698 lines
17 KiB
Go
698 lines
17 KiB
Go
package networkdb
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import (
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"bytes"
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"crypto/rand"
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"encoding/hex"
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"fmt"
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"log"
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"math/big"
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rnd "math/rand"
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"net"
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"strings"
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"time"
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"github.com/hashicorp/memberlist"
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"github.com/sirupsen/logrus"
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)
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const (
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reapPeriod = 5 * time.Second
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retryInterval = 1 * time.Second
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nodeReapInterval = 24 * time.Hour
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nodeReapPeriod = 2 * time.Hour
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)
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type logWriter struct{}
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func (l *logWriter) Write(p []byte) (int, error) {
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str := string(p)
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str = strings.TrimSuffix(str, "\n")
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switch {
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case strings.HasPrefix(str, "[WARN] "):
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str = strings.TrimPrefix(str, "[WARN] ")
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logrus.Warn(str)
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case strings.HasPrefix(str, "[DEBUG] "):
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str = strings.TrimPrefix(str, "[DEBUG] ")
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logrus.Debug(str)
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case strings.HasPrefix(str, "[INFO] "):
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str = strings.TrimPrefix(str, "[INFO] ")
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logrus.Info(str)
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case strings.HasPrefix(str, "[ERR] "):
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str = strings.TrimPrefix(str, "[ERR] ")
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logrus.Warn(str)
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}
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return len(p), nil
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}
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// SetKey adds a new key to the key ring
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func (nDB *NetworkDB) SetKey(key []byte) {
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logrus.Debugf("Adding key %s", hex.EncodeToString(key)[0:5])
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nDB.Lock()
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defer nDB.Unlock()
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for _, dbKey := range nDB.config.Keys {
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if bytes.Equal(key, dbKey) {
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return
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}
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}
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nDB.config.Keys = append(nDB.config.Keys, key)
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if nDB.keyring != nil {
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nDB.keyring.AddKey(key)
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}
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}
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// SetPrimaryKey sets the given key as the primary key. This should have
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// been added apriori through SetKey
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func (nDB *NetworkDB) SetPrimaryKey(key []byte) {
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logrus.Debugf("Primary Key %s", hex.EncodeToString(key)[0:5])
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nDB.RLock()
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defer nDB.RUnlock()
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for _, dbKey := range nDB.config.Keys {
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if bytes.Equal(key, dbKey) {
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if nDB.keyring != nil {
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nDB.keyring.UseKey(dbKey)
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}
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break
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}
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}
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}
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// RemoveKey removes a key from the key ring. The key being removed
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// can't be the primary key
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func (nDB *NetworkDB) RemoveKey(key []byte) {
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logrus.Debugf("Remove Key %s", hex.EncodeToString(key)[0:5])
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nDB.Lock()
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defer nDB.Unlock()
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for i, dbKey := range nDB.config.Keys {
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if bytes.Equal(key, dbKey) {
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nDB.config.Keys = append(nDB.config.Keys[:i], nDB.config.Keys[i+1:]...)
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if nDB.keyring != nil {
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nDB.keyring.RemoveKey(dbKey)
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}
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break
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}
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}
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}
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func (nDB *NetworkDB) clusterInit() error {
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nDB.lastStatsTimestamp = time.Now()
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nDB.lastHealthTimestamp = nDB.lastStatsTimestamp
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config := memberlist.DefaultLANConfig()
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config.Name = nDB.config.NodeID
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config.BindAddr = nDB.config.BindAddr
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config.AdvertiseAddr = nDB.config.AdvertiseAddr
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config.UDPBufferSize = nDB.config.PacketBufferSize
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if nDB.config.BindPort != 0 {
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config.BindPort = nDB.config.BindPort
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}
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config.ProtocolVersion = memberlist.ProtocolVersion2Compatible
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config.Delegate = &delegate{nDB: nDB}
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config.Events = &eventDelegate{nDB: nDB}
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// custom logger that does not add time or date, so they are not
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// duplicated by logrus
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config.Logger = log.New(&logWriter{}, "", 0)
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var err error
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if len(nDB.config.Keys) > 0 {
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for i, key := range nDB.config.Keys {
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logrus.Debugf("Encryption key %d: %s", i+1, hex.EncodeToString(key)[0:5])
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}
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nDB.keyring, err = memberlist.NewKeyring(nDB.config.Keys, nDB.config.Keys[0])
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if err != nil {
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return err
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}
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config.Keyring = nDB.keyring
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}
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nDB.networkBroadcasts = &memberlist.TransmitLimitedQueue{
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NumNodes: func() int {
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nDB.RLock()
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num := len(nDB.nodes)
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nDB.RUnlock()
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return num
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},
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RetransmitMult: config.RetransmitMult,
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}
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nDB.nodeBroadcasts = &memberlist.TransmitLimitedQueue{
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NumNodes: func() int {
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nDB.RLock()
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num := len(nDB.nodes)
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nDB.RUnlock()
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return num
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},
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RetransmitMult: config.RetransmitMult,
