Api接口需要实现限流,例如每分钟可以请求60次,超过频率则提示:接口请求频繁。业务本身使用了redisson作为Redis的客户端,所以采用官方提供的RRateLimiter来实现接口限流。
1. maven依赖引入
<dependency>
<groupId>org.redisson</groupId>
<artifactId>redisson</artifactId>
<version>3.17.3</version>
</dependency>
2. redis配置
spring:
redisson:
database: 1
address: redis://127.0.0.1:6379
password:
connectionPoolSize: 8
connectionMinimumIdleSize: 3
subscriptionConnectionPoolSize: 6
subscriptionConnectionMinimumIdleSize: 1
Redis的客户端接入代码如下:
@Configuration
public class RedisSingleConfig {
@Value("${spring.redis.host}")
private String host;
@Value("${spring.redis.port}")
private String port;
@Value("${spring.redis.password}")
private String password;
@Value("${spring.redis.database}")
private int dataBase;
@Bean
public RedissonClient redissonClient() {
Config config = new Config();
String redisUrl = String.format("redis://%s:%s", host + "", port + "");
config.useSingleServer().setTimeout(1000)
.setRetryAttempts(3)
.setRetryInterval(1500) //ms
.setAddress(redisUrl);
if (StringUtils.isNotBlank(password)) {
config.useSingleServer().setPassword(password);
}
SingleServerConfig singleConfig = config.useSingleServer()
.setAddress(redisUrl)
.setPingConnectionInterval(1000);//心跳检测,定时与redis连接,可以防止一段时间过后,与redis的连接断开
singleConfig.setPassword(password);
config.useSingleServer().setDatabase(dataBase);
return Redisson.create(config);
}
}
3. redisson客户单配置
@Component
public class RedissonClientConfig {
@Value("${spring.redisson.address}")
private String address;
@Value("${spring.redisson.database}")
private Integer dataBase;
@Bean
public RedissonClient redissonClient(){
Config config = new Config();
config.useSingleServer().setAddress(address)
.setDatabase(dataBase);
return Redisson.create(config);
}
}
4. 自定义限流注解
@Target({ElementType.TYPE, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface ApiRateLimiter {
String name();
long rate() default 180;
long rateInterval() default 60;
}
5. 定义简单的工厂模式
public class RateLimiterFactory {
private volatile static RateLimiterFactory SINGLETON;
private RateLimiterFactory() {
}
private final ConcurrentHashMap<String, RRateLimiter> rateLimiterMap = new ConcurrentHashMap<>();
public static RateLimiterFactory getSingleton() {
if (null == SINGLETON) {
synchronized (RateLimiterFactory.class) {
if (null == SINGLETON) {
SINGLETON = new RateLimiterFactory();
}
}
}
return SINGLETON;
}
public RRateLimiter get(String name, long rate,long rateInterval) {
if (StringUtils.isBlank(name)) {
throw new IllegalArgumentException("rate name can not be empty");
}
if (rate < 0) {
throw new IllegalArgumentException("rate must be >0");
}
RRateLimiter rRateLimiter = rateLimiterMap.get(name);
if (null == rRateLimiter) {
RedissonClient redissonClient = (RedissonClient) SpringContextUtil.getBean("redissonClient");
rRateLimiter = redissonClient.getRateLimiter(name);
//根据业务选择 RateType 参数
rRateLimiter.setRate(RateType.OVERALL, rate, rateInterval, RateIntervalUnit.SECONDS);
rateLimiterMap.put(name, rRateLimiter);
}
return rRateLimiter;
}
}
6. 定义切面
@Slf4j
@Component
@Aspect
public class ApiRateLimitAspect {
@Pointcut("@annotation(ApiRateLimiter类路径)")
public void rateLimitPoint() {
}
@Around("rateLimitPoint()")
public Object aroundAop(ProceedingJoinPoint joinPoint) throws Throwable {
Method method = ((MethodSignature) joinPoint.getSignature()).getMethod();
ApiRateLimiter apiRateLimiter = AnnotationUtils.getAnnotation(method, ApiRateLimiter.class);
if (null == apiRateLimiter) {
return joinPoint.proceed();
}
long rate = apiRateLimiter.rate();
long rateInterval = apiRateLimiter.rateInterval();
String name = apiRateLimiter.name();
RRateLimiter newRankLimiter = RateLimiterFactory.getSingleton().get(name, rate,rateInterval );
//根据业务选择 acquire 以及 tryAcquire
newRankLimiter.acquire();
return joinPoint.proceed();
}
7. 编写接口进行限流测试
@ApiRateLimiter(name = "ratelimitApi", rate = 5, rateInterval = 60)
@RequestMapping(value = "/rate/limit", method = RequestMethod.POST)
public RspInfoBO rateLimit(ApplyTrialReqBO reqInfoBO) {
RspInfoBO res = new RspInfoBO();
return res;
}
如果使用的是阿里云的Redis套件,需要设置阿里云Redis参数 script_check_enable参数为0