feat: add OpenTelemetry metrics instrumentation

CHANGELOG.md

@@ -1,70 +1,34 @@
-# [9.0.0-beta.2](https://github.com/go-redis/redis/compare/v9.0.0-beta.1...v9.0.0-beta.2) (2022-07-28)
-
-
-### Bug Fixes
-
-* [#2114](https://github.com/go-redis/redis/issues/2114) for redis-server not support Hello ([b6d2a92](https://github.com/go-redis/redis/commit/b6d2a925297e3e516eb5c76c114c1c9fcd5b68c5))
-* additional node failures in clustered pipelined reads ([03376a5](https://github.com/go-redis/redis/commit/03376a5d9c7dfd7197b14ce13b24a0431a07a663))
-* disregard failed pings in updateLatency() for cluster nodes ([64f972f](https://github.com/go-redis/redis/commit/64f972fbeae401e52a2c066a0e1c922af617e15c))
-* don't panic when test cannot start ([9e16c79](https://github.com/go-redis/redis/commit/9e16c79951e7769621b7320f1ecdf04baf539b82))
-* handle panic in ringShards Hash function when Ring got closed ([a80b84f](https://github.com/go-redis/redis/commit/a80b84f01f9fc0d3e6f08445ba21f7e07880775e)), closes [#2126](https://github.com/go-redis/redis/issues/2126)
-* ignore Nil error when reading EntriesRead ([89d6dfe](https://github.com/go-redis/redis/commit/89d6dfe09a88321d445858c1c5b24d2757b95a3e))
-* log errors from cmdsInfoCache ([fa4d1ea](https://github.com/go-redis/redis/commit/fa4d1ea8398cd729ad5cbaaff88e4b8805393945))
-* provide a signal channel to end heartbeat goroutine ([f032c12](https://github.com/go-redis/redis/commit/f032c126db3e2c1a239ce1790b0ab81994df75cf))
-* remove conn reaper from the pool and uptrace option names ([f6a8adc](https://github.com/go-redis/redis/commit/f6a8adc50cdaec30527f50d06468f9176ee674fe))
-* replace heartbeat signal channel with context.WithCancel ([20d0ca2](https://github.com/go-redis/redis/commit/20d0ca235efff48ad48cc05b98790b825d4ba979))
-
-
-
-# [9.0.0-beta.1](https://github.com/go-redis/redis/compare/v8.11.5...v9.0.0-beta.1) (2022-06-04)
-
-### Bug Fixes
-
-- **#1943:** xInfoConsumer.Idle should be time.Duration instead of int64
-  ([#2052](https://github.com/go-redis/redis/issues/2052))
-  ([997ab5e](https://github.com/go-redis/redis/commit/997ab5e7e3ddf53837917013a4babbded73e944f)),
-  closes [#1943](https://github.com/go-redis/redis/issues/1943)
-- add XInfoConsumers test
-  ([6f1a1ac](https://github.com/go-redis/redis/commit/6f1a1ac284ea3f683eeb3b06a59969e8424b6376))
-- fix tests
-  ([3a722be](https://github.com/go-redis/redis/commit/3a722be81180e4d2a9cf0a29dc9a1ee1421f5859))
-- remove test(XInfoConsumer.idle), not a stable return value when tested.
-  ([f5fbb36](https://github.com/go-redis/redis/commit/f5fbb367e7d9dfd7f391fc535a7387002232fa8a))
-- update ChannelWithSubscriptions to accept options
-  ([c98c5f0](https://github.com/go-redis/redis/commit/c98c5f0eebf8d254307183c2ce702a48256b718d))
-- update COMMAND parser for Redis 7
-  ([b0bb514](https://github.com/go-redis/redis/commit/b0bb514059249e01ed7328c9094e5b8a439dfb12))
-- use redis over ssh channel([#2057](https://github.com/go-redis/redis/issues/2057))
-  ([#2060](https://github.com/go-redis/redis/issues/2060))
-  ([3961b95](https://github.com/go-redis/redis/commit/3961b9577f622a3079fe74f8fc8da12ba67a77ff))
-
-### Features
-
-- add ClientUnpause
-  ([91171f5](https://github.com/go-redis/redis/commit/91171f5e19a261dc4cfbf8706626d461b6ba03e4))
-- add NewXPendingResult for unit testing XPending
-  ([#2066](https://github.com/go-redis/redis/issues/2066))
-  ([b7fd09e](https://github.com/go-redis/redis/commit/b7fd09e59479bc6ed5b3b13c4645a3620fd448a3))
-- add WriteArg and Scan net.IP([#2062](https://github.com/go-redis/redis/issues/2062))
-  ([7d5167e](https://github.com/go-redis/redis/commit/7d5167e8624ac1515e146ed183becb97dadb3d1a))
-- **pool:** add check for badConnection
-  ([a8a7665](https://github.com/go-redis/redis/commit/a8a7665ddf8cc657c5226b1826a8ee83dab4b8c1)),
-  closes [#2053](https://github.com/go-redis/redis/issues/2053)
-- provide a username and password callback method, so that the plaintext username and password will
-  not be stored in the memory, and the username and password will only be generated once when the
-  CredentialsProvider is called. After the method is executed, the username and password strings on
-  the stack will be released. ([#2097](https://github.com/go-redis/redis/issues/2097))
-  ([56a3dbc](https://github.com/go-redis/redis/commit/56a3dbc7b656525eb88e0735e239d56e04a23bee))
-- upgrade to Redis 7
-  ([d09c27e](https://github.com/go-redis/redis/commit/d09c27e6046129fd27b1d275e5a13a477bd7f778))
-
 ## v9 UNRELEASED
 
+### Added
+
 - Added support for [RESP3](https://github.com/antirez/RESP3/blob/master/spec.md) protocol.
-- Removed `Pipeline.Close` since there is no real need to explicitly manage pipeline resources.
+  Contributed by @monkey92t who has done a lot of work recently.
-  `Pipeline.Discard` is still available if you want to reset commands for some reason.
+- Added `ContextTimeoutEnabled` option that controls whether the client respects context timeouts
-- Replaced `*redis.Z` with `redis.Z` since it is small enough to be passed as value.
+  and deadlines. See
-- Renamed `MaxConnAge` to `ConnMaxLifetime`.
+  [Redis Timeouts](https://redis.uptrace.dev/guide/go-redis-debugging.html#timeouts) for details.
-- Renamed `IdleTimeout` to `ConnMaxIdleTime`.
+- Added `ParseClusterURL` to parse URLs into `ClusterOptions`, for example,
+  `redis://user:password@localhost:6789?dial_timeout=3&read_timeout=6s&addr=localhost:6790&addr=localhost:6791`.
+- Added metrics instrumentation using `redisotel.IstrumentMetrics`. See
+  [documentation](https://redis.uptrace.dev/guide/go-redis-monitoring.html)
+
+### Changed
+
+- Reworked hook interface and added `DialHook`.
+- Replaced `redisotel.NewTracingHook` with `redisotel.InstrumentTracing`. See
+  [example](example/otel) and
+  [documentation](https://redis.uptrace.dev/guide/go-redis-monitoring.html).
+- Replaced `*redis.Z` with `redis.Z` since it is small enough to be passed as value without making
+  an allocation.
+- Renamed the option `MaxConnAge` to `ConnMaxLifetime`.
+- Renamed the option `IdleTimeout` to `ConnMaxIdleTime`.
 - Removed connection reaper in favor of `MaxIdleConns`.
-- Removed `WithContext`.
+- Removed `WithContext` since `context.Context` can be passed directly as an arg.
+- Removed `Pipeline.Close` since there is no real need to explicitly manage pipeline resources and
+  it can be safely reused via `sync.Pool` etc. `Pipeline.Discard` is still available if you want to
+  reset commands for some reason.
+
+### Fixed
+
+- Improved and fixed pipeline retries.
+- As usual, added more commands and fixed some bugs.

cluster.go

@@ -71,11 +71,8 @@ type ClusterOptions struct {
 	WriteTimeout          time.Duration
 	ContextTimeoutEnabled bool
 
-	// PoolFIFO uses FIFO mode for each node connection pool GET/PUT (default LIFO).
 	PoolFIFO        bool
-
+	PoolSize        int // applies per cluster node and not for the whole cluster
-	// PoolSize applies per cluster node and not for the whole cluster.
-	PoolSize        int
 	PoolTimeout     time.Duration
 	MinIdleConns    int
 	MaxIdleConns    int
@@ -391,6 +388,7 @@ type clusterNodes struct {
 	nodes       map[string]*clusterNode
 	activeAddrs []string
 	closed      bool
+	onNewNode   []func(rdb *Client)
 
 	_generation uint32 // atomic
 }
@@ -426,6 +424,12 @@ func (c *clusterNodes) Close() error {
 	return firstErr
 }
 
+func (c *clusterNodes) OnNewNode(fn func(rdb *Client)) {
+	c.mu.Lock()
+	c.onNewNode = append(c.onNewNode, fn)
+	c.mu.Unlock()
+}
+
 func (c *clusterNodes) Addrs() ([]string, error) {
 	var addrs []string
 
@@ -503,6 +507,9 @@ func (c *clusterNodes) GetOrCreate(addr string) (*clusterNode, error) {
 	}
 
 	node = newClusterNode(c.opt, addr)
+	for _, fn := range c.onNewNode {
+		fn(node.Client)
+	}
 
 	c.addrs = appendIfNotExists(c.addrs, addr)
 	c.nodes[addr] = node
@@ -812,18 +819,14 @@ func (c *clusterStateHolder) ReloadOrGet(ctx context.Context) (*clusterState, er
 
 //------------------------------------------------------------------------------
 
-type clusterClient struct {
-	opt           *ClusterOptions
-	nodes         *clusterNodes
-	state         *clusterStateHolder //nolint:structcheck
-	cmdsInfoCache *cmdsInfoCache      //nolint:structcheck
-}
-
 // 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 {
-	*clusterClient
+	opt           *ClusterOptions
+	nodes         *clusterNodes
+	state         *clusterStateHolder
+	cmdsInfoCache *cmdsInfoCache
 	cmdable
 	hooks
 }
@@ -834,15 +837,18 @@ func NewClusterClient(opt *ClusterOptions) *ClusterClient {
 	opt.init()
 
 	c := &ClusterClient{
-		clusterClient: &clusterClient{
 		opt:   opt,
 		nodes: newClusterNodes(opt),
-		},
 	}
+
 	c.state = newClusterStateHolder(c.loadState)
 	c.cmdsInfoCache = newCmdsInfoCache(c.cmdsInfo)
 	c.cmdable = c.Process
 
+	c.hooks.process = c.process
+	c.hooks.processPipeline = c._processPipeline
+	c.hooks.processTxPipeline = c._processTxPipeline
+
 	return c
 }
 
@@ -873,13 +879,14 @@ func (c *ClusterClient) Do(ctx context.Context, args ...interface{}) *Cmd {
 }
 
 func (c *ClusterClient) Process(ctx context.Context, cmd Cmder) error {
-	return c.hooks.process(ctx, cmd, c.process)
+	err := c.hooks.process(ctx, cmd)
+	cmd.SetErr(err)
+	return err
 }
 
 func (c *ClusterClient) process(ctx context.Context, cmd Cmder) error {
 	cmdInfo := c.cmdInfo(ctx, cmd.Name())
 	slot := c.cmdSlot(ctx, cmd)
-
 	var node *clusterNode
 	var ask bool
 	var lastErr error
@@ -899,11 +906,12 @@ func (c *ClusterClient) process(ctx context.Context, cmd Cmder) error {
 		}
 
 		if ask {
+			ask = false
+
 			pipe := node.Client.Pipeline()
 			_ = pipe.Process(ctx, NewCmd(ctx, "asking"))
 			_ = pipe.Process(ctx, cmd)
 			_, lastErr = pipe.Exec(ctx)
-			ask = false
 		} else {
 			lastErr = node.Client.Process(ctx, cmd)
 		}
@@ -958,6 +966,10 @@ func (c *ClusterClient) process(ctx context.Context, cmd Cmder) error {
 	return lastErr
 }
 
+func (c *ClusterClient) OnNewNode(fn func(rdb *Client)) {
+	c.nodes.OnNewNode(fn)
+}
+
 // ForEachMaster concurrently calls the fn on each master node in the cluster.
 // It returns the first error if any.
 func (c *ClusterClient) ForEachMaster(
@@ -1165,7 +1177,7 @@ func (c *ClusterClient) loadState(ctx context.Context) (*clusterState, error) {
 
 func (c *ClusterClient) Pipeline() Pipeliner {
 	pipe := Pipeline{
-		exec: c.processPipeline,
+		exec: pipelineExecer(c.hooks.processPipeline),
 	}
 	pipe.init()
 	return &pipe
@@ -1175,10 +1187,6 @@ func (c *ClusterClient) Pipelined(ctx context.Context, fn func(Pipeliner) error)
 	return c.Pipeline().Pipelined(ctx, fn)
 }
 
-func (c *ClusterClient) processPipeline(ctx context.Context, cmds []Cmder) error {
-	return c.hooks.processPipeline(ctx, cmds, c._processPipeline)
-}
-
 func (c *ClusterClient) _processPipeline(ctx context.Context, cmds []Cmder) error {
 	cmdsMap := newCmdsMap()
 
