--- /dev/null
+package redis
+
+import (
+ "context"
+ "crypto/tls"
+ "errors"
+ "fmt"
+ "math"
+ "math/rand"
+ "net"
+ "sort"
+ "sync"
+ "sync/atomic"
+ "time"
+
+ "github.com/go-redis/redis/internal"
+ "github.com/go-redis/redis/internal/hashtag"
+ "github.com/go-redis/redis/internal/pool"
+ "github.com/go-redis/redis/internal/proto"
+ "github.com/go-redis/redis/internal/singleflight"
+)
+
+var errClusterNoNodes = fmt.Errorf("redis: cluster has no nodes")
+
+// ClusterOptions are used to configure a cluster client and should be
+// passed to NewClusterClient.
+type ClusterOptions struct {
+ // A seed list of host:port addresses of cluster nodes.
+ Addrs []string
+
+ // The maximum number of retries before giving up. Command is retried
+ // on network errors and MOVED/ASK redirects.
+ // Default is 8 retries.
+ MaxRedirects int
+
+ // Enables read-only commands on slave nodes.
+ ReadOnly bool
+ // Allows routing read-only commands to the closest master or slave node.
+ // It automatically enables ReadOnly.
+ RouteByLatency bool
+ // Allows routing read-only commands to the random master or slave node.
+ // It automatically enables ReadOnly.
+ RouteRandomly bool
+
+ // Optional function that returns cluster slots information.
+ // It is useful to manually create cluster of standalone Redis servers
+ // and load-balance read/write operations between master and slaves.
+ // It can use service like ZooKeeper to maintain configuration information
+ // and Cluster.ReloadState to manually trigger state reloading.
+ ClusterSlots func() ([]ClusterSlot, error)
+
+ // Following options are copied from Options struct.
+
+ OnConnect func(*Conn) error
+
+ MaxRetries int
+ MinRetryBackoff time.Duration
+ MaxRetryBackoff time.Duration
+ Password string
+
+ DialTimeout time.Duration
+ ReadTimeout time.Duration
+ WriteTimeout time.Duration
+
+ // PoolSize applies per cluster node and not for the whole cluster.
+ PoolSize int
+ PoolTimeout time.Duration
+ IdleTimeout time.Duration
+ IdleCheckFrequency time.Duration
+
+ TLSConfig *tls.Config
+}
+
+func (opt *ClusterOptions) init() {
+ if opt.MaxRedirects == -1 {
+ opt.MaxRedirects = 0
+ } else if opt.MaxRedirects == 0 {
+ opt.MaxRedirects = 8
+ }
+
+ if opt.RouteByLatency || opt.RouteRandomly {
+ opt.ReadOnly = true
+ }
+
+ switch opt.ReadTimeout {
+ case -1:
+ opt.ReadTimeout = 0
+ case 0:
+ opt.ReadTimeout = 3 * time.Second
+ }
+ switch opt.WriteTimeout {
+ case -1:
+ opt.WriteTimeout = 0
+ case 0:
+ opt.WriteTimeout = opt.ReadTimeout
+ }
+
+ switch opt.MinRetryBackoff {
+ case -1:
+ opt.MinRetryBackoff = 0
+ case 0:
+ opt.MinRetryBackoff = 8 * time.Millisecond
+ }
+ switch opt.MaxRetryBackoff {
+ case -1:
+ opt.MaxRetryBackoff = 0
+ case 0:
+ opt.MaxRetryBackoff = 512 * time.Millisecond
+ }
+}
+
+func (opt *ClusterOptions) clientOptions() *Options {
+ const disableIdleCheck = -1
+
+ return &Options{
+ OnConnect: opt.OnConnect,
+
+ MaxRetries: opt.MaxRetries,
+ MinRetryBackoff: opt.MinRetryBackoff,
+ MaxRetryBackoff: opt.MaxRetryBackoff,
+ Password: opt.Password,
+ readOnly: opt.ReadOnly,
+
+ DialTimeout: opt.DialTimeout,
+ ReadTimeout: opt.ReadTimeout,
+ WriteTimeout: opt.WriteTimeout,
+
+ PoolSize: opt.PoolSize,
+ PoolTimeout: opt.PoolTimeout,
+ IdleTimeout: opt.IdleTimeout,
+
+ IdleCheckFrequency: disableIdleCheck,
+
+ TLSConfig: opt.TLSConfig,
+ }
+}
+
+//------------------------------------------------------------------------------
+
+type clusterNode struct {
+ Client *Client
+
+ latency uint32 // atomic
+ generation uint32 // atomic
+ loading uint32 // atomic
+}
+
+func newClusterNode(clOpt *ClusterOptions, addr string) *clusterNode {
+ opt := clOpt.clientOptions()
+ opt.Addr = addr
+ node := clusterNode{
+ Client: NewClient(opt),
+ }
+
+ node.latency = math.MaxUint32
+ if clOpt.RouteByLatency {
+ go node.updateLatency()
+ }
+
+ return &node
+}
+
+func (n *clusterNode) String() string {
+ return n.Client.String()
+}
+
+func (n *clusterNode) Close() error {
+ return n.Client.Close()
+}
+
+func (n *clusterNode) updateLatency() {
+ const probes = 10
+
+ var latency uint32
+ for i := 0; i < probes; i++ {
+ start := time.Now()
+ n.Client.Ping()
+ probe := uint32(time.Since(start) / time.Microsecond)
+ latency = (latency + probe) / 2
+ }
+ atomic.StoreUint32(&n.latency, latency)
+}
+
+func (n *clusterNode) Latency() time.Duration {
+ latency := atomic.LoadUint32(&n.latency)
+ return time.Duration(latency) * time.Microsecond
+}
+
+func (n *clusterNode) MarkAsLoading() {
+ atomic.StoreUint32(&n.loading, uint32(time.Now().Unix()))
