如何實現(xiàn)springboot+aop+Lua分布式限流

// 限流的個數(shù)
  private int maxCount = 10;
  // 指定的時間內(nèi)
  private long interval = 60;
  // 原子類計數(shù)器
  private AtomicInteger atomicInteger = new AtomicInteger(0);
  // 起始時間
  private long startTime = System.currentTimeMillis();

  public boolean limit(int maxCount, int interval) {
    atomicInteger.addAndGet(1);
    if (atomicInteger.get() == 1) {
      startTime = System.currentTimeMillis();
      atomicInteger.addAndGet(1);
      return true;
    }
    // 超過了間隔時間，直接重新開始計數(shù)
    if (System.currentTimeMillis() - startTime > interval * 1000) {
      startTime = System.currentTimeMillis();
      atomicInteger.set(1);
      return true;
    }
    // 還在間隔時間內(nèi),check有沒有超過限流的個數(shù)
    if (atomicInteger.get() > maxCount) {
      return false;
    }
    return true;
  }

-- 獲取調(diào)用腳本時傳入的第一個key值（用作限流的 key）
local key = KEYS[1]
-- 獲取調(diào)用腳本時傳入的第一個參數(shù)值（限流大?。?
local limit = tonumber(ARGV[1])

-- 獲取當(dāng)前流量大小
local curentLimit = tonumber(redis.call('get', key) or "0")

-- 是否超出限流
if curentLimit + 1 > limit then
  -- 返回(拒絕)
  return 0
else
  -- 沒有超出 value + 1
  redis.call("INCRBY", key, 1)
  -- 設(shè)置過期時間
  redis.call("EXPIRE", key, 2)
  -- 返回(放行)
  return 1
end

<dependencies>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-data-redis</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-aop</artifactId>
    </dependency>
    <dependency>
      <groupId>com.google.guava</groupId>
      <artifactId>guava</artifactId>
      <version>21.0</version>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-test</artifactId>
    </dependency>
    <dependency>
      <groupId>org.apache.commons</groupId>
      <artifactId>commons-lang3</artifactId>
    </dependency>

    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-test</artifactId>
      <scope>test</scope>
      <exclusions>
        <exclusion>
          <groupId>org.junit.vintage</groupId>
          <artifactId>junit-vintage-engine</artifactId>
        </exclusion>
      </exclusions>
    </dependency>
  </dependencies>

spring.redis.host=127.0.0.1
spring.redis.port=6379

@Configuration
public class RedisLimiterHelper {

  @Bean
  public RedisTemplate<String, Serializable> limitRedisTemplate(LettuceConnectionFactory redisConnectionFactory) {
    RedisTemplate<String, Serializable> template = new RedisTemplate<>();
    template.setKeySerializer(new StringRedisSerializer());
    template.setValueSerializer(new GenericJackson2JsonRedisSerializer());
    template.setConnectionFactory(redisConnectionFactory);
    return template;
  }
}

/**
 * @author fu
 * @description 限流類型
 * @date 2020/4/8 13:47
 */
public enum LimitType {

  /**
   * 自定義key
   */
  CUSTOMER,

  /**
   * 請求者IP
   */
  IP;
}

/**
 * @author fu
 * @description 自定義限流注解
 * @date 2020/4/8 13:15
 */
@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Inherited
@Documented
public @interface Limit {

  /**
   * 名字
   */
  String name() default "";

  /**
   * key
   */
  String key() default "";

  /**
   * Key的前綴
   */
  String prefix() default "";

  /**
   * 給定的時間范圍 單位(秒)
   */
  int period();

  /**
   * 一定時間內(nèi)最多訪問次數(shù)
   */
  int count();

  /**
   * 限流的類型(用戶自定義key 或者 請求ip)
   */
  LimitType limitType() default LimitType.CUSTOMER;
}

/**
 * @author fu
 * @description 限流切面實現(xiàn)
 * @date 2020/4/8 13:04
 */
@Aspect
@Configuration
public class LimitInterceptor {

  private static final Logger logger = LoggerFactory.getLogger(LimitInterceptor.class);

  private static final String UNKNOWN = "unknown";

  private final RedisTemplate<String, Serializable> limitRedisTemplate;

  @Autowired
  public LimitInterceptor(RedisTemplate<String, Serializable> limitRedisTemplate) {
    this.limitRedisTemplate = limitRedisTemplate;
  }

