/
jetstream_cluster.go
5465 lines (4896 loc) · 147 KB
/
jetstream_cluster.go
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// Copyright 2020-2022 The NATS Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package server
import (
"bytes"
"encoding/binary"
"encoding/json"
"errors"
"fmt"
"math"
"math/rand"
"path"
"reflect"
"sort"
"strings"
"sync/atomic"
"time"
"github.com/klauspost/compress/s2"
"github.com/nats-io/nuid"
)
// jetStreamCluster holds information about the meta group and stream assignments.
type jetStreamCluster struct {
// The metacontroller raftNode.
meta RaftNode
// For stream and consumer assignments. All servers will have this be the same.
// ACCOUNT -> STREAM -> Stream Assignment -> Consumers
streams map[string]map[string]*streamAssignment
// Signals meta-leader should check the stream assignments.
streamsCheck bool
// Server.
s *Server
// Internal client.
c *client
// Processing assignment results.
streamResults *subscription
consumerResults *subscription
// System level request to have the leader stepdown.
stepdown *subscription
// System level requests to remove a peer.
peerRemove *subscription
}
// Used to guide placement of streams and meta controllers in clustered JetStream.
type Placement struct {
Cluster string `json:"cluster"`
Tags []string `json:"tags,omitempty"`
}
// Define types of the entry.
type entryOp uint8
// ONLY ADD TO THE END, DO NOT INSERT IN BETWEEN WILL BREAK SERVER INTEROP.
const (
// Meta ops.
assignStreamOp entryOp = iota
assignConsumerOp
removeStreamOp
removeConsumerOp
// Stream ops.
streamMsgOp
purgeStreamOp
deleteMsgOp
// Consumer ops.
updateDeliveredOp
updateAcksOp
// Compressed consumer assignments.
assignCompressedConsumerOp
// Filtered Consumer skip.
updateSkipOp
// Update Stream.
updateStreamOp
// For updating information on pending pull requests.
addPendingRequest
removePendingRequest
)
// raftGroups are controlled by the metagroup controller.
// The raftGroups will house streams and consumers.
type raftGroup struct {
Name string `json:"name"`
Peers []string `json:"peers"`
Storage StorageType `json:"store"`
Preferred string `json:"preferred,omitempty"`
// Internal
node RaftNode
}
// streamAssignment is what the meta controller uses to assign streams to peers.
type streamAssignment struct {
Client *ClientInfo `json:"client,omitempty"`
Created time.Time `json:"created"`
Config *StreamConfig `json:"stream"`
Group *raftGroup `json:"group"`
Sync string `json:"sync"`
Subject string `json:"subject"`
Reply string `json:"reply"`
Restore *StreamState `json:"restore_state,omitempty"`
// Internal
consumers map[string]*consumerAssignment
responded bool
err error
}
// consumerAssignment is what the meta controller uses to assign consumers to streams.
type consumerAssignment struct {
Client *ClientInfo `json:"client,omitempty"`
Created time.Time `json:"created"`
Name string `json:"name"`
Stream string `json:"stream"`
Config *ConsumerConfig `json:"consumer"`
Group *raftGroup `json:"group"`
Subject string `json:"subject"`
Reply string `json:"reply"`
State *ConsumerState `json:"state,omitempty"`
// Internal
responded bool
deleted bool
pending bool
err error
}
// streamPurge is what the stream leader will replicate when purging a stream.
type streamPurge struct {
Client *ClientInfo `json:"client,omitempty"`
Stream string `json:"stream"`
LastSeq uint64 `json:"last_seq"`
Subject string `json:"subject"`
Reply string `json:"reply"`
Request *JSApiStreamPurgeRequest `json:"request,omitempty"`
}
// streamMsgDelete is what the stream leader will replicate when deleting a message.
type streamMsgDelete struct {
Client *ClientInfo `json:"client,omitempty"`
Stream string `json:"stream"`
Seq uint64 `json:"seq"`
NoErase bool `json:"no_erase,omitempty"`
Subject string `json:"subject"`
Reply string `json:"reply"`
}
const (
defaultStoreDirName = "_js_"
defaultMetaGroupName = "_meta_"
defaultMetaFSBlkSize = 1024 * 1024
)
// Returns information useful in mixed mode.
