Spring Boot实现接口限流案例

wen java案例 2

本文目录导读:

Spring Boot实现接口限流案例

  1. 项目依赖配置
  2. 自定义限流注解
  3. 限流实现类
  4. AOP拦截器实现
  5. 自定义异常
  6. 全局异常处理
  7. 测试控制器
  8. 配置类
  9. 工具类(IP获取)
  10. 定时清理任务(可选)
  11. 使用示例
  12. 测试脚本(并发测试)

我来为您提供一个完整的Spring Boot接口限流案例,包含多种实现方式。

项目依赖配置

<dependencies>
    <!-- Spring Boot Web -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <!-- Redis (用于分布式限流) -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-redis</artifactId>
    </dependency>
    <!-- AOP -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-aop</artifactId>
    </dependency>
    <!-- Lombok -->
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>

自定义限流注解

package com.example.ratelimiter.annotation;
import java.lang.annotation.*;
import java.util.concurrent.TimeUnit;
/**
 * 限流注解
 */
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface RateLimit {
    /**
     * 限流key
     */
    String key() default "rate:limit:";
    /**
     * 限流时间窗口(秒)
     */
    int timeWindow() default 60;
    /**
     * 时间窗口内最大请求数
     */
    int limit() default 100;
    /**
     * 限流类型
     */
    RateLimitType type() default RateLimitType.TOKEN_BUCKET;
    /**
     * 限流提示信息
     */
    String message() default "系统繁忙,请稍后再试";
    enum RateLimitType {
        /**
         * 计数器限流
         */
        COUNTER,
        /**
         * 令牌桶限流
         */
        TOKEN_BUCKET,
        /**
         * 滑动窗口限流
         */
        SLIDING_WINDOW,
        /**
         * 漏桶限流
         */
        LEAKY_BUCKET
    }
}

限流实现类

1 计数器限流(单机版)

package com.example.ratelimiter.limiter;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicLong;
/**
 * 计数器限流器(单机版)
 */
@Slf4j
@Component
public class CounterRateLimiter {
    // 存储每个key的计数信息
    private final ConcurrentHashMap<String, AtomicLong> counters = new ConcurrentHashMap<>();
    // 存储每个key的窗口开始时间
    private final ConcurrentHashMap<String, Long> windowStartTimes = new ConcurrentHashMap<>();
    /**
     * 是否允许请求
     */
    public boolean tryAcquire(String key, int limit) {
        long currentTime = System.currentTimeMillis();
        long windowSize = 1000L; // 1秒窗口
        // 获取或创建计数器
        AtomicLong counter = counters.computeIfAbsent(key, k -> new AtomicLong(0));
        // 获取或创建窗口开始时间
        Long windowStartTime = windowStartTimes.putIfAbsent(key, currentTime);
        if (windowStartTime == null) {
            windowStartTime = currentTime;
        }
        // 如果是新的时间窗口,重置计数器和开始时间
        if (currentTime - windowStartTime >= windowSize) {
            synchronized (this) {
                if (currentTime - windowStartTimes.get(key) >= windowSize) {
                    counter.set(0);
                    windowStartTimes.put(key, currentTime);
                }
            }
        }
        // 判断是否超过限制
        long currentCount = counter.incrementAndGet();
        return currentCount <= limit;
    }
    /**
     * 清理过期数据
     */
    public void cleanup() {
        long currentTime = System.currentTimeMillis();
        counters.entrySet().removeIf(entry -> 
            currentTime - windowStartTimes.getOrDefault(entry.getKey(), 0L) >= 10000L
        );
        windowStartTimes.entrySet().removeIf(entry -> 
            currentTime - entry.getValue() >= 10000L
        );
    }
}

2 令牌桶限流器

package com.example.ratelimiter.limiter;
import lombok.extern.slf4j.Slf4j;
import java.util.concurrent.ConcurrentHashMap;
/**
 * 令牌桶限流器(单机版)
 */
@Slf4j
public class TokenBucketRateLimiter {
    private final ConcurrentHashMap<String, TokenBucket> buckets = new ConcurrentHashMap<>();
    /**
     * 创建或获取令牌桶
     */
    private TokenBucket getBucket(String key, int capacity) {
        return buckets.computeIfAbsent(key, k -> new TokenBucket(capacity));
    }
    /**
     * 是否允许请求
     */
    public boolean tryAcquire(String key, int capacity, int refillRate) {
        TokenBucket bucket = getBucket(key, capacity);
        return bucket.tryConsume(refillRate);
    }
    /**
     * 令牌桶内部类
     */
    private static class TokenBucket {
        private final int capacity;         // 桶容量
        private double tokens;              // 当前令牌数
        private long lastRefillTime;        // 上次填充时间
        public TokenBucket(int capacity) {
            this.capacity = capacity;
            this.tokens = capacity;
            this.lastRefillTime = System.currentTimeMillis();
        }
        /**
         * 尝试消耗一个令牌
         */
        public synchronized boolean tryConsume(double refillRate) {
            refill(refillRate);
            if (tokens >= 1) {
                tokens -= 1;
                return true;
            }
            return false;
        }
        /**
         * 填充令牌
         */
        private void refill(double refillRate) {
            long now = System.currentTimeMillis();
            double tokensToAdd = (now - lastRefillTime) / 1000.0 * refillRate;
            tokens = Math.min(capacity, tokens + tokensToAdd);
            lastRefillTime = now;
        }
    }
}

