Issue indexer queue redis support (#6218)

* add redis queue

* finished indexer redis queue

* add redis vendor

* fix vet

* Update docs/content/doc/advanced/config-cheat-sheet.en-us.md

Co-Authored-By: lunny <xiaolunwen@gmail.com>

* switch to go mod

* Update required changes for new logging func signatures

custom/conf/app.ini.sample

@@ -264,6 +264,8 @@ ISSUE_INDEXER_QUEUE_TYPE = levelqueue
 ; When ISSUE_INDEXER_QUEUE_TYPE is levelqueue, this will be the queue will be saved path,
 ; default is indexers/issues.queue
 ISSUE_INDEXER_QUEUE_DIR = indexers/issues.queue
+; When `ISSUE_INDEXER_QUEUE_TYPE` is `redis`, this will store the redis connection string.
+ISSUE_INDEXER_QUEUE_CONN_STR = "addrs=127.0.0.1:6379 db=0"
 ; Batch queue number, default is 20
 ISSUE_INDEXER_QUEUE_BATCH_NUMBER = 20
 

docs/content/doc/advanced/config-cheat-sheet.en-us.md

@@ -158,9 +158,10 @@ Values containing `#` or `;` must be quoted using `` ` `` or `"""`.
 
 - `ISSUE_INDEXER_TYPE`: **bleve**: Issue indexer type, currently support: bleve or db, if it's db, below issue indexer item will be invalid.
 - `ISSUE_INDEXER_PATH`: **indexers/issues.bleve**: Index file used for issue search.
-- `ISSUE_INDEXER_QUEUE_TYPE`: **levelqueue**: Issue indexer queue, currently support: channel or levelqueue
-- `ISSUE_INDEXER_QUEUE_DIR`: **indexers/issues.queue**: When ISSUE_INDEXER_QUEUE_TYPE is levelqueue, this will be the queue will be saved path
-- `ISSUE_INDEXER_QUEUE_BATCH_NUMBER`: **20**: Batch queue number
+- `ISSUE_INDEXER_QUEUE_TYPE`: **levelqueue**: Issue indexer queue, currently supports:`channel`, `levelqueue`, `redis`.
+- `ISSUE_INDEXER_QUEUE_DIR`: **indexers/issues.queue**: When `ISSUE_INDEXER_QUEUE_TYPE` is `levelqueue`, this will be the queue will be saved path.
+- `ISSUE_INDEXER_QUEUE_CONN_STR`: **addrs=127.0.0.1:6379 db=0**: When `ISSUE_INDEXER_QUEUE_TYPE` is `redis`, this will store the redis connection string.
+- `ISSUE_INDEXER_QUEUE_BATCH_NUMBER`: **20**: Batch queue number.
 
 - `REPO_INDEXER_ENABLED`: **false**: Enables code search (uses a lot of disk space, about 6 times more than the repository size).
 - `REPO_INDEXER_PATH`: **indexers/repos.bleve**: Index file used for code search.

docs/content/doc/advanced/config-cheat-sheet.zh-cn.md

@@ -82,13 +82,13 @@ menu:
 - `PATH`: Tidb 或者 SQLite3 数据文件存放路径。
 - `LOG_SQL`: **true**: 显示生成的SQL，默认为真。
 
-
 ## Indexer (`indexer`)
 
 - `ISSUE_INDEXER_TYPE`: **bleve**: 工单索引类型，当前支持 `bleve` 或 `db`，当为 `db` 时其它工单索引项可不用设置。
 - `ISSUE_INDEXER_PATH`: **indexers/issues.bleve**: 工单索引文件存放路径，当索引类型为 `bleve` 时有效。
-- `ISSUE_INDEXER_QUEUE_TYPE`: **levelqueue**: 工单索引队列类型，当前支持 `channel` 或 `levelqueue`。
+- `ISSUE_INDEXER_QUEUE_TYPE`: **levelqueue**: 工单索引队列类型，当前支持 `channel`， `levelqueue` 或 `redis`。
 - `ISSUE_INDEXER_QUEUE_DIR`: **indexers/issues.queue**: 当 `ISSUE_INDEXER_QUEUE_TYPE` 为 `levelqueue` 时，保存索引队列的磁盘路径。
+- `ISSUE_INDEXER_QUEUE_CONN_STR`: **addrs=127.0.0.1:6379 db=0**: 当 `ISSUE_INDEXER_QUEUE_TYPE` 为 `redis` 时，保存Redis队列的连接字符串。
 - `ISSUE_INDEXER_QUEUE_BATCH_NUMBER`: **20**: 队列处理中批量提交数量。
 
 - `REPO_INDEXER_ENABLED`: **false**: 是否启用代码搜索（启用后会占用比较大的磁盘空间）。

go.mod

@@ -54,6 +54,7 @@ require (
 	github.com/go-macaron/inject v0.0.0-20160627170012-d8a0b8677191
 	github.com/go-macaron/session v0.0.0-20190131233854-0a0a789bf193
 	github.com/go-macaron/toolbox v0.0.0-20180818072302-a77f45a7ce90
+	github.com/go-redis/redis v6.15.2+incompatible
 	github.com/go-sql-driver/mysql v1.4.0
 	github.com/go-xorm/builder v0.3.3
 	github.com/go-xorm/core v0.6.0

go.sum

@@ -116,6 +116,8 @@ github.com/go-macaron/session v0.0.0-20190131233854-0a0a789bf193 h1:z/nqwd+ql/r6
 github.com/go-macaron/session v0.0.0-20190131233854-0a0a789bf193/go.mod h1:ScEJm9Gk+ez5JJTml5WlBIqavAfuE5nF8e4Gvyz/X+A=
 github.com/go-macaron/toolbox v0.0.0-20180818072302-a77f45a7ce90 h1:3wYKrRg9IjUMfaf3H0Hh7M5Li9ge79Y7aw2yujHa2jQ=
 github.com/go-macaron/toolbox v0.0.0-20180818072302-a77f45a7ce90/go.mod h1:Ut/NmkIMGVYlEdJBzEZgWVWG5ZpYS9BLmUgXfAgi+qM=
+github.com/go-redis/redis v6.15.2+incompatible h1:9SpNVG76gr6InJGxoZ6IuuxaCOQwDAhzyXg+Bs+0Sb4=
+github.com/go-redis/redis v6.15.2+incompatible/go.mod h1:NAIEuMOZ/fxfXJIrKDQDz8wamY7mA7PouImQ2Jvg6kA=
 github.com/go-sql-driver/mysql v0.0.0-20181218123637-c45f530f8e7f h1:fbIzwEaXt5b2bl9mm+PIufKTSGKk6ZuwSSTQ7iZj7Lo=
 github.com/go-sql-driver/mysql v0.0.0-20181218123637-c45f530f8e7f/go.mod h1:zAC/RDZ24gD3HViQzih4MyKcchzm+sOG5ZlKdlhCg5w=
 github.com/go-xorm/builder v0.3.2/go.mod h1:v8mE3MFBgtL+RGFNfUnAMUqqfk/Y4W5KuwCFQIEpQLk=

modules/indexer/issues/indexer.go

@@ -46,9 +46,9 @@ type Indexer interface {
 }
 
 var (
-	// issueIndexerUpdateQueue queue of issue ids to be updated
-	issueIndexerUpdateQueue Queue
-	issueIndexer            Indexer
+	// issueIndexerQueue queue of issue ids to be updated
+	issueIndexerQueue Queue
+	issueIndexer      Indexer
 )
 
 // InitIssueIndexer initialize issue indexer, syncReindex is true then reindex until
@@ -72,27 +72,36 @@ func InitIssueIndexer(syncReindex bool) error {
 	}
 
 	if dummyQueue {
-		issueIndexerUpdateQueue = &DummyQueue{}
+		issueIndexerQueue = &DummyQueue{}
 		return nil
 	}
 
 	var err error
-	switch setting.Indexer.IssueIndexerQueueType {
+	switch setting.Indexer.IssueQueueType {
 	case setting.LevelQueueType:
-		issueIndexerUpdateQueue, err = NewLevelQueue(
+		issueIndexerQueue, err = NewLevelQueue(
 			issueIndexer,
-			setting.Indexer.IssueIndexerQueueDir,
-			setting.Indexer.IssueIndexerQueueBatchNumber)
+			setting.Indexer.IssueQueueDir,
+			setting.Indexer.IssueQueueBatchNumber)
 		if err != nil {
 			return err
 		}
 	case setting.ChannelQueueType:
-		issueIndexerUpdateQueue = NewChannelQueue(issueIndexer, setting.Indexer.IssueIndexerQueueBatchNumber)
+		issueIndexerQueue = NewChannelQueue(issueIndexer, setting.Indexer.IssueQueueBatchNumber)
+	case setting.RedisQueueType:
+		addrs, pass, idx, err := parseConnStr(setting.Indexer.IssueQueueConnStr)
+		if err != nil {
+			return err
+		}
+		issueIndexerQueue, err = NewRedisQueue(addrs, pass, idx, issueIndexer, setting.Indexer.IssueQueueBatchNumber)
+		if err != nil {
+			return err
+		}
 	default:
-		return fmt.Errorf("Unsupported indexer queue type: %v", setting.Indexer.IssueIndexerQueueType)
+		return fmt.Errorf("Unsupported indexer queue type: %v", setting.Indexer.IssueQueueType)
 	}
 
-	go issueIndexerUpdateQueue.Run()
+	go issueIndexerQueue.Run()
 
 	if populate {
 		if syncReindex {
@@ -152,7 +161,7 @@ func UpdateIssueIndexer(issue *models.Issue) {
 			comments = append(comments, comment.Content)
 		}
 	}
-	issueIndexerUpdateQueue.Push(&IndexerData{
+	issueIndexerQueue.Push(&IndexerData{
 		ID:       issue.ID,
 		RepoID:   issue.RepoID,
 		Title:    issue.Title,
@@ -174,7 +183,7 @@ func DeleteRepoIssueIndexer(repo *models.Repository) {
 		return
 	}
 
-	issueIndexerUpdateQueue.Push(&IndexerData{
+	issueIndexerQueue.Push(&IndexerData{
 		IDs:      ids,
 		IsDelete: true,
 	})

modules/indexer/issues/indexer_test.go

@@ -29,7 +29,7 @@ func TestMain(m *testing.M) {
 func TestBleveSearchIssues(t *testing.T) {
 	assert.NoError(t, models.PrepareTestDatabase())
 
-	os.RemoveAll(setting.Indexer.IssueIndexerQueueDir)
+	os.RemoveAll(setting.Indexer.IssueQueueDir)
 	os.RemoveAll(setting.Indexer.IssuePath)
 	setting.Indexer.IssueType = "bleve"
 	if err := InitIssueIndexer(true); err != nil {

modules/indexer/issues/queue_redis.go

@@ -0,0 +1,145 @@
+// Copyright 2019 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package issues
+
+import (
+	"encoding/json"
+	"errors"
+	"strconv"
+	"strings"
+	"time"
+
+	"code.gitea.io/gitea/modules/log"
+	"github.com/go-redis/redis"
+)
+
+var (
+	_ Queue = &RedisQueue{}
+)
+
+type redisClient interface {
+	RPush(key string, args ...interface{}) *redis.IntCmd
+	LPop(key string) *redis.StringCmd
+	Ping() *redis.StatusCmd
+}
+
+// RedisQueue redis queue
+type RedisQueue struct {
+	client      redisClient
+	queueName   string
+	indexer     Indexer
+	batchNumber int
+}
+
+func parseConnStr(connStr string) (addrs, password string, dbIdx int, err error) {
+	fields := strings.Fields(connStr)
+	for _, f := range fields {
+		items := strings.SplitN(f, "=", 2)
+		if len(items) < 2 {
+			continue
+		}
+		switch strings.ToLower(items[0]) {
+		case "addrs":
+			addrs = items[1]
+		case "password":
+			password = items[1]
+		case "db":
+			dbIdx, err = strconv.Atoi(items[1])
+			if err != nil {
+				return
+			}
+		}
+	}
+	return
+}
+
+// NewRedisQueue creates single redis or cluster redis queue
+func NewRedisQueue(addrs string, password string, dbIdx int, indexer Indexer, batchNumber int) (*RedisQueue, error) {
+	dbs := strings.Split(addrs, ",")
+	var queue = RedisQueue{
+		queueName:   "issue_indexer_queue",
+		indexer:     indexer,
+		batchNumber: batchNumber,
+	}
+	if len(dbs) == 0 {
+		return nil, errors.New("no redis host found")
+	} else if len(dbs) == 1 {
+		queue.client = redis.NewClient(&redis.Options{
+			Addr:     strings.TrimSpace(dbs[0]), // use default Addr
+			Password: password,                  // no password set
+			DB:       dbIdx,                     // use default DB
+		})
+	} else {
+		queue.client = redis.NewClusterClient(&redis.ClusterOptions{
+			Addrs: dbs,
+		})
+	}
+	if err := queue.client.Ping().Err(); err != nil {
+		return nil, err
+	}
+	return &queue, nil
+}
+
+// Run runs the redis queue
+func (r *RedisQueue) Run() error {
+	var i int
+	var datas = make([]*IndexerData, 0, r.batchNumber)
+	for {
+		bs, err := r.client.LPop(r.queueName).Bytes()
+		if err != nil && err != redis.Nil {
+			log.Error("LPop faile: %v", err)
+			time.Sleep(time.Millisecond * 100)
+			continue
+		}
+
+		i++
+		if len(datas) > r.batchNumber || (len(datas) > 0 && i > 3) {
+			r.indexer.Index(datas)
+			datas = make([]*IndexerData, 0, r.batchNumber)
+			i = 0
+		}
+
+		if len(bs) <= 0 {
+			time.Sleep(time.Millisecond * 100)
+			continue
+		}
+
+		var data IndexerData
+		err = json.Unmarshal(bs, &data)
+		if err != nil {
+			log.Error("Unmarshal: %v", err)
+			time.Sleep(time.Millisecond * 100)
+			continue
+		}
+
+		log.Trace("RedisQueue: task found: %#v", data)
+
+		if data.IsDelete {
+			if data.ID > 0 {
+				if err = r.indexer.Delete(data.ID); err != nil {
+					log.Error("indexer.Delete: %v", err)
+				}
+			} else if len(data.IDs) > 0 {
+				if err = r.indexer.Delete(data.IDs...); err != nil {
+					log.Error("indexer.Delete: %v", err)
+				}
+			}
+			time.Sleep(time.Millisecond * 100)
+			continue
+		}
+
+		datas = append(datas, &data)
+		time.Sleep(time.Millisecond * 100)
+	}
+}
+
+// Push implements Queue
+func (r *RedisQueue) Push(data *IndexerData) error {
+	bs, err := json.Marshal(data)
+	if err != nil {
+		return err
+	}
+	return r.client.RPush(r.queueName, bs).Err()
+}

modules/setting/indexer.go

@@ -13,26 +13,29 @@ import (
 const (
 	LevelQueueType   = "levelqueue"
 	ChannelQueueType = "channel"
+	RedisQueueType   = "redis"
 )
 
 var (
 	// Indexer settings
 	Indexer = struct {
-		IssueType                    string
-		IssuePath                    string
-		RepoIndexerEnabled           bool
-		RepoPath                     string
-		UpdateQueueLength            int
-		MaxIndexerFileSize           int64
-		IssueIndexerQueueType        string
-		IssueIndexerQueueDir         string
-		IssueIndexerQueueBatchNumber int
+		IssueType             string
+		IssuePath             string
+		RepoIndexerEnabled    bool
+		RepoPath              string
+		UpdateQueueLength     int
+		MaxIndexerFileSize    int64
+		IssueQueueType        string
+		IssueQueueDir         string
+		IssueQueueConnStr     string
+		IssueQueueBatchNumber int
 	}{
-		IssueType:                    "bleve",
-		IssuePath:                    "indexers/issues.bleve",
-		IssueIndexerQueueType:        LevelQueueType,
-		IssueIndexerQueueDir:         "indexers/issues.queue",
-		IssueIndexerQueueBatchNumber: 20,
+		IssueType:             "bleve",
+		IssuePath:             "indexers/issues.bleve",
+		IssueQueueType:        LevelQueueType,
+		IssueQueueDir:         "indexers/issues.queue",
+		IssueQueueConnStr:     "",
+		IssueQueueBatchNumber: 20,
 	}
 )
 
@@ -50,7 +53,8 @@ func newIndexerService() {
 	}
 	Indexer.UpdateQueueLength = sec.Key("UPDATE_BUFFER_LEN").MustInt(20)
 	Indexer.MaxIndexerFileSize = sec.Key("MAX_FILE_SIZE").MustInt64(1024 * 1024)
-	Indexer.IssueIndexerQueueType = sec.Key("ISSUE_INDEXER_QUEUE_TYPE").MustString(LevelQueueType)
-	Indexer.IssueIndexerQueueDir = sec.Key("ISSUE_INDEXER_QUEUE_DIR").MustString(path.Join(AppDataPath, "indexers/issues.queue"))
-	Indexer.IssueIndexerQueueBatchNumber = sec.Key("ISSUE_INDEXER_QUEUE_BATCH_NUMBER").MustInt(20)
+	Indexer.IssueQueueType = sec.Key("ISSUE_INDEXER_QUEUE_TYPE").MustString(LevelQueueType)
+	Indexer.IssueQueueDir = sec.Key("ISSUE_INDEXER_QUEUE_DIR").MustString(path.Join(AppDataPath, "indexers/issues.queue"))
+	Indexer.IssueQueueConnStr = sec.Key("ISSUE_INDEXER_QUEUE_CONN_STR").MustString(path.Join(AppDataPath, ""))
+	Indexer.IssueQueueBatchNumber = sec.Key("ISSUE_INDEXER_QUEUE_BATCH_NUMBER").MustInt(20)
 }

vendor/github.com/go-redis/redis/.gitignore

@@ -0,0 +1,2 @@
+*.rdb
+testdata/*/

vendor/github.com/go-redis/redis/.travis.yml

@@ -0,0 +1,19 @@
+sudo: false
+language: go
+
+services:
+  - redis-server
+
+go:
+  - 1.9.x
+  - 1.10.x
+  - 1.11.x
+  - tip
+
+matrix:
+  allow_failures:
+    - go: tip
+
+install:
+  - go get github.com/onsi/ginkgo
+  - go get github.com/onsi/gomega

vendor/github.com/go-redis/redis/CHANGELOG.md

@@ -0,0 +1,25 @@
+# Changelog
+
+## Unreleased
+
+- Cluster and Ring pipelines process commands for each node in its own goroutine.
+
+## 6.14
+
+- Added Options.MinIdleConns.
+- Added Options.MaxConnAge.
+- PoolStats.FreeConns is renamed to PoolStats.IdleConns.
+- Add Client.Do to simplify creating custom commands.
+- Add Cmd.String, Cmd.Int, Cmd.Int64, Cmd.Uint64, Cmd.Float64, and Cmd.Bool helpers.
+- Lower memory usage.
+
+## v6.13
+
+- Ring got new options called `HashReplicas` and `Hash`. It is recommended to set `HashReplicas = 1000` for better keys distribution between shards.
+- Cluster client was optimized to use much less memory when reloading cluster state.
+- PubSub.ReceiveMessage is re-worked to not use ReceiveTimeout so it does not lose data when timeout occurres. In most cases it is recommended to use PubSub.Channel instead.
+- Dialer.KeepAlive is set to 5 minutes by default.
+
+## v6.12
+
+- ClusterClient got new option called `ClusterSlots` which allows to build cluster of normal Redis Servers that don't have cluster mode enabled. See https://godoc.org/github.com/go-redis/redis#example-NewClusterClient--ManualSetup

vendor/github.com/go-redis/redis/LICENSE

@@ -0,0 +1,25 @@
+Copyright (c) 2013 The github.com/go-redis/redis Authors.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/go-redis/redis/Makefile

