redis-mget-example-v1.go

package main

import (
	"encoding/json"
	"errors"
	"fmt"
	"github.com/go-redis/redis"
	"log"
	"reflect"
)

type redisItemCallback func(key string, value interface{}) error

func MGet(redisClient *redis.Client, IDs interface{}, itemCallback redisItemCallback) error {
	rv := reflect.ValueOf(IDs)
	if rv.Len() == 0 {
		return nil
	}
	redisKeys := make([]string, 0, rv.Len())
	for i := 0; i < rv.Len(); i++ {
		redisKeys = append(redisKeys, fmt.Sprint(rv.Index(i)))
	}
	values, err := redisClient.MGet(redisKeys...).Result()
	if err != nil {
		return err
	}
	for i, v := range values {
		if err := itemCallback(redisKeys[i], v); err != nil {
			return err
		}
	}
	return nil
}

func main() {
	client := redis.NewClient(&redis.Options{
		Addr:     "localhost:6379",
		Password: "", // no password set
		DB:       0,  // use default DB
	})
	if err := client.Ping().Err(); err != nil {
		log.Fatal(err)
	}

	type myType struct {
		ID   int
		Info string
	}

	myMap := make(map[int]myType)
	err := MGet(client, []int{1, 2}, func(key string, v interface{}) error {
		strVal, ok := v.(string)
		if !ok {
			return errors.New("invalid redis response type")
		}
		var myTypeVal myType
		if err := json.Unmarshal([]byte(strVal), &myTypeVal); err != nil {
			return fmt.Errorf("unexpected redis value format for key: %s", key)
		}
		myMap[myTypeVal.ID] = myTypeVal
		return nil
	})

	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(myMap)
}