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}
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mlist, err := memberlist.Create(config)
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if err != nil {
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return fmt.Errorf("failed to create memberlist: %v", err)
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}
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nDB.stopCh = make(chan struct{})
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nDB.memberlist = mlist
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for _, trigger := range []struct {
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interval time.Duration
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fn func()
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}{
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{reapPeriod, nDB.reapState},
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{config.GossipInterval, nDB.gossip},
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{config.PushPullInterval, nDB.bulkSyncTables},
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{retryInterval, nDB.reconnectNode},
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{nodeReapPeriod, nDB.reapDeadNode},
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} {
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t := time.NewTicker(trigger.interval)
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go nDB.triggerFunc(trigger.interval, t.C, nDB.stopCh, trigger.fn)
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nDB.tickers = append(nDB.tickers, t)
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}
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return nil
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}
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func (nDB *NetworkDB) retryJoin(members []string, stop <-chan struct{}) {
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t := time.NewTicker(retryInterval)
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defer t.Stop()
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for {
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select {
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case <-t.C:
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if _, err := nDB.memberlist.Join(members); err != nil {
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logrus.Errorf("Failed to join memberlist %s on retry: %v", members, err)
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continue
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}
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if err := nDB.sendNodeEvent(NodeEventTypeJoin); err != nil {
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logrus.Errorf("failed to send node join on retry: %v", err)
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continue
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}
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return
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case <-stop:
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return
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}
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}
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}
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func (nDB *NetworkDB) clusterJoin(members []string) error {
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mlist := nDB.memberlist
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if _, err := mlist.Join(members); err != nil {
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// In case of failure, keep retrying join until it succeeds or the cluster is shutdown.
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go nDB.retryJoin(members, nDB.stopCh)
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return fmt.Errorf("could not join node to memberlist: %v", err)
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}
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if err := nDB.sendNodeEvent(NodeEventTypeJoin); err != nil {
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return fmt.Errorf("failed to send node join: %v", err)
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}
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return nil
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}
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func (nDB *NetworkDB) clusterLeave() error {
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mlist := nDB.memberlist
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if err := nDB.sendNodeEvent(NodeEventTypeLeave); err != nil {
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logrus.Errorf("failed to send node leave: %v", err)
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}
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if err := mlist.Leave(time.Second); err != nil {
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return err
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}
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close(nDB.stopCh)
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for _, t := range nDB.tickers {
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t.Stop()
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}
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return mlist.Shutdown()
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}
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func (nDB *NetworkDB) triggerFunc(stagger time.Duration, C <-chan time.Time, stop <-chan struct{}, f func()) {
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// Use a random stagger to avoid syncronizing
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randStagger := time.Duration(uint64(rnd.Int63()) % uint64(stagger))
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select {
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case <-time.After(randStagger):
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case <-stop:
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return
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}
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for {
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select {
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case <-C:
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f()
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case <-stop:
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return
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}
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}
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}
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func (nDB *NetworkDB) reapDeadNode() {
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nDB.Lock()
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defer nDB.Unlock()
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for _, nodeMap := range []map[string]*node{
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nDB.failedNodes,
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nDB.leftNodes,
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} {
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for id, n := range nodeMap {
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if n.reapTime > nodeReapPeriod {
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n.reapTime -= nodeReapPeriod
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continue
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}
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logrus.Debugf("Garbage collect node %v", n.Name)
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delete(nodeMap, id)
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}
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}
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}
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func (nDB *NetworkDB) reconnectNode() {
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nDB.RLock()
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if len(nDB.failedNodes) == 0 {
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nDB.RUnlock()
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return
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}
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nodes := make([]*node, 0, len(nDB.failedNodes))
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for _, n := range nDB.failedNodes {
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nodes = append(nodes, n)
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}
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nDB.RUnlock()
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node := nodes[randomOffset(len(nodes))]
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addr := net.UDPAddr{IP: node.Addr, Port: int(node.Port)}
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if _, err := nDB.memberlist.Join([]string{addr.String()}); err != nil {
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return
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}
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if err := nDB.sendNodeEvent(NodeEventTypeJoin); err != nil {
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return
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}
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logrus.Debugf("Initiating bulk sync with node %s after reconnect", node.Name)
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nDB.bulkSync([]string{node.Name}, true)
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}
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// For timing the entry deletion in the repaer APIs that doesn't use monotonic clock
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// source (time.Now, Sub etc.) should be avoided. Hence we use reapTime in every
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// entry which is set initially to reapInterval and decremented by reapPeriod every time
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// the reaper runs. NOTE nDB.reapTableEntries updates the reapTime with a readlock. This
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// is safe as long as no other concurrent path touches the reapTime field.