@@ -0,0 +1,22 @@
+all: testdeps
+	go test ./...
+	go test ./... -short -race
+	env GOOS=linux GOARCH=386 go test ./...
+	go vet
+	go get github.com/gordonklaus/ineffassign
+	ineffassign .
+
+testdeps: testdata/redis/src/redis-server
+
+bench: testdeps
+	go test ./... -test.run=NONE -test.bench=. -test.benchmem
+
+.PHONY: all test testdeps bench
+
+testdata/redis:
+	mkdir -p $@
+	wget -qO- https://github.com/antirez/redis/archive/5.0.tar.gz | tar xvz --strip-components=1 -C $@
+
+testdata/redis/src/redis-server: testdata/redis
+	sed -i.bak 's/libjemalloc.a/libjemalloc.a -lrt/g' $</src/Makefile
+	cd $< && make all

vendor/github.com/go-redis/redis/README.md

@@ -0,0 +1,146 @@
+# Redis client for Golang
+
+[![Build Status](https://travis-ci.org/go-redis/redis.png?branch=master)](https://travis-ci.org/go-redis/redis)
+[![GoDoc](https://godoc.org/github.com/go-redis/redis?status.svg)](https://godoc.org/github.com/go-redis/redis)
+[![Airbrake](https://img.shields.io/badge/kudos-airbrake.io-orange.svg)](https://airbrake.io)
+
+Supports:
+
+- Redis 3 commands except QUIT, MONITOR, SLOWLOG and SYNC.
+- Automatic connection pooling with [circuit breaker](https://en.wikipedia.org/wiki/Circuit_breaker_design_pattern) support.
+- [Pub/Sub](https://godoc.org/github.com/go-redis/redis#PubSub).
+- [Transactions](https://godoc.org/github.com/go-redis/redis#Multi).
+- [Pipeline](https://godoc.org/github.com/go-redis/redis#example-Client-Pipeline) and [TxPipeline](https://godoc.org/github.com/go-redis/redis#example-Client-TxPipeline).
+- [Scripting](https://godoc.org/github.com/go-redis/redis#Script).
+- [Timeouts](https://godoc.org/github.com/go-redis/redis#Options).
+- [Redis Sentinel](https://godoc.org/github.com/go-redis/redis#NewFailoverClient).
+- [Redis Cluster](https://godoc.org/github.com/go-redis/redis#NewClusterClient).
+- [Cluster of Redis Servers](https://godoc.org/github.com/go-redis/redis#example-NewClusterClient--ManualSetup) without using cluster mode and Redis Sentinel.
+- [Ring](https://godoc.org/github.com/go-redis/redis#NewRing).
+- [Instrumentation](https://godoc.org/github.com/go-redis/redis#ex-package--Instrumentation).
+- [Cache friendly](https://github.com/go-redis/cache).
+- [Rate limiting](https://github.com/go-redis/redis_rate).
+- [Distributed Locks](https://github.com/bsm/redis-lock).
+
+API docs: https://godoc.org/github.com/go-redis/redis.
+Examples: https://godoc.org/github.com/go-redis/redis#pkg-examples.
+
+## Installation
+
+Install:
+
+```shell
+go get -u github.com/go-redis/redis
+```
+
+Import:
+
+```go
+import "github.com/go-redis/redis"
+```
+
+## Quickstart
+
+```go
+func ExampleNewClient() {
+	client := redis.NewClient(&redis.Options{
+		Addr:     "localhost:6379",
+		Password: "", // no password set
+		DB:       0,  // use default DB
+	})
+
+	pong, err := client.Ping().Result()
+	fmt.Println(pong, err)
+	// Output: PONG <nil>
+}
+
+func ExampleClient() {
+	err := client.Set("key", "value", 0).Err()
+	if err != nil {
+		panic(err)
+	}
+
+	val, err := client.Get("key").Result()
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println("key", val)
+
+	val2, err := client.Get("key2").Result()
+	if err == redis.Nil {
+		fmt.Println("key2 does not exist")
+	} else if err != nil {
+		panic(err)
+	} else {
+		fmt.Println("key2", val2)
+	}
+	// Output: key value
+	// key2 does not exist
+}
+```
+
+## Howto
+
+Please go through [examples](https://godoc.org/github.com/go-redis/redis#pkg-examples) to get an idea how to use this package.
+
+## Look and feel
+
+Some corner cases:
+
+```go
+// SET key value EX 10 NX
+set, err := client.SetNX("key", "value", 10*time.Second).Result()
+
+// SORT list LIMIT 0 2 ASC
+vals, err := client.Sort("list", redis.Sort{Offset: 0, Count: 2, Order: "ASC"}).Result()
+
+// ZRANGEBYSCORE zset -inf +inf WITHSCORES LIMIT 0 2
+vals, err := client.ZRangeByScoreWithScores("zset", redis.ZRangeBy{
+	Min: "-inf",
+	Max: "+inf",
+	Offset: 0,
+	Count: 2,
+}).Result()
+
+// ZINTERSTORE out 2 zset1 zset2 WEIGHTS 2 3 AGGREGATE SUM
+vals, err := client.ZInterStore("out", redis.ZStore{Weights: []int64{2, 3}}, "zset1", "zset2").Result()
+
+// EVAL "return {KEYS[1],ARGV[1]}" 1 "key" "hello"
+vals, err := client.Eval("return {KEYS[1],ARGV[1]}", []string{"key"}, "hello").Result()
+```
+
+## Benchmark
+
+go-redis vs redigo:
+
+```
+BenchmarkSetGoRedis10Conns64Bytes-4 	  200000	      7621 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis100Conns64Bytes-4	  200000	      7554 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis10Conns1KB-4     	  200000	      7697 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis100Conns1KB-4    	  200000	      7688 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis10Conns10KB-4    	  200000	      9214 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis100Conns10KB-4   	  200000	      9181 ns/op	     210 B/op	       6 allocs/op
+BenchmarkSetGoRedis10Conns1MB-4     	    2000	    583242 ns/op	    2337 B/op	       6 allocs/op
+BenchmarkSetGoRedis100Conns1MB-4    	    2000	    583089 ns/op	    2338 B/op	       6 allocs/op
+BenchmarkSetRedigo10Conns64Bytes-4  	  200000	      7576 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo100Conns64Bytes-4 	  200000	      7782 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo10Conns1KB-4      	  200000	      7958 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo100Conns1KB-4     	  200000	      7725 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo10Conns10KB-4     	  100000	     18442 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo100Conns10KB-4    	  100000	     18818 ns/op	     208 B/op	       7 allocs/op
+BenchmarkSetRedigo10Conns1MB-4      	    2000	    668829 ns/op	     226 B/op	       7 allocs/op
+BenchmarkSetRedigo100Conns1MB-4     	    2000	    679542 ns/op	     226 B/op	       7 allocs/op
+```
+
+Redis Cluster:
+
+```
+BenchmarkRedisPing-4                	  200000	      6983 ns/op	     116 B/op	       4 allocs/op
+BenchmarkRedisClusterPing-4         	  100000	     11535 ns/op	     117 B/op	       4 allocs/op
+```
+
+## See also
+
+- [Golang PostgreSQL ORM](https://github.com/go-pg/pg)
+- [Golang msgpack](https://github.com/vmihailenco/msgpack)
+- [Golang message task queue](https://github.com/go-msgqueue/msgqueue)

vendor/github.com/go-redis/redis/cluster_commands.go

@@ -0,0 +1,22 @@
+package redis
+
+import "sync/atomic"
+
+func (c *ClusterClient) DBSize() *IntCmd {
+	cmd := NewIntCmd("dbsize")
+	var size int64
+	err := c.ForEachMaster(func(master *Client) error {
+		n, err := master.DBSize().Result()
+		if err != nil {
+			return err
+		}
+		atomic.AddInt64(&size, n)
+		return nil
+	})
+	if err != nil {
+		cmd.setErr(err)
+		return cmd
+	}
+	cmd.val = size
+	return cmd
+}

vendor/github.com/go-redis/redis/doc.go

@@ -0,0 +1,4 @@
+/*
+Package redis implements a Redis client.
+*/
+package redis

vendor/github.com/go-redis/redis/internal/consistenthash/consistenthash.go

@@ -0,0 +1,81 @@
+/*
+Copyright 2013 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package consistenthash provides an implementation of a ring hash.
+package consistenthash
+
+import (
+	"hash/crc32"
+	"sort"
+	"strconv"
+)
+
+type Hash func(data []byte) uint32
+
+type Map struct {
+	hash     Hash
+	replicas int
+	keys     []int // Sorted
+	hashMap  map[int]string
+}
+
+func New(replicas int, fn Hash) *Map {
+	m := &Map{
+		replicas: replicas,
+		hash:     fn,
+		hashMap:  make(map[int]string),
+	}
+	if m.hash == nil {
+		m.hash = crc32.ChecksumIEEE
+	}
+	return m
+}
+
+// Returns true if there are no items available.
+func (m *Map) IsEmpty() bool {
+	return len(m.keys) == 0
+}
+
+// Adds some keys to the hash.
+func (m *Map) Add(keys ...string) {
+	for _, key := range keys {
+		for i := 0; i < m.replicas; i++ {
+			hash := int(m.hash([]byte(strconv.Itoa(i) + key)))
+			m.keys = append(m.keys, hash)
+			m.hashMap[hash] = key
+		}
+	}
+	sort.Ints(m.keys)
+}
+
+// Gets the closest item in the hash to the provided key.
+func (m *Map) Get(key string) string {
+	if m.IsEmpty() {
+		return ""
+	}
+
+	hash := int(m.hash([]byte(key)))
+
+	// Binary search for appropriate replica.
+	idx := sort.Search(len(m.keys), func(i int) bool { return m.keys[i] >= hash })
+
+	// Means we have cycled back to the first replica.
+	if idx == len(m.keys) {
+		idx = 0
+	}
+
+	return m.hashMap[m.keys[idx]]
+}

vendor/github.com/go-redis/redis/internal/error.go

@@ -0,0 +1,89 @@
+package internal
+
+import (
+	"io"
+	"net"
+	"strings"
+
+	"github.com/go-redis/redis/internal/proto"
+)
+
+func IsRetryableError(err error, retryTimeout bool) bool {
+	if err == nil {
+		return false
+	}
+	if err == io.EOF {
+		return true
+	}
+	if netErr, ok := err.(net.Error); ok {
+		if netErr.Timeout() {
+			return retryTimeout
+		}
+		return true
+	}
+	s := err.Error()
+	if s == "ERR max number of clients reached" {
+		return true
+	}
+	if strings.HasPrefix(s, "LOADING ") {
+		return true
+	}
+	if strings.HasPrefix(s, "READONLY ") {
+		return true
+	}
+	if strings.HasPrefix(s, "CLUSTERDOWN ") {
+		return true
+	}
+	return false
+}
+
+func IsRedisError(err error) bool {
+	_, ok := err.(proto.RedisError)
+	return ok
+}
+
+func IsBadConn(err error, allowTimeout bool) bool {
+	if err == nil {
+		return false
+	}
+	if IsRedisError(err) {
+		// #790
+		return IsReadOnlyError(err)
+	}
+	if allowTimeout {
+		if netErr, ok := err.(net.Error); ok && netErr.Timeout() {
+			return false
+		}
+	}
+	return true
+}
+
+func IsMovedError(err error) (moved bool, ask bool, addr string) {
+	if !IsRedisError(err) {
+		return
+	}
+
+	s := err.Error()
+	if strings.HasPrefix(s, "MOVED ") {
+		moved = true
+	} else if strings.HasPrefix(s, "ASK ") {
+		ask = true
+	} else {
+		return
+	}
+
+	ind := strings.LastIndex(s, " ")
+	if ind == -1 {
+		return false, false, ""
+	}
+	addr = s[ind+1:]
+	return
+}
+
+func IsLoadingError(err error) bool {
+	return strings.HasPrefix(err.Error(), "LOADING ")
+}
+
+func IsReadOnlyError(err error) bool {
+	return strings.HasPrefix(err.Error(), "READONLY ")
+}

vendor/github.com/go-redis/redis/internal/hashtag/hashtag.go

@@ -0,0 +1,77 @@
+package hashtag
+
+import (
+	"math/rand"
+	"strings"
+)
+
+const slotNumber = 16384
+
+// CRC16 implementation according to CCITT standards.
+// Copyright 2001-2010 Georges Menie (www.menie.org)
+// Copyright 2013 The Go Authors. All rights reserved.
+// http://redis.io/topics/cluster-spec#appendix-a-crc16-reference-implementation-in-ansi-c
+var crc16tab = [256]uint16{
+	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
+	0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
+	0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
+	0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
+	0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
+	0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
+	0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
+	0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
+	0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
+	0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
+	0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
+	0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
+	0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
+	0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
+	0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
+	0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
+	0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
+	0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
+	0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
+	0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
+	0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
+	0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
+	0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
+	0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
+	0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
+	0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
+	0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
+	0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
+	0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
+	0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
+	0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
+	0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0,
+}
+
+func Key(key string) string {
+	if s := strings.IndexByte(key, '{'); s > -1 {
+		if e := strings.IndexByte(key[s+1:], '}'); e > 0 {
+			return key[s+1 : s+e+1]
+		}
+	}
+	return key
+}
+
+func RandomSlot() int {
+	return rand.Intn(slotNumber)
+}
+
+// hashSlot returns a consistent slot number between 0 and 16383
+// for any given string key.
+func Slot(key string) int {
+	if key == "" {
+		return RandomSlot()
+	}
+	key = Key(key)
+	return int(crc16sum(key)) % slotNumber
+}
+
+func crc16sum(key string) (crc uint16) {
+	for i := 0; i < len(key); i++ {
+		crc = (crc << 8) ^ crc16tab[(byte(crc>>8)^key[i])&0x00ff]
+	}
+	return
+}

vendor/github.com/go-redis/redis/internal/internal.go

@@ -0,0 +1,24 @@
+package internal
+
+import (
+	"math/rand"
+	"time"
+)
+
+// Retry backoff with jitter sleep to prevent overloaded conditions during intervals
+// https://www.awsarchitectureblog.com/2015/03/backoff.html
+func RetryBackoff(retry int, minBackoff, maxBackoff time.Duration) time.Duration {
+	if retry < 0 {
+		retry = 0
+	}
+
+	backoff := minBackoff << uint(retry)
+	if backoff > maxBackoff || backoff < minBackoff {
+		backoff = maxBackoff
+	}
+
+	if backoff == 0 {
+		return 0
+	}
+	return time.Duration(rand.Int63n(int64(backoff)))
+}

vendor/github.com/go-redis/redis/internal/log.go

@@ -0,0 +1,15 @@
+package internal
+
+import (
+	"fmt"
+	"log"
+)
+
+var Logger *log.Logger
+
+func Logf(s string, args ...interface{}) {
+	if Logger == nil {
+		return
+	}
+	Logger.Output(2, fmt.Sprintf(s, args...))
+}

vendor/github.com/go-redis/redis/internal/once.go

@@ -0,0 +1,60 @@
+/*
+Copyright 2014 The Camlistore Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package internal
+
+import (
+	"sync"
+	"sync/atomic"
+)
+
+// A Once will perform a successful action exactly once.
+//
+// Unlike a sync.Once, this Once's func returns an error
+// and is re-armed on failure.
+type Once struct {
+	m    sync.Mutex
+	done uint32
+}
+
+// Do calls the function f if and only if Do has not been invoked
+// without error for this instance of Once.  In other words, given
+// 	var once Once
+// if once.Do(f) is called multiple times, only the first call will
+// invoke f, even if f has a different value in each invocation unless
+// f returns an error.  A new instance of Once is required for each
+// function to execute.
+//
+// Do is intended for initialization that must be run exactly once.  Since f
+// is niladic, it may be necessary to use a function literal to capture the
+// arguments to a function to be invoked by Do:
+// 	err := config.once.Do(func() error { return config.init(filename) })
+func (o *Once) Do(f func() error) error {
+	if atomic.LoadUint32(&o.done) == 1 {
+		return nil
+	}
+	// Slow-path.
+	o.m.Lock()
+	defer o.m.Unlock()
+	var err error
+	if o.done == 0 {
+		err = f()
+		if err == nil {
+			atomic.StoreUint32(&o.done, 1)
+		}
+	}
+	return err
+}

vendor/github.com/go-redis/redis/internal/pool/conn.go

@@ -0,0 +1,93 @@
+package pool
+
+import (
+	"net"
+	"sync/atomic"
+	"time"
+
+	"github.com/go-redis/redis/internal/proto"
+)
+
+var noDeadline = time.Time{}
+
+type Conn struct {
+	netConn net.Conn
+
+	rd       *proto.Reader
+	rdLocked bool
+	wr       *proto.Writer
+
+	InitedAt time.Time
+	pooled   bool
+	usedAt   atomic.Value
+}
+
+func NewConn(netConn net.Conn) *Conn {
+	cn := &Conn{
+		netConn: netConn,
+	}
+	cn.rd = proto.NewReader(netConn)
+	cn.wr = proto.NewWriter(netConn)
+	cn.SetUsedAt(time.Now())
+	return cn
+}
+
+func (cn *Conn) UsedAt() time.Time {
+	return cn.usedAt.Load().(time.Time)
+}
+
+func (cn *Conn) SetUsedAt(tm time.Time) {
+	cn.usedAt.Store(tm)
+}
+
+func (cn *Conn) SetNetConn(netConn net.Conn) {
+	cn.netConn = netConn
+	cn.rd.Reset(netConn)
+	cn.wr.Reset(netConn)
+}
+
+func (cn *Conn) setReadTimeout(timeout time.Duration) error {
+	now := time.Now()
+	cn.SetUsedAt(now)
+	if timeout > 0 {
+		return cn.netConn.SetReadDeadline(now.Add(timeout))
+	}
+	return cn.netConn.SetReadDeadline(noDeadline)
+}
+
+func (cn *Conn) setWriteTimeout(timeout time.Duration) error {
+	now := time.Now()
+	cn.SetUsedAt(now)
+	if timeout > 0 {
+		return cn.netConn.SetWriteDeadline(now.Add(timeout))
+	}
+	return cn.netConn.SetWriteDeadline(noDeadline)
+}
+
+func (cn *Conn) Write(b []byte) (int, error) {
+	return cn.netConn.Write(b)
+}
+
+func (cn *Conn) RemoteAddr() net.Addr {
+	return cn.netConn.RemoteAddr()
+}
+
+func (cn *Conn) WithReader(timeout time.Duration, fn func(rd *proto.Reader) error) error {
+	_ = cn.setReadTimeout(timeout)
+	return fn(cn.rd)
+}
+
+func (cn *Conn) WithWriter(timeout time.Duration, fn func(wr *proto.Writer) error) error {
+	_ = cn.setWriteTimeout(timeout)
+
+	firstErr := fn(cn.wr)
+	err := cn.wr.Flush()
+	if err != nil && firstErr == nil {
+		firstErr = err
+	}
+	return firstErr
+}
+
+func (cn *Conn) Close() error {
+	return cn.netConn.Close()
+}