+}
+
+func (n *clusterNode) Loading() bool {
+ const minute = int64(time.Minute / time.Second)
+
+ loading := atomic.LoadUint32(&n.loading)
+ if loading == 0 {
+ return false
+ }
+ if time.Now().Unix()-int64(loading) < minute {
+ return true
+ }
+ atomic.StoreUint32(&n.loading, 0)
+ return false
+}
+
+func (n *clusterNode) Generation() uint32 {
+ return atomic.LoadUint32(&n.generation)
+}
+
+func (n *clusterNode) SetGeneration(gen uint32) {
+ for {
+ v := atomic.LoadUint32(&n.generation)
+ if gen < v || atomic.CompareAndSwapUint32(&n.generation, v, gen) {
+ break
+ }
+ }
+}
+
+//------------------------------------------------------------------------------
+
+type clusterNodes struct {
+ opt *ClusterOptions
+
+ mu sync.RWMutex
+ allAddrs []string
+ allNodes map[string]*clusterNode
+ clusterAddrs []string
+ closed bool
+
+ nodeCreateGroup singleflight.Group
+
+ _generation uint32 // atomic
+}
+
+func newClusterNodes(opt *ClusterOptions) *clusterNodes {
+ return &clusterNodes{
+ opt: opt,
+
+ allAddrs: opt.Addrs,
+ allNodes: make(map[string]*clusterNode),
+ }
+}
+
+func (c *clusterNodes) Close() error {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+
+ if c.closed {
+ return nil
+ }
+ c.closed = true
+
+ var firstErr error
+ for _, node := range c.allNodes {
+ if err := node.Client.Close(); err != nil && firstErr == nil {
+ firstErr = err
+ }
+ }
+
+ c.allNodes = nil
+ c.clusterAddrs = nil
+
+ return firstErr
+}
+
+func (c *clusterNodes) Addrs() ([]string, error) {
+ var addrs []string
+ c.mu.RLock()
+ closed := c.closed
+ if !closed {
+ if len(c.clusterAddrs) > 0 {
+ addrs = c.clusterAddrs
+ } else {
+ addrs = c.allAddrs
+ }
+ }
+ c.mu.RUnlock()
+
+ if closed {
+ return nil, pool.ErrClosed
+ }
+ if len(addrs) == 0 {
+ return nil, errClusterNoNodes
+ }
+ return addrs, nil
+}
+
+func (c *clusterNodes) NextGeneration() uint32 {
+ return atomic.AddUint32(&c._generation, 1)
+}
+
+// GC removes unused nodes.
+func (c *clusterNodes) GC(generation uint32) {
+ var collected []*clusterNode
+ c.mu.Lock()
+ for addr, node := range c.allNodes {
+ if node.Generation() >= generation {
+ continue
+ }
+
+ c.clusterAddrs = remove(c.clusterAddrs, addr)
+ delete(c.allNodes, addr)
+ collected = append(collected, node)
+ }
+ c.mu.Unlock()
+
+ for _, node := range collected {
+ _ = node.Client.Close()
+ }
+}
+
+func (c *clusterNodes) Get(addr string) (*clusterNode, error) {
+ var node *clusterNode
+ var err error
+ c.mu.RLock()
+ if c.closed {
+ err = pool.ErrClosed
+ } else {
+ node = c.allNodes[addr]
+ }
+ c.mu.RUnlock()
+ return node, err
+}
+
+func (c *clusterNodes) GetOrCreate(addr string) (*clusterNode, error) {
+ node, err := c.Get(addr)
+ if err != nil {
+ return nil, err
+ }
+ if node != nil {
+ return node, nil
+ }
+
+ v, err := c.nodeCreateGroup.Do(addr, func() (interface{}, error) {
+ node := newClusterNode(c.opt, addr)
+ return node, nil
+ })
+
+ c.mu.Lock()
+ defer c.mu.Unlock()
+
+ if c.closed {
+ return nil, pool.ErrClosed
+ }
+
+ node, ok := c.allNodes[addr]
+ if ok {
+ _ = v.(*clusterNode).Close()
+ return node, err
+ }
+ node = v.(*clusterNode)
+
+ c.allAddrs = appendIfNotExists(c.allAddrs, addr)
+ if err == nil {
+ c.clusterAddrs = append(c.clusterAddrs, addr)
+ }
+ c.allNodes[addr] = node
+
+ return node, err
+}
+
+func (c *clusterNodes) All() ([]*clusterNode, error) {
+ c.mu.RLock()
+ defer c.mu.RUnlock()
+
+ if c.closed {
+ return nil, pool.ErrClosed
+ }
+
+ cp := make([]*clusterNode, 0, len(c.allNodes))
+ for _, node := range c.allNodes {
+ cp = append(cp, node)
+ }
+ return cp, nil
+}
+
+func (c *clusterNodes) Random() (*clusterNode, error) {
+ addrs, err := c.Addrs()
+ if err != nil {
+ return nil, err
+ }
+
+ n := rand.Intn(len(addrs))
+ return c.GetOrCreate(addrs[n])
+}
+
+//------------------------------------------------------------------------------
+
+type clusterSlot struct {
+ start, end int
+ nodes []*clusterNode
+}
+
+type clusterSlotSlice []*clusterSlot
+
+func (p clusterSlotSlice) Len() int {
+ return len(p)
+}
+
+func (p clusterSlotSlice) Less(i, j int) bool {
+ return p[i].start < p[j].start
+}
+
+func (p clusterSlotSlice) Swap(i, j int) {
+ p[i], p[j] = p[j], p[i]
+}
+
+type clusterState struct {
+ nodes *clusterNodes
+ Masters []*clusterNode
+ Slaves []*clusterNode
+
+ slots []*clusterSlot
+
+ generation uint32
+ createdAt time.Time
+}
+
+func newClusterState(
+ nodes *clusterNodes, slots []ClusterSlot, origin string,
+) (*clusterState, error) {
+ c := clusterState{
+ nodes: nodes,
+