@@ -1258,7 +1266,7 @@ func (c *ClusterClient) cmdsAreReadOnly(ctx context.Context, cmds []Cmder) bool
 func (c *ClusterClient) _processPipelineNode(
 	ctx context.Context, node *clusterNode, cmds []Cmder, failedCmds *cmdsMap,
 ) {
-	_ = node.Client.hooks.processPipeline(ctx, cmds, func(ctx context.Context, cmds []Cmder) error {
+	_ = node.Client.hooks.withProcessPipelineHook(ctx, cmds, func(ctx context.Context, cmds []Cmder) error {
 		return node.Client.withConn(ctx, func(ctx context.Context, cn *pool.Conn) error {
 			if err := cn.WithWriter(c.context(ctx), c.opt.WriteTimeout, func(wr *proto.Writer) error {
 				return writeCmds(wr, cmds)
@@ -1344,7 +1352,10 @@ func (c *ClusterClient) checkMovedErr(
 // TxPipeline acts like Pipeline, but wraps queued commands with MULTI/EXEC.
 func (c *ClusterClient) TxPipeline() Pipeliner {
 	pipe := Pipeline{
-		exec: c.processTxPipeline,
+		exec: func(ctx context.Context, cmds []Cmder) error {
+			cmds = wrapMultiExec(ctx, cmds)
+			return c.hooks.processTxPipeline(ctx, cmds)
+		},
 	}
 	pipe.init()
 	return &pipe
@@ -1354,10 +1365,6 @@ func (c *ClusterClient) TxPipelined(ctx context.Context, fn func(Pipeliner) erro
 	return c.TxPipeline().Pipelined(ctx, fn)
 }
 
-func (c *ClusterClient) processTxPipeline(ctx context.Context, cmds []Cmder) error {
-	return c.hooks.processTxPipeline(ctx, cmds, c._processTxPipeline)
-}
-
 func (c *ClusterClient) _processTxPipeline(ctx context.Context, cmds []Cmder) error {
 	// Trim multi .. exec.
 	cmds = cmds[1 : len(cmds)-1]
@@ -1419,8 +1426,8 @@ func (c *ClusterClient) mapCmdsBySlot(ctx context.Context, cmds []Cmder) map[int
 func (c *ClusterClient) _processTxPipelineNode(
 	ctx context.Context, node *clusterNode, cmds []Cmder, failedCmds *cmdsMap,
 ) {
-	_ = node.Client.hooks.processTxPipeline(
+	cmds = wrapMultiExec(ctx, cmds)
-		ctx, cmds, func(ctx context.Context, cmds []Cmder) error {
+	_ = node.Client.hooks.withProcessPipelineHook(ctx, cmds, func(ctx context.Context, cmds []Cmder) error {
 		return node.Client.withConn(ctx, func(ctx context.Context, cn *pool.Conn) error {
 			if err := cn.WithWriter(c.context(ctx), c.opt.WriteTimeout, func(wr *proto.Writer) error {
 				return writeCmds(wr, cmds)
@@ -1742,7 +1749,7 @@ func (c *ClusterClient) cmdNode(
 	return state.slotMasterNode(slot)
 }
 
-func (c *clusterClient) slotReadOnlyNode(state *clusterState, slot int) (*clusterNode, error) {
+func (c *ClusterClient) slotReadOnlyNode(state *clusterState, slot int) (*clusterNode, error) {
 	if c.opt.RouteByLatency {
 		return state.slotClosestNode(slot)
 	}

cluster_commands.go

@@ -8,7 +8,7 @@ import (
 
 func (c *ClusterClient) DBSize(ctx context.Context) *IntCmd {
 	cmd := NewIntCmd(ctx, "dbsize")
-	_ = c.hooks.process(ctx, cmd, func(ctx context.Context, _ Cmder) error {
+	_ = c.hooks.withProcessHook(ctx, cmd, func(ctx context.Context, _ Cmder) error {
 		var size int64
 		err := c.ForEachMaster(ctx, func(ctx context.Context, master *Client) error {
 			n, err := master.DBSize(ctx).Result()
@@ -30,7 +30,7 @@ func (c *ClusterClient) DBSize(ctx context.Context) *IntCmd {
 
 func (c *ClusterClient) ScriptLoad(ctx context.Context, script string) *StringCmd {
 	cmd := NewStringCmd(ctx, "script", "load", script)
-	_ = c.hooks.process(ctx, cmd, func(ctx context.Context, _ Cmder) error {
+	_ = c.hooks.withProcessHook(ctx, cmd, func(ctx context.Context, _ Cmder) error {
 		mu := &sync.Mutex{}
 		err := c.ForEachShard(ctx, func(ctx context.Context, shard *Client) error {
 			val, err := shard.ScriptLoad(ctx, script).Result()
@@ -56,7 +56,7 @@ func (c *ClusterClient) ScriptLoad(ctx context.Context, script string) *StringCm
 
 func (c *ClusterClient) ScriptFlush(ctx context.Context) *StatusCmd {
 	cmd := NewStatusCmd(ctx, "script", "flush")
-	_ = c.hooks.process(ctx, cmd, func(ctx context.Context, _ Cmder) error {
+	_ = c.hooks.withProcessHook(ctx, cmd, func(ctx context.Context, _ Cmder) error {
 		err := c.ForEachShard(ctx, func(ctx context.Context, shard *Client) error {
 			return shard.ScriptFlush(ctx).Err()
 		})
@@ -82,8 +82,8 @@ func (c *ClusterClient) ScriptExists(ctx context.Context, hashes ...string) *Boo
 		result[i] = true
 	}
 
-	_ = c.hooks.process(ctx, cmd, func(ctx context.Context, _ Cmder) error {
+	_ = c.hooks.withProcessHook(ctx, cmd, func(ctx context.Context, _ Cmder) error {
-		mu := &sync.Mutex{}
+		var mu sync.Mutex
 		err := c.ForEachShard(ctx, func(ctx context.Context, shard *Client) error {
 			val, err := shard.ScriptExists(ctx, hashes...).Result()
 			if err != nil {

cluster_test.go

@@ -755,6 +755,9 @@ var _ = Describe("ClusterClient", func() {
 		})
 
 		It("supports Process hook", func() {
+			testCtx, cancel := context.WithCancel(ctx)
+			defer cancel()
+
 			err := client.Ping(ctx).Err()
 			Expect(err).NotTo(HaveOccurred())
 
@@ -766,29 +769,47 @@ var _ = Describe("ClusterClient", func() {
 			var stack []string
 
 			clusterHook := &hook{
-				beforeProcess: func(ctx context.Context, cmd redis.Cmder) (context.Context, error) {
+				processHook: func(hook redis.ProcessHook) redis.ProcessHook {
+					return func(ctx context.Context, cmd redis.Cmder) error {
+						select {
+						case <-testCtx.Done():
+							return hook(ctx, cmd)
+						default:
+						}
+
 						Expect(cmd.String()).To(Equal("ping: "))
 						stack = append(stack, "cluster.BeforeProcess")
-					return ctx, nil
+
-				},
+						err := hook(ctx, cmd)
-				afterProcess: func(ctx context.Context, cmd redis.Cmder) error {
+
 						Expect(cmd.String()).To(Equal("ping: PONG"))
 						stack = append(stack, "cluster.AfterProcess")
-					return nil
+
+						return err
+					}
 				},
 			}
 			client.AddHook(clusterHook)
 
 			nodeHook := &hook{
-				beforeProcess: func(ctx context.Context, cmd redis.Cmder) (context.Context, error) {
+				processHook: func(hook redis.ProcessHook) redis.ProcessHook {
+					return func(ctx context.Context, cmd redis.Cmder) error {
+						select {
+						case <-testCtx.Done():
+							return hook(ctx, cmd)
+						default:
+						}
+
 						Expect(cmd.String()).To(Equal("ping: "))
 						stack = append(stack, "shard.BeforeProcess")
-					return ctx, nil
+
-				},
+						err := hook(ctx, cmd)
-				afterProcess: func(ctx context.Context, cmd redis.Cmder) error {
+
 						Expect(cmd.String()).To(Equal("ping: PONG"))
 						stack = append(stack, "shard.AfterProcess")
-					return nil
+
+						return err
+					}
 				},
 			}
 
@@ -805,11 +826,6 @@ var _ = Describe("ClusterClient", func() {
 				"shard.AfterProcess",
 				"cluster.AfterProcess",
 			}))
-
-			clusterHook.beforeProcess = nil
-			clusterHook.afterProcess = nil
-			nodeHook.beforeProcess = nil
-			nodeHook.afterProcess = nil
 		})
 
 		It("supports Pipeline hook", func() {
@@ -824,33 +840,39 @@ var _ = Describe("ClusterClient", func() {
 			var stack []string
 
 			client.AddHook(&hook{
-				beforeProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+				processPipelineHook: func(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
+					return func(ctx context.Context, cmds []redis.Cmder) error {
 						Expect(cmds).To(HaveLen(1))
 						Expect(cmds[0].String()).To(Equal("ping: "))
 						stack = append(stack, "cluster.BeforeProcessPipeline")
-					return ctx, nil
+
-				},
+						err := hook(ctx, cmds)
-				afterProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) error {
+
 						Expect(cmds).To(HaveLen(1))
 						Expect(cmds[0].String()).To(Equal("ping: PONG"))
 						stack = append(stack, "cluster.AfterProcessPipeline")
-					return nil
+
+						return err
+					}
 				},
 			})
 
 			_ = client.ForEachShard(ctx, func(ctx context.Context, node *redis.Client) error {
 				node.AddHook(&hook{
-					beforeProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+					processPipelineHook: func(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
+						return func(ctx context.Context, cmds []redis.Cmder) error {
 							Expect(cmds).To(HaveLen(1))
 							Expect(cmds[0].String()).To(Equal("ping: "))
 							stack = append(stack, "shard.BeforeProcessPipeline")
-						return ctx, nil
+
-					},
+							err := hook(ctx, cmds)
-					afterProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) error {
+
 							Expect(cmds).To(HaveLen(1))
 							Expect(cmds[0].String()).To(Equal("ping: PONG"))
 							stack = append(stack, "shard.AfterProcessPipeline")
-						return nil
+
+							return err
+						}
 					},
 				})
 				return nil
@@ -881,33 +903,39 @@ var _ = Describe("ClusterClient", func() {
 			var stack []string
 
 			client.AddHook(&hook{
-				beforeProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+				processPipelineHook: func(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
+					return func(ctx context.Context, cmds []redis.Cmder) error {
 						Expect(cmds).To(HaveLen(3))
 						Expect(cmds[1].String()).To(Equal("ping: "))
 						stack = append(stack, "cluster.BeforeProcessPipeline")
-					return ctx, nil
+
-				},
+						err := hook(ctx, cmds)
-				afterProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) error {
+
 						Expect(cmds).To(HaveLen(3))
 						Expect(cmds[1].String()).To(Equal("ping: PONG"))
 						stack = append(stack, "cluster.AfterProcessPipeline")
-					return nil
+
+						return err
+					}
 				},
 			})
 
 			_ = client.ForEachShard(ctx, func(ctx context.Context, node *redis.Client) error {
 				node.AddHook(&hook{
-					beforeProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+					processPipelineHook: func(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
+						return func(ctx context.Context, cmds []redis.Cmder) error {
 							Expect(cmds).To(HaveLen(3))
 							Expect(cmds[1].String()).To(Equal("ping: "))
 							stack = append(stack, "shard.BeforeProcessPipeline")
-						return ctx, nil
+
-					},
+							err := hook(ctx, cmds)
-					afterProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) error {
+
 							Expect(cmds).To(HaveLen(3))
 							Expect(cmds[1].String()).To(Equal("ping: PONG"))
 							stack = append(stack, "shard.AfterProcessPipeline")
-						return nil
+
+							return err
+						}
 					},
 				})
 				return nil

example/otel/README.md

@@ -1,7 +1,7 @@
 # Example for go-redis OpenTelemetry instrumentation
 
 See
-[Redis Monitoring Performance and Errors](https://redis.uptrace.dev/guide/redis-performance-monitoring.html)
+[Monitoring Go Redis Performance and Errors](https://redis.uptrace.dev/guide/go-redis-monitoring.html)
 for details.
 