func (s *Server) trackedJetStreamServers() (js, total int) {
s.mu.Lock()
defer s.mu.Unlock()
if !s.running || !s.eventsEnabled() {
return -1, -1
}
s.nodeToInfo.Range(func(k, v interface{}) bool {
si := v.(nodeInfo)
if si.js {
js++
}
total++
return true
})
return js, total
}
func (s *Server) getJetStreamCluster() (*jetStream, *jetStreamCluster) {
s.mu.Lock()
shutdown := s.shutdown
js := s.js
s.mu.Unlock()
if shutdown || js == nil {
return nil, nil
}
js.mu.RLock()
cc := js.cluster
js.mu.RUnlock()
if cc == nil {
return nil, nil
}
return js, cc
}
func (s *Server) JetStreamIsClustered() bool {
js := s.getJetStream()
if js == nil {
return false
}
return js.isClustered()
}
func (s *Server) JetStreamIsLeader() bool {
js := s.getJetStream()
if js == nil {
return false
}
js.mu.RLock()
defer js.mu.RUnlock()
return js.cluster.isLeader()
}
func (s *Server) JetStreamIsCurrent() bool {
js := s.getJetStream()
if js == nil {
return false
}
js.mu.RLock()
defer js.mu.RUnlock()
return js.cluster.isCurrent()
}
func (s *Server) JetStreamSnapshotMeta() error {
js := s.getJetStream()
if js == nil {
return NewJSNotEnabledError()
}
js.mu.RLock()
cc := js.cluster
isLeader := cc.isLeader()
meta := cc.meta
js.mu.RUnlock()
if !isLeader {
return errNotLeader
}
return meta.InstallSnapshot(js.metaSnapshot())
}
func (s *Server) JetStreamStepdownStream(account, stream string) error {
js, cc := s.getJetStreamCluster()
if js == nil {
return NewJSNotEnabledError()
}
if cc == nil {
return NewJSClusterNotActiveError()
}
// Grab account
acc, err := s.LookupAccount(account)
if err != nil {
return err
}
// Grab stream
mset, err := acc.lookupStream(stream)
if err != nil {
return err
}
if node := mset.raftNode(); node != nil && node.Leader() {
node.StepDown()
}
return nil
}
func (s *Server) JetStreamSnapshotStream(account, stream string) error {
js, cc := s.getJetStreamCluster()
if js == nil {
return NewJSNotEnabledForAccountError()
}
if cc == nil {
return NewJSClusterNotActiveError()
}
// Grab account
acc, err := s.LookupAccount(account)
if err != nil {
return err
}
// Grab stream
mset, err := acc.lookupStream(stream)
if err != nil {
return err
}
mset.mu.RLock()
if !mset.node.Leader() {
mset.mu.RUnlock()
return NewJSNotEnabledForAccountError()
}
n := mset.node
mset.mu.RUnlock()
return n.InstallSnapshot(mset.stateSnapshot())
}
func (s *Server) JetStreamClusterPeers() []string {
js := s.getJetStream()
if js == nil {
return nil
}
js.mu.RLock()
defer js.mu.RUnlock()
cc := js.cluster
if !cc.isLeader() {
return nil
}
peers := cc.meta.Peers()
var nodes []string
for _, p := range peers {
si, ok := s.nodeToInfo.Load(p.ID)
if !ok || si == nil {
continue
}
ni := si.(nodeInfo)
// Ignore if offline, no JS, or no current stats have been received.
if ni.offline || !ni.js || ni.stats == nil {
continue
}
nodes = append(nodes, si.(nodeInfo).name)
}
return nodes
}
// Read lock should be held.
func (cc *jetStreamCluster) isLeader() bool {
if cc == nil {
// Non-clustered mode
return true
}
return cc.meta != nil && cc.meta.Leader()
}
// isCurrent will determine if this node is a leader or an up to date follower.
// Read lock should be held.
func (cc *jetStreamCluster) isCurrent() bool {
if cc == nil {
// Non-clustered mode
return true
}
if cc.meta == nil {
return false
}
return cc.meta.Current()
}
// isStreamCurrent will determine if this node is a participant for the stream and if its up to date.