+ slots: make([]*clusterSlot, 0, len(slots)),
+
+ generation: nodes.NextGeneration(),
+ createdAt: time.Now(),
+ }
+
+ isLoopbackOrigin := isLoopbackAddr(origin)
+ for _, slot := range slots {
+ var nodes []*clusterNode
+ for i, slotNode := range slot.Nodes {
+ addr := slotNode.Addr
+ if !isLoopbackOrigin && useOriginAddr(origin, addr) {
+ addr = origin
+ }
+
+ node, err := c.nodes.GetOrCreate(addr)
+ if err != nil {
+ return nil, err
+ }
+
+ node.SetGeneration(c.generation)
+ nodes = append(nodes, node)
+
+ if i == 0 {
+ c.Masters = appendUniqueNode(c.Masters, node)
+ } else {
+ c.Slaves = appendUniqueNode(c.Slaves, node)
+ }
+ }
+
+ c.slots = append(c.slots, &clusterSlot{
+ start: slot.Start,
+ end: slot.End,
+ nodes: nodes,
+ })
+ }
+
+ sort.Sort(clusterSlotSlice(c.slots))
+
+ time.AfterFunc(time.Minute, func() {
+ nodes.GC(c.generation)
+ })
+
+ return &c, nil
+}
+
+func (c *clusterState) slotMasterNode(slot int) (*clusterNode, error) {
+ nodes := c.slotNodes(slot)
+ if len(nodes) > 0 {
+ return nodes[0], nil
+ }
+ return c.nodes.Random()
+}
+
+func (c *clusterState) slotSlaveNode(slot int) (*clusterNode, error) {
+ nodes := c.slotNodes(slot)
+ switch len(nodes) {
+ case 0:
+ return c.nodes.Random()
+ case 1:
+ return nodes[0], nil
+ case 2:
+ if slave := nodes[1]; !slave.Loading() {
+ return slave, nil
+ }
+ return nodes[0], nil
+ default:
+ var slave *clusterNode
+ for i := 0; i < 10; i++ {
+ n := rand.Intn(len(nodes)-1) + 1
+ slave = nodes[n]
+ if !slave.Loading() {
+ break
+ }
+ }
+ return slave, nil
+ }
+}
+
+func (c *clusterState) slotClosestNode(slot int) (*clusterNode, error) {
+ const threshold = time.Millisecond
+
+ nodes := c.slotNodes(slot)
+ if len(nodes) == 0 {
+ return c.nodes.Random()
+ }
+
+ var node *clusterNode
+ for _, n := range nodes {
+ if n.Loading() {
+ continue
+ }
+ if node == nil || node.Latency()-n.Latency() > threshold {
+ node = n
+ }
+ }
+ return node, nil
+}
+
+func (c *clusterState) slotRandomNode(slot int) *clusterNode {
+ nodes := c.slotNodes(slot)
+ n := rand.Intn(len(nodes))
+ return nodes[n]
+}
+
+func (c *clusterState) slotNodes(slot int) []*clusterNode {
+ i := sort.Search(len(c.slots), func(i int) bool {
+ return c.slots[i].end >= slot
+ })
+ if i >= len(c.slots) {
+ return nil
+ }
+ x := c.slots[i]
+ if slot >= x.start && slot <= x.end {
+ return x.nodes
+ }
+ return nil
+}
+
+func (c *clusterState) IsConsistent() bool {
+ if c.nodes.opt.ClusterSlots != nil {
+ return true
+ }
+ return len(c.Masters) <= len(c.Slaves)
+}
+
+//------------------------------------------------------------------------------
+
+type clusterStateHolder struct {
+ load func() (*clusterState, error)
+
+ state atomic.Value
+
+ firstErrMu sync.RWMutex
+ firstErr error
+
+ reloading uint32 // atomic
+}
+
+func newClusterStateHolder(fn func() (*clusterState, error)) *clusterStateHolder {
+ return &clusterStateHolder{
+ load: fn,
+ }
+}
+
+func (c *clusterStateHolder) Reload() (*clusterState, error) {
+ state, err := c.reload()
+ if err != nil {
+ return nil, err
+ }
+ if !state.IsConsistent() {
+ time.AfterFunc(time.Second, c.LazyReload)
+ }
+ return state, nil
+}
+
+func (c *clusterStateHolder) reload() (*clusterState, error) {
+ state, err := c.load()
+ if err != nil {
+ c.firstErrMu.Lock()
+ if c.firstErr == nil {
+ c.firstErr = err
+ }
+ c.firstErrMu.Unlock()
+ return nil, err
+ }
+ c.state.Store(state)
+ return state, nil
+}
+
+func (c *clusterStateHolder) LazyReload() {
+ if !atomic.CompareAndSwapUint32(&c.reloading, 0, 1) {
+ return
+ }
+ go func() {
+ defer atomic.StoreUint32(&c.reloading, 0)
+
+ for {
+ state, err := c.reload()
+ if err != nil {
+ return
+ }
+ time.Sleep(100 * time.Millisecond)
+ if state.IsConsistent() {
+ return
+ }
+ }
+ }()
+}
+
+func (c *clusterStateHolder) Get() (*clusterState, error) {
+ v := c.state.Load()
+ if v != nil {
+ state := v.(*clusterState)
+ if time.Since(state.createdAt) > time.Minute {
+ c.LazyReload()
+ }
+ return state, nil
+ }
+
+ c.firstErrMu.RLock()
+ err := c.firstErr
+ c.firstErrMu.RUnlock()
+ if err != nil {
+ return nil, err
+ }
+
+ return nil, errors.New("redis: cluster has no state")
+}
+
+func (c *clusterStateHolder) ReloadOrGet() (*clusterState, error) {
+ state, err := c.Reload()
+ if err == nil {
+ return state, nil
+ }
+ return c.Get()
+}
+
+//------------------------------------------------------------------------------
+
+// ClusterClient is a Redis Cluster client representing a pool of zero
+// or more underlying connections. It's safe for concurrent use by
+// multiple goroutines.