vendor/github.com/go-redis/redis/internal/pool/pool.go

@@ -0,0 +1,476 @@
+package pool
+
+import (
+	"errors"
+	"net"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/go-redis/redis/internal"
+)
+
+var ErrClosed = errors.New("redis: client is closed")
+var ErrPoolTimeout = errors.New("redis: connection pool timeout")
+
+var timers = sync.Pool{
+	New: func() interface{} {
+		t := time.NewTimer(time.Hour)
+		t.Stop()
+		return t
+	},
+}
+
+// Stats contains pool state information and accumulated stats.
+type Stats struct {
+	Hits     uint32 // number of times free connection was found in the pool
+	Misses   uint32 // number of times free connection was NOT found in the pool
+	Timeouts uint32 // number of times a wait timeout occurred
+
+	TotalConns uint32 // number of total connections in the pool
+	IdleConns  uint32 // number of idle connections in the pool
+	StaleConns uint32 // number of stale connections removed from the pool
+}
+
+type Pooler interface {
+	NewConn() (*Conn, error)
+	CloseConn(*Conn) error
+
+	Get() (*Conn, error)
+	Put(*Conn)
+	Remove(*Conn)
+
+	Len() int
+	IdleLen() int
+	Stats() *Stats
+
+	Close() error
+}
+
+type Options struct {
+	Dialer  func() (net.Conn, error)
+	OnClose func(*Conn) error
+
+	PoolSize           int
+	MinIdleConns       int
+	MaxConnAge         time.Duration
+	PoolTimeout        time.Duration
+	IdleTimeout        time.Duration
+	IdleCheckFrequency time.Duration
+}
+
+type ConnPool struct {
+	opt *Options
+
+	dialErrorsNum uint32 // atomic
+
+	lastDialErrorMu sync.RWMutex
+	lastDialError   error
+
+	queue chan struct{}
+
+	connsMu      sync.Mutex
+	conns        []*Conn
+	idleConns    []*Conn
+	poolSize     int
+	idleConnsLen int
+
+	stats Stats
+
+	_closed uint32 // atomic
+}
+
+var _ Pooler = (*ConnPool)(nil)
+
+func NewConnPool(opt *Options) *ConnPool {
+	p := &ConnPool{
+		opt: opt,
+
+		queue:     make(chan struct{}, opt.PoolSize),
+		conns:     make([]*Conn, 0, opt.PoolSize),
+		idleConns: make([]*Conn, 0, opt.PoolSize),
+	}
+
+	for i := 0; i < opt.MinIdleConns; i++ {
+		p.checkMinIdleConns()
+	}
+
+	if opt.IdleTimeout > 0 && opt.IdleCheckFrequency > 0 {
+		go p.reaper(opt.IdleCheckFrequency)
+	}
+
+	return p
+}
+
+func (p *ConnPool) checkMinIdleConns() {
+	if p.opt.MinIdleConns == 0 {
+		return
+	}
+	if p.poolSize < p.opt.PoolSize && p.idleConnsLen < p.opt.MinIdleConns {
+		p.poolSize++
+		p.idleConnsLen++
+		go p.addIdleConn()
+	}
+}
+
+func (p *ConnPool) addIdleConn() {
+	cn, err := p.newConn(true)
+	if err != nil {
+		return
+	}
+
+	p.connsMu.Lock()
+	p.conns = append(p.conns, cn)
+	p.idleConns = append(p.idleConns, cn)
+	p.connsMu.Unlock()
+}
+
+func (p *ConnPool) NewConn() (*Conn, error) {
+	return p._NewConn(false)
+}
+
+func (p *ConnPool) _NewConn(pooled bool) (*Conn, error) {
+	cn, err := p.newConn(pooled)
+	if err != nil {
+		return nil, err
+	}
+
+	p.connsMu.Lock()
+	p.conns = append(p.conns, cn)
+	if pooled {
+		if p.poolSize < p.opt.PoolSize {
+			p.poolSize++
+		} else {
+			cn.pooled = false
+		}
+	}
+	p.connsMu.Unlock()
+	return cn, nil
+}
+
+func (p *ConnPool) newConn(pooled bool) (*Conn, error) {
+	if p.closed() {
+		return nil, ErrClosed
+	}
+
+	if atomic.LoadUint32(&p.dialErrorsNum) >= uint32(p.opt.PoolSize) {
+		return nil, p.getLastDialError()
+	}
+
+	netConn, err := p.opt.Dialer()
+	if err != nil {
+		p.setLastDialError(err)
+		if atomic.AddUint32(&p.dialErrorsNum, 1) == uint32(p.opt.PoolSize) {
+			go p.tryDial()
+		}
+		return nil, err
+	}
+
+	cn := NewConn(netConn)
+	cn.pooled = pooled
+	return cn, nil
+}
+
+func (p *ConnPool) tryDial() {
+	for {
+		if p.closed() {
+			return
+		}
+
+		conn, err := p.opt.Dialer()
+		if err != nil {
+			p.setLastDialError(err)
+			time.Sleep(time.Second)
+			continue
+		}
+
+		atomic.StoreUint32(&p.dialErrorsNum, 0)
+		_ = conn.Close()
+		return
+	}
+}
+
+func (p *ConnPool) setLastDialError(err error) {
+	p.lastDialErrorMu.Lock()
+	p.lastDialError = err
+	p.lastDialErrorMu.Unlock()
+}
+
+func (p *ConnPool) getLastDialError() error {
+	p.lastDialErrorMu.RLock()
+	err := p.lastDialError
+	p.lastDialErrorMu.RUnlock()
+	return err
+}
+
+// Get returns existed connection from the pool or creates a new one.
+func (p *ConnPool) Get() (*Conn, error) {
+	if p.closed() {
+		return nil, ErrClosed
+	}
+
+	err := p.waitTurn()
+	if err != nil {
+		return nil, err
+	}
+
+	for {
+		p.connsMu.Lock()
+		cn := p.popIdle()
+		p.connsMu.Unlock()
+
+		if cn == nil {
+			break
+		}
+
+		if p.isStaleConn(cn) {
+			_ = p.CloseConn(cn)
+			continue
+		}
+
+		atomic.AddUint32(&p.stats.Hits, 1)
+		return cn, nil
+	}
+
+	atomic.AddUint32(&p.stats.Misses, 1)
+
+	newcn, err := p._NewConn(true)
+	if err != nil {
+		p.freeTurn()
+		return nil, err
+	}
+
+	return newcn, nil
+}
+
+func (p *ConnPool) getTurn() {
+	p.queue <- struct{}{}
+}
+
+func (p *ConnPool) waitTurn() error {
+	select {
+	case p.queue <- struct{}{}:
+		return nil
+	default:
+		timer := timers.Get().(*time.Timer)
+		timer.Reset(p.opt.PoolTimeout)
+
+		select {
+		case p.queue <- struct{}{}:
+			if !timer.Stop() {
+				<-timer.C
+			}
+			timers.Put(timer)
+			return nil
+		case <-timer.C:
+			timers.Put(timer)
+			atomic.AddUint32(&p.stats.Timeouts, 1)
+			return ErrPoolTimeout
+		}
+	}
+}
+
+func (p *ConnPool) freeTurn() {
+	<-p.queue
+}
+
+func (p *ConnPool) popIdle() *Conn {
+	if len(p.idleConns) == 0 {
+		return nil
+	}
+
+	idx := len(p.idleConns) - 1
+	cn := p.idleConns[idx]
+	p.idleConns = p.idleConns[:idx]
+	p.idleConnsLen--
+	p.checkMinIdleConns()
+	return cn
+}
+
+func (p *ConnPool) Put(cn *Conn) {
+	if !cn.pooled {
+		p.Remove(cn)
+		return
+	}
+
+	p.connsMu.Lock()
+	p.idleConns = append(p.idleConns, cn)
+	p.idleConnsLen++
+	p.connsMu.Unlock()
+	p.freeTurn()
+}
+
+func (p *ConnPool) Remove(cn *Conn) {
+	p.removeConn(cn)
+	p.freeTurn()
+	_ = p.closeConn(cn)
+}
+
+func (p *ConnPool) CloseConn(cn *Conn) error {
+	p.removeConn(cn)
+	return p.closeConn(cn)
+}
+
+func (p *ConnPool) removeConn(cn *Conn) {
+	p.connsMu.Lock()
+	for i, c := range p.conns {
+		if c == cn {
+			p.conns = append(p.conns[:i], p.conns[i+1:]...)
+			if cn.pooled {
+				p.poolSize--
+				p.checkMinIdleConns()
+			}
+			break
+		}
+	}
+	p.connsMu.Unlock()
+}
+
+func (p *ConnPool) closeConn(cn *Conn) error {
+	if p.opt.OnClose != nil {
+		_ = p.opt.OnClose(cn)
+	}
+	return cn.Close()
+}
+
+// Len returns total number of connections.
+func (p *ConnPool) Len() int {
+	p.connsMu.Lock()
+	n := len(p.conns)
+	p.connsMu.Unlock()
+	return n
+}
+
+// IdleLen returns number of idle connections.
+func (p *ConnPool) IdleLen() int {
+	p.connsMu.Lock()
+	n := p.idleConnsLen
+	p.connsMu.Unlock()
+	return n
+}
+
+func (p *ConnPool) Stats() *Stats {
+	idleLen := p.IdleLen()
+	return &Stats{
+		Hits:     atomic.LoadUint32(&p.stats.Hits),
+		Misses:   atomic.LoadUint32(&p.stats.Misses),
+		Timeouts: atomic.LoadUint32(&p.stats.Timeouts),
+
+		TotalConns: uint32(p.Len()),
+		IdleConns:  uint32(idleLen),
+		StaleConns: atomic.LoadUint32(&p.stats.StaleConns),
+	}
+}
+
+func (p *ConnPool) closed() bool {
+	return atomic.LoadUint32(&p._closed) == 1
+}
+
+func (p *ConnPool) Filter(fn func(*Conn) bool) error {
+	var firstErr error
+	p.connsMu.Lock()
+	for _, cn := range p.conns {
+		if fn(cn) {
+			if err := p.closeConn(cn); err != nil && firstErr == nil {
+				firstErr = err
+			}
+		}
+	}
+	p.connsMu.Unlock()
+	return firstErr
+}
+
+func (p *ConnPool) Close() error {
+	if !atomic.CompareAndSwapUint32(&p._closed, 0, 1) {
+		return ErrClosed
+	}
+
+	var firstErr error
+	p.connsMu.Lock()
+	for _, cn := range p.conns {
+		if err := p.closeConn(cn); err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+	p.conns = nil
+	p.poolSize = 0
+	p.idleConns = nil
+	p.idleConnsLen = 0
+	p.connsMu.Unlock()
+
+	return firstErr
+}
+
+func (p *ConnPool) reapStaleConn() *Conn {
+	if len(p.idleConns) == 0 {
+		return nil
+	}
+
+	cn := p.idleConns[0]
+	if !p.isStaleConn(cn) {
+		return nil
+	}
+
+	p.idleConns = append(p.idleConns[:0], p.idleConns[1:]...)
+	p.idleConnsLen--
+
+	return cn
+}
+
+func (p *ConnPool) ReapStaleConns() (int, error) {
+	var n int
+	for {
+		p.getTurn()
+
+		p.connsMu.Lock()
+		cn := p.reapStaleConn()
+		p.connsMu.Unlock()
+
+		if cn != nil {
+			p.removeConn(cn)
+		}
+
+		p.freeTurn()
+
+		if cn != nil {
+			p.closeConn(cn)
+			n++
+		} else {
+			break
+		}
+	}
+	return n, nil
+}
+
+func (p *ConnPool) reaper(frequency time.Duration) {
+	ticker := time.NewTicker(frequency)
+	defer ticker.Stop()
+
+	for range ticker.C {
+		if p.closed() {
+			break
+		}
+		n, err := p.ReapStaleConns()
+		if err != nil {
+			internal.Logf("ReapStaleConns failed: %s", err)
+			continue
+		}
+		atomic.AddUint32(&p.stats.StaleConns, uint32(n))
+	}
+}
+
+func (p *ConnPool) isStaleConn(cn *Conn) bool {
+	if p.opt.IdleTimeout == 0 && p.opt.MaxConnAge == 0 {
+		return false
+	}
+
+	now := time.Now()
+	if p.opt.IdleTimeout > 0 && now.Sub(cn.UsedAt()) >= p.opt.IdleTimeout {
+		return true
+	}
+	if p.opt.MaxConnAge > 0 && now.Sub(cn.InitedAt) >= p.opt.MaxConnAge {
+		return true
+	}
+
+	return false
+}

vendor/github.com/go-redis/redis/internal/pool/pool_single.go

@@ -0,0 +1,53 @@
+package pool
+
+type SingleConnPool struct {
+	cn *Conn
+}
+
+var _ Pooler = (*SingleConnPool)(nil)
+
+func NewSingleConnPool(cn *Conn) *SingleConnPool {
+	return &SingleConnPool{
+		cn: cn,
+	}
+}
+
+func (p *SingleConnPool) NewConn() (*Conn, error) {
+	panic("not implemented")
+}
+
+func (p *SingleConnPool) CloseConn(*Conn) error {
+	panic("not implemented")
+}
+
+func (p *SingleConnPool) Get() (*Conn, error) {
+	return p.cn, nil
+}
+
+func (p *SingleConnPool) Put(cn *Conn) {
+	if p.cn != cn {
+		panic("p.cn != cn")
+	}
+}
+
+func (p *SingleConnPool) Remove(cn *Conn) {
+	if p.cn != cn {
+		panic("p.cn != cn")
+	}
+}
+
+func (p *SingleConnPool) Len() int {
+	return 1
+}
+
+func (p *SingleConnPool) IdleLen() int {
+	return 0
+}
+
+func (p *SingleConnPool) Stats() *Stats {
+	return nil
+}
+
+func (p *SingleConnPool) Close() error {
+	return nil
+}

vendor/github.com/go-redis/redis/internal/pool/pool_sticky.go

@@ -0,0 +1,109 @@
+package pool
+
+import "sync"
+
+type StickyConnPool struct {
+	pool     *ConnPool
+	reusable bool
+
+	cn     *Conn
+	closed bool
+	mu     sync.Mutex
+}
+
+var _ Pooler = (*StickyConnPool)(nil)
+
+func NewStickyConnPool(pool *ConnPool, reusable bool) *StickyConnPool {
+	return &StickyConnPool{
+		pool:     pool,
+		reusable: reusable,
+	}
+}
+
+func (p *StickyConnPool) NewConn() (*Conn, error) {
+	panic("not implemented")
+}
+
+func (p *StickyConnPool) CloseConn(*Conn) error {
+	panic("not implemented")
+}
+
+func (p *StickyConnPool) Get() (*Conn, error) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	if p.closed {
+		return nil, ErrClosed
+	}
+	if p.cn != nil {
+		return p.cn, nil
+	}
+
+	cn, err := p.pool.Get()
+	if err != nil {
+		return nil, err
+	}
+
+	p.cn = cn
+	return cn, nil
+}
+
+func (p *StickyConnPool) putUpstream() {
+	p.pool.Put(p.cn)
+	p.cn = nil
+}
+
+func (p *StickyConnPool) Put(cn *Conn) {}
+
+func (p *StickyConnPool) removeUpstream() {
+	p.pool.Remove(p.cn)
+	p.cn = nil
+}
+
+func (p *StickyConnPool) Remove(cn *Conn) {
+	p.removeUpstream()
+}
+
+func (p *StickyConnPool) Len() int {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	if p.cn == nil {
+		return 0
+	}
+	return 1
+}
+
+func (p *StickyConnPool) IdleLen() int {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	if p.cn == nil {
+		return 1
+	}
+	return 0
+}
+
+func (p *StickyConnPool) Stats() *Stats {
+	return nil
+}
+
+func (p *StickyConnPool) Close() error {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	if p.closed {
+		return ErrClosed
+	}
+	p.closed = true
+
+	if p.cn != nil {
+		if p.reusable {
+			p.putUpstream()
+		} else {
+			p.removeUpstream()
+		}
+	}
+
+	return nil
+}

vendor/github.com/go-redis/redis/internal/proto/reader.go

@@ -0,0 +1,290 @@
+package proto
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strconv"
+
+	"github.com/go-redis/redis/internal/util"
+)
+
+const (
+	ErrorReply  = '-'
+	StatusReply = '+'
+	IntReply    = ':'
+	StringReply = '$'
+	ArrayReply  = '*'
+)
+
+//------------------------------------------------------------------------------
+
+const Nil = RedisError("redis: nil")
+
+type RedisError string
+
+func (e RedisError) Error() string { return string(e) }
+
+//------------------------------------------------------------------------------
+
+type MultiBulkParse func(*Reader, int64) (interface{}, error)
+
+type Reader struct {
+	rd   *bufio.Reader
+	_buf []byte
+}
+
+func NewReader(rd io.Reader) *Reader {
+	return &Reader{
+		rd:   bufio.NewReader(rd),
+		_buf: make([]byte, 64),
+	}
+}
+
+func (r *Reader) Reset(rd io.Reader) {
+	r.rd.Reset(rd)
+}
+
+func (r *Reader) ReadLine() ([]byte, error) {
+	line, isPrefix, err := r.rd.ReadLine()
+	if err != nil {
+		return nil, err
+	}
+	if isPrefix {
+		return nil, bufio.ErrBufferFull
+	}
+	if len(line) == 0 {
+		return nil, fmt.Errorf("redis: reply is empty")
+	}
+	if isNilReply(line) {
+		return nil, Nil
+	}
+	return line, nil
+}
+
+func (r *Reader) ReadReply(m MultiBulkParse) (interface{}, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return nil, err
+	}
+
+	switch line[0] {
+	case ErrorReply:
+		return nil, ParseErrorReply(line)
+	case StatusReply:
+		return string(line[1:]), nil
+	case IntReply:
+		return util.ParseInt(line[1:], 10, 64)
+	case StringReply:
+		return r.readStringReply(line)
+	case ArrayReply:
+		n, err := parseArrayLen(line)
+		if err != nil {
+			return nil, err
+		}
+		return m(r, n)
+	}
+	return nil, fmt.Errorf("redis: can't parse %.100q", line)
+}
+
+func (r *Reader) ReadIntReply() (int64, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return 0, err
+	}
+	switch line[0] {
+	case ErrorReply:
+		return 0, ParseErrorReply(line)
+	case IntReply:
+		return util.ParseInt(line[1:], 10, 64)
+	default:
+		return 0, fmt.Errorf("redis: can't parse int reply: %.100q", line)
+	}
+}
+
+func (r *Reader) ReadString() (string, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return "", err
+	}
+	switch line[0] {
+	case ErrorReply:
+		return "", ParseErrorReply(line)
+	case StringReply:
+		return r.readStringReply(line)
+	case StatusReply:
+		return string(line[1:]), nil
+	case IntReply:
+		return string(line[1:]), nil
+	default:
+		return "", fmt.Errorf("redis: can't parse reply=%.100q reading string", line)
+	}
+}
+
+func (r *Reader) readStringReply(line []byte) (string, error) {
+	if isNilReply(line) {
+		return "", Nil
+	}
+
+	replyLen, err := strconv.Atoi(string(line[1:]))
+	if err != nil {
+		return "", err
+	}
+
+	b := make([]byte, replyLen+2)
+	_, err = io.ReadFull(r.rd, b)
+	if err != nil {
+		return "", err
+	}
+
+	return util.BytesToString(b[:replyLen]), nil
+}
+
+func (r *Reader) ReadArrayReply(m MultiBulkParse) (interface{}, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return nil, err
+	}
+	switch line[0] {
+	case ErrorReply:
+		return nil, ParseErrorReply(line)
+	case ArrayReply:
+		n, err := parseArrayLen(line)
+		if err != nil {
+			return nil, err
+		}
+		return m(r, n)
+	default:
+		return nil, fmt.Errorf("redis: can't parse array reply: %.100q", line)
+	}
+}
+
+func (r *Reader) ReadArrayLen() (int64, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return 0, err
+	}
+	switch line[0] {
+	case ErrorReply:
+		return 0, ParseErrorReply(line)
+	case ArrayReply:
+		return parseArrayLen(line)
+	default:
+		return 0, fmt.Errorf("redis: can't parse array reply: %.100q", line)
+	}
+}
+
+func (r *Reader) ReadScanReply() ([]string, uint64, error) {
+	n, err := r.ReadArrayLen()
+	if err != nil {
+		return nil, 0, err
+	}
+	if n != 2 {
+		return nil, 0, fmt.Errorf("redis: got %d elements in scan reply, expected 2", n)
+	}
+
+	cursor, err := r.ReadUint()
+	if err != nil {
+		return nil, 0, err
+	}
+
+	n, err = r.ReadArrayLen()
+	if err != nil {
+		return nil, 0, err
+	}
+
+	keys := make([]string, n)
+	for i := int64(0); i < n; i++ {
+		key, err := r.ReadString()
+		if err != nil {
+			return nil, 0, err
+		}
+		keys[i] = key
+	}
+
+	return keys, cursor, err
+}
+
+func (r *Reader) ReadInt() (int64, error) {
+	b, err := r.readTmpBytesReply()
+	if err != nil {
+		return 0, err
+	}
+	return util.ParseInt(b, 10, 64)
+}
+
+func (r *Reader) ReadUint() (uint64, error) {
+	b, err := r.readTmpBytesReply()
+	if err != nil {
+		return 0, err
+	}
+	return util.ParseUint(b, 10, 64)
+}
+
+func (r *Reader) ReadFloatReply() (float64, error) {
+	b, err := r.readTmpBytesReply()
+	if err != nil {
+		return 0, err
+	}
+	return util.ParseFloat(b, 64)
+}
+
+func (r *Reader) readTmpBytesReply() ([]byte, error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return nil, err
+	}
+	switch line[0] {
+	case ErrorReply:
+		return nil, ParseErrorReply(line)
+	case StringReply:
+		return r._readTmpBytesReply(line)
+	case StatusReply:
+		return line[1:], nil
+	default:
+		return nil, fmt.Errorf("redis: can't parse string reply: %.100q", line)
+	}
+}
+
+func (r *Reader) _readTmpBytesReply(line []byte) ([]byte, error) {
+	if isNilReply(line) {
+		return nil, Nil
+	}
+
+	replyLen, err := strconv.Atoi(string(line[1:]))
+	if err != nil {
+		return nil, err
+	}
+
+	buf := r.buf(replyLen + 2)
+	_, err = io.ReadFull(r.rd, buf)
+	if err != nil {
+		return nil, err
+	}
+
+	return buf[:replyLen], nil
+}
+
+func (r *Reader) buf(n int) []byte {
+	if d := n - cap(r._buf); d > 0 {
+		r._buf = append(r._buf, make([]byte, d)...)
+	}
+	return r._buf[:n]
+}
+
+func isNilReply(b []byte) bool {
+	return len(b) == 3 &&
+		(b[0] == StringReply || b[0] == ArrayReply) &&
+		b[1] == '-' && b[2] == '1'
+}
+
+func ParseErrorReply(line []byte) error {
+	return RedisError(string(line[1:]))
+}
+
+func parseArrayLen(line []byte) (int64, error) {
+	if isNilReply(line) {
+		return 0, Nil
+	}
+	return util.ParseInt(line[1:], 10, 64)
+}