// Read lock should be held.
func (cc *jetStreamCluster) isStreamCurrent(account, stream string) bool {
if cc == nil {
// Non-clustered mode
return true
}
as := cc.streams[account]
if as == nil {
return false
}
sa := as[stream]
if sa == nil {
return false
}
rg := sa.Group
if rg == nil || rg.node == nil {
return false
}
isCurrent := rg.node.Current()
if isCurrent {
// Check if we are processing a snapshot and are catching up.
acc, err := cc.s.LookupAccount(account)
if err != nil {
return false
}
mset, err := acc.lookupStream(stream)
if err != nil {
return false
}
if mset.isCatchingUp() {
return false
}
}
return isCurrent
}
func (a *Account) getJetStreamFromAccount() (*Server, *jetStream, *jsAccount) {
a.mu.RLock()
jsa := a.js
a.mu.RUnlock()
if jsa == nil {
return nil, nil, nil
}
jsa.mu.RLock()
js := jsa.js
jsa.mu.RUnlock()
if js == nil {
return nil, nil, nil
}
js.mu.RLock()
s := js.srv
js.mu.RUnlock()
return s, js, jsa
}
func (s *Server) JetStreamIsStreamLeader(account, stream string) bool {
js, cc := s.getJetStreamCluster()
if js == nil || cc == nil {
return false
}
js.mu.RLock()
defer js.mu.RUnlock()
return cc.isStreamLeader(account, stream)
}
func (a *Account) JetStreamIsStreamLeader(stream string) bool {
s, js, jsa := a.getJetStreamFromAccount()
if s == nil || js == nil || jsa == nil {
return false
}
js.mu.RLock()
defer js.mu.RUnlock()
return js.cluster.isStreamLeader(a.Name, stream)
}
func (s *Server) JetStreamIsStreamCurrent(account, stream string) bool {
js, cc := s.getJetStreamCluster()
if js == nil {
return false
}
js.mu.RLock()
defer js.mu.RUnlock()
return cc.isStreamCurrent(account, stream)
}
func (a *Account) JetStreamIsConsumerLeader(stream, consumer string) bool {
s, js, jsa := a.getJetStreamFromAccount()
if s == nil || js == nil || jsa == nil {
return false
}
js.mu.RLock()
defer js.mu.RUnlock()
return js.cluster.isConsumerLeader(a.Name, stream, consumer)
}
func (s *Server) JetStreamIsConsumerLeader(account, stream, consumer string) bool {
js, cc := s.getJetStreamCluster()
if js == nil || cc == nil {
return false
}
js.mu.RLock()
defer js.mu.RUnlock()
return cc.isConsumerLeader(account, stream, consumer)
}
func (s *Server) enableJetStreamClustering() error {
if !s.isRunning() {
return nil
}
js := s.getJetStream()
if js == nil {
return NewJSNotEnabledForAccountError()
}
// Already set.
if js.cluster != nil {
return nil
}
s.Noticef("Starting JetStream cluster")
// We need to determine if we have a stable cluster name and expected number of servers.
s.Debugf("JetStream cluster checking for stable cluster name and peers")
hasLeafNodeSystemShare := s.canExtendOtherDomain()
if s.isClusterNameDynamic() && !hasLeafNodeSystemShare {
return errors.New("JetStream cluster requires cluster name")
}
if s.configuredRoutes() == 0 && !hasLeafNodeSystemShare {
return errors.New("JetStream cluster requires configured routes or solicited leafnode for the system account")
}
return js.setupMetaGroup()
}
// isClustered returns if we are clustered.
// Lock should not be held.
func (js *jetStream) isClustered() bool {
js.mu.RLock()
isClustered := js.cluster != nil
js.mu.RUnlock()
return isClustered
}
func (js *jetStream) setupMetaGroup() error {
s := js.srv
s.Noticef("Creating JetStream metadata controller")
// Setup our WAL for the metagroup.
sysAcc := s.SystemAccount()
storeDir := path.Join(js.config.StoreDir, sysAcc.Name, defaultStoreDirName, defaultMetaGroupName)
fs, err := newFileStore(
FileStoreConfig{StoreDir: storeDir, BlockSize: defaultMetaFSBlkSize, AsyncFlush: false},
StreamConfig{Name: defaultMetaGroupName, Storage: FileStorage},
)
if err != nil {
s.Errorf("Error creating filestore: %v", err)
return err
}
cfg := &RaftConfig{Name: defaultMetaGroupName, Store: storeDir, Log: fs}
// If we are soliciting leafnode connections and we are sharing a system account and do not disable it with a hint,
// we want to move to observer mode so that we extend the solicited cluster or supercluster but do not form our own.