 This example requires Redis Server on port `:6379`. You can start Redis Server using Docker:
@@ -18,19 +18,23 @@ You can run this example with different OpenTelemetry exporters by providing env
 go run .
 ```
 
+[Uptrace](https://github.com/uptrace/uptrace) exporter:
+
+```shell
+UPTRACE_DSN="https://<token>@uptrace.dev/<project_id>" go run .
+```
+
 **Jaeger** exporter:
 
 ```shell
 OTEL_EXPORTER_JAEGER_ENDPOINT=http://localhost:14268/api/traces go run .
 ```
 
-**Uptrace** exporter:
+To instrument Redis Cluster client, see
-
+[go-redis-cluster](https://github.com/uptrace/opentelemetry-go-extra/tree/main/example/go-redis-cluster)
-```shell
+example.
-UPTRACE_DSN="https://<token>@uptrace.dev/<project_id>" go run .
-```
 
 ## Links
 
-- [Find instrumentations](https://opentelemetry.uptrace.dev/instrumentations/?lang=go)
+- [OpenTelemetry Go instrumentations](https://uptrace.dev/opentelemetry/instrumentations/?lang=go)
-- [OpenTelemetry Tracing API](https://opentelemetry.uptrace.dev/guide/go-tracing.html)
+- [OpenTelemetry Go Tracing API](https://uptrace.dev/opentelemetry/go-tracing.html)

example/otel/go.mod

@@ -12,7 +12,7 @@ require (
 	github.com/go-redis/redis/extra/redisotel/v9 v9.0.0-beta.2
 	github.com/go-redis/redis/v9 v9.0.0-beta.2
 	github.com/uptrace/opentelemetry-go-extra/otelplay v0.1.15
-	go.opentelemetry.io/otel v1.8.0
+	go.opentelemetry.io/otel v1.10.0
 	golang.org/x/net v0.0.0-20220728030405-41545e8bf201 // indirect
 	google.golang.org/genproto v0.0.0-20220725144611-272f38e5d71b // indirect
 )

example/otel/go.sum

@@ -218,14 +218,17 @@ github.com/onsi/ginkgo v1.16.4/go.mod h1:dX+/inL/fNMqNlz0e9LfyB9TswhZpCVdJM/Z6Vv
 github.com/onsi/ginkgo v1.16.5 h1:8xi0RTUf59SOSfEtZMvwTvXYMzG4gV23XVHOZiXNtnE=
 github.com/onsi/ginkgo v1.16.5/go.mod h1:+E8gABHa3K6zRBolWtd+ROzc/U5bkGt0FwiG042wbpU=
 github.com/onsi/ginkgo/v2 v2.1.3/go.mod h1:vw5CSIxN1JObi/U8gcbwft7ZxR2dgaR70JSE3/PpL4c=
-github.com/onsi/ginkgo/v2 v2.1.4 h1:GNapqRSid3zijZ9H77KrgVG4/8KqiyRsxcSxe+7ApXY=
 github.com/onsi/ginkgo/v2 v2.1.4/go.mod h1:um6tUpWM/cxCK3/FK8BXqEiUMUwRgSM4JXG47RKZmLU=
+github.com/onsi/ginkgo/v2 v2.1.6 h1:Fx2POJZfKRQcM1pH49qSZiYeu319wji004qX+GDovrU=
+github.com/onsi/ginkgo/v2 v2.1.6/go.mod h1:MEH45j8TBi6u9BMogfbp0stKC5cdGjumZj5Y7AG4VIk=
 github.com/onsi/gomega v1.7.1/go.mod h1:XdKZgCCFLUoM/7CFJVPcG8C1xQ1AJ0vpAezJrB7JYyY=
 github.com/onsi/gomega v1.10.1/go.mod h1:iN09h71vgCQne3DLsj+A5owkum+a2tYe+TOCB1ybHNo=
 github.com/onsi/gomega v1.17.0/go.mod h1:HnhC7FXeEQY45zxNK3PPoIUhzk/80Xly9PcubAlGdZY=
 github.com/onsi/gomega v1.19.0/go.mod h1:LY+I3pBVzYsTBU1AnDwOSxaYi9WoWiqgwooUqq9yPro=
-github.com/onsi/gomega v1.20.0 h1:8W0cWlwFkflGPLltQvLRB7ZVD5HuP6ng320w2IS245Q=
 github.com/onsi/gomega v1.20.0/go.mod h1:DtrZpjmvpn2mPm4YWQa0/ALMDj9v4YxLgojwPeREyVo=
+github.com/onsi/gomega v1.20.1/go.mod h1:DtrZpjmvpn2mPm4YWQa0/ALMDj9v4YxLgojwPeREyVo=
+github.com/onsi/gomega v1.21.1 h1:OB/euWYIExnPBohllTicTHmGTrMaqJ67nIu80j0/uEM=
+github.com/onsi/gomega v1.21.1/go.mod h1:iYAIXgPSaDHak0LCMA+AWBpIKBr8WZicMxnE8luStNc=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
@@ -252,6 +255,7 @@ github.com/yuin/goldmark v1.1.32/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9de
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 github.com/yuin/goldmark v1.4.1/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
+github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 go.opencensus.io v0.21.0/go.mod h1:mSImk1erAIZhrmZN+AvHh14ztQfjbGwt4TtuofqLduU=
 go.opencensus.io v0.22.0/go.mod h1:+kGneAE2xo2IficOXnaByMWTGM9T73dGwxeWcUqIpI8=
 go.opencensus.io v0.22.2/go.mod h1:yxeiOL68Rb0Xd1ddK5vPZ/oVn4vY4Ynel7k9FzqtOIw=
@@ -261,9 +265,10 @@ go.opencensus.io v0.22.5/go.mod h1:5pWMHQbX5EPX2/62yrJeAkowc+lfs/XD7Uxpq3pI6kk=
 go.opencensus.io v0.23.0/go.mod h1:XItmlyltB5F7CS4xOC1DcqMoFqwtC6OG2xF7mCv7P7E=
 go.opentelemetry.io/contrib/instrumentation/runtime v0.33.0 h1:YhjJQGhEoxXXKwH16MQEW37KgdZSACk+HyHnFtv/NcI=
 go.opentelemetry.io/contrib/instrumentation/runtime v0.33.0/go.mod h1:cu2qiP1YaeuJtMVDUuMJZPfCBqJr4GB9kkwXbg5knMA=
-go.opentelemetry.io/otel v1.4.1/go.mod h1:StM6F/0fSwpd8dKWDCdRr7uRvEPYdW0hBSlbdTiUde4=
-go.opentelemetry.io/otel v1.8.0 h1:zcvBFizPbpa1q7FehvFiHbQwGzmPILebO0tyqIR5Djg=
 go.opentelemetry.io/otel v1.8.0/go.mod h1:2pkj+iMj0o03Y+cW6/m8Y4WkRdYN3AvCXCnzRMp9yvM=
+go.opentelemetry.io/otel v1.9.0/go.mod h1:np4EoPGzoPs3O67xUVNoPPcmSvsfOxNlNA4F4AC+0Eo=
+go.opentelemetry.io/otel v1.10.0 h1:Y7DTJMR6zs1xkS/upamJYk0SxxN4C9AqRd77jmZnyY4=
+go.opentelemetry.io/otel v1.10.0/go.mod h1:NbvWjCthWHKBEUMpf0/v8ZRZlni86PpGFEMA9pnQSnQ=
 go.opentelemetry.io/otel/exporters/jaeger v1.8.0 h1:TLLqD6kDhLPziEC7pgPrMvP9lAqdk3n1gf8DiFSnfW8=
 go.opentelemetry.io/otel/exporters/jaeger v1.8.0/go.mod h1:GbWg+ng88rDtx+id26C34QLqw2erqJeAjsCx9AFeHfE=
 go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.8.0 h1:ao8CJIShCaIbaMsGxy+jp2YHSudketpDgDRcbirov78=
@@ -278,16 +283,18 @@ go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.8.0 h1:00hCSG
 go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.8.0/go.mod h1:twhIvtDQW2sWP1O2cT1N8nkSBgKCRZv2z6COTTBrf8Q=
 go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.8.0 h1:FVy7BZCjoA2Nk+fHqIdoTmm554J9wTX+YcrDp+mc368=
 go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.8.0/go.mod h1:ztncjvKpotSUQq7rlgPibGt8kZfSI3/jI8EO7JjuY2c=
-go.opentelemetry.io/otel/metric v0.31.0 h1:6SiklT+gfWAwWUR0meEMxQBtihpiEs4c+vL9spDTqUs=
 go.opentelemetry.io/otel/metric v0.31.0/go.mod h1:ohmwj9KTSIeBnDBm/ZwH2PSZxZzoOaG2xZeekTRzL5A=
-go.opentelemetry.io/otel/sdk v1.4.1/go.mod h1:NBwHDgDIBYjwK2WNu1OPgsIc2IJzmBXNnvIJxJc8BpE=
+go.opentelemetry.io/otel/metric v0.32.1 h1:ftff5LSBCIDwL0UkhBuDg8j9NNxx2IusvJ18q9h6RC4=
-go.opentelemetry.io/otel/sdk v1.8.0 h1:xwu69/fNuwbSHWe/0PGS888RmjWY181OmcXDQKu7ZQk=
+go.opentelemetry.io/otel/metric v0.32.1/go.mod h1:iLPP7FaKMAD5BIxJ2VX7f2KTuz//0QK2hEUyti5psqQ=
 go.opentelemetry.io/otel/sdk v1.8.0/go.mod h1:uPSfc+yfDH2StDM/Rm35WE8gXSNdvCg023J6HeGNO0c=
+go.opentelemetry.io/otel/sdk v1.9.0 h1:LNXp1vrr83fNXTHgU8eO89mhzxb/bbWAsHG6fNf3qWo=
+go.opentelemetry.io/otel/sdk v1.9.0/go.mod h1:AEZc8nt5bd2F7BC24J5R0mrjYnpEgYHyTcM/vrSple4=
 go.opentelemetry.io/otel/sdk/metric v0.31.0 h1:2sZx4R43ZMhJdteKAlKoHvRgrMp53V1aRxvEf5lCq8Q=
 go.opentelemetry.io/otel/sdk/metric v0.31.0/go.mod h1:fl0SmNnX9mN9xgU6OLYLMBMrNAsaZQi7qBwprwO3abk=
-go.opentelemetry.io/otel/trace v1.4.1/go.mod h1:iYEVbroFCNut9QkwEczV9vMRPHNKSSwYZjulEtsmhFc=
-go.opentelemetry.io/otel/trace v1.8.0 h1:cSy0DF9eGI5WIfNwZ1q2iUyGj00tGzP24dE1lOlHrfY=
 go.opentelemetry.io/otel/trace v1.8.0/go.mod h1:0Bt3PXY8w+3pheS3hQUt+wow8b1ojPaTBoTCh2zIFI4=
+go.opentelemetry.io/otel/trace v1.9.0/go.mod h1:2737Q0MuG8q1uILYm2YYVkAyLtOofiTNGg6VODnOiPo=
+go.opentelemetry.io/otel/trace v1.10.0 h1:npQMbR8o7mum8uF95yFbOEJffhs1sbCOfDh8zAJiH5E=
+go.opentelemetry.io/otel/trace v1.10.0/go.mod h1:Sij3YYczqAdz+EhmGhE6TpTxUO5/F/AzrK+kxfGqySM=
 go.opentelemetry.io/proto/otlp v0.7.0/go.mod h1:PqfVotwruBrMGOCsRd/89rSnXhoiJIqeYNgFYFoEGnI=
 go.opentelemetry.io/proto/otlp v0.18.0 h1:W5hyXNComRa23tGpKwG+FRAc4rfF6ZUg1JReK+QHS80=
 go.opentelemetry.io/proto/otlp v0.18.0/go.mod h1:H7XAot3MsfNsj7EXtrA2q5xSNQ10UqI405h3+duxN4U=
@@ -335,8 +342,9 @@ golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.1/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
-golang.org/x/mod v0.6.0-dev.0.20220106191415-9b9b3d81d5e3 h1:kQgndtyPBW/JIYERgdxfwMYh3AVStj88WQTlNDi2a+o=
 golang.org/x/mod v0.6.0-dev.0.20220106191415-9b9b3d81d5e3/go.mod h1:3p9vT2HGsQu2K1YbXdKPJLVgG5VJdoTa1poYQBtP1AY=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 h1:6zppjxzCulZykYSLyVDYbneBfbaBIQPYMevg0bEwv2s=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -419,6 +427,7 @@ golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220601150217-0de741cfad7f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -556,15 +565,15 @@ golang.org/x/tools v0.1.2/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.3/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.4/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.5/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
-golang.org/x/tools v0.1.10 h1:QjFRCZxdOhBJ/UNgnBZLbNV13DlbnK0quyivTnXJM20=
 golang.org/x/tools v0.1.10/go.mod h1:Uh6Zz+xoGYZom868N8YTex3t7RhtHDBrE8Gzo9bV56E=
+golang.org/x/tools v0.1.12 h1:VveCTK38A2rkS8ZqFY25HIDFscX5X9OoEhJd3quQmXU=
+golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20220411194840-2f41105eb62f/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20220517211312-f3a8303e98df/go.mod h1:K8+ghG5WaK9qNqU5K3HdILfMLy1f3aNYFI/wnl100a8=
-golang.org/x/xerrors v0.0.0-20220609144429-65e65417b02f h1:uF6paiQQebLeSXkrTqHqz0MXhXXS1KgF41eUdBNvxK0=
 golang.org/x/xerrors v0.0.0-20220609144429-65e65417b02f/go.mod h1:K8+ghG5WaK9qNqU5K3HdILfMLy1f3aNYFI/wnl100a8=
 google.golang.org/api v0.4.0/go.mod h1:8k5glujaEP+g9n7WNsDg8QP6cUVNI86fCNMcbazEtwE=
 google.golang.org/api v0.7.0/go.mod h1:WtwebWUNSVBH/HAw79HIFXZNqEvBhG+Ra+ax0hx3E3M=

example/otel/main.go

@@ -8,7 +8,6 @@ import (
 	"github.com/uptrace/opentelemetry-go-extra/otelplay"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/codes"
-	semconv "go.opentelemetry.io/otel/semconv/v1.7.0"
 
 	"github.com/go-redis/redis/extra/redisotel/v9"
 	"github.com/go-redis/redis/v9"
@@ -25,7 +24,9 @@ func main() {
 	rdb := redis.NewClient(&redis.Options{
 		Addr: ":6379",
 	})
-	rdb.AddHook(redisotel.NewTracingHook(redisotel.WithAttributes(semconv.NetPeerNameKey.String("localhost"), semconv.NetPeerPortKey.String("6379"))))
+	if err := redisotel.InstrumentTracing(rdb); err != nil {
+		panic(err)
+	}
 
 	ctx, span := tracer.Start(ctx, "handleRequest")
 	defer span.End()

example_instrumentation_test.go

@@ -3,6 +3,7 @@ package redis_test
 import (
 	"context"
 	"fmt"
+	"net"
 
 	"github.com/go-redis/redis/v9"
 )
@@ -11,24 +12,28 @@ type redisHook struct{}
 
 var _ redis.Hook = redisHook{}
 
-func (redisHook) BeforeProcess(ctx context.Context, cmd redis.Cmder) (context.Context, error) {
+func (redisHook) DialHook(hook redis.DialHook) redis.DialHook {
+	return func(ctx context.Context, network, addr string) (net.Conn, error) {
+		return hook(ctx, network, addr)
+	}
+}
+
+func (redisHook) ProcessHook(hook redis.ProcessHook) redis.ProcessHook {
+	return func(ctx context.Context, cmd redis.Cmder) error {
 		fmt.Printf("starting processing: <%s>\n", cmd)
