java - lua - cas

使用lua 实现cas操作

@Bean(name = "customStringRedisTemplate")
public RedisTemplate<String, String> customStringRedisTemplate(RedisConnectionFactory factory) {
    return new StringRedisTemplate(factory);
}

@Autowired
private RedisTemplate<String, String> customStringRedisTemplate;

String luaCustomCas = "if redis.call('exists',KEYS[1]) == 1 then \n" +
        "   if redis.call('get', KEYS[1]) < ARGV[1] then\n" +
        "       redis.call('set', KEYS[1], ARGV[1])\n" +
        "       redis.call('expire', KEYS[1], ARGV[2])\n" +
        "       return 1\n" +
        "   else\n" +
        "       return 0\n" +
        "   end\n" +
        "else\n" +
        "   redis.call('set',KEYS[1], ARGV[1])\n" +
        "   redis.call('expire', KEYS[1], ARGV[2])\n" +
        "   return 1\n" +
        "   end\n";
String key = "customKey";
customStringRedisTemplate.delete(key);
// 指定 lua 脚本，并且指定返回值类型
DefaultRedisScript<Long> redisScript = new DefaultRedisScript<>(luaCustomCas, Long.class);
for (int i = 0; i < 2; i++) {
    // 参数一：redisScript，参数二：key列表，参数三：arg（可多个）
    Long result = customStringRedisTemplate.execute(redisScript, Collections.singletonList(key), "1", "100");
    log.info("{}", result);
}
customStringRedisTemplate.delete(key);