vendor/github.com/go-redis/redis/internal/proto/scan.go

@@ -0,0 +1,166 @@
+package proto
+
+import (
+	"encoding"
+	"fmt"
+	"reflect"
+
+	"github.com/go-redis/redis/internal/util"
+)
+
+func Scan(b []byte, v interface{}) error {
+	switch v := v.(type) {
+	case nil:
+		return fmt.Errorf("redis: Scan(nil)")
+	case *string:
+		*v = util.BytesToString(b)
+		return nil
+	case *[]byte:
+		*v = b
+		return nil
+	case *int:
+		var err error
+		*v, err = util.Atoi(b)
+		return err
+	case *int8:
+		n, err := util.ParseInt(b, 10, 8)
+		if err != nil {
+			return err
+		}
+		*v = int8(n)
+		return nil
+	case *int16:
+		n, err := util.ParseInt(b, 10, 16)
+		if err != nil {
+			return err
+		}
+		*v = int16(n)
+		return nil
+	case *int32:
+		n, err := util.ParseInt(b, 10, 32)
+		if err != nil {
+			return err
+		}
+		*v = int32(n)
+		return nil
+	case *int64:
+		n, err := util.ParseInt(b, 10, 64)
+		if err != nil {
+			return err
+		}
+		*v = n
+		return nil
+	case *uint:
+		n, err := util.ParseUint(b, 10, 64)
+		if err != nil {
+			return err
+		}
+		*v = uint(n)
+		return nil
+	case *uint8:
+		n, err := util.ParseUint(b, 10, 8)
+		if err != nil {
+			return err
+		}
+		*v = uint8(n)
+		return nil
+	case *uint16:
+		n, err := util.ParseUint(b, 10, 16)
+		if err != nil {
+			return err
+		}
+		*v = uint16(n)
+		return nil
+	case *uint32:
+		n, err := util.ParseUint(b, 10, 32)
+		if err != nil {
+			return err
+		}
+		*v = uint32(n)
+		return nil
+	case *uint64:
+		n, err := util.ParseUint(b, 10, 64)
+		if err != nil {
+			return err
+		}
+		*v = n
+		return nil
+	case *float32:
+		n, err := util.ParseFloat(b, 32)
+		if err != nil {
+			return err
+		}
+		*v = float32(n)
+		return err
+	case *float64:
+		var err error
+		*v, err = util.ParseFloat(b, 64)
+		return err
+	case *bool:
+		*v = len(b) == 1 && b[0] == '1'
+		return nil
+	case encoding.BinaryUnmarshaler:
+		return v.UnmarshalBinary(b)
+	default:
+		return fmt.Errorf(
+			"redis: can't unmarshal %T (consider implementing BinaryUnmarshaler)", v)
+	}
+}
+
+func ScanSlice(data []string, slice interface{}) error {
+	v := reflect.ValueOf(slice)
+	if !v.IsValid() {
+		return fmt.Errorf("redis: ScanSlice(nil)")
+	}
+	if v.Kind() != reflect.Ptr {
+		return fmt.Errorf("redis: ScanSlice(non-pointer %T)", slice)
+	}
+	v = v.Elem()
+	if v.Kind() != reflect.Slice {
+		return fmt.Errorf("redis: ScanSlice(non-slice %T)", slice)
+	}
+
+	next := makeSliceNextElemFunc(v)
+	for i, s := range data {
+		elem := next()
+		if err := Scan([]byte(s), elem.Addr().Interface()); err != nil {
+			err = fmt.Errorf("redis: ScanSlice index=%d value=%q failed: %s", i, s, err)
+			return err
+		}
+	}
+
+	return nil
+}
+
+func makeSliceNextElemFunc(v reflect.Value) func() reflect.Value {
+	elemType := v.Type().Elem()
+
+	if elemType.Kind() == reflect.Ptr {
+		elemType = elemType.Elem()
+		return func() reflect.Value {
+			if v.Len() < v.Cap() {
+				v.Set(v.Slice(0, v.Len()+1))
+				elem := v.Index(v.Len() - 1)
+				if elem.IsNil() {
+					elem.Set(reflect.New(elemType))
+				}
+				return elem.Elem()
+			}
+
+			elem := reflect.New(elemType)
+			v.Set(reflect.Append(v, elem))
+			return elem.Elem()
+		}
+	}
+
+	zero := reflect.Zero(elemType)
+	return func() reflect.Value {
+		if v.Len() < v.Cap() {
+			v.Set(v.Slice(0, v.Len()+1))
+			return v.Index(v.Len() - 1)
+		}
+
+		v.Set(reflect.Append(v, zero))
+		return v.Index(v.Len() - 1)
+	}
+}

vendor/github.com/go-redis/redis/internal/proto/writer.go

@@ -0,0 +1,159 @@
+package proto
+
+import (
+	"bufio"
+	"encoding"
+	"fmt"
+	"io"
+	"strconv"
+
+	"github.com/go-redis/redis/internal/util"
+)
+
+type Writer struct {
+	wr *bufio.Writer
+
+	lenBuf []byte
+	numBuf []byte
+}
+
+func NewWriter(wr io.Writer) *Writer {
+	return &Writer{
+		wr: bufio.NewWriter(wr),
+
+		lenBuf: make([]byte, 64),
+		numBuf: make([]byte, 64),
+	}
+}
+
+func (w *Writer) WriteArgs(args []interface{}) error {
+	err := w.wr.WriteByte(ArrayReply)
+	if err != nil {
+		return err
+	}
+
+	err = w.writeLen(len(args))
+	if err != nil {
+		return err
+	}
+
+	for _, arg := range args {
+		err := w.writeArg(arg)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (w *Writer) writeLen(n int) error {
+	w.lenBuf = strconv.AppendUint(w.lenBuf[:0], uint64(n), 10)
+	w.lenBuf = append(w.lenBuf, '\r', '\n')
+	_, err := w.wr.Write(w.lenBuf)
+	return err
+}
+
+func (w *Writer) writeArg(v interface{}) error {
+	switch v := v.(type) {
+	case nil:
+		return w.string("")
+	case string:
+		return w.string(v)
+	case []byte:
+		return w.bytes(v)
+	case int:
+		return w.int(int64(v))
+	case int8:
+		return w.int(int64(v))
+	case int16:
+		return w.int(int64(v))
+	case int32:
+		return w.int(int64(v))
+	case int64:
+		return w.int(v)
+	case uint:
+		return w.uint(uint64(v))
+	case uint8:
+		return w.uint(uint64(v))
+	case uint16:
+		return w.uint(uint64(v))
+	case uint32:
+		return w.uint(uint64(v))
+	case uint64:
+		return w.uint(v)
+	case float32:
+		return w.float(float64(v))
+	case float64:
+		return w.float(v)
+	case bool:
+		if v {
+			return w.int(1)
+		} else {
+			return w.int(0)
+		}
+	case encoding.BinaryMarshaler:
+		b, err := v.MarshalBinary()
+		if err != nil {
+			return err
+		}
+		return w.bytes(b)
+	default:
+		return fmt.Errorf(
+			"redis: can't marshal %T (implement encoding.BinaryMarshaler)", v)
+	}
+}
+
+func (w *Writer) bytes(b []byte) error {
+	err := w.wr.WriteByte(StringReply)
+	if err != nil {
+		return err
+	}
+
+	err = w.writeLen(len(b))
+	if err != nil {
+		return err
+	}
+
+	_, err = w.wr.Write(b)
+	if err != nil {
+		return err
+	}
+
+	return w.crlf()
+}
+
+func (w *Writer) string(s string) error {
+	return w.bytes(util.StringToBytes(s))
+}
+
+func (w *Writer) uint(n uint64) error {
+	w.numBuf = strconv.AppendUint(w.numBuf[:0], n, 10)
+	return w.bytes(w.numBuf)
+}
+
+func (w *Writer) int(n int64) error {
+	w.numBuf = strconv.AppendInt(w.numBuf[:0], n, 10)
+	return w.bytes(w.numBuf)
+}
+
+func (w *Writer) float(f float64) error {
+	w.numBuf = strconv.AppendFloat(w.numBuf[:0], f, 'f', -1, 64)
+	return w.bytes(w.numBuf)
+}
+
+func (w *Writer) crlf() error {
+	err := w.wr.WriteByte('\r')
+	if err != nil {
+		return err
+	}
+	return w.wr.WriteByte('\n')
+}
+
+func (w *Writer) Reset(wr io.Writer) {
+	w.wr.Reset(wr)
+}
+
+func (w *Writer) Flush() error {
+	return w.wr.Flush()
+}

vendor/github.com/go-redis/redis/internal/util.go

@@ -0,0 +1,29 @@
+package internal
+
+import "github.com/go-redis/redis/internal/util"
+
+func ToLower(s string) string {
+	if isLower(s) {
+		return s
+	}
+
+	b := make([]byte, len(s))
+	for i := range b {
+		c := s[i]
+		if c >= 'A' && c <= 'Z' {
+			c += 'a' - 'A'
+		}
+		b[i] = c
+	}
+	return util.BytesToString(b)
+}
+
+func isLower(s string) bool {
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if c >= 'A' && c <= 'Z' {
+			return false
+		}
+	}
+	return true
+}

vendor/github.com/go-redis/redis/internal/util/safe.go

@@ -0,0 +1,11 @@
+// +build appengine
+
+package util
+
+func BytesToString(b []byte) string {
+	return string(b)
+}
+
+func StringToBytes(s string) []byte {
+	return []byte(s)
+}

vendor/github.com/go-redis/redis/internal/util/strconv.go

@@ -0,0 +1,19 @@
+package util
+
+import "strconv"
+
+func Atoi(b []byte) (int, error) {
+	return strconv.Atoi(BytesToString(b))
+}
+
+func ParseInt(b []byte, base int, bitSize int) (int64, error) {
+	return strconv.ParseInt(BytesToString(b), base, bitSize)
+}
+
+func ParseUint(b []byte, base int, bitSize int) (uint64, error) {
+	return strconv.ParseUint(BytesToString(b), base, bitSize)
+}
+
+func ParseFloat(b []byte, bitSize int) (float64, error) {
+	return strconv.ParseFloat(BytesToString(b), bitSize)
+}

vendor/github.com/go-redis/redis/internal/util/unsafe.go

@@ -0,0 +1,22 @@
+// +build !appengine
+
+package util
+
+import (
+	"unsafe"
+)
+
+// BytesToString converts byte slice to string.
+func BytesToString(b []byte) string {
+	return *(*string)(unsafe.Pointer(&b))
+}
+
+// StringToBytes converts string to byte slice.
+func StringToBytes(s string) []byte {
+	return *(*[]byte)(unsafe.Pointer(
+		&struct {
+			string
+			Cap int
+		}{s, len(s)},
+	))
+}

vendor/github.com/go-redis/redis/iterator.go

@@ -0,0 +1,73 @@
+package redis
+
+import "sync"
+
+// ScanIterator is used to incrementally iterate over a collection of elements.
+// It's safe for concurrent use by multiple goroutines.
+type ScanIterator struct {
+	mu  sync.Mutex // protects Scanner and pos
+	cmd *ScanCmd
+	pos int
+}
+
+// Err returns the last iterator error, if any.
+func (it *ScanIterator) Err() error {
+	it.mu.Lock()
+	err := it.cmd.Err()
+	it.mu.Unlock()
+	return err
+}
+
+// Next advances the cursor and returns true if more values can be read.
+func (it *ScanIterator) Next() bool {
+	it.mu.Lock()
+	defer it.mu.Unlock()
+
+	// Instantly return on errors.
+	if it.cmd.Err() != nil {
+		return false
+	}
+
+	// Advance cursor, check if we are still within range.
+	if it.pos < len(it.cmd.page) {
+		it.pos++
+		return true
+	}
+
+	for {
+		// Return if there is no more data to fetch.
+		if it.cmd.cursor == 0 {
+			return false
+		}
+
+		// Fetch next page.
+		if it.cmd._args[0] == "scan" {
+			it.cmd._args[1] = it.cmd.cursor
+		} else {
+			it.cmd._args[2] = it.cmd.cursor
+		}
+
+		err := it.cmd.process(it.cmd)
+		if err != nil {
+			return false
+		}
+
+		it.pos = 1
+
+		// Redis can occasionally return empty page.
+		if len(it.cmd.page) > 0 {
+			return true
+		}
+	}
+}
+
+// Val returns the key/field at the current cursor position.
+func (it *ScanIterator) Val() string {
+	var v string
+	it.mu.Lock()
+	if it.cmd.Err() == nil && it.pos > 0 && it.pos <= len(it.cmd.page) {
+		v = it.cmd.page[it.pos-1]
+	}
+	it.mu.Unlock()
+	return v
+}

vendor/github.com/go-redis/redis/options.go

@@ -0,0 +1,226 @@
+package redis
+
+import (
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net"
+	"net/url"
+	"runtime"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/go-redis/redis/internal/pool"
+)
+
+// Limiter is the interface of a rate limiter or a circuit breaker.
+type Limiter interface {
+	// Allow returns a nil if operation is allowed or an error otherwise.
+	// If operation is allowed client must report the result of operation
+	// whether is a success or a failure.
+	Allow() error
+	// ReportResult reports the result of previously allowed operation.
+	// nil indicates a success, non-nil error indicates a failure.
+	ReportResult(result error)
+}
+
+type Options struct {
+	// The network type, either tcp or unix.
+	// Default is tcp.
+	Network string
+	// host:port address.
+	Addr string
+
+	// Dialer creates new network connection and has priority over
+	// Network and Addr options.
+	Dialer func() (net.Conn, error)
+
+	// Hook that is called when new connection is established.
+	OnConnect func(*Conn) error
+
+	// Optional password. Must match the password specified in the
+	// requirepass server configuration option.
+	Password string
+	// Database to be selected after connecting to the server.
+	DB int
+
+	// Maximum number of retries before giving up.
+	// Default is to not retry failed commands.
+	MaxRetries int
+	// Minimum backoff between each retry.
+	// Default is 8 milliseconds; -1 disables backoff.
+	MinRetryBackoff time.Duration
+	// Maximum backoff between each retry.
+	// Default is 512 milliseconds; -1 disables backoff.
+	MaxRetryBackoff time.Duration
+
+	// Dial timeout for establishing new connections.
+	// Default is 5 seconds.
+	DialTimeout time.Duration
+	// Timeout for socket reads. If reached, commands will fail
+	// with a timeout instead of blocking. Use value -1 for no timeout and 0 for default.
+	// Default is 3 seconds.
+	ReadTimeout time.Duration
+	// Timeout for socket writes. If reached, commands will fail
+	// with a timeout instead of blocking.
+	// Default is ReadTimeout.
+	WriteTimeout time.Duration
+
+	// Maximum number of socket connections.
+	// Default is 10 connections per every CPU as reported by runtime.NumCPU.
+	PoolSize int
+	// Minimum number of idle connections which is useful when establishing
+	// new connection is slow.
+	MinIdleConns int
+	// Connection age at which client retires (closes) the connection.
+	// Default is to not close aged connections.
+	MaxConnAge time.Duration
+	// Amount of time client waits for connection if all connections
+	// are busy before returning an error.
+	// Default is ReadTimeout + 1 second.
+	PoolTimeout time.Duration
+	// Amount of time after which client closes idle connections.
+	// Should be less than server's timeout.
+	// Default is 5 minutes. -1 disables idle timeout check.
+	IdleTimeout time.Duration
+	// Frequency of idle checks made by idle connections reaper.
+	// Default is 1 minute. -1 disables idle connections reaper,
+	// but idle connections are still discarded by the client
+	// if IdleTimeout is set.
+	IdleCheckFrequency time.Duration
+
+	// Enables read only queries on slave nodes.
+	readOnly bool
+
+	// TLS Config to use. When set TLS will be negotiated.
+	TLSConfig *tls.Config
+}
+
+func (opt *Options) init() {
+	if opt.Network == "" {
+		opt.Network = "tcp"
+	}
+	if opt.Addr == "" {
+		opt.Addr = "localhost:6379"
+	}
+	if opt.Dialer == nil {
+		opt.Dialer = func() (net.Conn, error) {
+			netDialer := &net.Dialer{
+				Timeout:   opt.DialTimeout,
+				KeepAlive: 5 * time.Minute,
+			}
+			if opt.TLSConfig == nil {
+				return netDialer.Dial(opt.Network, opt.Addr)
+			} else {
+				return tls.DialWithDialer(netDialer, opt.Network, opt.Addr, opt.TLSConfig)
+			}
+		}
+	}
+	if opt.PoolSize == 0 {
+		opt.PoolSize = 10 * runtime.NumCPU()
+	}
+	if opt.DialTimeout == 0 {
+		opt.DialTimeout = 5 * time.Second
+	}
+	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
+	}
+	if opt.PoolTimeout == 0 {
+		opt.PoolTimeout = opt.ReadTimeout + time.Second
+	}
+	if opt.IdleTimeout == 0 {
+		opt.IdleTimeout = 5 * time.Minute
+	}
+	if opt.IdleCheckFrequency == 0 {
+		opt.IdleCheckFrequency = time.Minute
+	}
+
+	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
+	}
+}
+
+// ParseURL parses an URL into Options that can be used to connect to Redis.
+func ParseURL(redisURL string) (*Options, error) {
+	o := &Options{Network: "tcp"}
+	u, err := url.Parse(redisURL)
+	if err != nil {
+		return nil, err
+	}
+
+	if u.Scheme != "redis" && u.Scheme != "rediss" {
+		return nil, errors.New("invalid redis URL scheme: " + u.Scheme)
+	}
+
+	if u.User != nil {
+		if p, ok := u.User.Password(); ok {
+			o.Password = p
+		}
+	}
+
+	if len(u.Query()) > 0 {
+		return nil, errors.New("no options supported")
+	}
+
+	h, p, err := net.SplitHostPort(u.Host)
+	if err != nil {
+		h = u.Host
+	}
+	if h == "" {
+		h = "localhost"
+	}
+	if p == "" {
+		p = "6379"
+	}
+	o.Addr = net.JoinHostPort(h, p)
+
+	f := strings.FieldsFunc(u.Path, func(r rune) bool {
+		return r == '/'
+	})
+	switch len(f) {
+	case 0:
+		o.DB = 0
+	case 1:
+		if o.DB, err = strconv.Atoi(f[0]); err != nil {
+			return nil, fmt.Errorf("invalid redis database number: %q", f[0])
+		}
+	default:
+		return nil, errors.New("invalid redis URL path: " + u.Path)
+	}
+
+	if u.Scheme == "rediss" {
+		o.TLSConfig = &tls.Config{ServerName: h}
+	}
+	return o, nil
+}
+
+func newConnPool(opt *Options) *pool.ConnPool {
+	return pool.NewConnPool(&pool.Options{
+		Dialer:             opt.Dialer,
+		PoolSize:           opt.PoolSize,
+		MinIdleConns:       opt.MinIdleConns,
+		MaxConnAge:         opt.MaxConnAge,
+		PoolTimeout:        opt.PoolTimeout,
+		IdleTimeout:        opt.IdleTimeout,
+		IdleCheckFrequency: opt.IdleCheckFrequency,
+	})
+}