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func (nDB *NetworkDB) reapState() {
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// The reapTableEntries leverage the presence of the network so garbage collect entries first
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nDB.reapTableEntries()
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nDB.reapNetworks()
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}
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func (nDB *NetworkDB) reapNetworks() {
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nDB.Lock()
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for _, nn := range nDB.networks {
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for id, n := range nn {
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if n.leaving {
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if n.reapTime <= 0 {
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delete(nn, id)
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continue
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}
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n.reapTime -= reapPeriod
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}
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}
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}
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nDB.Unlock()
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}
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func (nDB *NetworkDB) reapTableEntries() {
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var nodeNetworks []string
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// This is best effort, if the list of network changes will be picked up in the next cycle
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nDB.RLock()
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for nid := range nDB.networks[nDB.config.NodeID] {
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nodeNetworks = append(nodeNetworks, nid)
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}
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nDB.RUnlock()
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cycleStart := time.Now()
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// In order to avoid blocking the database for a long time, apply the garbage collection logic by network
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// The lock is taken at the beginning of the cycle and the deletion is inline
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for _, nid := range nodeNetworks {
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nDB.Lock()
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nDB.indexes[byNetwork].WalkPrefix(fmt.Sprintf("/%s", nid), func(path string, v interface{}) bool {
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// timeCompensation compensate in case the lock took some time to be released
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timeCompensation := time.Since(cycleStart)
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entry, ok := v.(*entry)
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if !ok || !entry.deleting {
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return false
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}
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// In this check we are adding an extra 1 second to guarantee that when the number is truncated to int32 to fit the packet
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// for the tableEvent the number is always strictly > 1 and never 0
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if entry.reapTime > reapPeriod+timeCompensation+time.Second {
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entry.reapTime -= reapPeriod + timeCompensation
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return false
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}
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params := strings.Split(path[1:], "/")
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nid := params[0]
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tname := params[1]
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key := params[2]
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okTable, okNetwork := nDB.deleteEntry(nid, tname, key)
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if !okTable {
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logrus.Errorf("Table tree delete failed, entry with key:%s does not exists in the table:%s network:%s", key, tname, nid)
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}
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if !okNetwork {
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logrus.Errorf("Network tree delete failed, entry with key:%s does not exists in the network:%s table:%s", key, nid, tname)
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}
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return false
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})
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nDB.Unlock()
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}
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}
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func (nDB *NetworkDB) gossip() {
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networkNodes := make(map[string][]string)
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nDB.RLock()
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thisNodeNetworks := nDB.networks[nDB.config.NodeID]
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for nid := range thisNodeNetworks {
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networkNodes[nid] = nDB.networkNodes[nid]
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}
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printStats := time.Since(nDB.lastStatsTimestamp) >= nDB.config.StatsPrintPeriod
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printHealth := time.Since(nDB.lastHealthTimestamp) >= nDB.config.HealthPrintPeriod
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nDB.RUnlock()
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if printHealth {
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healthScore := nDB.memberlist.GetHealthScore()
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if healthScore != 0 {
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logrus.Warnf("NetworkDB stats %v(%v) - healthscore:%d (connectivity issues)", nDB.config.Hostname, nDB.config.NodeID, healthScore)
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}
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nDB.lastHealthTimestamp = time.Now()
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}
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for nid, nodes := range networkNodes {
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mNodes := nDB.mRandomNodes(3, nodes)
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bytesAvail := nDB.config.PacketBufferSize - compoundHeaderOverhead
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nDB.RLock()
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network, ok := thisNodeNetworks[nid]
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nDB.RUnlock()
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if !ok || network == nil {
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// It is normal for the network to be removed
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// between the time we collect the network
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// attachments of this node and processing
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// them here.