-	return ctx, nil
+		err := hook(ctx, cmd)
-}
-
-func (redisHook) AfterProcess(ctx context.Context, cmd redis.Cmder) error {
 		fmt.Printf("finished processing: <%s>\n", cmd)
-	return nil
+		return err
+	}
 }
 
-func (redisHook) BeforeProcessPipeline(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+func (redisHook) ProcessPipelineHook(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
+	return func(ctx context.Context, cmds []redis.Cmder) error {
 		fmt.Printf("pipeline starting processing: %v\n", cmds)
-	return ctx, nil
+		err := hook(ctx, cmds)
-}
-
-func (redisHook) AfterProcessPipeline(ctx context.Context, cmds []redis.Cmder) error {
 		fmt.Printf("pipeline finished processing: %v\n", cmds)
-	return nil
+		return err
+	}
 }
 
 func Example_instrumentation() {

example_test.go

@@ -433,7 +433,7 @@ func ExampleClient_TxPipeline() {
 }
 
 func ExampleClient_Watch() {
-	const maxRetries = 1000
+	const maxRetries = 10000
 
 	// Increment transactionally increments key using GET and SET commands.
 	increment := func(key string) error {

extra/redisotel/config.go

@@ -0,0 +1,128 @@
+package redisotel
+
+import (
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/metric"
+	"go.opentelemetry.io/otel/metric/global"
+	semconv "go.opentelemetry.io/otel/semconv/v1.4.0"
+	"go.opentelemetry.io/otel/trace"
+)
+
+type config struct {
+	// Common options.
+
+	attrs []attribute.KeyValue
+
+	// Tracing options.
+
+	tp     trace.TracerProvider
+	tracer trace.Tracer
+
+	dbStmtEnabled bool
+
+	// Metrics options.
+
+	mp    metric.MeterProvider
+	meter metric.Meter
+
+	poolName string
+}
+
+type baseOption interface {
+	apply(conf *config)
+}
+
+type Option interface {
+	baseOption
+	tracing()
+	metrics()
+}
+
+type option func(conf *config)
+
+func (fn option) apply(conf *config) {
+	fn(conf)
+}
+
+func (fn option) tracing() {}
+
+func (fn option) metrics() {}
+
+func newConfig(opts ...baseOption) *config {
+	conf := &config{
+		tp: otel.GetTracerProvider(),
+		mp: global.MeterProvider(),
+		attrs: []attribute.KeyValue{
+			semconv.DBSystemRedis,
+		},
+		dbStmtEnabled: true,
+	}
+	for _, opt := range opts {
+		opt.apply(conf)
+	}
+	return conf
+}
+
+// WithAttributes specifies additional attributes to be added to the span.
+func WithAttributes(attrs ...attribute.KeyValue) Option {
+	return option(func(conf *config) {
+		conf.attrs = append(conf.attrs, attrs...)
+	})
+}
+
+//------------------------------------------------------------------------------
+
+type TracingOption interface {
+	baseOption
+	tracing()
+}
+
+type tracingOption func(conf *config)
+
+var _ TracingOption = (*tracingOption)(nil)
+
+func (fn tracingOption) apply(conf *config) {
+	fn(conf)
+}
+
+func (fn tracingOption) tracing() {}
+
+// WithTracerProvider specifies a tracer provider to use for creating a tracer.
+// If none is specified, the global provider is used.
+func WithTracerProvider(provider trace.TracerProvider) TracingOption {
+	return tracingOption(func(conf *config) {
+		conf.tp = provider
+	})
+}
+
+// WithDBStatement tells the tracing hook not to log raw redis commands.
+func WithDBStatement(on bool) TracingOption {
+	return tracingOption(func(conf *config) {
+		conf.dbStmtEnabled = on
+	})
+}
+
+//------------------------------------------------------------------------------
+
+type MetricsOption interface {
+	baseOption
+	metrics()
+}
+
+type metricsOption func(conf *config)
+
+var _ MetricsOption = (*metricsOption)(nil)
+
+func (fn metricsOption) apply(conf *config) {
+	fn(conf)
+}
+
+func (fn metricsOption) metrics() {}
+
+// WithMeterProvider configures a metric.Meter used to create instruments.
+func WithMeterProvider(mp metric.MeterProvider) MetricsOption {
+	return metricsOption(func(conf *config) {
+		conf.mp = mp
+	})
+}

extra/redisotel/go.mod

@@ -9,7 +9,8 @@ replace github.com/go-redis/redis/extra/rediscmd/v9 => ../rediscmd
 require (
 	github.com/go-redis/redis/extra/rediscmd/v9 v9.0.0-beta.2
 	github.com/go-redis/redis/v9 v9.0.0-beta.2
-	go.opentelemetry.io/otel v1.9.0
+	go.opentelemetry.io/otel v1.10.0
+	go.opentelemetry.io/otel/metric v0.32.1
 	go.opentelemetry.io/otel/sdk v1.9.0
-	go.opentelemetry.io/otel/trace v1.9.0
+	go.opentelemetry.io/otel/trace v1.10.0
 )

extra/redisotel/go.sum

@@ -67,12 +67,16 @@ github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.4.1/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
-go.opentelemetry.io/otel v1.9.0 h1:8WZNQFIB2a71LnANS9JeyidJKKGOOremcUtb/OtHISw=
 go.opentelemetry.io/otel v1.9.0/go.mod h1:np4EoPGzoPs3O67xUVNoPPcmSvsfOxNlNA4F4AC+0Eo=
+go.opentelemetry.io/otel v1.10.0 h1:Y7DTJMR6zs1xkS/upamJYk0SxxN4C9AqRd77jmZnyY4=
+go.opentelemetry.io/otel v1.10.0/go.mod h1:NbvWjCthWHKBEUMpf0/v8ZRZlni86PpGFEMA9pnQSnQ=
+go.opentelemetry.io/otel/metric v0.32.1 h1:ftff5LSBCIDwL0UkhBuDg8j9NNxx2IusvJ18q9h6RC4=
+go.opentelemetry.io/otel/metric v0.32.1/go.mod h1:iLPP7FaKMAD5BIxJ2VX7f2KTuz//0QK2hEUyti5psqQ=
 go.opentelemetry.io/otel/sdk v1.9.0 h1:LNXp1vrr83fNXTHgU8eO89mhzxb/bbWAsHG6fNf3qWo=
 go.opentelemetry.io/otel/sdk v1.9.0/go.mod h1:AEZc8nt5bd2F7BC24J5R0mrjYnpEgYHyTcM/vrSple4=
-go.opentelemetry.io/otel/trace v1.9.0 h1:oZaCNJUjWcg60VXWee8lJKlqhPbXAPB51URuR47pQYc=
 go.opentelemetry.io/otel/trace v1.9.0/go.mod h1:2737Q0MuG8q1uILYm2YYVkAyLtOofiTNGg6VODnOiPo=
+go.opentelemetry.io/otel/trace v1.10.0 h1:npQMbR8o7mum8uF95yFbOEJffhs1sbCOfDh8zAJiH5E=
+go.opentelemetry.io/otel/trace v1.10.0/go.mod h1:Sij3YYczqAdz+EhmGhE6TpTxUO5/F/AzrK+kxfGqySM=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=

extra/redisotel/metrics.go

@@ -0,0 +1,194 @@
+package redisotel
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"time"
+
+	"github.com/go-redis/redis/v9"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/metric"
+	"go.opentelemetry.io/otel/metric/instrument"
+	"go.opentelemetry.io/otel/metric/instrument/syncint64"
+)
+
+// InstrumentMetrics starts reporting OpenTelemetry Metrics.
+//
+// Based on https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/semantic_conventions/database-metrics.md
+func InstrumentMetrics(rdb redis.UniversalClient, opts ...MetricsOption) error {
+	baseOpts := make([]baseOption, len(opts))
+	for i, opt := range opts {
+		baseOpts[i] = opt
+	}
+	conf := newConfig(baseOpts...)
+
+	if conf.meter == nil {
+		conf.meter = conf.mp.Meter(
+			instrumName,
+			metric.WithInstrumentationVersion("semver:"+redis.Version()),
+		)
+	}
+
+	switch rdb := rdb.(type) {
+	case *redis.Client:
+		if conf.poolName == "" {
+			opt := rdb.Options()
+			conf.poolName = opt.Addr
+		}
+		conf.attrs = append(conf.attrs, attribute.String("pool.name", conf.poolName))
+
+		if err := reportPoolStats(rdb, conf); err != nil {
+			return err
+		}
+		if err := addMetricsHook(rdb, conf); err != nil {
+			return err
+		}
+		return nil
+	case *redis.ClusterClient:
+		rdb.OnNewNode(func(rdb *redis.Client) {
+			if conf.poolName == "" {
+				opt := rdb.Options()
+				conf.poolName = opt.Addr
+			}
+			conf.attrs = append(conf.attrs, attribute.String("pool.name", conf.poolName))
+
+			if err := reportPoolStats(rdb, conf); err != nil {
+				otel.Handle(err)
+			}
+			if err := addMetricsHook(rdb, conf); err != nil {
+				otel.Handle(err)
+			}
+		})
+		return nil
+	case *redis.Ring:
+		rdb.OnNewNode(func(rdb *redis.Client) {
+			if err := reportPoolStats(rdb, conf); err != nil {
+				otel.Handle(err)
+			}
+			if err := addMetricsHook(rdb, conf); err != nil {
+				otel.Handle(err)
+			}
+		})
+		return nil
+	default:
+		return fmt.Errorf("redisotel: %T not supported", rdb)
+	}
+}
+
+func reportPoolStats(rdb *redis.Client, conf *config) error {
+	labels := conf.attrs
+	idleAttrs := append(labels, attribute.String("state", "idle"))
+	usedAttrs := append(labels, attribute.String("state", "used"))
+
+	usage, err := conf.meter.AsyncInt64().UpDownCounter(
+		"db.client.connections.usage",
+		instrument.WithDescription("The number of connections that are currently in state described by the state attribute"),
+	)
+	if err != nil {
+		return err
+	}
+
+	timeouts, err := conf.meter.AsyncInt64().UpDownCounter(
+		"db.client.connections.timeouts",
+		instrument.WithDescription("The number of connection timeouts that have occurred trying to obtain a connection from the pool"),
+	)
+	if err != nil {
+		return err
+	}
+
+	return conf.meter.RegisterCallback(
+		[]instrument.Asynchronous{
+			usage,
+			timeouts,
+		},
+		func(ctx context.Context) {
+			stats := rdb.PoolStats()
+
+			usage.Observe(ctx, int64(stats.IdleConns), idleAttrs...)
+			usage.Observe(ctx, int64(stats.TotalConns-stats.IdleConns), usedAttrs...)
+
+			timeouts.Observe(ctx, int64(stats.Timeouts), labels...)
+		},
+	)
+}
+
+func addMetricsHook(rdb *redis.Client, conf *config) error {
+	createTime, err := conf.meter.SyncInt64().Histogram(
+		"db.client.connections.create_time",
+		instrument.WithDescription("The time it took to create a new connection."),
+		instrument.WithUnit("ms"),
+	)
+	if err != nil {
+		return err
+	}
+
+	useTime, err := conf.meter.SyncInt64().Histogram(
+		"db.client.connections.use_time",
+		instrument.WithDescription("The time between borrowing a connection and returning it to the pool."),
+		instrument.WithUnit("ms"),
+	)
+	if err != nil {
+		return err
+	}
+
+	rdb.AddHook(&metricsHook{
+		createTime: createTime,
+		useTime:    useTime,
+	})
+	return nil
+}
+
+type metricsHook struct {
+	createTime syncint64.Histogram
+	useTime    syncint64.Histogram
+}
+
+var _ redis.Hook = (*metricsHook)(nil)
+
+func (mh *metricsHook) DialHook(hook redis.DialHook) redis.DialHook {
+	return func(ctx context.Context, network, addr string) (net.Conn, error) {
+		start := time.Now()
+
+		conn, err := hook(ctx, network, addr)
+
+		mh.createTime.Record(ctx, time.Since(start).Milliseconds())
+		return conn, err
+	}
+}
+
+func (mh *metricsHook) ProcessHook(hook redis.ProcessHook) redis.ProcessHook {
+	return func(ctx context.Context, cmd redis.Cmder) error {
+		start := time.Now()
+
+		err := hook(ctx, cmd)
+
+		dur := time.Since(start).Milliseconds()
+		mh.useTime.Record(ctx, dur, attribute.String("type", "command"), statusAttr(err))
+
+		return err
+	}
+}
+
+func (mh *metricsHook) ProcessPipelineHook(
+	hook redis.ProcessPipelineHook,
+) redis.ProcessPipelineHook {
+	return func(ctx context.Context, cmds []redis.Cmder) error {
+		start := time.Now()