vendor/github.com/go-redis/redis/pipeline.go

@@ -0,0 +1,120 @@
+package redis
+
+import (
+	"sync"
+
+	"github.com/go-redis/redis/internal/pool"
+)
+
+type pipelineExecer func([]Cmder) error
+
+type Pipeliner interface {
+	StatefulCmdable
+	Do(args ...interface{}) *Cmd
+	Process(cmd Cmder) error
+	Close() error
+	Discard() error
+	Exec() ([]Cmder, error)
+}
+
+var _ Pipeliner = (*Pipeline)(nil)
+
+// Pipeline implements pipelining as described in
+// http://redis.io/topics/pipelining. It's safe for concurrent use
+// by multiple goroutines.
+type Pipeline struct {
+	statefulCmdable
+
+	exec pipelineExecer
+
+	mu     sync.Mutex
+	cmds   []Cmder
+	closed bool
+}
+
+func (c *Pipeline) Do(args ...interface{}) *Cmd {
+	cmd := NewCmd(args...)
+	_ = c.Process(cmd)
+	return cmd
+}
+
+// Process queues the cmd for later execution.
+func (c *Pipeline) Process(cmd Cmder) error {
+	c.mu.Lock()
+	c.cmds = append(c.cmds, cmd)
+	c.mu.Unlock()
+	return nil
+}
+
+// Close closes the pipeline, releasing any open resources.
+func (c *Pipeline) Close() error {
+	c.mu.Lock()
+	c.discard()
+	c.closed = true
+	c.mu.Unlock()
+	return nil
+}
+
+// Discard resets the pipeline and discards queued commands.
+func (c *Pipeline) Discard() error {
+	c.mu.Lock()
+	err := c.discard()
+	c.mu.Unlock()
+	return err
+}
+
+func (c *Pipeline) discard() error {
+	if c.closed {
+		return pool.ErrClosed
+	}
+	c.cmds = c.cmds[:0]
+	return nil
+}
+
+// Exec executes all previously queued commands using one
+// client-server roundtrip.
+//
+// Exec always returns list of commands and error of the first failed
+// command if any.
+func (c *Pipeline) Exec() ([]Cmder, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	if c.closed {
+		return nil, pool.ErrClosed
+	}
+
+	if len(c.cmds) == 0 {
+		return nil, nil
+	}
+
+	cmds := c.cmds
+	c.cmds = nil
+
+	return cmds, c.exec(cmds)
+}
+
+func (c *Pipeline) pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	if err := fn(c); err != nil {
+		return nil, err
+	}
+	cmds, err := c.Exec()
+	_ = c.Close()
+	return cmds, err
+}
+
+func (c *Pipeline) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.pipelined(fn)
+}
+
+func (c *Pipeline) Pipeline() Pipeliner {
+	return c
+}
+
+func (c *Pipeline) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.pipelined(fn)
+}
+
+func (c *Pipeline) TxPipeline() Pipeliner {
+	return c
+}

vendor/github.com/go-redis/redis/pubsub.go

@@ -0,0 +1,473 @@
+package redis
+
+import (
+	"errors"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/go-redis/redis/internal"
+	"github.com/go-redis/redis/internal/pool"
+	"github.com/go-redis/redis/internal/proto"
+)
+
+var errPingTimeout = errors.New("redis: ping timeout")
+
+// PubSub implements Pub/Sub commands bas described in
+// http://redis.io/topics/pubsub. Message receiving is NOT safe
+// for concurrent use by multiple goroutines.
+//
+// PubSub automatically reconnects to Redis Server and resubscribes
+// to the channels in case of network errors.
+type PubSub struct {
+	opt *Options
+
+	newConn   func([]string) (*pool.Conn, error)
+	closeConn func(*pool.Conn) error
+
+	mu       sync.Mutex
+	cn       *pool.Conn
+	channels map[string]struct{}
+	patterns map[string]struct{}
+	closed   bool
+	exit     chan struct{}
+
+	cmd *Cmd
+
+	chOnce sync.Once
+	ch     chan *Message
+	ping   chan struct{}
+}
+
+func (c *PubSub) init() {
+	c.exit = make(chan struct{})
+}
+
+func (c *PubSub) conn() (*pool.Conn, error) {
+	c.mu.Lock()
+	cn, err := c._conn(nil)
+	c.mu.Unlock()
+	return cn, err
+}
+
+func (c *PubSub) _conn(newChannels []string) (*pool.Conn, error) {
+	if c.closed {
+		return nil, pool.ErrClosed
+	}
+	if c.cn != nil {
+		return c.cn, nil
+	}
+
+	channels := mapKeys(c.channels)
+	channels = append(channels, newChannels...)
+
+	cn, err := c.newConn(channels)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := c.resubscribe(cn); err != nil {
+		_ = c.closeConn(cn)
+		return nil, err
+	}
+
+	c.cn = cn
+	return cn, nil
+}
+
+func (c *PubSub) writeCmd(cn *pool.Conn, cmd Cmder) error {
+	return cn.WithWriter(c.opt.WriteTimeout, func(wr *proto.Writer) error {
+		return writeCmd(wr, cmd)
+	})
+}
+
+func (c *PubSub) resubscribe(cn *pool.Conn) error {
+	var firstErr error
+
+	if len(c.channels) > 0 {
+		err := c._subscribe(cn, "subscribe", mapKeys(c.channels))
+		if err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+
+	if len(c.patterns) > 0 {
+		err := c._subscribe(cn, "psubscribe", mapKeys(c.patterns))
+		if err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+
+	return firstErr
+}
+
+func mapKeys(m map[string]struct{}) []string {
+	s := make([]string, len(m))
+	i := 0
+	for k := range m {
+		s[i] = k
+		i++
+	}
+	return s
+}
+
+func (c *PubSub) _subscribe(
+	cn *pool.Conn, redisCmd string, channels []string,
+) error {
+	args := make([]interface{}, 0, 1+len(channels))
+	args = append(args, redisCmd)
+	for _, channel := range channels {
+		args = append(args, channel)
+	}
+	cmd := NewSliceCmd(args...)
+	return c.writeCmd(cn, cmd)
+}
+
+func (c *PubSub) releaseConn(cn *pool.Conn, err error, allowTimeout bool) {
+	c.mu.Lock()
+	c._releaseConn(cn, err, allowTimeout)
+	c.mu.Unlock()
+}
+
+func (c *PubSub) _releaseConn(cn *pool.Conn, err error, allowTimeout bool) {
+	if c.cn != cn {
+		return
+	}
+	if internal.IsBadConn(err, allowTimeout) {
+		c._reconnect(err)
+	}
+}
+
+func (c *PubSub) _reconnect(reason error) {
+	_ = c._closeTheCn(reason)
+	_, _ = c._conn(nil)
+}
+
+func (c *PubSub) _closeTheCn(reason error) error {
+	if c.cn == nil {
+		return nil
+	}
+	if !c.closed {
+		internal.Logf("redis: discarding bad PubSub connection: %s", reason)
+	}
+	err := c.closeConn(c.cn)
+	c.cn = nil
+	return err
+}
+
+func (c *PubSub) Close() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	if c.closed {
+		return pool.ErrClosed
+	}
+	c.closed = true
+	close(c.exit)
+
+	err := c._closeTheCn(pool.ErrClosed)
+	return err
+}
+
+// Subscribe the client to the specified channels. It returns
+// empty subscription if there are no channels.
+func (c *PubSub) Subscribe(channels ...string) error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	err := c.subscribe("subscribe", channels...)
+	if c.channels == nil {
+		c.channels = make(map[string]struct{})
+	}
+	for _, s := range channels {
+		c.channels[s] = struct{}{}
+	}
+	return err
+}
+
+// PSubscribe the client to the given patterns. It returns
+// empty subscription if there are no patterns.
+func (c *PubSub) PSubscribe(patterns ...string) error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	err := c.subscribe("psubscribe", patterns...)
+	if c.patterns == nil {
+		c.patterns = make(map[string]struct{})
+	}
+	for _, s := range patterns {
+		c.patterns[s] = struct{}{}
+	}
+	return err
+}
+
+// Unsubscribe the client from the given channels, or from all of
+// them if none is given.
+func (c *PubSub) Unsubscribe(channels ...string) error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	for _, channel := range channels {
+		delete(c.channels, channel)
+	}
+	err := c.subscribe("unsubscribe", channels...)
+	return err
+}
+
+// PUnsubscribe the client from the given patterns, or from all of
+// them if none is given.
+func (c *PubSub) PUnsubscribe(patterns ...string) error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	for _, pattern := range patterns {
+		delete(c.patterns, pattern)
+	}
+	err := c.subscribe("punsubscribe", patterns...)
+	return err
+}
+
+func (c *PubSub) subscribe(redisCmd string, channels ...string) error {
+	cn, err := c._conn(channels)
+	if err != nil {
+		return err
+	}
+
+	err = c._subscribe(cn, redisCmd, channels)
+	c._releaseConn(cn, err, false)
+	return err
+}
+
+func (c *PubSub) Ping(payload ...string) error {
+	args := []interface{}{"ping"}
+	if len(payload) == 1 {
+		args = append(args, payload[0])
+	}
+	cmd := NewCmd(args...)
+
+	cn, err := c.conn()
+	if err != nil {
+		return err
+	}
+
+	err = c.writeCmd(cn, cmd)
+	c.releaseConn(cn, err, false)
+	return err
+}
+
+// Subscription received after a successful subscription to channel.
+type Subscription struct {
+	// Can be "subscribe", "unsubscribe", "psubscribe" or "punsubscribe".
+	Kind string
+	// Channel name we have subscribed to.
+	Channel string
+	// Number of channels we are currently subscribed to.
+	Count int
+}
+
+func (m *Subscription) String() string {
+	return fmt.Sprintf("%s: %s", m.Kind, m.Channel)
+}
+
+// Message received as result of a PUBLISH command issued by another client.
+type Message struct {
+	Channel string
+	Pattern string
+	Payload string
+}
+
+func (m *Message) String() string {
+	return fmt.Sprintf("Message<%s: %s>", m.Channel, m.Payload)
+}
+
+// Pong received as result of a PING command issued by another client.
+type Pong struct {
+	Payload string
+}
+
+func (p *Pong) String() string {
+	if p.Payload != "" {
+		return fmt.Sprintf("Pong<%s>", p.Payload)
+	}
+	return "Pong"
+}
+
+func (c *PubSub) newMessage(reply interface{}) (interface{}, error) {
+	switch reply := reply.(type) {
+	case string:
+		return &Pong{
+			Payload: reply,
+		}, nil
+	case []interface{}:
+		switch kind := reply[0].(string); kind {
+		case "subscribe", "unsubscribe", "psubscribe", "punsubscribe":
+			return &Subscription{
+				Kind:    kind,
+				Channel: reply[1].(string),
+				Count:   int(reply[2].(int64)),
+			}, nil
+		case "message":
+			return &Message{
+				Channel: reply[1].(string),
+				Payload: reply[2].(string),
+			}, nil
+		case "pmessage":
+			return &Message{
+				Pattern: reply[1].(string),
+				Channel: reply[2].(string),
+				Payload: reply[3].(string),
+			}, nil
+		case "pong":
+			return &Pong{
+				Payload: reply[1].(string),
+			}, nil
+		default:
+			return nil, fmt.Errorf("redis: unsupported pubsub message: %q", kind)
+		}
+	default:
+		return nil, fmt.Errorf("redis: unsupported pubsub message: %#v", reply)
+	}
+}
+
+// ReceiveTimeout acts like Receive but returns an error if message
+// is not received in time. This is low-level API and in most cases
+// Channel should be used instead.
+func (c *PubSub) ReceiveTimeout(timeout time.Duration) (interface{}, error) {
+	if c.cmd == nil {
+		c.cmd = NewCmd()
+	}
+
+	cn, err := c.conn()
+	if err != nil {
+		return nil, err
+	}
+
+	err = cn.WithReader(timeout, func(rd *proto.Reader) error {
+		return c.cmd.readReply(rd)
+	})
+
+	c.releaseConn(cn, err, timeout > 0)
+	if err != nil {
+		return nil, err
+	}
+
+	return c.newMessage(c.cmd.Val())
+}
+
+// Receive returns a message as a Subscription, Message, Pong or error.
+// See PubSub example for details. This is low-level API and in most cases
+// Channel should be used instead.
+func (c *PubSub) Receive() (interface{}, error) {
+	return c.ReceiveTimeout(0)
+}
+
+// ReceiveMessage returns a Message or error ignoring Subscription and Pong
+// messages. This is low-level API and in most cases Channel should be used
+// instead.
+func (c *PubSub) ReceiveMessage() (*Message, error) {
+	for {
+		msg, err := c.Receive()
+		if err != nil {
+			return nil, err
+		}
+
+		switch msg := msg.(type) {
+		case *Subscription:
+			// Ignore.
+		case *Pong:
+			// Ignore.
+		case *Message:
+			return msg, nil
+		default:
+			err := fmt.Errorf("redis: unknown message: %T", msg)
+			return nil, err
+		}
+	}
+}
+
+// Channel returns a Go channel for concurrently receiving messages.
+// It periodically sends Ping messages to test connection health.
+// The channel is closed with PubSub. Receive* APIs can not be used
+// after channel is created.
+func (c *PubSub) Channel() <-chan *Message {
+	c.chOnce.Do(c.initChannel)
+	return c.ch
+}
+
+func (c *PubSub) initChannel() {
+	c.ch = make(chan *Message, 100)
+	c.ping = make(chan struct{}, 10)
+
+	go func() {
+		var errCount int
+		for {
+			msg, err := c.Receive()
+			if err != nil {
+				if err == pool.ErrClosed {
+					close(c.ch)
+					return
+				}
+				if errCount > 0 {
+					time.Sleep(c.retryBackoff(errCount))
+				}
+				errCount++
+				continue
+			}
+			errCount = 0
+
+			// Any message is as good as a ping.
+			select {
+			case c.ping <- struct{}{}:
+			default:
+			}
+
+			switch msg := msg.(type) {
+			case *Subscription:
+				// Ignore.
+			case *Pong:
+				// Ignore.
+			case *Message:
+				c.ch <- msg
+			default:
+				internal.Logf("redis: unknown message: %T", msg)
+			}
+		}
+	}()
+
+	go func() {
+		const timeout = 5 * time.Second
+
+		timer := time.NewTimer(timeout)
+		timer.Stop()
+
+		healthy := true
+		for {
+			timer.Reset(timeout)
+			select {
+			case <-c.ping:
+				healthy = true
+				if !timer.Stop() {
+					<-timer.C
+				}
+			case <-timer.C:
+				pingErr := c.Ping()
+				if healthy {
+					healthy = false
+				} else {
+					if pingErr == nil {
+						pingErr = errPingTimeout
+					}
+					c.mu.Lock()
+					c._reconnect(pingErr)
+					c.mu.Unlock()
+				}
+			case <-c.exit:
+				return
+			}
+		}
+	}()
+}
+
+func (c *PubSub) retryBackoff(attempt int) time.Duration {
+	return internal.RetryBackoff(attempt, c.opt.MinRetryBackoff, c.opt.MaxRetryBackoff)
+}

