redis/v2/example_test.go

package redis_test

import (
	"fmt"
	"strconv"

	"github.com/vmihailenco/redis/v2"
)

var client *redis.Client

func init() {
	client = redis.NewTCPClient(&redis.Options{
		Addr: ":6379",
	})
}

func ExampleNewTCPClient() {
	client := redis.NewTCPClient(&redis.Options{
		Addr:     "localhost:6379",
		Password: "", // no password set
		DB:       0,  // use default DB
	})
	defer client.Close()

	ping := client.Ping()
	fmt.Println(ping.Val(), ping.Err())
	// Output: PONG <nil>
}

func ExampleClient() {
	set := client.Set("foo", "bar")
	fmt.Println(set.Val(), set.Err())

	get := client.Get("hello")
	fmt.Printf("%q %s %v", get.Val(), get.Err(), get.Err() == redis.Nil)

	// Output: OK <nil>
	// "" redis: nil true
}

func ExampleClient_Pipelined() {
	cmds, err := client.Pipelined(func(c *redis.Pipeline) {
		c.Set("key1", "hello1")
		c.Get("key1")
	})
	set := cmds[0].(*redis.StatusCmd)
	get := cmds[1].(*redis.StringCmd)
	fmt.Println(set, get, err)
	// Output: SET key1 hello1: OK GET key1: hello1 <nil>
}

func ExamplePipeline() {
	pipeline := client.Pipeline()
	set := pipeline.Set("key1", "hello1")
	get := pipeline.Get("key1")
	cmds, err := pipeline.Exec()
	fmt.Println(cmds, err)
	fmt.Println(set)
	fmt.Println(get)
	// Output: [SET key1 hello1: OK GET key1: hello1] <nil>
	// SET key1 hello1: OK
	// GET key1: hello1
}

func ExampleMulti() {
	incr := func(tx *redis.Multi) ([]redis.Cmder, error) {
		get := tx.Get("key")
		if err := get.Err(); err != nil && err != redis.Nil {
			return nil, err
		}

		val, _ := strconv.ParseInt(get.Val(), 10, 64)

		return tx.Exec(func() {
			tx.Set("key", strconv.FormatInt(val+1, 10))
		})
	}

	client.Del("key")

	tx := client.Multi()
	defer tx.Close()

	watch := tx.Watch("key")
	_ = watch.Err()

	for {
		cmds, err := incr(tx)
		if err == redis.TxFailedErr {
			continue
		} else if err != nil {
			panic(err)
		}
		fmt.Println(cmds, err)
		break
	}

	// Output: [SET key 1: OK] <nil>
}

func ExamplePubSub() {
	pubsub := client.PubSub()
	defer pubsub.Close()

	err := pubsub.Subscribe("mychannel")
	_ = err

	msg, err := pubsub.Receive()
	fmt.Println(msg, err)

	pub := client.Publish("mychannel", "hello")
	_ = pub.Err()

	msg, err = pubsub.Receive()
	fmt.Println(msg, err)

	// Output: &{subscribe mychannel 1} <nil>
	// &{mychannel hello} <nil>
}

func ExampleScript() {
	setnx := redis.NewScript(`
        if redis.call("get", KEYS[1]) == false then
            redis.call("set", KEYS[1], ARGV[1])
            return 1
        end
        return 0
    `)

	run1 := setnx.Run(client, []string{"keynx"}, []string{"foo"})
	fmt.Println(run1.Val().(int64), run1.Err())

	run2 := setnx.Run(client, []string{"keynx"}, []string{"bar"})
	fmt.Println(run2.Val().(int64), run2.Err())

	get := client.Get("keynx")
	fmt.Println(get)

	// Output: 1 <nil>
	// 0 <nil>
	// GET keynx: foo
}

func Example_customCommand() {
	Get := func(client *redis.Client, key string) *redis.StringCmd {
		cmd := redis.NewStringCmd("GET", key)
		client.Process(cmd)
		return cmd
	}

	get := Get(client, "key_does_not_exist")
	fmt.Printf("%q %s", get.Val(), get.Err())
	// Output: "" redis: nil
}