redis/README.md

4.0 KiB

Readme

Redis client for Golang.

Supports:

  • Redis 2.6 commands except QUIT, MONITOR, SLOWLOG and SYNC.
  • Pub/sub.
  • Transactions.
  • Pipelining.
  • Connection pool.
  • TLS connections.
  • Thread safety.

Installation

Install:

go get github.com/vmihailenco/redis

Getting started

Let's start with connecting to Redis:

password := "" // no password set
db := -1 // use default DB
client := redis.NewTCPClient("localhost:6379", password, db)
defer client.Close()

Then we can start sending commands:

if err := client.Set("foo", "bar"); err != nil { panic(err) }

get := client.Get("foo")
if err := get.Err(); err != nil { panic(err) }
fmt.Println(get.Val())

We can also pipeline two commands together:

var set *redis.StatusReq
var get *redis.StringReq
reqs, err := client.Pipelined(func(c *redis.PipelineClient)) {
    set = c.Set("key1", "hello1")
    get = c.Get("key2")
}
if err != nil { panic(err) }
if err := set.Err(); err != nil { panic(err) }
if err := get.Err(); err != nil { panic(err) }
fmt.Println(get.Val())
fmt.Println(reqs[0] == set)
fmt.Println(reqs[1] == get)

or:

pipeline, err := client.PipelineClient()
if err != nil {
    panic(err)
}
defer pipeline.Close()

set := pipeline.Set("key1", "hello1")
get := pipline.Get("key2")

reqs, err := pipeline.RunQueued()
if err != nil { panic(err) }

if err := set.Err(); err != nil { panic(err) }
if err := get.Err(); err != nil { panic(err) }
fmt.Println(get.Val())
fmt.Println(reqs[0] == set)
fmt.Println(reqs[1] == get)

We can also send several commands in transaction:

func incrKeyInTransaction(multi *redis.MultiClient) ([]redis.Req, error) {
    get := multi.Get("key")
    if err := get.Err(); err != nil {
        panic(err)
    }

    val, err := strconv.ParseInt(get.Val(), 10, 64)
    if err != nil { panic(err) }

    reqs, err = multi.Exec(func() {
        multi.Set("key", val + 1)
    })
    // Transaction failed. Repeat.
    if err == redis.Nil {
        return incrKeyInTransaction(multi)
    }
    return reqs, err
}

multi, err := client.MultiClient()
if err != nil { panic(err) }
defer multi.Close()

watch := multi.Watch("key")
if err := watch.Err(); err != nil { panic(err) }

reqs, err := incrKeyInTransaction(multi)
if err != nil { panic(err) }
for _, req := range reqs {
    // ...
}

To subscribe to the channel:

pubsub, err := client.PubSubClient()
if err != nil { panic(err) }
defer pubsub.Close()

ch, err := pubsub.Subscribe("mychannel")
if err != nil { panic(err) }

go func() {
    for msg := range ch {
        if err := msg.Err; err != nil { panic(err) }
        message := msg.Message
    }
}

You can also write custom commands:

func Get(client *redis.Client, key string) *redis.StringReq {
    req := redis.NewStringReq("GET", key)
    client.Process(req)
    return req
}

get := Get(redisClient, "key")
if err := get.Err(); err != nil && err != redis.Nil { panic(err) }

Client uses connection pool to send commands. You can change maximum number of connections with:

client.ConnPool.(*redis.MultiConnPool).MaxCap = 1

Look and feel

Some corner cases:

SORT list LIMIT 0 2 ASC
client.Sort("list", redis.Sort{Offset: 0, Count: 2, Order: "ASC"})

ZRANGEBYSCORE zset -inf +inf WITHSCORES LIMIT 0 2
client.ZRangeByScoreWithScores("zset", "-inf", "+inf", 0, 2)

ZINTERSTORE out 2 zset1 zset2 WEIGHTS 2 3 AGGREGATE SUM
client.ZInterStore("out", redis.ZStore{Weights: []int64{2, 3}}, "zset1", "zset2")

EVAL "return {KEYS[1],ARGV[1]}" 1 "key" "hello"
client.Eval("return {KEYS[1],ARGV[1]}", []string{"key"}, []string{"hello"})

Contributing

Configure Redis to allow maximum 10 clients:

maxclients 10

Run tests:

go test -gocheck.v

Run benchmarks:

go test -gocheck.b