vendor/github.com/go-redis/redis/redis.go

@@ -0,0 +1,580 @@
+package redis
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"os"
+	"time"
+
+	"github.com/go-redis/redis/internal"
+	"github.com/go-redis/redis/internal/pool"
+	"github.com/go-redis/redis/internal/proto"
+)
+
+// Nil reply Redis returns when key does not exist.
+const Nil = proto.Nil
+
+func init() {
+	SetLogger(log.New(os.Stderr, "redis: ", log.LstdFlags|log.Lshortfile))
+}
+
+func SetLogger(logger *log.Logger) {
+	internal.Logger = logger
+}
+
+type baseClient struct {
+	opt      *Options
+	connPool pool.Pooler
+	limiter  Limiter
+
+	process           func(Cmder) error
+	processPipeline   func([]Cmder) error
+	processTxPipeline func([]Cmder) error
+
+	onClose func() error // hook called when client is closed
+}
+
+func (c *baseClient) init() {
+	c.process = c.defaultProcess
+	c.processPipeline = c.defaultProcessPipeline
+	c.processTxPipeline = c.defaultProcessTxPipeline
+}
+
+func (c *baseClient) String() string {
+	return fmt.Sprintf("Redis<%s db:%d>", c.getAddr(), c.opt.DB)
+}
+
+func (c *baseClient) newConn() (*pool.Conn, error) {
+	cn, err := c.connPool.NewConn()
+	if err != nil {
+		return nil, err
+	}
+
+	if cn.InitedAt.IsZero() {
+		if err := c.initConn(cn); err != nil {
+			_ = c.connPool.CloseConn(cn)
+			return nil, err
+		}
+	}
+
+	return cn, nil
+}
+
+func (c *baseClient) getConn() (*pool.Conn, error) {
+	if c.limiter != nil {
+		err := c.limiter.Allow()
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	cn, err := c._getConn()
+	if err != nil {
+		if c.limiter != nil {
+			c.limiter.ReportResult(err)
+		}
+		return nil, err
+	}
+	return cn, nil
+}
+
+func (c *baseClient) _getConn() (*pool.Conn, error) {
+	cn, err := c.connPool.Get()
+	if err != nil {
+		return nil, err
+	}
+
+	if cn.InitedAt.IsZero() {
+		err := c.initConn(cn)
+		if err != nil {
+			c.connPool.Remove(cn)
+			return nil, err
+		}
+	}
+
+	return cn, nil
+}
+
+func (c *baseClient) releaseConn(cn *pool.Conn, err error) {
+	if c.limiter != nil {
+		c.limiter.ReportResult(err)
+	}
+
+	if internal.IsBadConn(err, false) {
+		c.connPool.Remove(cn)
+	} else {
+		c.connPool.Put(cn)
+	}
+}
+
+func (c *baseClient) releaseConnStrict(cn *pool.Conn, err error) {
+	if c.limiter != nil {
+		c.limiter.ReportResult(err)
+	}
+
+	if err == nil || internal.IsRedisError(err) {
+		c.connPool.Put(cn)
+	} else {
+		c.connPool.Remove(cn)
+	}
+}
+
+func (c *baseClient) initConn(cn *pool.Conn) error {
+	cn.InitedAt = time.Now()
+
+	if c.opt.Password == "" &&
+		c.opt.DB == 0 &&
+		!c.opt.readOnly &&
+		c.opt.OnConnect == nil {
+		return nil
+	}
+
+	conn := newConn(c.opt, cn)
+	_, err := conn.Pipelined(func(pipe Pipeliner) error {
+		if c.opt.Password != "" {
+			pipe.Auth(c.opt.Password)
+		}
+
+		if c.opt.DB > 0 {
+			pipe.Select(c.opt.DB)
+		}
+
+		if c.opt.readOnly {
+			pipe.ReadOnly()
+		}
+
+		return nil
+	})
+	if err != nil {
+		return err
+	}
+
+	if c.opt.OnConnect != nil {
+		return c.opt.OnConnect(conn)
+	}
+	return nil
+}
+
+// Do creates a Cmd from the args and processes the cmd.
+func (c *baseClient) Do(args ...interface{}) *Cmd {
+	cmd := NewCmd(args...)
+	_ = c.Process(cmd)
+	return cmd
+}
+
+// WrapProcess wraps function that processes Redis commands.
+func (c *baseClient) WrapProcess(
+	fn func(oldProcess func(cmd Cmder) error) func(cmd Cmder) error,
+) {
+	c.process = fn(c.process)
+}
+
+func (c *baseClient) Process(cmd Cmder) error {
+	return c.process(cmd)
+}
+
+func (c *baseClient) defaultProcess(cmd Cmder) error {
+	for attempt := 0; attempt <= c.opt.MaxRetries; attempt++ {
+		if attempt > 0 {
+			time.Sleep(c.retryBackoff(attempt))
+		}
+
+		cn, err := c.getConn()
+		if err != nil {
+			cmd.setErr(err)
+			if internal.IsRetryableError(err, true) {
+				continue
+			}
+			return err
+		}
+
+		err = cn.WithWriter(c.opt.WriteTimeout, func(wr *proto.Writer) error {
+			return writeCmd(wr, cmd)
+		})
+		if err != nil {
+			c.releaseConn(cn, err)
+			cmd.setErr(err)
+			if internal.IsRetryableError(err, true) {
+				continue
+			}
+			return err
+		}
+
+		err = cn.WithReader(c.cmdTimeout(cmd), func(rd *proto.Reader) error {
+			return cmd.readReply(rd)
+		})
+		c.releaseConn(cn, err)
+		if err != nil && internal.IsRetryableError(err, cmd.readTimeout() == nil) {
+			continue
+		}
+
+		return err
+	}
+
+	return cmd.Err()
+}
+
+func (c *baseClient) retryBackoff(attempt int) time.Duration {
+	return internal.RetryBackoff(attempt, c.opt.MinRetryBackoff, c.opt.MaxRetryBackoff)
+}
+
+func (c *baseClient) cmdTimeout(cmd Cmder) time.Duration {
+	if timeout := cmd.readTimeout(); timeout != nil {
+		t := *timeout
+		if t == 0 {
+			return 0
+		}
+		return t + 10*time.Second
+	}
+	return c.opt.ReadTimeout
+}
+
+// Close closes the client, releasing any open resources.
+//
+// It is rare to Close a Client, as the Client is meant to be
+// long-lived and shared between many goroutines.
+func (c *baseClient) Close() error {
+	var firstErr error
+	if c.onClose != nil {
+		if err := c.onClose(); err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+	if err := c.connPool.Close(); err != nil && firstErr == nil {
+		firstErr = err
+	}
+	return firstErr
+}
+
+func (c *baseClient) getAddr() string {
+	return c.opt.Addr
+}
+
+func (c *baseClient) WrapProcessPipeline(
+	fn func(oldProcess func([]Cmder) error) func([]Cmder) error,
+) {
+	c.processPipeline = fn(c.processPipeline)
+	c.processTxPipeline = fn(c.processTxPipeline)
+}
+
+func (c *baseClient) defaultProcessPipeline(cmds []Cmder) error {
+	return c.generalProcessPipeline(cmds, c.pipelineProcessCmds)
+}
+
+func (c *baseClient) defaultProcessTxPipeline(cmds []Cmder) error {
+	return c.generalProcessPipeline(cmds, c.txPipelineProcessCmds)
+}
+
+type pipelineProcessor func(*pool.Conn, []Cmder) (bool, error)
+
+func (c *baseClient) generalProcessPipeline(cmds []Cmder, p pipelineProcessor) error {
+	for attempt := 0; attempt <= c.opt.MaxRetries; attempt++ {
+		if attempt > 0 {
+			time.Sleep(c.retryBackoff(attempt))
+		}
+
+		cn, err := c.getConn()
+		if err != nil {
+			setCmdsErr(cmds, err)
+			return err
+		}
+
+		canRetry, err := p(cn, cmds)
+		c.releaseConnStrict(cn, err)
+
+		if !canRetry || !internal.IsRetryableError(err, true) {
+			break
+		}
+	}
+	return cmdsFirstErr(cmds)
+}
+
+func (c *baseClient) pipelineProcessCmds(cn *pool.Conn, cmds []Cmder) (bool, error) {
+	err := cn.WithWriter(c.opt.WriteTimeout, func(wr *proto.Writer) error {
+		return writeCmd(wr, cmds...)
+	})
+	if err != nil {
+		setCmdsErr(cmds, err)
+		return true, err
+	}
+
+	err = cn.WithReader(c.opt.ReadTimeout, func(rd *proto.Reader) error {
+		return pipelineReadCmds(rd, cmds)
+	})
+	return true, err
+}
+
+func pipelineReadCmds(rd *proto.Reader, cmds []Cmder) error {
+	for _, cmd := range cmds {
+		err := cmd.readReply(rd)
+		if err != nil && !internal.IsRedisError(err) {
+			return err
+		}
+	}
+	return nil
+}
+
+func (c *baseClient) txPipelineProcessCmds(cn *pool.Conn, cmds []Cmder) (bool, error) {
+	err := cn.WithWriter(c.opt.WriteTimeout, func(wr *proto.Writer) error {
+		return txPipelineWriteMulti(wr, cmds)
+	})
+	if err != nil {
+		setCmdsErr(cmds, err)
+		return true, err
+	}
+
+	err = cn.WithReader(c.opt.ReadTimeout, func(rd *proto.Reader) error {
+		err := txPipelineReadQueued(rd, cmds)
+		if err != nil {
+			setCmdsErr(cmds, err)
+			return err
+		}
+		return pipelineReadCmds(rd, cmds)
+	})
+	return false, err
+}
+
+func txPipelineWriteMulti(wr *proto.Writer, cmds []Cmder) error {
+	multiExec := make([]Cmder, 0, len(cmds)+2)
+	multiExec = append(multiExec, NewStatusCmd("MULTI"))
+	multiExec = append(multiExec, cmds...)
+	multiExec = append(multiExec, NewSliceCmd("EXEC"))
+	return writeCmd(wr, multiExec...)
+}
+
+func txPipelineReadQueued(rd *proto.Reader, cmds []Cmder) error {
+	// Parse queued replies.
+	var statusCmd StatusCmd
+	err := statusCmd.readReply(rd)
+	if err != nil {
+		return err
+	}
+
+	for range cmds {
+		err = statusCmd.readReply(rd)
+		if err != nil && !internal.IsRedisError(err) {
+			return err
+		}
+	}
+
+	// Parse number of replies.
+	line, err := rd.ReadLine()
+	if err != nil {
+		if err == Nil {
+			err = TxFailedErr
+		}
+		return err
+	}
+
+	switch line[0] {
+	case proto.ErrorReply:
+		return proto.ParseErrorReply(line)
+	case proto.ArrayReply:
+		// ok
+	default:
+		err := fmt.Errorf("redis: expected '*', but got line %q", line)
+		return err
+	}
+
+	return nil
+}
+
+//------------------------------------------------------------------------------
+
+// Client is a Redis client representing a pool of zero or more
+// underlying connections. It's safe for concurrent use by multiple
+// goroutines.
+type Client struct {
+	baseClient
+	cmdable
+
+	ctx context.Context
+}
+
+// NewClient returns a client to the Redis Server specified by Options.
+func NewClient(opt *Options) *Client {
+	opt.init()
+
+	c := Client{
+		baseClient: baseClient{
+			opt:      opt,
+			connPool: newConnPool(opt),
+		},
+	}
+	c.baseClient.init()
+	c.init()
+
+	return &c
+}
+
+func (c *Client) init() {
+	c.cmdable.setProcessor(c.Process)
+}
+
+func (c *Client) Context() context.Context {
+	if c.ctx != nil {
+		return c.ctx
+	}
+	return context.Background()
+}
+
+func (c *Client) WithContext(ctx context.Context) *Client {
+	if ctx == nil {
+		panic("nil context")
+	}
+	c2 := c.clone()
+	c2.ctx = ctx
+	return c2
+}
+
+func (c *Client) clone() *Client {
+	cp := *c
+	cp.init()
+	return &cp
+}
+
+// Options returns read-only Options that were used to create the client.
+func (c *Client) Options() *Options {
+	return c.opt
+}
+
+func (c *Client) SetLimiter(l Limiter) *Client {
+	c.limiter = l
+	return c
+}
+
+type PoolStats pool.Stats
+
+// PoolStats returns connection pool stats.
+func (c *Client) PoolStats() *PoolStats {
+	stats := c.connPool.Stats()
+	return (*PoolStats)(stats)
+}
+
+func (c *Client) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.Pipeline().Pipelined(fn)
+}
+
+func (c *Client) Pipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processPipeline,
+	}
+	pipe.statefulCmdable.setProcessor(pipe.Process)
+	return &pipe
+}
+
+func (c *Client) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.TxPipeline().Pipelined(fn)
+}
+
+// TxPipeline acts like Pipeline, but wraps queued commands with MULTI/EXEC.
+func (c *Client) TxPipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processTxPipeline,
+	}
+	pipe.statefulCmdable.setProcessor(pipe.Process)
+	return &pipe
+}
+
+func (c *Client) pubSub() *PubSub {
+	pubsub := &PubSub{
+		opt: c.opt,
+
+		newConn: func(channels []string) (*pool.Conn, error) {
+			return c.newConn()
+		},
+		closeConn: c.connPool.CloseConn,
+	}
+	pubsub.init()
+	return pubsub
+}
+
+// Subscribe subscribes the client to the specified channels.
+// Channels can be omitted to create empty subscription.
+// Note that this method does not wait on a response from Redis, so the
+// subscription may not be active immediately. To force the connection to wait,
+// you may call the Receive() method on the returned *PubSub like so:
+//
+//    sub := client.Subscribe(queryResp)
+//    iface, err := sub.Receive()
+//    if err != nil {
+//        // handle error
+//    }
+//
+//    // Should be *Subscription, but others are possible if other actions have been
+//    // taken on sub since it was created.
+//    switch iface.(type) {
+//    case *Subscription:
+//        // subscribe succeeded
+//    case *Message:
+//        // received first message
+//    case *Pong:
+//        // pong received
+//    default:
+//        // handle error
+//    }
+//
+//    ch := sub.Channel()
+func (c *Client) Subscribe(channels ...string) *PubSub {
+	pubsub := c.pubSub()
+	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 *Client) PSubscribe(channels ...string) *PubSub {
+	pubsub := c.pubSub()
+	if len(channels) > 0 {
+		_ = pubsub.PSubscribe(channels...)
+	}
+	return pubsub
+}
+
+//------------------------------------------------------------------------------
+
+// Conn is like Client, but its pool contains single connection.
+type Conn struct {
+	baseClient
+	statefulCmdable
+}
+
+func newConn(opt *Options, cn *pool.Conn) *Conn {
+	c := Conn{
+		baseClient: baseClient{
+			opt:      opt,
+			connPool: pool.NewSingleConnPool(cn),
+		},
+	}
+	c.baseClient.init()
+	c.statefulCmdable.setProcessor(c.Process)
+	return &c
+}
+
+func (c *Conn) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.Pipeline().Pipelined(fn)
+}
+
+func (c *Conn) Pipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processPipeline,
+	}
+	pipe.statefulCmdable.setProcessor(pipe.Process)
+	return &pipe
+}
+
+func (c *Conn) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.TxPipeline().Pipelined(fn)
+}
+
+// TxPipeline acts like Pipeline, but wraps queued commands with MULTI/EXEC.
+func (c *Conn) TxPipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processTxPipeline,
+	}
+	pipe.statefulCmdable.setProcessor(pipe.Process)
+	return &pipe
+}

vendor/github.com/go-redis/redis/result.go

@@ -0,0 +1,140 @@
+package redis
+
+import "time"
+
+// NewCmdResult returns a Cmd initialised with val and err for testing
+func NewCmdResult(val interface{}, err error) *Cmd {
+	var cmd Cmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewSliceResult returns a SliceCmd initialised with val and err for testing
+func NewSliceResult(val []interface{}, err error) *SliceCmd {
+	var cmd SliceCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewStatusResult returns a StatusCmd initialised with val and err for testing
+func NewStatusResult(val string, err error) *StatusCmd {
+	var cmd StatusCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewIntResult returns an IntCmd initialised with val and err for testing
+func NewIntResult(val int64, err error) *IntCmd {
+	var cmd IntCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewDurationResult returns a DurationCmd initialised with val and err for testing
+func NewDurationResult(val time.Duration, err error) *DurationCmd {
+	var cmd DurationCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewBoolResult returns a BoolCmd initialised with val and err for testing
+func NewBoolResult(val bool, err error) *BoolCmd {
+	var cmd BoolCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewStringResult returns a StringCmd initialised with val and err for testing
+func NewStringResult(val string, err error) *StringCmd {
+	var cmd StringCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewFloatResult returns a FloatCmd initialised with val and err for testing
+func NewFloatResult(val float64, err error) *FloatCmd {
+	var cmd FloatCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewStringSliceResult returns a StringSliceCmd initialised with val and err for testing
+func NewStringSliceResult(val []string, err error) *StringSliceCmd {
+	var cmd StringSliceCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewBoolSliceResult returns a BoolSliceCmd initialised with val and err for testing
+func NewBoolSliceResult(val []bool, err error) *BoolSliceCmd {
+	var cmd BoolSliceCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewStringStringMapResult returns a StringStringMapCmd initialised with val and err for testing
+func NewStringStringMapResult(val map[string]string, err error) *StringStringMapCmd {
+	var cmd StringStringMapCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewStringIntMapCmdResult returns a StringIntMapCmd initialised with val and err for testing
+func NewStringIntMapCmdResult(val map[string]int64, err error) *StringIntMapCmd {
+	var cmd StringIntMapCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewZSliceCmdResult returns a ZSliceCmd initialised with val and err for testing
+func NewZSliceCmdResult(val []Z, err error) *ZSliceCmd {
+	var cmd ZSliceCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewScanCmdResult returns a ScanCmd initialised with val and err for testing
+func NewScanCmdResult(keys []string, cursor uint64, err error) *ScanCmd {
+	var cmd ScanCmd
+	cmd.page = keys
+	cmd.cursor = cursor
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewClusterSlotsCmdResult returns a ClusterSlotsCmd initialised with val and err for testing
+func NewClusterSlotsCmdResult(val []ClusterSlot, err error) *ClusterSlotsCmd {
+	var cmd ClusterSlotsCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewGeoLocationCmdResult returns a GeoLocationCmd initialised with val and err for testing
+func NewGeoLocationCmdResult(val []GeoLocation, err error) *GeoLocationCmd {
+	var cmd GeoLocationCmd
+	cmd.locations = val
+	cmd.setErr(err)
+	return &cmd
+}
+
+// NewCommandsInfoCmdResult returns a CommandsInfoCmd initialised with val and err for testing
+func NewCommandsInfoCmdResult(val map[string]*CommandInfo, err error) *CommandsInfoCmd {
+	var cmd CommandsInfoCmd
+	cmd.val = val
+	cmd.setErr(err)
+	return &cmd
+}