+type ClusterClient struct {
+ cmdable
+
+ ctx context.Context
+
+ opt *ClusterOptions
+ nodes *clusterNodes
+ state *clusterStateHolder
+ cmdsInfoCache *cmdsInfoCache
+
+ process func(Cmder) error
+ processPipeline func([]Cmder) error
+ processTxPipeline func([]Cmder) error
+}
+
+// NewClusterClient returns a Redis Cluster client as described in
+// http://redis.io/topics/cluster-spec.
+func NewClusterClient(opt *ClusterOptions) *ClusterClient {
+ opt.init()
+
+ c := &ClusterClient{
+ opt: opt,
+ nodes: newClusterNodes(opt),
+ }
+ c.state = newClusterStateHolder(c.loadState)
+ c.cmdsInfoCache = newCmdsInfoCache(c.cmdsInfo)
+
+ c.process = c.defaultProcess
+ c.processPipeline = c.defaultProcessPipeline
+ c.processTxPipeline = c.defaultProcessTxPipeline
+
+ c.init()
+
+ _, _ = c.state.Reload()
+ _, _ = c.cmdsInfoCache.Get()
+
+ if opt.IdleCheckFrequency > 0 {
+ go c.reaper(opt.IdleCheckFrequency)
+ }
+
+ return c
+}
+
+// ReloadState reloads cluster state. It calls ClusterSlots func
+// to get cluster slots information.
+func (c *ClusterClient) ReloadState() error {
+ _, err := c.state.Reload()
+ return err
+}
+
+func (c *ClusterClient) init() {
+ c.cmdable.setProcessor(c.Process)
+}
+
+func (c *ClusterClient) Context() context.Context {
+ if c.ctx != nil {
+ return c.ctx
+ }
+ return context.Background()
+}
+
+func (c *ClusterClient) WithContext(ctx context.Context) *ClusterClient {
+ if ctx == nil {
+ panic("nil context")
+ }
+ c2 := c.copy()
+ c2.ctx = ctx
+ return c2
+}
+
+func (c *ClusterClient) copy() *ClusterClient {
+ cp := *c
+ cp.init()
+ return &cp
+}
+
+// Options returns read-only Options that were used to create the client.
+func (c *ClusterClient) Options() *ClusterOptions {
+ return c.opt
+}
+
+func (c *ClusterClient) retryBackoff(attempt int) time.Duration {
+ return internal.RetryBackoff(attempt, c.opt.MinRetryBackoff, c.opt.MaxRetryBackoff)
+}
+
+func (c *ClusterClient) cmdsInfo() (map[string]*CommandInfo, error) {
+ addrs, err := c.nodes.Addrs()
+ if err != nil {
+ return nil, err
+ }
+
+ var firstErr error
+ for _, addr := range addrs {
+ node, err := c.nodes.Get(addr)
+ if err != nil {
+ return nil, err
+ }
+ if node == nil {
+ continue
+ }
+
+ info, err := node.Client.Command().Result()
+ if err == nil {
+ return info, nil
+ }
+ if firstErr == nil {
+ firstErr = err
+ }
+ }
+ return nil, firstErr
+}
+
+func (c *ClusterClient) cmdInfo(name string) *CommandInfo {
+ cmdsInfo, err := c.cmdsInfoCache.Get()
+ if err != nil {
+ return nil
+ }
+
+ info := cmdsInfo[name]
+ if info == nil {
+ internal.Logf("info for cmd=%s not found", name)
+ }
+ return info
+}
+
+func cmdSlot(cmd Cmder, pos int) int {
+ if pos == 0 {
+ return hashtag.RandomSlot()
+ }
+ firstKey := cmd.stringArg(pos)
+ return hashtag.Slot(firstKey)
+}
+
+func (c *ClusterClient) cmdSlot(cmd Cmder) int {
+ cmdInfo := c.cmdInfo(cmd.Name())
+ return cmdSlot(cmd, cmdFirstKeyPos(cmd, cmdInfo))
+}
+
+func (c *ClusterClient) cmdSlotAndNode(cmd Cmder) (int, *clusterNode, error) {
+ state, err := c.state.Get()
+ if err != nil {
+ return 0, nil, err
+ }
+
+ cmdInfo := c.cmdInfo(cmd.Name())
+ slot := cmdSlot(cmd, cmdFirstKeyPos(cmd, cmdInfo))
+
+ if cmdInfo != nil && cmdInfo.ReadOnly && c.opt.ReadOnly {
+ if c.opt.RouteByLatency {
+ node, err := state.slotClosestNode(slot)
+ return slot, node, err
+ }
+
+ if c.opt.RouteRandomly {
+ node := state.slotRandomNode(slot)
+ return slot, node, nil
+ }
+
+ node, err := state.slotSlaveNode(slot)
+ return slot, node, err
+ }
+
+ node, err := state.slotMasterNode(slot)
+ return slot, node, err
+}
+
+func (c *ClusterClient) slotMasterNode(slot int) (*clusterNode, error) {
+ state, err := c.state.Get()
+ if err != nil {
+ return nil, err
+ }
+
+ nodes := state.slotNodes(slot)
+ if len(nodes) > 0 {
+ return nodes[0], nil
+ }
+ return c.nodes.Random()
+}
+
+func (c *ClusterClient) Watch(fn func(*Tx) error, keys ...string) error {
+ if len(keys) == 0 {
+ return fmt.Errorf("redis: Watch requires at least one key")
+ }
+
+ slot := hashtag.Slot(keys[0])
+ for _, key := range keys[1:] {
+ if hashtag.Slot(key) != slot {
+ err := fmt.Errorf("redis: Watch requires all keys to be in the same slot")
+ return err
+ }
+ }
+
+ node, err := c.slotMasterNode(slot)
+ if err != nil {
+ return err
+ }
+
+ for attempt := 0; attempt <= c.opt.MaxRedirects; attempt++ {
+ if attempt > 0 {
+ time.Sleep(c.retryBackoff(attempt))
+ }
+
+ err = node.Client.Watch(fn, keys...)