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continue
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}
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broadcastQ := network.tableBroadcasts
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if broadcastQ == nil {
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logrus.Errorf("Invalid broadcastQ encountered while gossiping for network %s", nid)
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continue
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}
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msgs := broadcastQ.GetBroadcasts(compoundOverhead, bytesAvail)
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// Collect stats and print the queue info, note this code is here also to have a view of the queues empty
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network.qMessagesSent += len(msgs)
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if printStats {
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logrus.Infof("NetworkDB stats %v(%v) - netID:%s leaving:%t netPeers:%d entries:%d Queue qLen:%d netMsg/s:%d",
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nDB.config.Hostname, nDB.config.NodeID,
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nid, network.leaving, broadcastQ.NumNodes(), network.entriesNumber, broadcastQ.NumQueued(),
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network.qMessagesSent/int((nDB.config.StatsPrintPeriod/time.Second)))
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network.qMessagesSent = 0
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}
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if len(msgs) == 0 {
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continue
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}
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// Create a compound message
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compound := makeCompoundMessage(msgs)
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for _, node := range mNodes {
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nDB.RLock()
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mnode := nDB.nodes[node]
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nDB.RUnlock()
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if mnode == nil {
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break
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}
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// Send the compound message
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if err := nDB.memberlist.SendBestEffort(&mnode.Node, compound); err != nil {
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logrus.Errorf("Failed to send gossip to %s: %s", mnode.Addr, err)
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}
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}
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}
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// Reset the stats
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if printStats {
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nDB.lastStatsTimestamp = time.Now()
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}
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}
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func (nDB *NetworkDB) bulkSyncTables() {
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var networks []string
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nDB.RLock()
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for nid, network := range nDB.networks[nDB.config.NodeID] {
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if network.leaving {
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continue
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}
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networks = append(networks, nid)
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}
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nDB.RUnlock()
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for {
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if len(networks) == 0 {
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break
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}
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nid := networks[0]
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networks = networks[1:]
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nDB.RLock()
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nodes := nDB.networkNodes[nid]
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nDB.RUnlock()
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// No peer nodes on this network. Move on.
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if len(nodes) == 0 {
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continue
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}
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completed, err := nDB.bulkSync(nodes, false)
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if err != nil {
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logrus.Errorf("periodic bulk sync failure for network %s: %v", nid, err)
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continue
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}
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// Remove all the networks for which we have
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// successfully completed bulk sync in this iteration.
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updatedNetworks := make([]string, 0, len(networks))
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for _, nid := range networks {
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var found bool
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for _, completedNid := range completed {
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if nid == completedNid {
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found = true
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break
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}
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}
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if !found {
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updatedNetworks = append(updatedNetworks, nid)
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}
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}