vendor/github.com/go-redis/redis/ring.go

@@ -0,0 +1,658 @@
+package redis
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"math/rand"
+	"strconv"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/go-redis/redis/internal"
+	"github.com/go-redis/redis/internal/consistenthash"
+	"github.com/go-redis/redis/internal/hashtag"
+	"github.com/go-redis/redis/internal/pool"
+)
+
+// Hash is type of hash function used in consistent hash.
+type Hash consistenthash.Hash
+
+var errRingShardsDown = errors.New("redis: all ring shards are down")
+
+// RingOptions are used to configure a ring client and should be
+// passed to NewRing.
+type RingOptions struct {
+	// Map of name => host:port addresses of ring shards.
+	Addrs map[string]string
+
+	// Frequency of PING commands sent to check shards availability.
+	// Shard is considered down after 3 subsequent failed checks.
+	HeartbeatFrequency time.Duration
+
+	// Hash function used in consistent hash.
+	// Default is crc32.ChecksumIEEE.
+	Hash Hash
+
+	// Number of replicas in consistent hash.
+	// Default is 100 replicas.
+	//
+	// Higher number of replicas will provide less deviation, that is keys will be
+	// distributed to nodes more evenly.
+	//
+	// Following is deviation for common nreplicas:
+	//  --------------------------------------------------------
+	//  | nreplicas | standard error | 99% confidence interval |
+	//  |     10    |     0.3152     |      (0.37, 1.98)       |
+	//  |    100    |     0.0997     |      (0.76, 1.28)       |
+	//  |   1000    |     0.0316     |      (0.92, 1.09)       |
+	//  --------------------------------------------------------
+	//
+	//  See https://arxiv.org/abs/1406.2294 for reference
+	HashReplicas int
+
+	// Following options are copied from Options struct.
+
+	OnConnect func(*Conn) error
+
+	DB       int
+	Password string
+
+	MaxRetries      int
+	MinRetryBackoff time.Duration
+	MaxRetryBackoff time.Duration
+
+	DialTimeout  time.Duration
+	ReadTimeout  time.Duration
+	WriteTimeout time.Duration
+
+	PoolSize           int
+	MinIdleConns       int
+	MaxConnAge         time.Duration
+	PoolTimeout        time.Duration
+	IdleTimeout        time.Duration
+	IdleCheckFrequency time.Duration
+}
+
+func (opt *RingOptions) init() {
+	if opt.HeartbeatFrequency == 0 {
+		opt.HeartbeatFrequency = 500 * time.Millisecond
+	}
+
+	if opt.HashReplicas == 0 {
+		opt.HashReplicas = 100
+	}
+
+	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 *RingOptions) clientOptions() *Options {
+	return &Options{
+		OnConnect: opt.OnConnect,
+
+		DB:       opt.DB,
+		Password: opt.Password,
+
+		DialTimeout:  opt.DialTimeout,
+		ReadTimeout:  opt.ReadTimeout,
+		WriteTimeout: opt.WriteTimeout,
+
+		PoolSize:           opt.PoolSize,
+		MinIdleConns:       opt.MinIdleConns,
+		MaxConnAge:         opt.MaxConnAge,
+		PoolTimeout:        opt.PoolTimeout,
+		IdleTimeout:        opt.IdleTimeout,
+		IdleCheckFrequency: opt.IdleCheckFrequency,
+	}
+}
+
+//------------------------------------------------------------------------------
+
+type ringShard struct {
+	Client *Client
+	down   int32
+}
+
+func (shard *ringShard) String() string {
+	var state string
+	if shard.IsUp() {
+		state = "up"
+	} else {
+		state = "down"
+	}
+	return fmt.Sprintf("%s is %s", shard.Client, state)
+}
+
+func (shard *ringShard) IsDown() bool {
+	const threshold = 3
+	return atomic.LoadInt32(&shard.down) >= threshold
+}
+
+func (shard *ringShard) IsUp() bool {
+	return !shard.IsDown()
+}
+
+// Vote votes to set shard state and returns true if state was changed.
+func (shard *ringShard) Vote(up bool) bool {
+	if up {
+		changed := shard.IsDown()
+		atomic.StoreInt32(&shard.down, 0)
+		return changed
+	}
+
+	if shard.IsDown() {
+		return false
+	}
+
+	atomic.AddInt32(&shard.down, 1)
+	return shard.IsDown()
+}
+
+//------------------------------------------------------------------------------
+
+type ringShards struct {
+	opt *RingOptions
+
+	mu     sync.RWMutex
+	hash   *consistenthash.Map
+	shards map[string]*ringShard // read only
+	list   []*ringShard          // read only
+	len    int
+	closed bool
+}
+
+func newRingShards(opt *RingOptions) *ringShards {
+	return &ringShards{
+		opt: opt,
+
+		hash:   newConsistentHash(opt),
+		shards: make(map[string]*ringShard),
+	}
+}
+
+func (c *ringShards) Add(name string, cl *Client) {
+	shard := &ringShard{Client: cl}
+	c.hash.Add(name)
+	c.shards[name] = shard
+	c.list = append(c.list, shard)
+}
+
+func (c *ringShards) List() []*ringShard {
+	c.mu.RLock()
+	list := c.list
+	c.mu.RUnlock()
+	return list
+}
+
+func (c *ringShards) Hash(key string) string {
+	c.mu.RLock()
+	hash := c.hash.Get(key)
+	c.mu.RUnlock()
+	return hash
+}
+
+func (c *ringShards) GetByKey(key string) (*ringShard, error) {
+	key = hashtag.Key(key)
+
+	c.mu.RLock()
+
+	if c.closed {
+		c.mu.RUnlock()
+		return nil, pool.ErrClosed
+	}
+
+	hash := c.hash.Get(key)
+	if hash == "" {
+		c.mu.RUnlock()
+		return nil, errRingShardsDown
+	}
+
+	shard := c.shards[hash]
+	c.mu.RUnlock()
+
+	return shard, nil
+}
+
+func (c *ringShards) GetByHash(name string) (*ringShard, error) {
+	if name == "" {
+		return c.Random()
+	}
+
+	c.mu.RLock()
+	shard := c.shards[name]
+	c.mu.RUnlock()
+	return shard, nil
+}
+
+func (c *ringShards) Random() (*ringShard, error) {
+	return c.GetByKey(strconv.Itoa(rand.Int()))
+}
+
+// heartbeat monitors state of each shard in the ring.
+func (c *ringShards) Heartbeat(frequency time.Duration) {
+	ticker := time.NewTicker(frequency)
+	defer ticker.Stop()
+	for range ticker.C {
+		var rebalance bool
+
+		c.mu.RLock()
+
+		if c.closed {
+			c.mu.RUnlock()
+			break
+		}
+
+		shards := c.list
+		c.mu.RUnlock()
+
+		for _, shard := range shards {
+			err := shard.Client.Ping().Err()
+			if shard.Vote(err == nil || err == pool.ErrPoolTimeout) {
+				internal.Logf("ring shard state changed: %s", shard)
+				rebalance = true
+			}
+		}
+
+		if rebalance {
+			c.rebalance()
+		}
+	}
+}
+
+// rebalance removes dead shards from the Ring.
+func (c *ringShards) rebalance() {
+	hash := newConsistentHash(c.opt)
+	var shardsNum int
+	for name, shard := range c.shards {
+		if shard.IsUp() {
+			hash.Add(name)
+			shardsNum++
+		}
+	}
+
+	c.mu.Lock()
+	c.hash = hash
+	c.len = shardsNum
+	c.mu.Unlock()
+}
+
+func (c *ringShards) Len() int {
+	c.mu.RLock()
+	l := c.len
+	c.mu.RUnlock()
+	return l
+}
+
+func (c *ringShards) Close() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	if c.closed {
+		return nil
+	}
+	c.closed = true
+
+	var firstErr error
+	for _, shard := range c.shards {
+		if err := shard.Client.Close(); err != nil && firstErr == nil {
+			firstErr = err
+		}
+	}
+	c.hash = nil
+	c.shards = nil
+	c.list = nil
+
+	return firstErr
+}
+
+//------------------------------------------------------------------------------
+
+// Ring is a Redis client that uses consistent hashing to distribute
+// keys across multiple Redis servers (shards). It's safe for
+// concurrent use by multiple goroutines.
+//
+// Ring monitors the state of each shard and removes dead shards from
+// the ring. When a shard comes online it is added back to the ring. This
+// gives you maximum availability and partition tolerance, but no
+// consistency between different shards or even clients. Each client
+// uses shards that are available to the client and does not do any
+// coordination when shard state is changed.
+//
+// Ring should be used when you need multiple Redis servers for caching
+// and can tolerate losing data when one of the servers dies.
+// Otherwise you should use Redis Cluster.
+type Ring struct {
+	cmdable
+
+	ctx context.Context
+
+	opt           *RingOptions
+	shards        *ringShards
+	cmdsInfoCache *cmdsInfoCache
+
+	process         func(Cmder) error
+	processPipeline func([]Cmder) error
+}
+
+func NewRing(opt *RingOptions) *Ring {
+	opt.init()
+
+	ring := &Ring{
+		opt:    opt,
+		shards: newRingShards(opt),
+	}
+	ring.cmdsInfoCache = newCmdsInfoCache(ring.cmdsInfo)
+
+	ring.process = ring.defaultProcess
+	ring.processPipeline = ring.defaultProcessPipeline
+	ring.cmdable.setProcessor(ring.Process)
+
+	for name, addr := range opt.Addrs {
+		clopt := opt.clientOptions()
+		clopt.Addr = addr
+		ring.shards.Add(name, NewClient(clopt))
+	}
+
+	go ring.shards.Heartbeat(opt.HeartbeatFrequency)
+
+	return ring
+}
+
+func (c *Ring) Context() context.Context {
+	if c.ctx != nil {
+		return c.ctx
+	}
+	return context.Background()
+}
+
+func (c *Ring) WithContext(ctx context.Context) *Ring {
+	if ctx == nil {
+		panic("nil context")
+	}
+	c2 := c.copy()
+	c2.ctx = ctx
+	return c2
+}
+
+func (c *Ring) copy() *Ring {
+	cp := *c
+	return &cp
+}
+
+// Options returns read-only Options that were used to create the client.
+func (c *Ring) Options() *RingOptions {
+	return c.opt
+}
+
+func (c *Ring) retryBackoff(attempt int) time.Duration {
+	return internal.RetryBackoff(attempt, c.opt.MinRetryBackoff, c.opt.MaxRetryBackoff)
+}
+
+// PoolStats returns accumulated connection pool stats.
+func (c *Ring) PoolStats() *PoolStats {
+	shards := c.shards.List()
+	var acc PoolStats
+	for _, shard := range shards {
+		s := shard.Client.connPool.Stats()
+		acc.Hits += s.Hits
+		acc.Misses += s.Misses
+		acc.Timeouts += s.Timeouts
+		acc.TotalConns += s.TotalConns
+		acc.IdleConns += s.IdleConns
+	}
+	return &acc
+}
+
+// Len returns the current number of shards in the ring.
+func (c *Ring) Len() int {
+	return c.shards.Len()
+}
+
+// Subscribe subscribes the client to the specified channels.
+func (c *Ring) Subscribe(channels ...string) *PubSub {
+	if len(channels) == 0 {
+		panic("at least one channel is required")
+	}
+
+	shard, err := c.shards.GetByKey(channels[0])
+	if err != nil {
+		// TODO: return PubSub with sticky error
+		panic(err)
+	}
+	return shard.Client.Subscribe(channels...)
+}
+
+// PSubscribe subscribes the client to the given patterns.
+func (c *Ring) PSubscribe(channels ...string) *PubSub {
+	if len(channels) == 0 {
+		panic("at least one channel is required")
+	}
+
+	shard, err := c.shards.GetByKey(channels[0])
+	if err != nil {
+		// TODO: return PubSub with sticky error
+		panic(err)
+	}
+	return shard.Client.PSubscribe(channels...)
+}
+
+// ForEachShard concurrently calls the fn on each live shard in the ring.
+// It returns the first error if any.
+func (c *Ring) ForEachShard(fn func(client *Client) error) error {
+	shards := c.shards.List()
+	var wg sync.WaitGroup
+	errCh := make(chan error, 1)
+	for _, shard := range shards {
+		if shard.IsDown() {
+			continue
+		}
+
+		wg.Add(1)
+		go func(shard *ringShard) {
+			defer wg.Done()
+			err := fn(shard.Client)
+			if err != nil {
+				select {
+				case errCh <- err:
+				default:
+				}
+			}
+		}(shard)
+	}
+	wg.Wait()
+
+	select {
+	case err := <-errCh:
+		return err
+	default:
+		return nil
+	}
+}
+
+func (c *Ring) cmdsInfo() (map[string]*CommandInfo, error) {
+	shards := c.shards.List()
+	firstErr := errRingShardsDown
+	for _, shard := range shards {
+		cmdsInfo, err := shard.Client.Command().Result()
+		if err == nil {
+			return cmdsInfo, nil
+		}
+		if firstErr == nil {
+			firstErr = err
+		}
+	}
+	return nil, firstErr
+}
+
+func (c *Ring) 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 (c *Ring) cmdShard(cmd Cmder) (*ringShard, error) {
+	cmdInfo := c.cmdInfo(cmd.Name())
+	pos := cmdFirstKeyPos(cmd, cmdInfo)
+	if pos == 0 {
+		return c.shards.Random()
+	}
+	firstKey := cmd.stringArg(pos)
+	return c.shards.GetByKey(firstKey)
+}
+
+// Do creates a Cmd from the args and processes the cmd.
+func (c *Ring) Do(args ...interface{}) *Cmd {
+	cmd := NewCmd(args...)
+	c.Process(cmd)
+	return cmd
+}
+
+func (c *Ring) WrapProcess(
+	fn func(oldProcess func(cmd Cmder) error) func(cmd Cmder) error,
+) {
+	c.process = fn(c.process)
+}
+
+func (c *Ring) Process(cmd Cmder) error {
+	return c.process(cmd)
+}
+
+func (c *Ring) defaultProcess(cmd Cmder) error {
+	for attempt := 0; attempt <= c.opt.MaxRetries; attempt++ {
+		if attempt > 0 {
+			time.Sleep(c.retryBackoff(attempt))
+		}
+
+		shard, err := c.cmdShard(cmd)
+		if err != nil {
+			cmd.setErr(err)
+			return err
+		}
+
+		err = shard.Client.Process(cmd)
+		if err == nil {
+			return nil
+		}
+		if !internal.IsRetryableError(err, cmd.readTimeout() == nil) {
+			return err
+		}
+	}
+	return cmd.Err()
+}
+
+func (c *Ring) Pipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processPipeline,
+	}
+	pipe.cmdable.setProcessor(pipe.Process)
+	return &pipe
+}
+
+func (c *Ring) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.Pipeline().Pipelined(fn)
+}
+
+func (c *Ring) WrapProcessPipeline(
+	fn func(oldProcess func([]Cmder) error) func([]Cmder) error,
+) {
+	c.processPipeline = fn(c.processPipeline)
+}
+
+func (c *Ring) defaultProcessPipeline(cmds []Cmder) error {
+	cmdsMap := make(map[string][]Cmder)
+	for _, cmd := range cmds {
+		cmdInfo := c.cmdInfo(cmd.Name())
+		hash := cmd.stringArg(cmdFirstKeyPos(cmd, cmdInfo))
+		if hash != "" {
+			hash = c.shards.Hash(hashtag.Key(hash))
+		}
+		cmdsMap[hash] = append(cmdsMap[hash], cmd)
+	}
+
+	for attempt := 0; attempt <= c.opt.MaxRetries; attempt++ {
+		if attempt > 0 {
+			time.Sleep(c.retryBackoff(attempt))
+		}
+
+		var mu sync.Mutex
+		var failedCmdsMap map[string][]Cmder
+		var wg sync.WaitGroup
+
+		for hash, cmds := range cmdsMap {
+			wg.Add(1)
+			go func(hash string, cmds []Cmder) {
+				defer wg.Done()
+
+				shard, err := c.shards.GetByHash(hash)
+				if err != nil {
+					setCmdsErr(cmds, err)
+					return
+				}
+
+				cn, err := shard.Client.getConn()
+				if err != nil {
+					setCmdsErr(cmds, err)
+					return
+				}
+
+				canRetry, err := shard.Client.pipelineProcessCmds(cn, cmds)
+				shard.Client.releaseConnStrict(cn, err)
+
+				if canRetry && internal.IsRetryableError(err, true) {
+					mu.Lock()
+					if failedCmdsMap == nil {
+						failedCmdsMap = make(map[string][]Cmder)
+					}
+					failedCmdsMap[hash] = cmds
+					mu.Unlock()
+				}
+			}(hash, cmds)
+		}
+
+		wg.Wait()
+		if len(failedCmdsMap) == 0 {
+			break
+		}
+		cmdsMap = failedCmdsMap
+	}
+
+	return cmdsFirstErr(cmds)
+}
+
+func (c *Ring) TxPipeline() Pipeliner {
+	panic("not implemented")
+}
+
+func (c *Ring) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	panic("not implemented")
+}
+
+// Close closes the ring client, releasing any open resources.
+//
+// It is rare to Close a Ring, as the Ring is meant to be long-lived
+// and shared between many goroutines.
+func (c *Ring) Close() error {
+	return c.shards.Close()
+}
+
+func newConsistentHash(opt *RingOptions) *consistenthash.Map {
+	return consistenthash.New(opt.HashReplicas, consistenthash.Hash(opt.Hash))
+}

vendor/github.com/go-redis/redis/script.go

@@ -0,0 +1,62 @@
+package redis
+
+import (
+	"crypto/sha1"
+	"encoding/hex"
+	"io"
+	"strings"
+)
+
+type scripter interface {
+	Eval(script string, keys []string, args ...interface{}) *Cmd
+	EvalSha(sha1 string, keys []string, args ...interface{}) *Cmd
+	ScriptExists(hashes ...string) *BoolSliceCmd
+	ScriptLoad(script string) *StringCmd
+}
+
+var _ scripter = (*Client)(nil)
+var _ scripter = (*Ring)(nil)
+var _ scripter = (*ClusterClient)(nil)
+
+type Script struct {
+	src, hash string
+}
+
+func NewScript(src string) *Script {
+	h := sha1.New()
+	io.WriteString(h, src)
+	return &Script{
+		src:  src,
+		hash: hex.EncodeToString(h.Sum(nil)),
+	}
+}
+
+func (s *Script) Hash() string {
+	return s.hash
+}
+
+func (s *Script) Load(c scripter) *StringCmd {
+	return c.ScriptLoad(s.src)
+}
+
+func (s *Script) Exists(c scripter) *BoolSliceCmd {
+	return c.ScriptExists(s.hash)
+}
+
+func (s *Script) Eval(c scripter, keys []string, args ...interface{}) *Cmd {
+	return c.Eval(s.src, keys, args...)
+}
+
+func (s *Script) EvalSha(c scripter, keys []string, args ...interface{}) *Cmd {
+	return c.EvalSha(s.hash, keys, args...)
+}
+
+// Run optimistically uses EVALSHA to run the script. If script does not exist
+// it is retried using EVAL.
+func (s *Script) Run(c scripter, keys []string, args ...interface{}) *Cmd {
+	r := s.EvalSha(c, keys, args...)
+	if err := r.Err(); err != nil && strings.HasPrefix(err.Error(), "NOSCRIPT ") {
+		return s.Eval(c, keys, args...)
+	}
+	return r
+}