+ if err == nil {
+ break
+ }
+
+ if internal.IsRetryableError(err, true) {
+ c.state.LazyReload()
+ continue
+ }
+
+ moved, ask, addr := internal.IsMovedError(err)
+ if moved || ask {
+ c.state.LazyReload()
+ node, err = c.nodes.GetOrCreate(addr)
+ if err != nil {
+ return err
+ }
+ continue
+ }
+
+ if err == pool.ErrClosed {
+ node, err = c.slotMasterNode(slot)
+ if err != nil {
+ return err
+ }
+ continue
+ }
+
+ return err
+ }
+
+ return err
+}
+
+// Close closes the cluster client, releasing any open resources.
+//
+// It is rare to Close a ClusterClient, as the ClusterClient is meant
+// to be long-lived and shared between many goroutines.
+func (c *ClusterClient) Close() error {
+ return c.nodes.Close()
+}
+
+func (c *ClusterClient) WrapProcess(
+ fn func(oldProcess func(Cmder) error) func(Cmder) error,
+) {
+ c.process = fn(c.process)
+}
+
+func (c *ClusterClient) Process(cmd Cmder) error {
+ return c.process(cmd)
+}
+
+func (c *ClusterClient) defaultProcess(cmd Cmder) error {
+ var node *clusterNode
+ var ask bool
+ for attempt := 0; attempt <= c.opt.MaxRedirects; attempt++ {
+ if attempt > 0 {
+ time.Sleep(c.retryBackoff(attempt))
+ }
+
+ if node == nil {
+ var err error
+ _, node, err = c.cmdSlotAndNode(cmd)
+ if err != nil {
+ cmd.setErr(err)
+ break
+ }
+ }
+
+ var err error
+ if ask {
+ pipe := node.Client.Pipeline()
+ _ = pipe.Process(NewCmd("ASKING"))
+ _ = pipe.Process(cmd)
+ _, err = pipe.Exec()
+ _ = pipe.Close()
+ ask = false
+ } else {
+ err = node.Client.Process(cmd)
+ }
+
+ // If there is no error - we are done.
+ if err == nil {
+ break
+ }
+
+ // If slave is loading - read from master.
+ if c.opt.ReadOnly && internal.IsLoadingError(err) {
+ node.MarkAsLoading()
+ continue
+ }
+
+ if internal.IsRetryableError(err, true) {
+ c.state.LazyReload()
+
+ // First retry the same node.
+ if attempt == 0 {
+ continue
+ }
+
+ // Second try random node.
+ node, err = c.nodes.Random()
+ if err != nil {
+ break
+ }
+ continue
+ }
+
+ var moved bool
+ var addr string
+ moved, ask, addr = internal.IsMovedError(err)
+ if moved || ask {
+ c.state.LazyReload()
+
+ node, err = c.nodes.GetOrCreate(addr)
+ if err != nil {
+ break
+ }
+ continue
+ }
+
+ if err == pool.ErrClosed {
+ node = nil
+ continue
+ }
+
+ break
+ }
+
+ return cmd.Err()
+}
+
+// ForEachMaster concurrently calls the fn on each master node in the cluster.
+// It returns the first error if any.
+func (c *ClusterClient) ForEachMaster(fn func(client *Client) error) error {
+ state, err := c.state.ReloadOrGet()
+ if err != nil {
+ return err
+ }
+
+ var wg sync.WaitGroup
+ errCh := make(chan error, 1)
+ for _, master := range state.Masters {
+ wg.Add(1)
+ go func(node *clusterNode) {
+ defer wg.Done()
+ err := fn(node.Client)
+ if err != nil {
+ select {
+ case errCh <- err:
+ default:
+ }
+ }
+ }(master)
+ }
+ wg.Wait()
+
+ select {
+ case err := <-errCh:
+ return err
+ default:
+ return nil
+ }
+}
+
+// ForEachSlave concurrently calls the fn on each slave node in the cluster.
+// It returns the first error if any.