cfg.Observer = s.canExtendOtherDomain() && s.opts.JetStreamExtHint != jsNoExtend
var bootstrap bool
if ps, err := readPeerState(storeDir); err != nil {
s.Noticef("JetStream cluster bootstrapping")
bootstrap = true
peers := s.ActivePeers()
s.Debugf("JetStream cluster initial peers: %+v", peers)
if err := s.bootstrapRaftNode(cfg, peers, false); err != nil {
return err
}
if cfg.Observer {
s.Noticef("Turning JetStream metadata controller Observer Mode on")
}
} else {
s.Noticef("JetStream cluster recovering state")
// correlate the value of observer with observations from a previous run.
if cfg.Observer {
switch ps.domainExt {
case extExtended:
s.Noticef("Keeping JetStream metadata controller Observer Mode on - due to previous contact")
case extNotExtended:
s.Noticef("Turning JetStream metadata controller Observer Mode off - due to previous contact")
cfg.Observer = false
case extUndetermined:
s.Noticef("Turning JetStream metadata controller Observer Mode on - no previous contact")
s.Noticef("In cases where JetStream will not be extended")
s.Noticef("and waiting for leader election until first contact is not acceptable,")
s.Noticef(`manually disable Observer Mode by setting the JetStream Option "extension_hint: %s"`, jsNoExtend)
}
} else {
// To track possible configuration changes, responsible for an altered value of cfg.Observer,
// set extension state to undetermined.
ps.domainExt = extUndetermined
if err := writePeerState(storeDir, ps); err != nil {
return err
}
}
}
// Start up our meta node.
n, err := s.startRaftNode(cfg)
if err != nil {
s.Warnf("Could not start metadata controller: %v", err)
return err
}
// If we are bootstrapped with no state, start campaign early.
if bootstrap {
n.Campaign()
}
c := s.createInternalJetStreamClient()
sacc := s.SystemAccount()
js.mu.Lock()
defer js.mu.Unlock()
js.cluster = &jetStreamCluster{
meta: n,
streams: make(map[string]map[string]*streamAssignment),
s: s,
c: c,
}
c.registerWithAccount(sacc)
js.srv.startGoRoutine(js.monitorCluster)
return nil
}
func (js *jetStream) getMetaGroup() RaftNode {
js.mu.RLock()
defer js.mu.RUnlock()
if js.cluster == nil {
return nil
}
return js.cluster.meta
}
func (js *jetStream) server() *Server {
js.mu.RLock()
s := js.srv
js.mu.RUnlock()
return s
}
// Will respond if we do not think we have a metacontroller leader.
func (js *jetStream) isLeaderless() bool {
js.mu.RLock()
defer js.mu.RUnlock()
cc := js.cluster
if cc == nil || cc.meta == nil {
return false
}
// If we don't have a leader.
// Make sure we have been running for enough time.
if cc.meta.GroupLeader() == _EMPTY_ && time.Since(cc.meta.Created()) > lostQuorumInterval {
return true
}
return false
}
// Will respond iff we are a member and we know we have no leader.
func (js *jetStream) isGroupLeaderless(rg *raftGroup) bool {
if rg == nil {
return false
}
js.mu.RLock()
defer js.mu.RUnlock()
cc := js.cluster
// If we are not a member we can not say..
if !rg.isMember(cc.meta.ID()) {
return false
}
// Single peer groups always have a leader if we are here.
if rg.node == nil {
return false
}
// If we don't have a leader.
if rg.node.GroupLeader() == _EMPTY_ {
if rg.node.HadPreviousLeader() {
return true
}
// Make sure we have been running for enough time.
if time.Since(rg.node.Created()) > lostQuorumInterval {
return true
}
}
return false
}
func (s *Server) JetStreamIsStreamAssigned(account, stream string) bool {
js, cc := s.getJetStreamCluster()
if js == nil || cc == nil {
return false
}
acc, _ := s.LookupAccount(account)
if acc == nil {
return false
}
return cc.isStreamAssigned(acc, stream)
}
// streamAssigned informs us if this server has this stream assigned.
func (jsa *jsAccount) streamAssigned(stream string) bool {
jsa.mu.RLock()
js, acc := jsa.js, jsa.account
jsa.mu.RUnlock()
if js == nil {
return false
}
js.mu.RLock()
assigned := js.cluster.isStreamAssigned(acc, stream)
js.mu.RUnlock()
return assigned
}
// Read lock should be held.
func (cc *jetStreamCluster) isStreamAssigned(a *Account, stream string) bool {
// Non-clustered mode always return true.