+
+		err := hook(ctx, cmds)
+
+		dur := time.Since(start).Milliseconds()
+		mh.useTime.Record(ctx, dur, attribute.String("type", "pipeline"), statusAttr(err))
+
+		return err
+	}
+}
+
+func statusAttr(err error) attribute.KeyValue {
+	if err != nil {
+		return attribute.String("status", "error")
+	}
+	return attribute.String("status", "ok")
+}

extra/redisotel/redisotel.go

@@ -1,153 +0,0 @@
-package redisotel
-
-import (
-	"context"
-
-	"go.opentelemetry.io/otel"
-	"go.opentelemetry.io/otel/attribute"
-	"go.opentelemetry.io/otel/codes"
-	semconv "go.opentelemetry.io/otel/semconv/v1.10.0"
-	"go.opentelemetry.io/otel/trace"
-
-	"github.com/go-redis/redis/extra/rediscmd/v9"
-	"github.com/go-redis/redis/v9"
-)
-
-const (
-	defaultTracerName = "github.com/go-redis/redis/extra/redisotel"
-)
-
-type TracingHook struct {
-	tracer        trace.Tracer
-	attrs         []attribute.KeyValue
-	dbStmtEnabled bool
-}
-
-func NewTracingHook(opts ...Option) *TracingHook {
-	cfg := &config{
-		tp: otel.GetTracerProvider(),
-		attrs: []attribute.KeyValue{
-			semconv.DBSystemRedis,
-		},
-		dbStmtEnabled: true,
-	}
-	for _, opt := range opts {
-		opt.apply(cfg)
-	}
-
-	tracer := cfg.tp.Tracer(
-		defaultTracerName,
-		trace.WithInstrumentationVersion("semver:"+redis.Version()),
-	)
-	return &TracingHook{tracer: tracer, attrs: cfg.attrs, dbStmtEnabled: cfg.dbStmtEnabled}
-}
-
-func (th *TracingHook) BeforeProcess(ctx context.Context, cmd redis.Cmder) (context.Context, error) {
-	if !trace.SpanFromContext(ctx).IsRecording() {
-		return ctx, nil
-	}
-
-	opts := []trace.SpanStartOption{
-		trace.WithSpanKind(trace.SpanKindClient),
-		trace.WithAttributes(th.attrs...),
-	}
-
-	if th.dbStmtEnabled {
-		opts = append(opts, trace.WithAttributes(semconv.DBStatementKey.String(rediscmd.CmdString(cmd))))
-	}
-
-	ctx, _ = th.tracer.Start(ctx, cmd.FullName(), opts...)
-
-	return ctx, nil
-}
-
-func (th *TracingHook) AfterProcess(ctx context.Context, cmd redis.Cmder) error {
-	span := trace.SpanFromContext(ctx)
-	if err := cmd.Err(); err != nil {
-		recordError(ctx, span, err)
-	}
-	span.End()
-	return nil
-}
-
-func (th *TracingHook) BeforeProcessPipeline(
-	ctx context.Context, cmds []redis.Cmder,
-) (context.Context, error) {
-	if !trace.SpanFromContext(ctx).IsRecording() {
-		return ctx, nil
-	}
-
-	opts := []trace.SpanStartOption{
-		trace.WithSpanKind(trace.SpanKindClient),
-		trace.WithAttributes(th.attrs...),
-		trace.WithAttributes(
-			attribute.Int("db.redis.num_cmd", len(cmds)),
-		),
-	}
-
-	summary, cmdsString := rediscmd.CmdsString(cmds)
-	if th.dbStmtEnabled {
-		opts = append(opts, trace.WithAttributes(semconv.DBStatementKey.String(cmdsString)))
-	}
-
-	ctx, _ = th.tracer.Start(ctx, "pipeline "+summary, opts...)
-
-	return ctx, nil
-}
-
-func (th *TracingHook) AfterProcessPipeline(ctx context.Context, cmds []redis.Cmder) error {
-	span := trace.SpanFromContext(ctx)
-	if err := cmds[0].Err(); err != nil {
-		recordError(ctx, span, err)
-	}
-	span.End()
-	return nil
-}
-
-func recordError(ctx context.Context, span trace.Span, err error) {
-	if err != redis.Nil {
-		span.RecordError(err)
-		span.SetStatus(codes.Error, err.Error())
-	}
-}
-
-type config struct {
-	tp            trace.TracerProvider
-	attrs         []attribute.KeyValue
-	dbStmtEnabled bool
-}
-
-// Option specifies instrumentation configuration options.
-type Option interface {
-	apply(*config)
-}
-
-type optionFunc func(*config)
-
-func (o optionFunc) apply(c *config) {
-	o(c)
-}
-
-// WithTracerProvider specifies a tracer provider to use for creating a tracer.
-// If none is specified, the global provider is used.
-func WithTracerProvider(provider trace.TracerProvider) Option {
-	return optionFunc(func(cfg *config) {
-		if provider != nil {
-			cfg.tp = provider
-		}
-	})
-}
-
-// WithAttributes specifies additional attributes to be added to the span.
-func WithAttributes(attrs ...attribute.KeyValue) Option {
-	return optionFunc(func(cfg *config) {
-		cfg.attrs = append(cfg.attrs, attrs...)
-	})
-}
-
-// WithDBStatement tells the tracing hook not to log raw redis commands.
-func WithDBStatement(on bool) Option {
-	return optionFunc(func(cfg *config) {
-		cfg.dbStmtEnabled = on
-	})
-}

extra/redisotel/redisotel_test.go

@@ -1,4 +1,4 @@
-package redisotel_test
+package redisotel
 
 import (
 	"context"
@@ -10,16 +10,9 @@ import (
 	sdktrace "go.opentelemetry.io/otel/sdk/trace"
 	"go.opentelemetry.io/otel/trace"
 
-	"github.com/go-redis/redis/extra/redisotel/v9"
 	"github.com/go-redis/redis/v9"
 )
 
-func TestNew(t *testing.T) {
-	// this also functions as a compile-time test that the
-	// TracingHook conforms to the Hook interface
-	var _ redis.Hook = redisotel.NewTracingHook()
-}
-
 type providerFunc func(name string, opts ...trace.TracerOption) trace.Tracer
 
 func (fn providerFunc) Tracer(name string, opts ...trace.TracerOption) trace.Tracer {
@@ -34,7 +27,7 @@ func TestNewWithTracerProvider(t *testing.T) {
 		return otel.GetTracerProvider().Tracer(name, opts...)
 	})
 
-	_ = redisotel.NewTracingHook(redisotel.WithTracerProvider(tp))
+	_ = newTracingHook("", WithTracerProvider(tp))
 
 	if !invoked {
 		t.Fatalf("did not call custom TraceProvider")
@@ -43,20 +36,12 @@ func TestNewWithTracerProvider(t *testing.T) {
 
 func TestNewWithAttributes(t *testing.T) {
 	provider := sdktrace.NewTracerProvider()
-	hook := redisotel.NewTracingHook(redisotel.WithTracerProvider(provider), redisotel.WithAttributes(semconv.NetPeerNameKey.String("localhost")))
+	hook := newTracingHook("", WithTracerProvider(provider), WithAttributes(semconv.NetPeerNameKey.String("localhost")))
 	ctx, span := provider.Tracer("redis-test").Start(context.TODO(), "redis-test")
 	cmd := redis.NewCmd(ctx, "ping")
 	defer span.End()
 
-	ctx, err := hook.BeforeProcess(ctx, cmd)
+	processHook := hook.ProcessHook(func(ctx context.Context, cmd redis.Cmder) error {
-	if err != nil {
-		t.Fatal(err)
-	}
-	err = hook.AfterProcess(ctx, cmd)
-	if err != nil {
-		t.Fatal(err)
-	}
-
 		attrs := trace.SpanFromContext(ctx).(sdktrace.ReadOnlySpan).Attributes()
 		if !(attrs[0] == semconv.DBSystemRedis) {
 			t.Fatalf("expected attrs[0] to be semconv.DBSystemRedis, got: %v", attrs[0])
@@ -67,31 +52,36 @@ func TestNewWithAttributes(t *testing.T) {
 		if !(attrs[2] == semconv.DBStatementKey.String("ping")) {
 			t.Fatalf("expected attrs[2] to be semconv.DBStatementKey.String(\"ping\"), got: %v", attrs[2])
 		}
+		return nil
+	})
+	err := processHook(ctx, cmd)
+	if err != nil {
+		t.Fatal(err)
+	}
 }
 
 func TestWithDBStatement(t *testing.T) {
 	provider := sdktrace.NewTracerProvider()
-	hook := redisotel.NewTracingHook(
+	hook := newTracingHook(
-		redisotel.WithTracerProvider(provider),
+		"",
-		redisotel.WithDBStatement(false),
+		WithTracerProvider(provider),
+		WithDBStatement(false),
 	)
 	ctx, span := provider.Tracer("redis-test").Start(context.TODO(), "redis-test")
 	cmd := redis.NewCmd(ctx, "ping")
 	defer span.End()
 
-	ctx, err := hook.BeforeProcess(ctx, cmd)
+	processHook := hook.ProcessHook(func(ctx context.Context, cmd redis.Cmder) error {
-	if err != nil {
-		t.Fatal(err)
-	}
-	err = hook.AfterProcess(ctx, cmd)
-	if err != nil {
-		t.Fatal(err)
-	}
-
 		attrs := trace.SpanFromContext(ctx).(sdktrace.ReadOnlySpan).Attributes()
 		for _, attr := range attrs {
 			if attr.Key == semconv.DBStatementKey {
 				t.Fatal("Attribute with db statement should not exist")
 			}
 		}
+		return nil
+	})
+	err := processHook(ctx, cmd)
+	if err != nil {
+		t.Fatal(err)
+	}
 }

extra/redisotel/tracing.go

@@ -0,0 +1,175 @@
+package redisotel
+
+import (
+	"context"
+	"fmt"
+	"net"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+	semconv "go.opentelemetry.io/otel/semconv/v1.10.0"
+	"go.opentelemetry.io/otel/trace"
+
+	"github.com/go-redis/redis/extra/rediscmd/v9"
+	"github.com/go-redis/redis/v9"
+)
+
+const (
+	instrumName = "github.com/go-redis/redis/extra/redisotel"
+)
+
+func InstrumentTracing(rdb redis.UniversalClient, opts ...TracingOption) error {
+	switch rdb := rdb.(type) {
+	case *redis.Client:
+		opt := rdb.Options()
+		connString := formatDBConnString(opt.Network, opt.Addr)
+		rdb.AddHook(newTracingHook(connString, opts...))
+		return nil
+	case *redis.ClusterClient:
+		rdb.AddHook(newTracingHook("", opts...))
+
+		rdb.OnNewNode(func(rdb *redis.Client) {
+			opt := rdb.Options()
+			connString := formatDBConnString(opt.Network, opt.Addr)
+			rdb.AddHook(newTracingHook(connString, opts...))
+		})
+		return nil
+	case *redis.Ring:
+		rdb.AddHook(newTracingHook("", opts...))
+
+		rdb.OnNewNode(func(rdb *redis.Client) {
+			opt := rdb.Options()
+			connString := formatDBConnString(opt.Network, opt.Addr)
+			rdb.AddHook(newTracingHook(connString, opts...))
+		})
+		return nil
+	default:
+		return fmt.Errorf("redisotel: %T not supported", rdb)
+	}
+}
+
+type tracingHook struct {
+	conf *config
+
+	spanOpts []trace.SpanStartOption
+}
+
+var _ redis.Hook = (*tracingHook)(nil)
+
+func newTracingHook(connString string, opts ...TracingOption) *tracingHook {
+	baseOpts := make([]baseOption, len(opts))
+	for i, opt := range opts {
+		baseOpts[i] = opt
+	}
+	conf := newConfig(baseOpts...)
+
+	if conf.tracer == nil {
+		conf.tracer = conf.tp.Tracer(
+			instrumName,
+			trace.WithInstrumentationVersion("semver:"+redis.Version()),
+		)
+	}
+	if connString != "" {
+		conf.attrs = append(conf.attrs, semconv.DBConnectionStringKey.String(connString))
+	}
+
+	return &tracingHook{
+		conf: conf,
+
+		spanOpts: []trace.SpanStartOption{
+			trace.WithSpanKind(trace.SpanKindClient),
+			trace.WithAttributes(conf.attrs...),
+		},
+	}
+}
+
+func (th *tracingHook) DialHook(hook redis.DialHook) redis.DialHook {
+	return func(ctx context.Context, network, addr string) (net.Conn, error) {
+		if !trace.SpanFromContext(ctx).IsRecording() {
+			return hook(ctx, network, addr)
+		}
+
+		spanOpts := th.spanOpts
+		spanOpts = append(spanOpts, trace.WithAttributes(
+			attribute.String("network", network),
+			attribute.String("addr", addr),
+		))
+
+		ctx, span := th.conf.tracer.Start(ctx, "redis.dial", spanOpts...)
+		defer span.End()
+
+		conn, err := hook(ctx, network, addr)
+		if err != nil {
+			recordError(ctx, span, err)
+			return nil, err
+		}
+		return conn, nil
+	}
+}
+
+func (th *tracingHook) ProcessHook(hook redis.ProcessHook) redis.ProcessHook {
