Requirement

For Redis: go-redis client version >= v6.15

For RocketMQ: rocketmq-client-go version >= v2

Installation

go get github.com/volcengine/dns-stale-cache

Example

For rocketmq client/v2

package main

import (
    "context"
    "fmt"
    "os"
    "strconv"

    "github.com/apache/rocketmq-client-go/v2"
    "github.com/apache/rocketmq-client-go/v2/primitive"
    "github.com/apache/rocketmq-client-go/v2/producer"
    . "github.com/volcengine/dns-stale-cache/common"
    . "github.com/volcengine/dns-stale-cache/rocketmq/v2"
)

// Package main implements a simple producer to send message.
func main() {
    addrs := []string{"localhost:9876"}
    
    p, _ := rocketmq.NewProducer(
        producer.WithNsResolver(NewCacheResolver(addrs,
            WithCacheFirst(true),
            WithIPConsistance(true),
            WithDnsTimeout(1*time.Second),
        )),
        producer.WithRetry(2),
    )
    err := p.Start()
    if err != nil {
        fmt.Printf("start producer error: %s", err.Error())
        os.Exit(1)
    }
    topic := "TopicTest"

    for i := 0; i < 10; i++ {
        msg := &primitive.Message{
            Topic: topic,
            Body:  []byte("Hello RocketMQ Go Client! " + strconv.Itoa(i)),
        }
        res, err := p.SendSync(context.Background(), msg)

        if err != nil {
            fmt.Printf("send message error: %s\n", err)
        } else {
            fmt.Printf("send message success: result=%s\n", res.String())
        }
    }
    err = p.Shutdown()
    if err != nil {
        fmt.Printf("shutdown producer error: %s", err.Error())
    }
}

For redis client/v9

package main

import (
    "context"
    "errors"
    "fmt"
    "time"

    "github.com/redis/go-redis/v9"
    . "github.com/volcengine/dns-stale-cache/common"
    . "github.com/volcengine/dns-stale-cache/redis/v9"
)

func ExampleNewClient() {
    opt := &redis.Options{
        Addr:     "localhost:6379", // use default Addr
    }

    opt.Dialer = NewDialerWithCache(opt,
        WithCacheFirst(true),
        WithIPConsistance(true),
        WithDnsTimeout(2*time.Second),
    )
    rdb := redis.NewClient(opt)

    pong, err := rdb.Ping(context.Background()).Result()
    fmt.Println(pong, err)
    // Output: PONG <nil>
}