fix: use slot node id to detect node re-configuration

Author: vmihailenco

cluster.go

@@ -170,17 +170,19 @@ func (opt *ClusterOptions) clientOptions() *Options {
 //------------------------------------------------------------------------------
 
 type clusterNode struct {
+	id     string
 	Client *Client
 
 	latency    uint32 // atomic
 	generation uint32 // atomic
 	failing    uint32 // atomic
 }
 
-func newClusterNode(clOpt *ClusterOptions, addr string) *clusterNode {
+func newClusterNode(clOpt *ClusterOptions, id, addr string) *clusterNode {
 	opt := clOpt.clientOptions()
 	opt.Addr = addr
 	node := clusterNode{
+		id:     id,
 		Client: clOpt.NewClient(opt),
 	}
 
@@ -352,12 +354,16 @@ func (c *clusterNodes) GC(generation uint32) {
 	}
 }
 
-func (c *clusterNodes) Get(addr string) (*clusterNode, error) {
+func (c *clusterNodes) GetOrCreate(addr string) (*clusterNode, error) {
+	return c.GetOrCreateWithID(addr, "")
+}
+
+func (c *clusterNodes) GetOrCreateWithID(addr, id string) (*clusterNode, error) {
 	node, err := c.get(addr)
 	if err != nil {
 		return nil, err
 	}
-	if node != nil {
+	if node != nil && (id == "" || node.id == id) {
 		return node, nil
 	}
 
@@ -370,10 +376,13 @@ func (c *clusterNodes) Get(addr string) (*clusterNode, error) {
 
 	node, ok := c.nodes[addr]
 	if ok {
-		return node, nil
+		if id == "" || node.id == id {
+			return node, nil
+		}
+		delete(c.nodes, addr)
 	}
 
-	node = newClusterNode(c.opt, addr)
+	node = newClusterNode(c.opt, id, addr)
 
 	c.addrs = appendIfNotExists(c.addrs, addr)
 	c.nodes[addr] = node
@@ -416,7 +425,7 @@ func (c *clusterNodes) Random() (*clusterNode, error) {
 	}
 
 	n := rand.Intn(len(addrs))
-	return c.Get(addrs[n])
+	return c.GetOrCreate(addrs[n])
 }
 
 //------------------------------------------------------------------------------
@@ -474,7 +483,7 @@ func newClusterState(
 				addr = replaceLoopbackHost(addr, originHost)
 			}
 
-			node, err := c.nodes.Get(addr)
+			node, err := c.nodes.GetOrCreateWithID(addr, slotNode.ID)
 			if err != nil {
 				return nil, err
 			}
@@ -824,8 +833,10 @@ func (c *ClusterClient) process(ctx context.Context, cmd Cmder) error {
 		var addr string
 		moved, ask, addr = isMovedError(lastErr)
 		if moved || ask {
+			c.state.LazyReload()
+
 			var err error
-			node, err = c.nodes.Get(addr)
+			node, err = c.nodes.GetOrCreate(addr)
 			if err != nil {
 				return err
 			}
@@ -1022,7 +1033,7 @@ func (c *ClusterClient) loadState(ctx context.Context) (*clusterState, error) {
 	for _, idx := range rand.Perm(len(addrs)) {
 		addr := addrs[idx]
 
-		node, err := c.nodes.Get(addr)
+		node, err := c.nodes.GetOrCreate(addr)
 		if err != nil {
 			if firstErr == nil {
 				firstErr = err
@@ -1236,7 +1247,7 @@ func (c *ClusterClient) checkMovedErr(
 		return false
 	}
 
-	node, err := c.nodes.Get(addr)
+	node, err := c.nodes.GetOrCreate(addr)
 	if err != nil {
 		return false
 	}
@@ -1422,7 +1433,7 @@ func (c *ClusterClient) cmdsMoved(
 	addr string,
 	failedCmds *cmdsMap,
 ) error {
-	node, err := c.nodes.Get(addr)
+	node, err := c.nodes.GetOrCreate(addr)
 	if err != nil {
 		return err
 	}
@@ -1477,7 +1488,7 @@ func (c *ClusterClient) Watch(ctx context.Context, fn func(*Tx) error, keys ...s
 
 		moved, ask, addr := isMovedError(err)
 		if moved || ask {
-			node, err = c.nodes.Get(addr)
+			node, err = c.nodes.GetOrCreate(addr)
 			if err != nil {
 				return err
 			}
@@ -1589,7 +1600,7 @@ func (c *ClusterClient) cmdsInfo(ctx context.Context) (map[string]*CommandInfo,
 	for _, idx := range perm {
 		addr := addrs[idx]
 
-		node, err := c.nodes.Get(addr)
+		node, err := c.nodes.GetOrCreate(addr)
 		if err != nil {
 			if firstErr == nil {
 				firstErr = err