+func (c *ClusterClient) ForEachSlave(fn func(client *Client) error) error {
+ state, err := c.state.ReloadOrGet()
+ if err != nil {
+ return err
+ }
+
+ var wg sync.WaitGroup
+ errCh := make(chan error, 1)
+ for _, slave := range state.Slaves {
+ wg.Add(1)
+ go func(node *clusterNode) {
+ defer wg.Done()
+ err := fn(node.Client)
+ if err != nil {
+ select {
+ case errCh <- err:
+ default:
+ }
+ }
+ }(slave)
+ }
+ wg.Wait()
+
+ select {
+ case err := <-errCh:
+ return err
+ default:
+ return nil
+ }
+}
+
+// ForEachNode concurrently calls the fn on each known node in the cluster.
+// It returns the first error if any.
+func (c *ClusterClient) ForEachNode(fn func(client *Client) error) error {
+ state, err := c.state.ReloadOrGet()
+ if err != nil {
+ return err
+ }
+
+ var wg sync.WaitGroup
+ errCh := make(chan error, 1)
+ worker := func(node *clusterNode) {
+ defer wg.Done()
+ err := fn(node.Client)
+ if err != nil {
+ select {
+ case errCh <- err:
+ default:
+ }
+ }
+ }
+
+ for _, node := range state.Masters {
+ wg.Add(1)
+ go worker(node)
+ }
+ for _, node := range state.Slaves {
+ wg.Add(1)
+ go worker(node)
+ }
+
+ wg.Wait()
+ select {
+ case err := <-errCh:
+ return err
+ default:
+ return nil
+ }
+}
+
+// PoolStats returns accumulated connection pool stats.
+func (c *ClusterClient) PoolStats() *PoolStats {
+ var acc PoolStats
+
+ state, _ := c.state.Get()
+ if state == nil {
+ return &acc
+ }
+
+ for _, node := range state.Masters {
+ s := node.Client.connPool.Stats()
+ acc.Hits += s.Hits
+ acc.Misses += s.Misses
+ acc.Timeouts += s.Timeouts
+
+ acc.TotalConns += s.TotalConns
+ acc.FreeConns += s.FreeConns
+ acc.StaleConns += s.StaleConns
+ }
+
+ for _, node := range state.Slaves {
+ s := node.Client.connPool.Stats()
+ acc.Hits += s.Hits
+ acc.Misses += s.Misses
+ acc.Timeouts += s.Timeouts
+
+ acc.TotalConns += s.TotalConns
+ acc.FreeConns += s.FreeConns
+ acc.StaleConns += s.StaleConns
+ }
+
+ return &acc
+}
+
+func (c *ClusterClient) loadState() (*clusterState, error) {
+ if c.opt.ClusterSlots != nil {
+ slots, err := c.opt.ClusterSlots()
+ if err != nil {
+ return nil, err
+ }
+ return newClusterState(c.nodes, slots, "")
+ }
+
+ addrs, err := c.nodes.Addrs()
+ if err != nil {
+ return nil, err
+ }
+
+ var firstErr error
+ for _, addr := range addrs {
+ node, err := c.nodes.GetOrCreate(addr)
+ if err != nil {
+ if firstErr == nil {
+ firstErr = err
+ }
+ continue
+ }
+
+ slots, err := node.Client.ClusterSlots().Result()
+ if err != nil {
+ if firstErr == nil {
+ firstErr = err
+ }
+ continue
+ }
+
+ return newClusterState(c.nodes, slots, node.Client.opt.Addr)
+ }
+
+ return nil, firstErr
+}
+
+// reaper closes idle connections to the cluster.
+func (c *ClusterClient) reaper(idleCheckFrequency time.Duration) {
+ ticker := time.NewTicker(idleCheckFrequency)
+ defer ticker.Stop()
+
+ for range ticker.C {
+ nodes, err := c.nodes.All()
+ if err != nil {
+ break
+ }
+
+ for _, node := range nodes {
+ _, err := node.Client.connPool.(*pool.ConnPool).ReapStaleConns()
+ if err != nil {
+ internal.Logf("ReapStaleConns failed: %s", err)
+ }
+ }
+ }
+}
+
+func (c *ClusterClient) Pipeline() Pipeliner {
+ pipe := Pipeline{
+ exec: c.processPipeline,
+ }
+ pipe.statefulCmdable.setProcessor(pipe.Process)
+ return &pipe
+}
+
+func (c *ClusterClient) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+ return c.Pipeline().Pipelined(fn)
+}
+
+func (c *ClusterClient) WrapProcessPipeline(
+ fn func(oldProcess func([]Cmder) error) func([]Cmder) error,
+) {
+ c.processPipeline = fn(c.processPipeline)
+}
+
+func (c *ClusterClient) defaultProcessPipeline(cmds []Cmder) error {
+ cmdsMap, err := c.mapCmdsByNode(cmds)
+ if err != nil {
+ setCmdsErr(cmds, err)
+ return err
+ }
+
+ for attempt := 0; attempt <= c.opt.MaxRedirects; attempt++ {
+ if attempt > 0 {
+ time.Sleep(c.retryBackoff(attempt))
+ }
+
+ failedCmds := make(map[*clusterNode][]Cmder)
+
+ for node, cmds := range cmdsMap {
+ cn, err := node.Client.getConn()
+ if err != nil {
+ if err == pool.ErrClosed {
+ c.remapCmds(cmds, failedCmds)
+ } else {
+ setCmdsErr(cmds, err)
+ }
+ continue
+ }
+
+ err = c.pipelineProcessCmds(node, cn, cmds, failedCmds)
+ if err == nil || internal.IsRedisError(err) {
+ node.Client.connPool.Put(cn)
+ } else {
+ node.Client.connPool.Remove(cn)
+ }
+ }
+
+ if len(failedCmds) == 0 {
+ break
+ }
+ cmdsMap = failedCmds
+ }
+
+ return firstCmdsErr(cmds)
+}
+