  /**
   * @param pjp
   * @author fu
   * @description 切面
   * @date 2020/4/8 13:04
   */
  @Around("execution(public * *(..)) && @annotation(com.xiaofu.limit.api.Limit)")
  public Object interceptor(ProceedingJoinPoint pjp) {
    MethodSignature signature = (MethodSignature) pjp.getSignature();
    Method method = signature.getMethod();
    Limit limitAnnotation = method.getAnnotation(Limit.class);
    LimitType limitType = limitAnnotation.limitType();
    String name = limitAnnotation.name();
    String key;
    int limitPeriod = limitAnnotation.period();
    int limitCount = limitAnnotation.count();

    /**
     * 根據(jù)限流類型獲取不同的key ,如果不傳我們會以方法名作為key
     */
    switch (limitType) {
      case IP:
        key = getIpAddress();
        break;
      case CUSTOMER:
        key = limitAnnotation.key();
        break;
      default:
        key = StringUtils.upperCase(method.getName());
    }

    ImmutableList<String> keys = ImmutableList.of(StringUtils.join(limitAnnotation.prefix(), key));
    try {
      String luaScript = buildLuaScript();
      RedisScript<Number> redisScript = new DefaultRedisScript<>(luaScript, Number.class);
      Number count = limitRedisTemplate.execute(redisScript, keys, limitCount, limitPeriod);
      logger.info("Access try count is {} for name={} and key = {}", count, name, key);
      if (count != null && count.intValue() <= limitCount) {
        return pjp.proceed();
      } else {
        throw new RuntimeException("You have been dragged into the blacklist");
      }
    } catch (Throwable e) {
      if (e instanceof RuntimeException) {
        throw new RuntimeException(e.getLocalizedMessage());
      }
      throw new RuntimeException("server exception");
    }
  }

  /**
   * @author fu
   * @description 編寫 redis Lua 限流腳本
   * @date 2020/4/8 13:24
   */
  public String buildLuaScript() {
    StringBuilder lua = new StringBuilder();
    lua.append("local c");
    lua.append("\nc = redis.call('get',KEYS[1])");
    // 調(diào)用不超過最大值，則直接返回
    lua.append("\nif c and tonumber(c) > tonumber(ARGV[1]) then");
    lua.append("\nreturn c;");
    lua.append("\nend");
    // 執(zhí)行計算器自加
    lua.append("\nc = redis.call('incr',KEYS[1])");
    lua.append("\nif tonumber(c) == 1 then");
    // 從第一次調(diào)用開始限流，設(shè)置對應(yīng)鍵值的過期
    lua.append("\nredis.call('expire',KEYS[1],ARGV[2])");
    lua.append("\nend");
    lua.append("\nreturn c;");
    return lua.toString();
  }


  /**
   * @author fu
   * @description 獲取id地址
   * @date 2020/4/8 13:24
   */
  public String getIpAddress() {
    HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
    String ip = request.getHeader("x-forwarded-for");
    if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
      ip = request.getHeader("Proxy-Client-IP");
    }
    if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
      ip = request.getHeader("WL-Proxy-Client-IP");
    }
    if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
      ip = request.getRemoteAddr();
    }
    return ip;
  }
}

/**
 * @Author: fu
 * @Description:
 */
@RestController
public class LimiterController {

  private static final AtomicInteger ATOMIC_INTEGER_1 = new AtomicInteger();
  private static final AtomicInteger ATOMIC_INTEGER_2 = new AtomicInteger();
  private static final AtomicInteger ATOMIC_INTEGER_3 = new AtomicInteger();

  /**
   * @author fu
   * @description
   * @date 2020/4/8 13:42
   */
  @Limit(key = "limitTest", period = 10, count = 3)
  @GetMapping("/limitTest1")
  public int testLimiter1() {

    return ATOMIC_INTEGER_1.incrementAndGet();
  }

  /**
   * @author fu
   * @description
   * @date 2020/4/8 13:42
   */
  @Limit(key = "customer_limit_test", period = 10, count = 3, limitType = LimitType.CUSTOMER)
  @GetMapping("/limitTest2")
  public int testLimiter2() {

    return ATOMIC_INTEGER_2.incrementAndGet();
  }

  /**
   * @author fu
   * @description 
   * @date 2020/4/8 13:42
   */
  @Limit(key = "ip_limit_test", period = 10, count = 3, limitType = LimitType.IP)
  @GetMapping("/limitTest3")
  public int testLimiter3() {

    return ATOMIC_INTEGER_3.incrementAndGet();
  }

}