize()
if !instanceKey.IsValid() {
return
}
if existsInCacheError := recentDiscoveryOperationKeys.Add(instanceKey.DisplayString(), true, cache.DefaultExpiration); existsInCacheError != nil {
// Just recently attempted
return
}
instance, found, err := inst.ReadInstance(&instanceKey)
if found && instance.IsUpToDate && instance.IsLastCheckValid {
// we've already discovered this one. Skip!
return
}
discoveriesCounter.Inc(1)
// First we've ever heard of this instance. Continue investigation:
instance, err = inst.ReadTopologyInstance(&instanceKey)
// panic can occur (IO stuff). Therefore it may happen
// that instance is nil. Check it.
if instance == nil {
failedDiscoveriesCounter.Inc(1)
log.Warningf("instance is nil in discoverInstance. key=%+v, error=%+v", instanceKey, err)
return
}
log.Debugf("Discovered host: %+v, master: %+v, version: %+v", instance.Key, instance.MasterKey, instance.Version)
if !isElectedNode {
// Maybe this node was elected before, but isn't elected anymore.
// If not elected, stop drilling up/down the topology
return
}
// Investigate slaves:
for _, slaveKey := range instance.SlaveHosts.GetInstanceKeys() {
slaveKey := slaveKey
discoveryInstanceKeys <- slaveKey
}
// Investigate master:
discoveryInstanceKeys <- instance.MasterKey
}
// readInternalDeployments reads orchestrator db deployment statements that are known to have been executed
func readInternalDeployments() (baseDeployments []string, patchDeployments []string, err error) {
if !config.Config.SmartOrchestratorDatabaseUpdate {
return baseDeployments, patchDeployments, nil
}
query := fmt.Sprintf(`
select
deployment_type,
sql_statement
from
_orchestrator_db_deployment
order by
deployment_id
`)
db, err := OpenOrchestrator()
if err != nil {
log.Fatalf("Cannot initiate orchestrator internal deployment: %+v", err)
}
err = sqlutils.QueryRowsMap(db, query, func(m sqlutils.RowMap) error {
deploymentType := m.GetString("deployment_type")
sqlStatement := m.GetString("sql_statement")
if deploymentType == "base" {
baseDeployments = append(baseDeployments, sqlStatement)
} else if deploymentType == "patch" {
patchDeployments = append(patchDeployments, sqlStatement)
} else {
log.Fatalf("Unknown deployment type (%+v) encountered in _orchestrator_db_deployment", deploymentType)
}
return nil
})
if err != nil {
log.Debugf("Deploying internal orchestrator tables to fix the above; this is a one time operation")
// Table does not exist? Create it for first time
for _, query := range internalDBDeploymentSQL {
if _, err = execInternal(db, query); err != nil {
log.Fatalf("Cannot initiate orchestrator internal deployment: %+v", err)
}
}
}
return baseDeployments, patchDeployments, nil
}
// RefreshTopologyInstances will do a blocking (though concurrent) refresh of all given instances
func RefreshTopologyInstances(instances [](*Instance)) {
// use concurrency but wait for all to complete
barrier := make(chan InstanceKey)
for _, instance := range instances {
instance := instance
go func() {
// Signal completed slave
defer func() { barrier <- instance.Key }()
// Wait your turn to read a slave
ExecuteOnTopology(func() {
log.Debugf("... reading instance: %+v", instance.Key)
ReadTopologyInstance(&instance.Key)
})
}()
}
for range instances {
<-barrier
}
}
// SkipToNextBinaryLog changes master position to beginning of next binlog
// USE WITH CARE!
// Use case is binlog servers where the master was gone & replaced by another.
func SkipToNextBinaryLog(instanceKey *InstanceKey) (*Instance, error) {
instance, err := ReadTopologyInstance(instanceKey)
if err != nil {
return instance, log.Errore(err)
}
nextFileCoordinates, err := instance.ExecBinlogCoordinates.NextFileCoordinates()
if err != nil {
return instance, log.Errore(err)
}
nextFileCoordinates.LogPos = 4
log.Debugf("Will skip replication on %+v to next binary log: %+v", instance.Key, nextFileCoordinates.LogFile)
instance, err = ChangeMasterTo(&instance.Key, &instance.MasterKey, &nextFileCoordinates, false, GTIDHintNeutral)
if err != nil {
return instance, log.Errore(err)
}
AuditOperation("skip-binlog", instanceKey, fmt.Sprintf("Skipped replication to next binary log: %+v", nextFileCoordinates.LogFile))
return StartSlave(instanceKey)
}
// ContinuousAgentsPoll starts an asynchronuous infinite process where agents are
// periodically investigated and their status captured, and long since unseen agents are
// purged and forgotten.
func ContinuousAgentsPoll() {
log.Infof("Starting continuous agents poll")
go discoverSeededAgents()
tick := time.Tick(time.Duration(config.Config.DiscoveryPollSeconds) * time.Second)
caretakingTick := time.Tick(time.Hour)
for range tick {
agentsHosts, _ := agent.ReadOutdatedAgentsHosts()
log.Debugf("outdated agents hosts: %+v", agentsHosts)
for _, hostname := range agentsHosts {
go pollAgent(hostname)
}
// See if we should also forget agents (lower frequency)
select {
case <-caretakingTick:
agent.ForgetLongUnseenAgents()
agent.FailStaleSeeds()
default:
}
}
}