vendor/github.com/go-redis/redis/sentinel.go

@@ -0,0 +1,399 @@
+package redis
+
+import (
+	"crypto/tls"
+	"errors"
+	"net"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/go-redis/redis/internal"
+	"github.com/go-redis/redis/internal/pool"
+)
+
+//------------------------------------------------------------------------------
+
+// FailoverOptions are used to configure a failover client and should
+// be passed to NewFailoverClient.
+type FailoverOptions struct {
+	// The master name.
+	MasterName string
+	// A seed list of host:port addresses of sentinel nodes.
+	SentinelAddrs []string
+
+	// Following options are copied from Options struct.
+
+	OnConnect func(*Conn) error
+
+	Password string
+	DB       int
+
+	MaxRetries      int
+	MinRetryBackoff time.Duration
+	MaxRetryBackoff time.Duration
+
+	DialTimeout  time.Duration
+	ReadTimeout  time.Duration
+	WriteTimeout time.Duration
+
+	PoolSize           int
+	MinIdleConns       int
+	MaxConnAge         time.Duration
+	PoolTimeout        time.Duration
+	IdleTimeout        time.Duration
+	IdleCheckFrequency time.Duration
+
+	TLSConfig *tls.Config
+}
+
+func (opt *FailoverOptions) options() *Options {
+	return &Options{
+		Addr: "FailoverClient",
+
+		OnConnect: opt.OnConnect,
+
+		DB:       opt.DB,
+		Password: opt.Password,
+
+		MaxRetries: opt.MaxRetries,
+
+		DialTimeout:  opt.DialTimeout,
+		ReadTimeout:  opt.ReadTimeout,
+		WriteTimeout: opt.WriteTimeout,
+
+		PoolSize:           opt.PoolSize,
+		PoolTimeout:        opt.PoolTimeout,
+		IdleTimeout:        opt.IdleTimeout,
+		IdleCheckFrequency: opt.IdleCheckFrequency,
+
+		TLSConfig: opt.TLSConfig,
+	}
+}
+
+// NewFailoverClient returns a Redis client that uses Redis Sentinel
+// for automatic failover. It's safe for concurrent use by multiple
+// goroutines.
+func NewFailoverClient(failoverOpt *FailoverOptions) *Client {
+	opt := failoverOpt.options()
+	opt.init()
+
+	failover := &sentinelFailover{
+		masterName:    failoverOpt.MasterName,
+		sentinelAddrs: failoverOpt.SentinelAddrs,
+
+		opt: opt,
+	}
+
+	c := Client{
+		baseClient: baseClient{
+			opt:      opt,
+			connPool: failover.Pool(),
+
+			onClose: func() error {
+				return failover.Close()
+			},
+		},
+	}
+	c.baseClient.init()
+	c.cmdable.setProcessor(c.Process)
+
+	return &c
+}
+
+//------------------------------------------------------------------------------
+
+type SentinelClient struct {
+	baseClient
+}
+
+func NewSentinelClient(opt *Options) *SentinelClient {
+	opt.init()
+	c := &SentinelClient{
+		baseClient: baseClient{
+			opt:      opt,
+			connPool: newConnPool(opt),
+		},
+	}
+	c.baseClient.init()
+	return c
+}
+
+func (c *SentinelClient) pubSub() *PubSub {
+	pubsub := &PubSub{
+		opt: c.opt,
+
+		newConn: func(channels []string) (*pool.Conn, error) {
+			return c.newConn()
+		},
+		closeConn: c.connPool.CloseConn,
+	}
+	pubsub.init()
+	return pubsub
+}
+
+// Subscribe subscribes the client to the specified channels.
+// Channels can be omitted to create empty subscription.
+func (c *SentinelClient) Subscribe(channels ...string) *PubSub {
+	pubsub := c.pubSub()
+	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 *SentinelClient) PSubscribe(channels ...string) *PubSub {
+	pubsub := c.pubSub()
+	if len(channels) > 0 {
+		_ = pubsub.PSubscribe(channels...)
+	}
+	return pubsub
+}
+
+func (c *SentinelClient) GetMasterAddrByName(name string) *StringSliceCmd {
+	cmd := NewStringSliceCmd("sentinel", "get-master-addr-by-name", name)
+	c.Process(cmd)
+	return cmd
+}
+
+func (c *SentinelClient) Sentinels(name string) *SliceCmd {
+	cmd := NewSliceCmd("sentinel", "sentinels", name)
+	c.Process(cmd)
+	return cmd
+}
+
+// Failover forces a failover as if the master was not reachable, and without
+// asking for agreement to other Sentinels.
+func (c *SentinelClient) Failover(name string) *StatusCmd {
+	cmd := NewStatusCmd("sentinel", "failover", name)
+	c.Process(cmd)
+	return cmd
+}
+
+// Reset resets all the masters with matching name. The pattern argument is a
+// glob-style pattern. The reset process clears any previous state in a master
+// (including a failover in progress), and removes every slave and sentinel
+// already discovered and associated with the master.
+func (c *SentinelClient) Reset(pattern string) *IntCmd {
+	cmd := NewIntCmd("sentinel", "reset", pattern)
+	c.Process(cmd)
+	return cmd
+}
+
+type sentinelFailover struct {
+	sentinelAddrs []string
+
+	opt *Options
+
+	pool     *pool.ConnPool
+	poolOnce sync.Once
+
+	mu          sync.RWMutex
+	masterName  string
+	_masterAddr string
+	sentinel    *SentinelClient
+	pubsub      *PubSub
+}
+
+func (c *sentinelFailover) Close() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.sentinel != nil {
+		return c.closeSentinel()
+	}
+	return nil
+}
+
+func (c *sentinelFailover) Pool() *pool.ConnPool {
+	c.poolOnce.Do(func() {
+		c.opt.Dialer = c.dial
+		c.pool = newConnPool(c.opt)
+	})
+	return c.pool
+}
+
+func (c *sentinelFailover) dial() (net.Conn, error) {
+	addr, err := c.MasterAddr()
+	if err != nil {
+		return nil, err
+	}
+	return net.DialTimeout("tcp", addr, c.opt.DialTimeout)
+}
+
+func (c *sentinelFailover) MasterAddr() (string, error) {
+	addr, err := c.masterAddr()
+	if err != nil {
+		return "", err
+	}
+	c.switchMaster(addr)
+	return addr, nil
+}
+
+func (c *sentinelFailover) masterAddr() (string, error) {
+	addr := c.getMasterAddr()
+	if addr != "" {
+		return addr, nil
+	}
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	for i, sentinelAddr := range c.sentinelAddrs {
+		sentinel := NewSentinelClient(&Options{
+			Addr: sentinelAddr,
+
+			MaxRetries: c.opt.MaxRetries,
+
+			DialTimeout:  c.opt.DialTimeout,
+			ReadTimeout:  c.opt.ReadTimeout,
+			WriteTimeout: c.opt.WriteTimeout,
+
+			PoolSize:           c.opt.PoolSize,
+			PoolTimeout:        c.opt.PoolTimeout,
+			IdleTimeout:        c.opt.IdleTimeout,
+			IdleCheckFrequency: c.opt.IdleCheckFrequency,
+
+			TLSConfig: c.opt.TLSConfig,
+		})
+
+		masterAddr, err := sentinel.GetMasterAddrByName(c.masterName).Result()
+		if err != nil {
+			internal.Logf("sentinel: GetMasterAddrByName master=%q failed: %s",
+				c.masterName, err)
+			_ = sentinel.Close()
+			continue
+		}
+
+		// Push working sentinel to the top.
+		c.sentinelAddrs[0], c.sentinelAddrs[i] = c.sentinelAddrs[i], c.sentinelAddrs[0]
+		c.setSentinel(sentinel)
+
+		addr := net.JoinHostPort(masterAddr[0], masterAddr[1])
+		return addr, nil
+	}
+
+	return "", errors.New("redis: all sentinels are unreachable")
+}
+
+func (c *sentinelFailover) getMasterAddr() string {
+	c.mu.RLock()
+	sentinel := c.sentinel
+	c.mu.RUnlock()
+
+	if sentinel == nil {
+		return ""
+	}
+
+	addr, err := sentinel.GetMasterAddrByName(c.masterName).Result()
+	if err != nil {
+		internal.Logf("sentinel: GetMasterAddrByName name=%q failed: %s",
+			c.masterName, err)
+		c.mu.Lock()
+		if c.sentinel == sentinel {
+			c.closeSentinel()
+		}
+		c.mu.Unlock()
+		return ""
+	}
+
+	return net.JoinHostPort(addr[0], addr[1])
+}
+
+func (c *sentinelFailover) switchMaster(addr string) {
+	c.mu.RLock()
+	masterAddr := c._masterAddr
+	c.mu.RUnlock()
+	if masterAddr == addr {
+		return
+	}
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	internal.Logf("sentinel: new master=%q addr=%q",
+		c.masterName, addr)
+	_ = c.Pool().Filter(func(cn *pool.Conn) bool {
+		return cn.RemoteAddr().String() != addr
+	})
+	c._masterAddr = addr
+}
+
+func (c *sentinelFailover) setSentinel(sentinel *SentinelClient) {
+	c.discoverSentinels(sentinel)
+	c.sentinel = sentinel
+
+	c.pubsub = sentinel.Subscribe("+switch-master")
+	go c.listen(c.pubsub)
+}
+
+func (c *sentinelFailover) closeSentinel() error {
+	var firstErr error
+
+	err := c.pubsub.Close()
+	if err != nil && firstErr == err {
+		firstErr = err
+	}
+	c.pubsub = nil
+
+	err = c.sentinel.Close()
+	if err != nil && firstErr == err {
+		firstErr = err
+	}
+	c.sentinel = nil
+
+	return firstErr
+}
+
+func (c *sentinelFailover) discoverSentinels(sentinel *SentinelClient) {
+	sentinels, err := sentinel.Sentinels(c.masterName).Result()
+	if err != nil {
+		internal.Logf("sentinel: Sentinels master=%q failed: %s", c.masterName, err)
+		return
+	}
+	for _, sentinel := range sentinels {
+		vals := sentinel.([]interface{})
+		for i := 0; i < len(vals); i += 2 {
+			key := vals[i].(string)
+			if key == "name" {
+				sentinelAddr := vals[i+1].(string)
+				if !contains(c.sentinelAddrs, sentinelAddr) {
+					internal.Logf("sentinel: discovered new sentinel=%q for master=%q",
+						sentinelAddr, c.masterName)
+					c.sentinelAddrs = append(c.sentinelAddrs, sentinelAddr)
+				}
+			}
+		}
+	}
+}
+
+func (c *sentinelFailover) listen(pubsub *PubSub) {
+	ch := pubsub.Channel()
+	for {
+		msg, ok := <-ch
+		if !ok {
+			break
+		}
+
+		switch msg.Channel {
+		case "+switch-master":
+			parts := strings.Split(msg.Payload, " ")
+			if parts[0] != c.masterName {
+				internal.Logf("sentinel: ignore addr for master=%q", parts[0])
+				continue
+			}
+			addr := net.JoinHostPort(parts[3], parts[4])
+			c.switchMaster(addr)
+		}
+	}
+}
+
+func contains(slice []string, str string) bool {
+	for _, s := range slice {
+		if s == str {
+			return true
+		}
+	}
+	return false
+}

vendor/github.com/go-redis/redis/tx.go

@@ -0,0 +1,110 @@
+package redis
+
+import (
+	"github.com/go-redis/redis/internal/pool"
+	"github.com/go-redis/redis/internal/proto"
+)
+
+// TxFailedErr transaction redis failed.
+const TxFailedErr = proto.RedisError("redis: transaction failed")
+
+// Tx implements Redis transactions as described in
+// http://redis.io/topics/transactions. It's NOT safe for concurrent use
+// by multiple goroutines, because Exec resets list of watched keys.
+// If you don't need WATCH it is better to use Pipeline.
+type Tx struct {
+	statefulCmdable
+	baseClient
+}
+
+func (c *Client) newTx() *Tx {
+	tx := Tx{
+		baseClient: baseClient{
+			opt:      c.opt,
+			connPool: pool.NewStickyConnPool(c.connPool.(*pool.ConnPool), true),
+		},
+	}
+	tx.baseClient.init()
+	tx.statefulCmdable.setProcessor(tx.Process)
+	return &tx
+}
+
+// Watch prepares a transaction and marks the keys to be watched
+// for conditional execution if there are any keys.
+//
+// The transaction is automatically closed when fn exits.
+func (c *Client) Watch(fn func(*Tx) error, keys ...string) error {
+	tx := c.newTx()
+	if len(keys) > 0 {
+		if err := tx.Watch(keys...).Err(); err != nil {
+			_ = tx.Close()
+			return err
+		}
+	}
+
+	err := fn(tx)
+	_ = tx.Close()
+	return err
+}
+
+// Close closes the transaction, releasing any open resources.
+func (c *Tx) Close() error {
+	_ = c.Unwatch().Err()
+	return c.baseClient.Close()
+}
+
+// Watch marks the keys to be watched for conditional execution
+// of a transaction.
+func (c *Tx) Watch(keys ...string) *StatusCmd {
+	args := make([]interface{}, 1+len(keys))
+	args[0] = "watch"
+	for i, key := range keys {
+		args[1+i] = key
+	}
+	cmd := NewStatusCmd(args...)
+	c.Process(cmd)
+	return cmd
+}
+
+// Unwatch flushes all the previously watched keys for a transaction.
+func (c *Tx) Unwatch(keys ...string) *StatusCmd {
+	args := make([]interface{}, 1+len(keys))
+	args[0] = "unwatch"
+	for i, key := range keys {
+		args[1+i] = key
+	}
+	cmd := NewStatusCmd(args...)
+	c.Process(cmd)
+	return cmd
+}
+
+// Pipeline creates a new pipeline. It is more convenient to use Pipelined.
+func (c *Tx) Pipeline() Pipeliner {
+	pipe := Pipeline{
+		exec: c.processTxPipeline,
+	}
+	pipe.statefulCmdable.setProcessor(pipe.Process)
+	return &pipe
+}
+
+// Pipelined executes commands queued in the fn in a transaction.
+//
+// When using WATCH, EXEC will execute commands only if the watched keys
+// were not modified, allowing for a check-and-set mechanism.
+//
+// Exec always returns list of commands. If transaction fails
+// TxFailedErr is returned. Otherwise Exec returns an error of the first
+// failed command or nil.
+func (c *Tx) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.Pipeline().Pipelined(fn)
+}
+
+// TxPipelined is an alias for Pipelined.
+func (c *Tx) TxPipelined(fn func(Pipeliner) error) ([]Cmder, error) {
+	return c.Pipelined(fn)
+}
+
+// TxPipeline is an alias for Pipeline.
+func (c *Tx) TxPipeline() Pipeliner {
+	return c.Pipeline()
+}

vendor/github.com/go-redis/redis/universal.go

@@ -0,0 +1,179 @@
+package redis
+
+import (
+	"crypto/tls"
+	"time"
+)
+
+// UniversalOptions information is required by UniversalClient to establish
+// connections.
+type UniversalOptions struct {
+	// Either a single address or a seed list of host:port addresses
+	// of cluster/sentinel nodes.
+	Addrs []string
+
+	// Database to be selected after connecting to the server.
+	// Only single-node and failover clients.
+	DB int
+
+	// Common options.
+
+	OnConnect          func(*Conn) error
+	Password           string
+	MaxRetries         int
+	MinRetryBackoff    time.Duration
+	MaxRetryBackoff    time.Duration
+	DialTimeout        time.Duration
+	ReadTimeout        time.Duration
+	WriteTimeout       time.Duration
+	PoolSize           int
+	MinIdleConns       int
+	MaxConnAge         time.Duration
+	PoolTimeout        time.Duration
+	IdleTimeout        time.Duration
+	IdleCheckFrequency time.Duration
+	TLSConfig          *tls.Config
+
+	// Only cluster clients.
+
+	MaxRedirects   int
+	ReadOnly       bool
+	RouteByLatency bool
+	RouteRandomly  bool
+
+	// The sentinel master name.
+	// Only failover clients.
+	MasterName string
+}
+
+func (o *UniversalOptions) cluster() *ClusterOptions {
+	if len(o.Addrs) == 0 {
+		o.Addrs = []string{"127.0.0.1:6379"}
+	}
+
+	return &ClusterOptions{
+		Addrs:     o.Addrs,
+		OnConnect: o.OnConnect,
+
+		Password: o.Password,
+
+		MaxRedirects:   o.MaxRedirects,
+		ReadOnly:       o.ReadOnly,
+		RouteByLatency: o.RouteByLatency,
+		RouteRandomly:  o.RouteRandomly,
+
+		MaxRetries:      o.MaxRetries,
+		MinRetryBackoff: o.MinRetryBackoff,
+		MaxRetryBackoff: o.MaxRetryBackoff,
+
+		DialTimeout:        o.DialTimeout,
+		ReadTimeout:        o.ReadTimeout,
+		WriteTimeout:       o.WriteTimeout,
+		PoolSize:           o.PoolSize,
+		MinIdleConns:       o.MinIdleConns,
+		MaxConnAge:         o.MaxConnAge,
+		PoolTimeout:        o.PoolTimeout,
+		IdleTimeout:        o.IdleTimeout,
+		IdleCheckFrequency: o.IdleCheckFrequency,
+
+		TLSConfig: o.TLSConfig,
+	}
+}
+
+func (o *UniversalOptions) failover() *FailoverOptions {
+	if len(o.Addrs) == 0 {
+		o.Addrs = []string{"127.0.0.1:26379"}
+	}
+
+	return &FailoverOptions{
+		SentinelAddrs: o.Addrs,
+		MasterName:    o.MasterName,
+		OnConnect:     o.OnConnect,
+
+		DB:       o.DB,
+		Password: o.Password,
+
+		MaxRetries:      o.MaxRetries,
+		MinRetryBackoff: o.MinRetryBackoff,
+		MaxRetryBackoff: o.MaxRetryBackoff,
+
+		DialTimeout:  o.DialTimeout,
+		ReadTimeout:  o.ReadTimeout,
+		WriteTimeout: o.WriteTimeout,
+
+		PoolSize:           o.PoolSize,
+		MinIdleConns:       o.MinIdleConns,
+		MaxConnAge:         o.MaxConnAge,
+		PoolTimeout:        o.PoolTimeout,
+		IdleTimeout:        o.IdleTimeout,
+		IdleCheckFrequency: o.IdleCheckFrequency,
+
+		TLSConfig: o.TLSConfig,
+	}
+}
+
+func (o *UniversalOptions) simple() *Options {
+	addr := "127.0.0.1:6379"
+	if len(o.Addrs) > 0 {
+		addr = o.Addrs[0]
+	}
+
+	return &Options{
+		Addr:      addr,
+		OnConnect: o.OnConnect,
+
+		DB:       o.DB,
+		Password: o.Password,
+
+		MaxRetries:      o.MaxRetries,
+		MinRetryBackoff: o.MinRetryBackoff,
+		MaxRetryBackoff: o.MaxRetryBackoff,
+
+		DialTimeout:  o.DialTimeout,
+		ReadTimeout:  o.ReadTimeout,
+		WriteTimeout: o.WriteTimeout,
+
+		PoolSize:           o.PoolSize,
+		MinIdleConns:       o.MinIdleConns,
+		MaxConnAge:         o.MaxConnAge,
+		PoolTimeout:        o.PoolTimeout,
+		IdleTimeout:        o.IdleTimeout,
+		IdleCheckFrequency: o.IdleCheckFrequency,
+
+		TLSConfig: o.TLSConfig,
+	}
+}
+
+// --------------------------------------------------------------------
+
+// UniversalClient is an abstract client which - based on the provided options -
+// can connect to either clusters, or sentinel-backed failover instances or simple
+// single-instance servers. This can be useful for testing cluster-specific
+// applications locally.
+type UniversalClient interface {
+	Cmdable
+	Watch(fn func(*Tx) error, keys ...string) error
+	Process(cmd Cmder) error
+	WrapProcess(fn func(oldProcess func(cmd Cmder) error) func(cmd Cmder) error)
+	Subscribe(channels ...string) *PubSub
+	PSubscribe(channels ...string) *PubSub
+	Close() error
+}
+
+var _ UniversalClient = (*Client)(nil)
+var _ UniversalClient = (*ClusterClient)(nil)
+
+// NewUniversalClient returns a new multi client. The type of client returned depends
+// on the following three conditions:
+//
+// 1. if a MasterName is passed a sentinel-backed FailoverClient will be returned
+// 2. if the number of Addrs is two or more, a ClusterClient will be returned
+// 3. otherwise, a single-node redis Client will be returned.
+func NewUniversalClient(opts *UniversalOptions) UniversalClient {
+	if opts.MasterName != "" {
+		return NewFailoverClient(opts.failover())
+	} else if len(opts.Addrs) > 1 {
+		return NewClusterClient(opts.cluster())
+	}
+	return NewClient(opts.simple())
+}

vendor/modules.txt

@@ -143,6 +143,14 @@ github.com/go-macaron/session/postgres
 github.com/go-macaron/session/redis
 # github.com/go-macaron/toolbox v0.0.0-20180818072302-a77f45a7ce90
 github.com/go-macaron/toolbox
+# github.com/go-redis/redis v6.15.2+incompatible
+github.com/go-redis/redis
+github.com/go-redis/redis/internal
+github.com/go-redis/redis/internal/consistenthash
+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/util
 # github.com/go-sql-driver/mysql v1.4.0 => github.com/go-sql-driver/mysql v0.0.0-20181218123637-c45f530f8e7f
 github.com/go-sql-driver/mysql
 # github.com/go-xorm/builder v0.3.3