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networks = updatedNetworks
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}
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}
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func (nDB *NetworkDB) bulkSync(nodes []string, all bool) ([]string, error) {
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if !all {
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// Get 2 random nodes. 2nd node will be tried if the bulk sync to
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// 1st node fails.
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nodes = nDB.mRandomNodes(2, nodes)
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}
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if len(nodes) == 0 {
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return nil, nil
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}
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var err error
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var networks []string
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for _, node := range nodes {
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if node == nDB.config.NodeID {
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continue
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}
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logrus.Debugf("%v(%v): Initiating bulk sync with node %v", nDB.config.Hostname, nDB.config.NodeID, node)
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networks = nDB.findCommonNetworks(node)
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err = nDB.bulkSyncNode(networks, node, true)
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// if its periodic bulksync stop after the first successful sync
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if !all && err == nil {
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break
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}
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if err != nil {
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err = fmt.Errorf("bulk sync to node %s failed: %v", node, err)
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logrus.Warn(err.Error())
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}
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}
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if err != nil {
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|
return nil, err
|
|
}
|
|
|
|
return networks, nil
|
|
}
|
|
|
|
// Bulk sync all the table entries belonging to a set of networks to a
|
|
// single peer node. It can be unsolicited or can be in response to an
|
|
// unsolicited bulk sync
|
|
func (nDB *NetworkDB) bulkSyncNode(networks []string, node string, unsolicited bool) error {
|
|
var msgs [][]byte
|
|
|
|
var unsolMsg string
|
|
if unsolicited {
|
|
unsolMsg = "unsolicited"
|
|
}
|
|
|
|
logrus.Debugf("%v(%v): Initiating %s bulk sync for networks %v with node %s",
|
|
nDB.config.Hostname, nDB.config.NodeID, unsolMsg, networks, node)
|
|
|
|
nDB.RLock()
|
|
mnode := nDB.nodes[node]
|
|
if mnode == nil {
|
|
nDB.RUnlock()
|
|
return nil
|
|
}
|
|
|
|
for _, nid := range networks {
|
|
nDB.indexes[byNetwork].WalkPrefix(fmt.Sprintf("/%s", nid), func(path string, v interface{}) bool {
|
|
entry, ok := v.(*entry)
|
|
if !ok {
|
|
return false
|
|
}
|
|
|
|
eType := TableEventTypeCreate
|
|
if entry.deleting {
|
|
eType = TableEventTypeDelete
|
|
}
|
|
|
|
params := strings.Split(path[1:], "/")
|
|
tEvent := TableEvent{
|
|
Type: eType,
|
|
LTime: entry.ltime,
|
|
NodeName: entry.node,
|
|
NetworkID: nid,
|
|
TableName: params[1],
|
|
Key: params[2],
|
|
Value: entry.value,
|
|
// The duration in second is a float that below would be truncated
|
|
ResidualReapTime: int32(entry.reapTime.Seconds()),
|
|
}
|
|
|
|
msg, err := encodeMessage(MessageTypeTableEvent, &tEvent)
|
|
if err != nil {
|
|
logrus.Errorf("Encode failure during bulk sync: %#v", tEvent)
|
|
return false
|
|
}
|
|
|
|
msgs = append(msgs, msg)
|
|
return false
|
|
})
|
|
}
|
|
nDB.RUnlock()
|
|
|
|
// Create a compound message
|
|
compound := makeCompoundMessage(msgs)
|
|
|
|
bsm := BulkSyncMessage{
|
|
LTime: nDB.tableClock.Time(),
|
|
Unsolicited: unsolicited,
|
|
NodeName: nDB.config.NodeID,
|
|
Networks: networks,
|
|
Payload: compound,
|
|
}
|
|
|
|
buf, err := encodeMessage(MessageTypeBulkSync, &bsm)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to encode bulk sync message: %v", err)
|
|
}
|
|
|
|
nDB.Lock()
|
|
ch := make(chan struct{})
|
|
nDB.bulkSyncAckTbl[node] = ch
|
|
nDB.Unlock()
|
|
|
|
err = nDB.memberlist.SendReliable(&mnode.Node, buf)
|
|
if err != nil {
|
|
nDB.Lock()
|
|
delete(nDB.bulkSyncAckTbl, node)
|
|
nDB.Unlock()
|
|
|
|
return fmt.Errorf("failed to send a TCP message during bulk sync: %v", err)
|
|
}
|
|
|
|
// Wait on a response only if it is unsolicited.
|
|
if unsolicited {
|
|
startTime := time.Now()
|
|
t := time.NewTimer(30 * time.Second)
|
|
select {
|
|
case <-t.C:
|
|
logrus.Errorf("Bulk sync to node %s timed out", node)
|
|
case <-ch:
|
|
logrus.Debugf("%v(%v): Bulk sync to node %s took %s", nDB.config.Hostname, nDB.config.NodeID, node, time.Since(startTime))
|
|
}
|
|
t.Stop()
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// Returns a random offset between 0 and n
|
|
func randomOffset(n int) int {
|
|
if n == 0 {
|
|
return 0
|
|
}
|
|
|
|
val, err := rand.Int(rand.Reader, big.NewInt(int64(n)))
|
|
if err != nil {
|
|
logrus.Errorf("Failed to get a random offset: %v", err)
|
|
return 0
|
|
}
|
|
|
|
return int(val.Int64())
|
|
}
|
|
|
|
// mRandomNodes is used to select up to m random nodes. It is possible
|
|
// that less than m nodes are returned.
|
|
func (nDB *NetworkDB) mRandomNodes(m int, nodes []string) []string {
|
|
n := len(nodes)
|
|
mNodes := make([]string, 0, m)
|
|
OUTER:
|
|
// Probe up to 3*n times, with large n this is not necessary
|
|
// since k << n, but with small n we want search to be
|
|
// exhaustive
|
|
for i := 0; i < 3*n && len(mNodes) < m; i++ {
|
|
// Get random node
|
|
idx := randomOffset(n)
|
|
node := nodes[idx]
|
|
|
|
if node == nDB.config.NodeID {
|
|
continue
|
|
}
|
|
|
|
// Check if we have this node already
|
|
for j := 0; j < len(mNodes); j++ {
|
|
if node == mNodes[j] {
|
|
continue OUTER
|
|
}
|
|
}
|
|
|
|
// Append the node
|
|
mNodes = append(mNodes, node)
|
|
}
|
|
|
|
return mNodes
|
|
}
|