+func (c *ClusterClient) mapCmdsByNode(cmds []Cmder) (map[*clusterNode][]Cmder, error) {
+ state, err := c.state.Get()
+ if err != nil {
+ setCmdsErr(cmds, err)
+ return nil, err
+ }
+
+ cmdsMap := make(map[*clusterNode][]Cmder)
+ cmdsAreReadOnly := c.cmdsAreReadOnly(cmds)
+ for _, cmd := range cmds {
+ var node *clusterNode
+ var err error
+ if cmdsAreReadOnly {
+ _, node, err = c.cmdSlotAndNode(cmd)
+ } else {
+ slot := c.cmdSlot(cmd)
+ node, err = state.slotMasterNode(slot)
+ }
+ if err != nil {
+ return nil, err
+ }
+ cmdsMap[node] = append(cmdsMap[node], cmd)
+ }
+ return cmdsMap, nil
+}
+
+func (c *ClusterClient) cmdsAreReadOnly(cmds []Cmder) bool {
+ for _, cmd := range cmds {
+ cmdInfo := c.cmdInfo(cmd.Name())
+ if cmdInfo == nil || !cmdInfo.ReadOnly {
+ return false
+ }
+ }
+ return true
+}
+
+func (c *ClusterClient) remapCmds(cmds []Cmder, failedCmds map[*clusterNode][]Cmder) {
+ remappedCmds, err := c.mapCmdsByNode(cmds)
+ if err != nil {
+ setCmdsErr(cmds, err)
+ return
+ }
+
+ for node, cmds := range remappedCmds {
+ failedCmds[node] = cmds
+ }
+}
+
+func (c *ClusterClient) pipelineProcessCmds(
+ node *clusterNode, cn *pool.Conn, cmds []Cmder, failedCmds map[*clusterNode][]Cmder,
+) error {
+ cn.SetWriteTimeout(c.opt.WriteTimeout)
+
+ err := writeCmd(cn, cmds...)
+ if err != nil {
+ setCmdsErr(cmds, err)
+ failedCmds[node] = cmds
+ return err
+ }
+
+ // Set read timeout for all commands.
+ cn.SetReadTimeout(c.opt.ReadTimeout)
+
+ return c.pipelineReadCmds(cn, cmds, failedCmds)
+}
+
+func (c *ClusterClient) pipelineReadCmds(
+ cn *pool.Conn, cmds []Cmder, failedCmds map[*clusterNode][]Cmder,
+) error {
+ for _, cmd := range cmds {
+ err := cmd.readReply(cn)
+ if err == nil {
+ continue
+ }
+
+ if c.checkMovedErr(cmd, err, failedCmds) {
+ continue
+ }
+
+ if internal.IsRedisError(err) {
+ continue
+ }
+
+ return err
+ }
+ return nil
+}
+
+func (c *ClusterClient) checkMovedErr(
+ cmd Cmder, err error, failedCmds map[*clusterNode][]Cmder,
+) bool {
+ moved, ask, addr := internal.IsMovedError(err)
+
+ if moved {
+ c.state.LazyReload()
+
+ node, err := c.nodes.GetOrCreate(addr)
+ if err != nil {
+ return false
+ }
+
+ failedCmds[node] = append(failedCmds[node], cmd)
+ return true
+ }
+
+ if ask {
+ node, err := c.nodes.GetOrCreate(addr)
+ if err != nil {
+ return false
+ }
+
+ failedCmds[node] = append(failedCmds[node], NewCmd("ASKING"), cmd)
+ return true
+ }
+
+ return false
+}
+
+// TxPipeline acts like Pipeline, but wraps queued commands with MULTI/EXEC.
+func (c *ClusterClient) TxPipeline() Pipeliner {
+ pipe := Pipeline{
+ exec: c.processTxPipeline,
+ }
+ pipe.statefulCmdable.setProcessor(pipe.Process)
+ return &pipe
+}
+
+func (c *ClusterClient) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+ return c.TxPipeline().Pipelined(fn)
+}
+
+func (c *ClusterClient) defaultProcessTxPipeline(cmds []Cmder) error {
+ state, err := c.state.Get()
+ if err != nil {
+ return err
+ }
+
+ cmdsMap := c.mapCmdsBySlot(cmds)
+ for slot, cmds := range cmdsMap {
+ node, err := state.slotMasterNode(slot)
+ if err != nil {
+ setCmdsErr(cmds, err)
+ continue
+ }
+ cmdsMap := map[*clusterNode][]Cmder{node: cmds}
+
+ for attempt := 0; attempt <= c.opt.MaxRedirects; attempt++ {
+ if attempt > 0 {
+ time.Sleep(c.retryBackoff(attempt))
+ }
+
+ failedCmds := make(map[*clusterNode][]Cmder)
+
+ for node, cmds := range cmdsMap {
+ cn, err := node.Client.getConn()
+ if err != nil {
+ if err == pool.ErrClosed {
+ c.remapCmds(cmds, failedCmds)
+ } else {
+ setCmdsErr(cmds, err)
+ }
+ continue
+ }
+
+ err = c.txPipelineProcessCmds(node, cn, cmds, failedCmds)
+ if err == nil || internal.IsRedisError(err) {
+ node.Client.connPool.Put(cn)
+ } else {
+ node.Client.connPool.Remove(cn)
+ }
+ }
+
+ if len(failedCmds) == 0 {
+ break
+ }
+ cmdsMap = failedCmds
+ }
+ }
+
+ return firstCmdsErr(cmds)
+}
+
+func (c *ClusterClient) mapCmdsBySlot(cmds []Cmder) map[int][]Cmder {
+ cmdsMap := make(map[int][]Cmder)
+ for _, cmd := range cmds {
+ slot := c.cmdSlot(cmd)
+ cmdsMap[slot] = append(cmdsMap[slot], cmd)
+ }
+ return cmdsMap
+}
+
+func (c *ClusterClient) txPipelineProcessCmds(
+ node *clusterNode, cn *pool.Conn, cmds []Cmder, failedCmds map[*clusterNode][]Cmder,
+) error {
+ cn.SetWriteTimeout(c.opt.WriteTimeout)
+ if err := txPipelineWriteMulti(cn, cmds); err != nil {
+ setCmdsErr(cmds, err)
+ failedCmds[node] = cmds
+ return err
+ }
+
+ // Set read timeout for all commands.