if cc == nil {
return true
}
as := cc.streams[a.Name]
if as == nil {
return false
}
sa := as[stream]
if sa == nil {
return false
}
rg := sa.Group
if rg == nil {
return false
}
// Check if we are the leader of this raftGroup assigned to the stream.
ourID := cc.meta.ID()
for _, peer := range rg.Peers {
if peer == ourID {
return true
}
}
return false
}
// Read lock should be held.
func (cc *jetStreamCluster) isStreamLeader(account, stream string) bool {
// Non-clustered mode always return true.
if cc == nil {
return true
}
if cc.meta == nil {
return false
}
var sa *streamAssignment
if as := cc.streams[account]; as != nil {
sa = as[stream]
}
if sa == nil {
return false
}
rg := sa.Group
if rg == nil {
return false
}
// Check if we are the leader of this raftGroup assigned to the stream.
ourID := cc.meta.ID()
for _, peer := range rg.Peers {
if peer == ourID {
if len(rg.Peers) == 1 || rg.node != nil && rg.node.Leader() {
return true
}
}
}
return false
}
// Read lock should be held.
func (cc *jetStreamCluster) isConsumerLeader(account, stream, consumer string) bool {
// Non-clustered mode always return true.
if cc == nil {
return true
}
if cc.meta == nil {
return false
}
var sa *streamAssignment
if as := cc.streams[account]; as != nil {
sa = as[stream]
}
if sa == nil {
return false
}
// Check if we are the leader of this raftGroup assigned to this consumer.
ca := sa.consumers[consumer]
if ca == nil {
return false
}
rg := ca.Group
ourID := cc.meta.ID()
for _, peer := range rg.Peers {
if peer == ourID {
if len(rg.Peers) == 1 || (rg.node != nil && rg.node.Leader()) {
return true
}
}
}
return false
}
func (js *jetStream) monitorCluster() {
s, n := js.server(), js.getMetaGroup()
qch, lch, aq := n.QuitC(), n.LeadChangeC(), n.ApplyQ()
defer s.grWG.Done()
s.Debugf("Starting metadata monitor")
defer s.Debugf("Exiting metadata monitor")
const compactInterval = 2 * time.Minute
t := time.NewTicker(compactInterval)
defer t.Stop()
// Used to check cold boot cluster when possibly in mixed mode.
const leaderCheckInterval = time.Second
lt := time.NewTicker(leaderCheckInterval)
defer lt.Stop()
var (
isLeader bool
lastSnap []byte
lastSnapTime time.Time
isRecovering bool
beenLeader bool
)
// Set to true to start.
isRecovering = true
// Snapshotting function.
doSnapshot := func() {
// Suppress during recovery.
if isRecovering {
return
}
if snap := js.metaSnapshot(); !bytes.Equal(lastSnap, snap) {
if err := n.InstallSnapshot(snap); err == nil {
lastSnap = snap
lastSnapTime = time.Now()
}
}
}
for {
select {
case <-s.quitCh:
return
case <-qch:
return
case <-aq.ch:
ces := aq.pop()
for _, cei := range ces {
if cei == nil {
// Signals we have replayed all of our metadata.
isRecovering = false
s.Debugf("Recovered JetStream cluster metadata")
continue
}
ce := cei.(*CommittedEntry)
// FIXME(dlc) - Deal with errors.
if didSnap, didRemoval, err := js.applyMetaEntries(ce.Entries, isRecovering); err == nil {
_, nb := n.Applied(ce.Index)
if js.hasPeerEntries(ce.Entries) || didSnap || (didRemoval && time.Since(lastSnapTime) > 2*time.Second) {
// Since we received one make sure we have our own since we do not store
// our meta state outside of raft.
doSnapshot()
} else if lls := len(lastSnap); nb > uint64(lls*8) && lls > 0 {
doSnapshot()
}
}
}
aq.recycle(&ces)
case isLeader = <-lch:
// We want to make sure we are updated on statsz so ping the extended cluster.
if isLeader {
s.sendInternalMsgLocked(serverStatsPingReqSubj, _EMPTY_, nil, nil)
}
js.processLeaderChange(isLeader)
if isLeader && !beenLeader {
beenLeader = true
if n.NeedSnapshot() {
if err := n.InstallSnapshot(js.metaSnapshot()); err != nil {
s.Warnf("Error snapshotting JetStream cluster state: %v", err)
}
}
js.checkClusterSize()
}
case <-t.C:
doSnapshot()
// Periodically check the cluster size.
if n.Leader() {
js.checkClusterSize()
}
case <-lt.C:
s.Debugf("Checking JetStream cluster state")
// If we have a current leader or had one in the past we can cancel this here since the metaleader
// will be in charge of all peer state changes.