+	return func(ctx context.Context, cmd redis.Cmder) error {
+		if !trace.SpanFromContext(ctx).IsRecording() {
+			return hook(ctx, cmd)
+		}
+
+		opts := th.spanOpts
+		if th.conf.dbStmtEnabled {
+			opts = append(opts, trace.WithAttributes(
+				semconv.DBStatementKey.String(rediscmd.CmdString(cmd))),
+			)
+		}
+
+		ctx, span := th.conf.tracer.Start(ctx, cmd.FullName(), opts...)
+		defer span.End()
+
+		if err := hook(ctx, cmd); err != nil {
+			recordError(ctx, span, err)
+			return err
+		}
+		return nil
+	}
+}
+
+func (th *tracingHook) ProcessPipelineHook(
+	hook redis.ProcessPipelineHook,
+) redis.ProcessPipelineHook {
+	return func(ctx context.Context, cmds []redis.Cmder) error {
+		if !trace.SpanFromContext(ctx).IsRecording() {
+			return hook(ctx, cmds)
+		}
+
+		opts := th.spanOpts
+		opts = append(opts, trace.WithAttributes(
+			attribute.Int("db.redis.num_cmd", len(cmds)),
+		))
+
+		summary, cmdsString := rediscmd.CmdsString(cmds)
+		if th.conf.dbStmtEnabled {
+			opts = append(opts, trace.WithAttributes(semconv.DBStatementKey.String(cmdsString)))
+		}
+
+		ctx, span := th.conf.tracer.Start(ctx, "redis.pipeline "+summary, opts...)
+		defer span.End()
+
+		if err := hook(ctx, cmds); err != nil {
+			recordError(ctx, span, err)
+			return err
+		}
+		return nil
+	}
+}
+
+func recordError(ctx context.Context, span trace.Span, err error) {
+	if err != redis.Nil {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, err.Error())
+	}
+}
+
+func formatDBConnString(network, addr string) string {
+	if network == "tcp" {
+		network = "redis"
+	}
+	return fmt.Sprintf("%s://%s", network, addr)
+}

main_test.go

@@ -1,7 +1,6 @@
 package redis_test
 
 import (
-	"context"
 	"fmt"
 	"net"
 	"os"
@@ -416,37 +415,28 @@ func (cn *badConn) Write([]byte) (int, error) {
 //------------------------------------------------------------------------------
 
 type hook struct {
-	beforeProcess func(ctx context.Context, cmd redis.Cmder) (context.Context, error)
+	dialHook            func(hook redis.DialHook) redis.DialHook
-	afterProcess  func(ctx context.Context, cmd redis.Cmder) error
+	processHook         func(hook redis.ProcessHook) redis.ProcessHook
-
+	processPipelineHook func(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook
-	beforeProcessPipeline func(ctx context.Context, cmds []redis.Cmder) (context.Context, error)
-	afterProcessPipeline  func(ctx context.Context, cmds []redis.Cmder) error
 }
 
-func (h *hook) BeforeProcess(ctx context.Context, cmd redis.Cmder) (context.Context, error) {
+func (h *hook) DialHook(hook redis.DialHook) redis.DialHook {
-	if h.beforeProcess != nil {
+	if h.dialHook != nil {
-		return h.beforeProcess(ctx, cmd)
+		return h.dialHook(hook)
 	}
-	return ctx, nil
+	return hook
 }
 
-func (h *hook) AfterProcess(ctx context.Context, cmd redis.Cmder) error {
+func (h *hook) ProcessHook(hook redis.ProcessHook) redis.ProcessHook {
-	if h.afterProcess != nil {
+	if h.processHook != nil {
-		return h.afterProcess(ctx, cmd)
+		return h.processHook(hook)
 	}
-	return nil
+	return hook
 }
 
-func (h *hook) BeforeProcessPipeline(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+func (h *hook) ProcessPipelineHook(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
-	if h.beforeProcessPipeline != nil {
+	if h.processPipelineHook != nil {
-		return h.beforeProcessPipeline(ctx, cmds)
+		return h.processPipelineHook(hook)
 	}
-	return ctx, nil
+	return hook
-}
-
-func (h *hook) AfterProcessPipeline(ctx context.Context, cmds []redis.Cmder) error {
-	if h.afterProcessPipeline != nil {
-		return h.afterProcessPipeline(ctx, cmds)
-	}
-	return nil
 }

options.go

@@ -470,10 +470,13 @@ func getUserPassword(u *url.URL) (string, string) {
 	return user, password
 }
 
-func newConnPool(opt *Options) *pool.ConnPool {
+func newConnPool(
+	opt *Options,
+	dialer func(ctx context.Context, network, addr string) (net.Conn, error),
+) *pool.ConnPool {
 	return pool.NewConnPool(&pool.Options{
 		Dialer: func(ctx context.Context) (net.Conn, error) {
-			return opt.Dialer(ctx, opt.Network, opt.Addr)
+			return dialer(ctx, opt.Network, opt.Addr)
 		},
 		PoolFIFO:        opt.PoolFIFO,
 		PoolSize:        opt.PoolSize,

redis.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"net"
 	"strings"
 	"sync/atomic"
 	"time"
@@ -24,102 +25,104 @@ func SetLogger(logger internal.Logging) {
 //------------------------------------------------------------------------------
 
 type Hook interface {
-	BeforeProcess(ctx context.Context, cmd Cmder) (context.Context, error)
+	DialHook(hook DialHook) DialHook
-	AfterProcess(ctx context.Context, cmd Cmder) error
+	ProcessHook(hook ProcessHook) ProcessHook
-
+	ProcessPipelineHook(hook ProcessPipelineHook) ProcessPipelineHook
-	BeforeProcessPipeline(ctx context.Context, cmds []Cmder) (context.Context, error)
-	AfterProcessPipeline(ctx context.Context, cmds []Cmder) error
 }
 
+type (
+	DialHook            func(ctx context.Context, network, addr string) (net.Conn, error)
+	ProcessHook         func(ctx context.Context, cmd Cmder) error
+	ProcessPipelineHook func(ctx context.Context, cmds []Cmder) error
+)
+
 type hooks struct {
-	hooks []Hook
+	slice             []Hook
-}
+	dial              DialHook
-
+	process           ProcessHook
-func (hs *hooks) lock() {
+	processPipeline   ProcessPipelineHook
-	hs.hooks = hs.hooks[:len(hs.hooks):len(hs.hooks)]
+	processTxPipeline ProcessPipelineHook
-}
-
-func (hs hooks) clone() hooks {
-	clone := hs
-	clone.lock()
-	return clone
 }
 
 func (hs *hooks) AddHook(hook Hook) {
-	hs.hooks = append(hs.hooks, hook)
+	if hs.process == nil {
+		panic("hs.process == nil")
+	}
+	if hs.processPipeline == nil {
+		panic("hs.processPipeline == nil")
+	}
+	if hs.processTxPipeline == nil {
+		panic("hs.processTxPipeline == nil")
+	}
+
+	hs.slice = append(hs.slice, hook)
+	hs.dial = hook.DialHook(hs.dial)
+	hs.process = hook.ProcessHook(hs.process)
+	hs.processPipeline = hook.ProcessPipelineHook(hs.processPipeline)
+	hs.processTxPipeline = hook.ProcessPipelineHook(hs.processTxPipeline)
 }
 
-func (hs hooks) process(
+func (hs *hooks) clone() hooks {
-	ctx context.Context, cmd Cmder, fn func(context.Context, Cmder) error,
+	clone := *hs
-) error {
+	l := len(clone.slice)
-	if len(hs.hooks) == 0 {
+	clone.slice = clone.slice[:l:l]
-		err := fn(ctx, cmd)
+	return clone
-		cmd.SetErr(err)
-		return err
-	}
-
-	var hookIndex int
-	var retErr error
-
-	for ; hookIndex < len(hs.hooks) && retErr == nil; hookIndex++ {
-		ctx, retErr = hs.hooks[hookIndex].BeforeProcess(ctx, cmd)
-		if retErr != nil {
-			cmd.SetErr(retErr)
-		}
-	}
-
-	if retErr == nil {
-		retErr = fn(ctx, cmd)
-		cmd.SetErr(retErr)
-	}
-
-	for hookIndex--; hookIndex >= 0; hookIndex-- {
-		if err := hs.hooks[hookIndex].AfterProcess(ctx, cmd); err != nil {
-			retErr = err
-			cmd.SetErr(retErr)
-		}
-	}
-
-	return retErr
 }
 
-func (hs hooks) processPipeline(
+func (hs *hooks) setDial(dial DialHook) {
-	ctx context.Context, cmds []Cmder, fn func(context.Context, []Cmder) error,
+	hs.dial = dial
-) error {
+	for _, h := range hs.slice {
-	if len(hs.hooks) == 0 {
+		if wrapped := h.DialHook(hs.dial); wrapped != nil {
-		err := fn(ctx, cmds)
+			hs.dial = wrapped
-		return err
-	}
-
-	var hookIndex int
-	var retErr error
-
-	for ; hookIndex < len(hs.hooks) && retErr == nil; hookIndex++ {
-		ctx, retErr = hs.hooks[hookIndex].BeforeProcessPipeline(ctx, cmds)
-		if retErr != nil {
-			setCmdsErr(cmds, retErr)
 		}
 	}
-
-	if retErr == nil {
-		retErr = fn(ctx, cmds)
-	}
-
-	for hookIndex--; hookIndex >= 0; hookIndex-- {
-		if err := hs.hooks[hookIndex].AfterProcessPipeline(ctx, cmds); err != nil {
-			retErr = err
-			setCmdsErr(cmds, retErr)
-		}
-	}
-
-	return retErr
 }
 
-func (hs hooks) processTxPipeline(
+func (hs *hooks) setProcess(process ProcessHook) {
-	ctx context.Context, cmds []Cmder, fn func(context.Context, []Cmder) error,
+	hs.process = process
+	for _, h := range hs.slice {
+		if wrapped := h.ProcessHook(hs.process); wrapped != nil {
+			hs.process = wrapped
+		}
+	}
+}
+
+func (hs *hooks) setProcessPipeline(processPipeline ProcessPipelineHook) {
+	hs.processPipeline = processPipeline
+	for _, h := range hs.slice {
+		if wrapped := h.ProcessPipelineHook(hs.processPipeline); wrapped != nil {
+			hs.processPipeline = wrapped
+		}
+	}
+}
+
+func (hs *hooks) setProcessTxPipeline(processTxPipeline ProcessPipelineHook) {
+	hs.processTxPipeline = processTxPipeline
+	for _, h := range hs.slice {
+		if wrapped := h.ProcessPipelineHook(hs.processTxPipeline); wrapped != nil {
+			hs.processTxPipeline = wrapped
+		}
+	}
+}
+
+func (hs *hooks) withProcessHook(ctx context.Context, cmd Cmder, hook ProcessHook) error {
+	for _, h := range hs.slice {
+		if wrapped := h.ProcessHook(hook); wrapped != nil {
+			hook = wrapped
+		}
+	}
+	return hook(ctx, cmd)
+}
+
+func (hs *hooks) withProcessPipelineHook(
+	ctx context.Context, cmds []Cmder, hook ProcessPipelineHook,
 ) error {
-	cmds = wrapMultiExec(ctx, cmds)
+	for _, h := range hs.slice {
-	return hs.processPipeline(ctx, cmds, fn)
+		if wrapped := h.ProcessPipelineHook(hook); wrapped != nil {
+			hook = wrapped
+		}
+	}
+	return hook(ctx, cmds)
 }
 
 //------------------------------------------------------------------------------
@@ -131,13 +134,6 @@ type baseClient struct {
 	onClose func() error // hook called when client is closed
 }
 
-func newBaseClient(opt *Options, connPool pool.Pooler) *baseClient {
-	return &baseClient{
-		opt:      opt,
-		connPool: connPool,
-	}
-}
-
 func (c *baseClient) clone() *baseClient {
 	clone := *c
 	return &clone
@@ -293,6 +289,10 @@ func (c *baseClient) withConn(
 	return fn(ctx, cn)
 }
 
+func (c *baseClient) dial(ctx context.Context, network, addr string) (net.Conn, error) {
+	return c.opt.Dialer(ctx, network, addr)
+}
+
 func (c *baseClient) process(ctx context.Context, cmd Cmder) error {
 	var lastErr error
 	for attempt := 0; attempt <= c.opt.MaxRetries; attempt++ {
@@ -379,26 +379,22 @@ func (c *baseClient) getAddr() string {
 }
 
 func (c *baseClient) processPipeline(ctx context.Context, cmds []Cmder) error {
-	return c.generalProcessPipeline(ctx, cmds, c.pipelineProcessCmds)
+	if err := c.generalProcessPipeline(ctx, cmds, c.pipelineProcessCmds); err != nil {
-}
-
