redis_lock.go 自旋锁

package main

import (
	"fmt"
	"github.com/go-redis/redis"
	"sync"
	"time"
)

func acquireLock(client *redis.Client, key string, value string, expiration time.Duration) (bool, error) {
	for {
		result, err := client.SetNX(key, value, expiration).Result()
		fmt.Println(result)
		if err != nil {
			return false, err
		}
		if result {
			return true, nil
		}
		time.Sleep(100 * time.Millisecond) // 自旋等待时间
	}
}

func releaseLock(client *redis.Client, key string, value string) error {
	script := redis.NewScript(`
		if redis.call("get", KEYS[1]) == ARGV[1] then
			return redis.call("del", KEYS[1])
		else
			return 0
		end
	`)
	_, err := script.Run(client, []string{key}, value).Result()
	return err
}

func main() {
	var wg sync.WaitGroup
	wg.Add(10)

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

	for i := 0; i < 100; i++ {
		defer wg.Done()

		key := "mylock"
		value := "unique_value_for_this_lock"
		expiration := 5 * time.Second

		locked, err := acquireLock(client, key, value, expiration)
		if err != nil {
			fmt.Println("Failed to acquire lock:", err)
			return
		}
		if !locked {
			fmt.Println("Failed to acquire lock")
			return
		}
		defer func() {
			err := releaseLock(client, key, value)
			if err != nil {
				fmt.Println("Failed to release lock:", err)
			}
		}()

		// 在这里执行需要加锁的操作
		fmt.Println("Lock acquired, performing operation...", time.Now().String())
		time.Sleep(2 * time.Second)
		fmt.Println("Operation completed.", time.Now().String())
	}

	wg.Wait()
}