+ cn.SetReadTimeout(c.opt.ReadTimeout)
+
+ if err := c.txPipelineReadQueued(cn, cmds, failedCmds); err != nil {
+ setCmdsErr(cmds, err)
+ return err
+ }
+
+ return pipelineReadCmds(cn, cmds)
+}
+
+func (c *ClusterClient) txPipelineReadQueued(
+ cn *pool.Conn, cmds []Cmder, failedCmds map[*clusterNode][]Cmder,
+) error {
+ // Parse queued replies.
+ var statusCmd StatusCmd
+ if err := statusCmd.readReply(cn); err != nil {
+ return err
+ }
+
+ for _, cmd := range cmds {
+ err := statusCmd.readReply(cn)
+ if err == nil {
+ continue
+ }
+
+ if c.checkMovedErr(cmd, err, failedCmds) || internal.IsRedisError(err) {
+ continue
+ }
+
+ return err
+ }
+
+ // Parse number of replies.
+ line, err := cn.Rd.ReadLine()
+ if err != nil {
+ if err == Nil {
+ err = TxFailedErr
+ }
+ return err
+ }
+
+ switch line[0] {
+ case proto.ErrorReply:
+ err := proto.ParseErrorReply(line)
+ for _, cmd := range cmds {
+ if !c.checkMovedErr(cmd, err, failedCmds) {
+ break
+ }
+ }
+ return err
+ case proto.ArrayReply:
+ // ok
+ default:
+ err := fmt.Errorf("redis: expected '*', but got line %q", line)
+ return err
+ }
+
+ return nil
+}
+
+func (c *ClusterClient) pubSub(channels []string) *PubSub {
+ var node *clusterNode
+ pubsub := &PubSub{
+ opt: c.opt.clientOptions(),
+
+ newConn: func(channels []string) (*pool.Conn, error) {
+ if node == nil {
+ var slot int
+ if len(channels) > 0 {
+ slot = hashtag.Slot(channels[0])
+ } else {
+ slot = -1
+ }
+
+ masterNode, err := c.slotMasterNode(slot)
+ if err != nil {
+ return nil, err
+ }
+ node = masterNode
+ }
+ return node.Client.newConn()
+ },
+ closeConn: func(cn *pool.Conn) error {
+ return node.Client.connPool.CloseConn(cn)
+ },
+ }
+ pubsub.init()
+ return pubsub
+}
+
+// Subscribe subscribes the client to the specified channels.
+// Channels can be omitted to create empty subscription.
+func (c *ClusterClient) Subscribe(channels ...string) *PubSub {
+ pubsub := c.pubSub(channels)
+ if len(channels) > 0 {
+ _ = pubsub.Subscribe(channels...)
+ }
+ return pubsub
+}
+
+// PSubscribe subscribes the client to the given patterns.
+// Patterns can be omitted to create empty subscription.
+func (c *ClusterClient) PSubscribe(channels ...string) *PubSub {
+ pubsub := c.pubSub(channels)
+ if len(channels) > 0 {
+ _ = pubsub.PSubscribe(channels...)
+ }
+ return pubsub
+}
+
+func useOriginAddr(originAddr, nodeAddr string) bool {
+ nodeHost, nodePort, err := net.SplitHostPort(nodeAddr)
+ if err != nil {
+ return false
+ }
+
+ nodeIP := net.ParseIP(nodeHost)
+ if nodeIP == nil {
+ return false
+ }
+
+ if !nodeIP.IsLoopback() {
+ return false
+ }
+
+ _, originPort, err := net.SplitHostPort(originAddr)
+ if err != nil {
+ return false
+ }
+
+ return nodePort == originPort
+}
+
+func isLoopbackAddr(addr string) bool {
+ host, _, err := net.SplitHostPort(addr)
+ if err != nil {
+ return false
+ }
+
+ ip := net.ParseIP(host)
+ if ip == nil {
+ return false
+ }
+
+ return ip.IsLoopback()
+}
+
+func appendUniqueNode(nodes []*clusterNode, node *clusterNode) []*clusterNode {
+ for _, n := range nodes {
+ if n == node {
+ return nodes
+ }
+ }
+ return append(nodes, node)
+}
+
+func appendIfNotExists(ss []string, es ...string) []string {
+loop:
+ for _, e := range es {
+ for _, s := range ss {
+ if s == e {
+ continue loop
+ }
+ }
+ ss = append(ss, e)
+ }
+ return ss
+}
+
+func remove(ss []string, es ...string) []string {
+ if len(es) == 0 {
+ return ss[:0]
+ }
+ for _, e := range es {
+ for i, s := range ss {
+ if s == e {
+ ss = append(ss[:i], ss[i+1:]...)
+ break
+ }
+ }
+ }
+ return ss
+}
Code Review / barometer.git / blobdiff