// For cold boot only.
if n.GroupLeader() != _EMPTY_ || n.HadPreviousLeader() {
lt.Stop()
continue
}
// If we are here we do not have a leader and we did not have a previous one, so cold start.
// Check to see if we can adjust our cluster size down iff we are in mixed mode and we have
// seen a total that is what our original estimate was.
cs := n.ClusterSize()
if js, total := s.trackedJetStreamServers(); js < total && total >= cs && js != cs {
s.Noticef("Adjusting JetStream expected peer set size to %d from original %d", js, cs)
n.AdjustBootClusterSize(js)
}
}
}
}
// This is called on first leader transition to double check the peers and cluster set size.
func (js *jetStream) checkClusterSize() {
s, n := js.server(), js.getMetaGroup()
if n == nil {
return
}
// We will check that we have a correct cluster set size by checking for any non-js servers
// which can happen in mixed mode.
ps := n.(*raft).currentPeerState()
if len(ps.knownPeers) >= ps.clusterSize {
return
}
// Grab our active peers.
peers := s.ActivePeers()
// If we have not registered all of our peers yet we can't do
// any adjustments based on a mixed mode. We will periodically check back.
if len(peers) < ps.clusterSize {
return
}
s.Debugf("Checking JetStream cluster size")
// If we are here our known set as the leader is not the same as the cluster size.
// Check to see if we have a mixed mode setup.
var totalJS int
for _, p := range peers {
if si, ok := s.nodeToInfo.Load(p); ok && si != nil {
if si.(nodeInfo).js {
totalJS++
}
}
}
// If we have less then our cluster size adjust that here. Can not do individual peer removals since
// they will not be in the tracked peers.
if totalJS < ps.clusterSize {
s.Debugf("Adjusting JetStream cluster size from %d to %d", ps.clusterSize, totalJS)
if err := n.AdjustClusterSize(totalJS); err != nil {
s.Warnf("Error adjusting JetStream cluster size: %v", err)
}
}
}
// Represents our stable meta state that we can write out.
type writeableStreamAssignment struct {
Client *ClientInfo `json:"client,omitempty"`
Created time.Time `json:"created"`
Config *StreamConfig `json:"stream"`
Group *raftGroup `json:"group"`
Sync string `json:"sync"`
Consumers []*consumerAssignment
}
func (js *jetStream) metaSnapshot() []byte {
var streams []writeableStreamAssignment
js.mu.RLock()
cc := js.cluster
for _, asa := range cc.streams {
for _, sa := range asa {
wsa := writeableStreamAssignment{
Client: sa.Client,
Created: sa.Created,
Config: sa.Config,
Group: sa.Group,
Sync: sa.Sync,
}
for _, ca := range sa.consumers {
wsa.Consumers = append(wsa.Consumers, ca)
}
streams = append(streams, wsa)
}
}
if len(streams) == 0 {
js.mu.RUnlock()
return nil
}
b, _ := json.Marshal(streams)
js.mu.RUnlock()
return s2.EncodeBetter(nil, b)
}
func (js *jetStream) applyMetaSnapshot(buf []byte, isRecovering bool) error {
if len(buf) == 0 {
return nil
}
jse, err := s2.Decode(nil, buf)
if err != nil {
return err
}
var wsas []writeableStreamAssignment
if err = json.Unmarshal(jse, &wsas); err != nil {
return err
}
// Build our new version here outside of js.
streams := make(map[string]map[string]*streamAssignment)
for _, wsa := range wsas {
as := streams[wsa.Client.serviceAccount()]
if as == nil {
as = make(map[string]*streamAssignment)
streams[wsa.Client.serviceAccount()] = as
}
sa := &streamAssignment{Client: wsa.Client, Created: wsa.Created, Config: wsa.Config, Group: wsa.Group, Sync: wsa.Sync}
if len(wsa.Consumers) > 0 {
sa.consumers = make(map[string]*consumerAssignment)
for _, ca := range wsa.Consumers {
sa.consumers[ca.Name] = ca