-func (c *baseClient) processTxPipeline(ctx context.Context, cmds []Cmder) error {
-	return c.generalProcessPipeline(ctx, cmds, c.txPipelineProcessCmds)
-}
-
-type pipelineProcessor func(context.Context, *pool.Conn, []Cmder) (bool, error)
-
-func (c *baseClient) generalProcessPipeline(
-	ctx context.Context, cmds []Cmder, p pipelineProcessor,
-) error {
-	err := c._generalProcessPipeline(ctx, cmds, p)
-	if err != nil {
 		return err
 	}
 	return cmdsFirstErr(cmds)
 }
 
-func (c *baseClient) _generalProcessPipeline(
+func (c *baseClient) processTxPipeline(ctx context.Context, cmds []Cmder) error {
+	if err := c.generalProcessPipeline(ctx, cmds, c.txPipelineProcessCmds); err != nil {
+		return err
+	}
+	return cmdsFirstErr(cmds)
+}
+
+type pipelineProcessor func(context.Context, *pool.Conn, []Cmder) (bool, error)
+
+func (c *baseClient) generalProcessPipeline(
 	ctx context.Context, cmds []Cmder, p pipelineProcessor,
 ) error {
 	var lastErr error
@@ -484,17 +480,6 @@ func (c *baseClient) txPipelineProcessCmds(
 	return false, nil
 }
 
-func wrapMultiExec(ctx context.Context, cmds []Cmder) []Cmder {
-	if len(cmds) == 0 {
-		panic("not reached")
-	}
-	cmdCopy := make([]Cmder, len(cmds)+2)
-	cmdCopy[0] = NewStatusCmd(ctx, "multi")
-	copy(cmdCopy[1:], cmds)
-	cmdCopy[len(cmdCopy)-1] = NewSliceCmd(ctx, "exec")
-	return cmdCopy
-}
-
 func txPipelineReadQueued(rd *proto.Reader, statusCmd *StatusCmd, cmds []Cmder) error {
 	// Parse +OK.
 	if err := statusCmd.readReply(rd); err != nil {
@@ -549,24 +534,29 @@ func NewClient(opt *Options) *Client {
 	opt.init()
 
 	c := Client{
-		baseClient: newBaseClient(opt, newConnPool(opt)),
+		baseClient: &baseClient{
+			opt: opt,
+		},
 	}
-	c.cmdable = c.Process
+	c.connPool = newConnPool(opt, c.baseClient.dial)
+	c.init()
 
 	return &c
 }
 
-func (c *Client) clone() *Client {
+func (c *Client) init() {
-	clone := *c
+	c.cmdable = c.Process
-	clone.cmdable = clone.Process
+	c.hooks.setDial(c.baseClient.dial)
-	clone.hooks.lock()
+	c.hooks.setProcess(c.baseClient.process)
-	return &clone
+	c.hooks.setProcessPipeline(c.baseClient.processPipeline)
+	c.hooks.setProcessTxPipeline(c.baseClient.processTxPipeline)
 }
 
 func (c *Client) WithTimeout(timeout time.Duration) *Client {
-	clone := c.clone()
+	clone := *c
 	clone.baseClient = c.baseClient.withTimeout(timeout)
-	return clone
+	clone.init()
+	return &clone
 }
 
 func (c *Client) Conn() *Conn {
@@ -581,15 +571,9 @@ func (c *Client) Do(ctx context.Context, args ...interface{}) *Cmd {
 }
 
 func (c *Client) Process(ctx context.Context, cmd Cmder) error {
-	return c.hooks.process(ctx, cmd, c.baseClient.process)
+	err := c.hooks.process(ctx, cmd)
-}
+	cmd.SetErr(err)
-
+	return err
-func (c *Client) processPipeline(ctx context.Context, cmds []Cmder) error {
-	return c.hooks.processPipeline(ctx, cmds, c.baseClient.processPipeline)
-}
-
-func (c *Client) processTxPipeline(ctx context.Context, cmds []Cmder) error {
-	return c.hooks.processTxPipeline(ctx, cmds, c.baseClient.processTxPipeline)
 }
 
 // Options returns read-only Options that were used to create the client.
@@ -611,7 +595,7 @@ func (c *Client) Pipelined(ctx context.Context, fn func(Pipeliner) error) ([]Cmd
 
 func (c *Client) Pipeline() Pipeliner {
 	pipe := Pipeline{
-		exec: c.processPipeline,
+		exec: pipelineExecer(c.hooks.processPipeline),
 	}
 	pipe.init()
 	return &pipe
@@ -624,7 +608,10 @@ func (c *Client) TxPipelined(ctx context.Context, fn func(Pipeliner) error) ([]C
 // TxPipeline acts like Pipeline, but wraps queued commands with MULTI/EXEC.
 func (c *Client) TxPipeline() Pipeliner {
 	pipe := Pipeline{
-		exec: c.processTxPipeline,
+		exec: func(ctx context.Context, cmds []Cmder) error {
+			cmds = wrapMultiExec(ctx, cmds)
+			return c.hooks.processTxPipeline(ctx, cmds)
+		},
 	}
 	pipe.init()
 	return &pipe
@@ -699,44 +686,47 @@ func (c *Client) SSubscribe(ctx context.Context, channels ...string) *PubSub {
 
 //------------------------------------------------------------------------------
 
-type conn struct {
-	baseClient
-	cmdable
-	statefulCmdable
-	hooks // TODO: inherit hooks
-}
-
 // Conn represents a single Redis connection rather than a pool of connections.
 // Prefer running commands from Client unless there is a specific need
 // for a continuous single Redis connection.
 type Conn struct {
-	*conn
+	baseClient
+	cmdable
+	statefulCmdable
+	hooks
 }
 
 func newConn(opt *Options, connPool pool.Pooler) *Conn {
 	c := Conn{
-		conn: &conn{
 		baseClient: baseClient{
 			opt:      opt,
 			connPool: connPool,
 		},
-		},
 	}
+
 	c.cmdable = c.Process
 	c.statefulCmdable = c.Process
+
+	c.hooks.setDial(c.baseClient.dial)
+	c.hooks.setProcess(c.baseClient.process)
+	c.hooks.setProcessPipeline(c.baseClient.processPipeline)
+	c.hooks.setProcessTxPipeline(c.baseClient.processTxPipeline)
+
 	return &c
 }
 
 func (c *Conn) Process(ctx context.Context, cmd Cmder) error {
-	return c.hooks.process(ctx, cmd, c.baseClient.process)
+	err := c.hooks.process(ctx, cmd)
+	cmd.SetErr(err)
+	return err
 }
 
 func (c *Conn) processPipeline(ctx context.Context, cmds []Cmder) error {
-	return c.hooks.processPipeline(ctx, cmds, c.baseClient.processPipeline)
+	return c.hooks.processPipeline(ctx, cmds)
 }
 
 func (c *Conn) processTxPipeline(ctx context.Context, cmds []Cmder) error {
-	return c.hooks.processTxPipeline(ctx, cmds, c.baseClient.processTxPipeline)
+	return c.hooks.processTxPipeline(ctx, cmds)
 }
 
 func (c *Conn) Pipelined(ctx context.Context, fn func(Pipeliner) error) ([]Cmder, error) {

redis_test.go

@@ -14,18 +14,22 @@ import (
 	"github.com/go-redis/redis/v9"
 )
 
-type redisHookError struct {
+type redisHookError struct{}
-	redis.Hook
-}
 
 var _ redis.Hook = redisHookError{}
 
-func (redisHookError) BeforeProcess(ctx context.Context, cmd redis.Cmder) (context.Context, error) {
+func (redisHookError) DialHook(hook redis.DialHook) redis.DialHook {
-	return ctx, nil
+	return hook
 }
 
-func (redisHookError) AfterProcess(ctx context.Context, cmd redis.Cmder) error {
+func (redisHookError) ProcessHook(hook redis.ProcessHook) redis.ProcessHook {
+	return func(ctx context.Context, cmd redis.Cmder) error {
 		return errors.New("hook error")
+	}
+}
+
+func (redisHookError) ProcessPipelineHook(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
+	return hook
 }
 
 func TestHookError(t *testing.T) {

ring.go

@@ -218,6 +218,7 @@ type ringSharding struct {
 	closed    bool
 	hash      ConsistentHash
 	numShard  int
+	onNewNode []func(rdb *Client)
 }
 
 type ringShards struct {
@@ -234,6 +235,12 @@ func newRingSharding(opt *RingOptions) *ringSharding {
 	return c
 }
 
+func (c *ringSharding) OnNewNode(fn func(rdb *Client)) {
+	c.mu.Lock()
+	c.onNewNode = append(c.onNewNode, fn)
+	c.mu.Unlock()
+}
+
 // SetAddrs replaces the shards in use, such that you can increase and
 // decrease number of shards, that you use. It will reuse shards that
 // existed before and close the ones that will not be used anymore.
@@ -245,7 +252,7 @@ func (c *ringSharding) SetAddrs(addrs map[string]string) {
 		return
 	}
 
-	shards, cleanup := newRingShards(c.opt, addrs, c.shards)
+	shards, cleanup := c.newRingShards(addrs, c.shards)
 	c.shards = shards
 	c.mu.Unlock()
 
@@ -253,8 +260,8 @@ func (c *ringSharding) SetAddrs(addrs map[string]string) {
 	cleanup()
 }
 
-func newRingShards(
+func (c *ringSharding) newRingShards(
-	opt *RingOptions, addrs map[string]string, existingShards *ringShards,
+	addrs map[string]string, existingShards *ringShards,
 ) (*ringShards, func()) {
 	shardMap := make(map[string]*ringShard)     // indexed by addr
 	unusedShards := make(map[string]*ringShard) // indexed by addr
@@ -276,7 +283,12 @@ func newRingShards(
 			shards.m[name] = shard
 			delete(unusedShards, addr)
 		} else {
-			shards.m[name] = newRingShard(opt, addr)
+			shard := newRingShard(c.opt, addr)
+			shards.m[name] = shard
+
+			for _, fn := range c.onNewNode {
+				fn(shard.Client)
+			}
 		}
 	}
 
@@ -460,13 +472,13 @@ func (c *ringSharding) Close() error {
 // and can tolerate losing data when one of the servers dies.
 // Otherwise you should use Redis Cluster.
 type Ring struct {
+	cmdable
+	hooks
+
 	opt               *RingOptions
 	sharding          *ringSharding
 	cmdsInfoCache     *cmdsInfoCache
 	heartbeatCancelFn context.CancelFunc
-
-	cmdable
-	hooks
 }
 
 func NewRing(opt *RingOptions) *Ring {
@@ -483,6 +495,14 @@ func NewRing(opt *RingOptions) *Ring {
 	ring.cmdsInfoCache = newCmdsInfoCache(ring.cmdsInfo)
 	ring.cmdable = ring.Process
 
+	ring.hooks.process = ring.process
+	ring.hooks.processPipeline = func(ctx context.Context, cmds []Cmder) error {
+		return ring.generalProcessPipeline(ctx, cmds, false)
+	}
+	ring.hooks.processTxPipeline = func(ctx context.Context, cmds []Cmder) error {
+		return ring.generalProcessPipeline(ctx, cmds, true)
+	}
+
 	go ring.sharding.Heartbeat(hbCtx, opt.HeartbeatFrequency)
 
 	return &ring
@@ -500,7 +520,9 @@ func (c *Ring) Do(ctx context.Context, args ...interface{}) *Cmd {
 }
 
 func (c *Ring) Process(ctx context.Context, cmd Cmder) error {
-	return c.hooks.process(ctx, cmd, c.process)
+	err := c.hooks.process(ctx, cmd)
+	cmd.SetErr(err)
+	return err
 }
 
 // Options returns read-only Options that were used to create the client.
@@ -573,6 +595,10 @@ func (c *Ring) SSubscribe(ctx context.Context, channels ...string) *PubSub {
 	return shard.Client.SSubscribe(ctx, channels...)
 }
 
+func (c *Ring) OnNewNode(fn func(rdb *Client)) {
+	c.sharding.OnNewNode(fn)
+}
+
 // ForEachShard concurrently calls the fn on each live shard in the ring.
 // It returns the first error if any.
 func (c *Ring) ForEachShard(
@@ -677,40 +703,37 @@ func (c *Ring) Pipelined(ctx context.Context, fn func(Pipeliner) error) ([]Cmder
 
 func (c *Ring) Pipeline() Pipeliner {
 	pipe := Pipeline{
-		exec: c.processPipeline,
+		exec: pipelineExecer(c.hooks.processPipeline),
 	}
 	pipe.init()
 	return &pipe
 }
 
-func (c *Ring) processPipeline(ctx context.Context, cmds []Cmder) error {
-	return c.hooks.processPipeline(ctx, cmds, func(ctx context.Context, cmds []Cmder) error {
-		return c.generalProcessPipeline(ctx, cmds, false)
-	})
-}
-
 func (c *Ring) TxPipelined(ctx context.Context, fn func(Pipeliner) error) ([]Cmder, error) {
 	return c.TxPipeline().Pipelined(ctx, fn)
 }
 
 func (c *Ring) TxPipeline() Pipeliner {
 	pipe := Pipeline{
-		exec: c.processTxPipeline,
+		exec: func(ctx context.Context, cmds []Cmder) error {
+			cmds = wrapMultiExec(ctx, cmds)
+			return c.hooks.processTxPipeline(ctx, cmds)
+		},
 	}
 	pipe.init()
 	return &pipe
 }
 
-func (c *Ring) processTxPipeline(ctx context.Context, cmds []Cmder) error {
-	return c.hooks.processPipeline(ctx, cmds, func(ctx context.Context, cmds []Cmder) error {
-		return c.generalProcessPipeline(ctx, cmds, true)
-	})
-}
-
 func (c *Ring) generalProcessPipeline(
 	ctx context.Context, cmds []Cmder, tx bool,
 ) error {
+	if tx {
+		// Trim multi .. exec.
+		cmds = cmds[1 : len(cmds)-1]
+	}
+
 	cmdsMap := make(map[string][]Cmder)
+
 	for _, cmd := range cmds {
 		cmdInfo := c.cmdInfo(ctx, cmd.Name())
 		hash := cmd.stringArg(cmdFirstKeyPos(cmd, cmdInfo))
@@ -726,7 +749,19 @@ func (c *Ring) generalProcessPipeline(
 		go func(hash string, cmds []Cmder) {
 			defer wg.Done()
 
-			_ = c.processShardPipeline(ctx, hash, cmds, tx)
+			// TODO: retry?
+			shard, err := c.sharding.GetByName(hash)
+			if err != nil {
+				setCmdsErr(cmds, err)
+				return
+			}
+
+			if tx {
+				cmds = wrapMultiExec(ctx, cmds)
+				shard.Client.hooks.processTxPipeline(ctx, cmds)
+			} else {
+				shard.Client.hooks.processPipeline(ctx, cmds)
+			}
 		}(hash, cmds)
 	}
 
@@ -734,28 +769,13 @@ func (c *Ring) generalProcessPipeline(
 	return cmdsFirstErr(cmds)
 }
 
-func (c *Ring) processShardPipeline(
-	ctx context.Context, hash string, cmds []Cmder, tx bool,
-) error {
-	// TODO: retry?
-	shard, err := c.sharding.GetByName(hash)
-	if err != nil {
-		setCmdsErr(cmds, err)
-		return err
-	}
-
-	if tx {
-		return shard.Client.processTxPipeline(ctx, cmds)
-	}
-	return shard.Client.processPipeline(ctx, cmds)
-}
-
 func (c *Ring) Watch(ctx context.Context, fn func(*Tx) error, keys ...string) error {
 	if len(keys) == 0 {
 		return fmt.Errorf("redis: Watch requires at least one key")
 	}
 
 	var shards []*ringShard
+
 	for _, key := range keys {
 		if key != "" {
 			shard, err := c.sharding.GetByKey(hashtag.Key(key))

ring_test.go

@@ -277,29 +277,35 @@ var _ = Describe("Redis Ring", func() {
 			var stack []string
 
 			ring.AddHook(&hook{
-				beforeProcess: func(ctx context.Context, cmd redis.Cmder) (context.Context, error) {
+				processHook: func(hook redis.ProcessHook) redis.ProcessHook {
+					return func(ctx context.Context, cmd redis.Cmder) error {
 						Expect(cmd.String()).To(Equal("ping: "))
 						stack = append(stack, "ring.BeforeProcess")
-					return ctx, nil
+
-				},
+						err := hook(ctx, cmd)
-				afterProcess: func(ctx context.Context, cmd redis.Cmder) error {
+
 						Expect(cmd.String()).To(Equal("ping: PONG"))
 						stack = append(stack, "ring.AfterProcess")
-					return nil
+
+						return err
+					}
 				},
 			})
 
 			ring.ForEachShard(ctx, func(ctx context.Context, shard *redis.Client) error {
 				shard.AddHook(&hook{
-					beforeProcess: func(ctx context.Context, cmd redis.Cmder) (context.Context, error) {
+					processHook: func(hook redis.ProcessHook) redis.ProcessHook {
+						return func(ctx context.Context, cmd redis.Cmder) error {
 							Expect(cmd.String()).To(Equal("ping: "))
 							stack = append(stack, "shard.BeforeProcess")
-						return ctx, nil
+
-					},
+							err := hook(ctx, cmd)
-					afterProcess: func(ctx context.Context, cmd redis.Cmder) error {
+
 							Expect(cmd.String()).To(Equal("ping: PONG"))
 							stack = append(stack, "shard.AfterProcess")
-						return nil
+
+							return err
+						}
 					},
 				})
 				return nil
@@ -322,33 +328,39 @@ var _ = Describe("Redis Ring", func() {
 			var stack []string
 
 			ring.AddHook(&hook{
-				beforeProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+				processPipelineHook: func(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
+					return func(ctx context.Context, cmds []redis.Cmder) error {
 						Expect(cmds).To(HaveLen(1))
 						Expect(cmds[0].String()).To(Equal("ping: "))
 						stack = append(stack, "ring.BeforeProcessPipeline")
-					return ctx, nil
+
-				},
+						err := hook(ctx, cmds)
-				afterProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) error {
+
 						Expect(cmds).To(HaveLen(1))
 						Expect(cmds[0].String()).To(Equal("ping: PONG"))
 						stack = append(stack, "ring.AfterProcessPipeline")
-					return nil
+
+						return err
+					}
 				},
 			})
 
 			ring.ForEachShard(ctx, func(ctx context.Context, shard *redis.Client) error {
 				shard.AddHook(&hook{
-					beforeProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+					processPipelineHook: func(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
+						return func(ctx context.Context, cmds []redis.Cmder) error {
 							Expect(cmds).To(HaveLen(1))
 							Expect(cmds[0].String()).To(Equal("ping: "))
 							stack = append(stack, "shard.BeforeProcessPipeline")
-						return ctx, nil
+
-					},
+							err := hook(ctx, cmds)
-					afterProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) error {
+
 							Expect(cmds).To(HaveLen(1))
 							Expect(cmds[0].String()).To(Equal("ping: PONG"))
 							stack = append(stack, "shard.AfterProcessPipeline")
-						return nil
+
+							return err
+						}
 					},
 				})
 				return nil
@@ -374,33 +386,43 @@ var _ = Describe("Redis Ring", func() {
 			var stack []string
 
 			ring.AddHook(&hook{
-				beforeProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+				processPipelineHook: func(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
-					Expect(cmds).To(HaveLen(1))
+					return func(ctx context.Context, cmds []redis.Cmder) error {
-					Expect(cmds[0].String()).To(Equal("ping: "))
+						defer GinkgoRecover()
+
+						Expect(cmds).To(HaveLen(3))
+						Expect(cmds[1].String()).To(Equal("ping: "))
 						stack = append(stack, "ring.BeforeProcessPipeline")
-					return ctx, nil
+
-				},
+						err := hook(ctx, cmds)
-				afterProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) error {
+
-					Expect(cmds).To(HaveLen(1))
+						Expect(cmds).To(HaveLen(3))
-					Expect(cmds[0].String()).To(Equal("ping: PONG"))
+						Expect(cmds[1].String()).To(Equal("ping: PONG"))
 						stack = append(stack, "ring.AfterProcessPipeline")
-					return nil
+
+						return err
+					}
 				},
 			})
 
 			ring.ForEachShard(ctx, func(ctx context.Context, shard *redis.Client) error {
 				shard.AddHook(&hook{
-					beforeProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) (context.Context, error) {
+					processPipelineHook: func(hook redis.ProcessPipelineHook) redis.ProcessPipelineHook {
+						return func(ctx context.Context, cmds []redis.Cmder) error {
+							defer GinkgoRecover()
+
 							Expect(cmds).To(HaveLen(3))
 							Expect(cmds[1].String()).To(Equal("ping: "))
 							stack = append(stack, "shard.BeforeProcessPipeline")
-						return ctx, nil
+
-					},
+							err := hook(ctx, cmds)
-					afterProcessPipeline: func(ctx context.Context, cmds []redis.Cmder) error {
+
 							Expect(cmds).To(HaveLen(3))
 							Expect(cmds[1].String()).To(Equal("ping: PONG"))
 							stack = append(stack, "shard.AfterProcessPipeline")
-						return nil
+
+							return err
+						}
 					},
 				})
 				return nil

sentinel.go

@@ -198,7 +198,17 @@ func NewFailoverClient(failoverOpt *FailoverOptions) *Client {
 	opt.Dialer = masterReplicaDialer(failover)
 	opt.init()
 
-	connPool := newConnPool(opt)
+	var connPool *pool.ConnPool
+
+	rdb := &Client{
+		baseClient: &baseClient{
+			opt: opt,
+		},
+	}
+	connPool = newConnPool(opt, rdb.baseClient.dial)
+	rdb.connPool = connPool
+	rdb.onClose = failover.Close
+	rdb.init()
 
 	failover.mu.Lock()
 	failover.onFailover = func(ctx context.Context, addr string) {
@@ -208,13 +218,7 @@ func NewFailoverClient(failoverOpt *FailoverOptions) *Client {
 	}
 	failover.mu.Unlock()
 
-	c := Client{
+	return rdb
-		baseClient: newBaseClient(opt, connPool),
-	}
-	c.cmdable = c.Process
-	c.onClose = failover.Close
-
-	return &c
 }
 
 func masterReplicaDialer(
@@ -263,14 +267,20 @@ func NewSentinelClient(opt *Options) *SentinelClient {
 	c := &SentinelClient{
 		baseClient: &baseClient{
 			opt: opt,
-			connPool: newConnPool(opt),
 		},
 	}
+	c.connPool = newConnPool(opt, c.baseClient.dial)
+
+	c.hooks.setDial(c.baseClient.dial)
+	c.hooks.setProcess(c.baseClient.process)
+
 	return c
 }
 
 func (c *SentinelClient) Process(ctx context.Context, cmd Cmder) error {
-	return c.hooks.process(ctx, cmd, c.baseClient.process)
+	err := c.hooks.process(ctx, cmd)
+	cmd.SetErr(err)
+	return err
 }
 
 func (c *SentinelClient) pubSub() *PubSub {

tx.go

@@ -37,10 +37,17 @@ func (c *Client) newTx() *Tx {
 func (c *Tx) init() {
 	c.cmdable = c.Process
 	c.statefulCmdable = c.Process
+
+	c.hooks.setDial(c.baseClient.dial)
+	c.hooks.setProcess(c.baseClient.process)
+	c.hooks.setProcessPipeline(c.baseClient.processPipeline)
+	c.hooks.setProcessTxPipeline(c.baseClient.processTxPipeline)
 }
 
 func (c *Tx) Process(ctx context.Context, cmd Cmder) error {
-	return c.hooks.process(ctx, cmd, c.baseClient.process)
+	err := c.hooks.process(ctx, cmd)
+	cmd.SetErr(err)
+	return err
 }
 
 // Watch prepares a transaction and marks the keys to be watched
@@ -93,7 +100,7 @@ func (c *Tx) Unwatch(ctx context.Context, keys ...string) *StatusCmd {
 func (c *Tx) Pipeline() Pipeliner {
 	pipe := Pipeline{
 		exec: func(ctx context.Context, cmds []Cmder) error {
-			return c.hooks.processPipeline(ctx, cmds, c.baseClient.processPipeline)
+			return c.hooks.processPipeline(ctx, cmds)
 		},
 	}
 	pipe.init()
@@ -122,9 +129,21 @@ func (c *Tx) TxPipelined(ctx context.Context, fn func(Pipeliner) error) ([]Cmder
 func (c *Tx) TxPipeline() Pipeliner {
 	pipe := Pipeline{
 		exec: func(ctx context.Context, cmds []Cmder) error {
-			return c.hooks.processTxPipeline(ctx, cmds, c.baseClient.processTxPipeline)
+			cmds = wrapMultiExec(ctx, cmds)
+			return c.hooks.processTxPipeline(ctx, cmds)
 		},
 	}
 	pipe.init()
 	return &pipe
 }
+
+func wrapMultiExec(ctx context.Context, cmds []Cmder) []Cmder {
+	if len(cmds) == 0 {
+		panic("not reached")
+	}
+	cmdsCopy := make([]Cmder, len(cmds)+2)
+	cmdsCopy[0] = NewStatusCmd(ctx, "multi")
+	copy(cmdsCopy[1:], cmds)
+	cmdsCopy[len(cmdsCopy)-1] = NewSliceCmd(ctx, "exec")
+	return cmdsCopy
+}