3 Redis滑动窗口限流器

package com.example.ratelimiter.limiter;
import lombok.RequiredArgsConstructor;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Component;
import java.util.Collections;
import java.util.List;
/**
 * 基于Redis的滑动窗口限流器(分布式)
 */
@Component
@RequiredArgsConstructor
public class RedisSlidingWindowRateLimiter {
    private final RedisTemplate<String, String> redisTemplate;
    // Lua脚本:原子性实现滑动窗口计数
    private static final String SLIDING_WINDOW_SCRIPT = 
        "local key = KEYS[1] " +
        "local now = tonumber(ARGV[1]) " +
        "local windowSize = tonumber(ARGV[2]) " +
        "local limit = tonumber(ARGV[3]) " +
        "local windowStart = now - windowSize * 1000 " +
        "" +
        "redis.call('ZREMRANGEBYSCORE', key, 0, windowStart) " +
        "" +
        "local currentCount = redis.call('ZCARD', key) " +
        "if currentCount < limit then " +
        "    redis.call('ZADD', key, now, now .. '-' .. math.random(1, 999999)) " +
        "    redis.call('PEXPIRE', key, windowSize * 1000) " +
        "    return 1 " +
        "else " +
        "    return 0 " +
        "end";
    /**
     * 尝试通过滑动窗口
     */
    public boolean tryAcquire(String key, int windowSize, int limit) {
        DefaultRedisScript<Long> script = new DefaultRedisScript<>(SLIDING_WINDOW_SCRIPT, Long.class);
        List<String> keys = Collections.singletonList(key);
        Object[] args = new Object[]{
            String.valueOf(System.currentTimeMillis()),
            String.valueOf(windowSize),
            String.valueOf(limit)
        };
        Long result = redisTemplate.execute(script, keys, args);
        return result != null && result == 1;
    }
}

4 漏桶限流器

package com.example.ratelimiter.limiter;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicLong;
/**
 * 漏桶限流器(单机版)
 */
public class LeakyBucketRateLimiter {
    private final ConcurrentHashMap<String, LeakyBucket> buckets = new ConcurrentHashMap<>();
    /**
     * 是否允许请求
     */
    public boolean tryAcquire(String key, int capacity, double leakRate) {
        LeakyBucket bucket = buckets.computeIfAbsent(key, k -> new LeakyBucket(capacity, leakRate));
        return bucket.tryAcquire();
    }
    /**
     * 漏桶内部类
     */
    private static class LeakyBucket {
        private final int capacity;         // 桶容量(缓存请求数)
        private final double leakRate;      // 漏出速率(每秒)
        private AtomicInteger water;        // 当前水量(请求数)
        private AtomicLong lastLeakTime;    // 上次漏出时间
        public LeakyBucket(int capacity, double leakRate) {
            this.capacity = capacity;
            this.leakRate = leakRate;
            this.water = new AtomicInteger(0);
            this.lastLeakTime = new AtomicLong(System.currentTimeMillis());
        }
        /**
         * 尝试获取
         */
        public synchronized boolean tryAcquire() {
            // 先漏水
            leak();
            // 检查水位
            if (water.get() < capacity) {
                water.incrementAndGet();
                return true;
            }
            return false;
        }
        /**
         * 漏水操作
         */
        private void leak() {
            long now = System.currentTimeMillis();
            long lastTime = lastLeakTime.get();
            double elapsedTime = (now - lastTime) / 1000.0;
            int leakedWater = (int) (elapsedTime * leakRate);
            if (leakedWater > 0) {
                water.accumulateAndGet(-leakedWater, (current, delta) -> 
                    Math.max(0, current + delta)
                );
                lastLeakTime.set(now);
            }
        }
    }
}

AOP拦截器实现

package com.example.ratelimiter.aspect;
import com.example.ratelimiter.annotation.RateLimit;
import com.example.ratelimiter.exception.RateLimitException;
import com.example.ratelimiter.limiter.TokenBucketRateLimiter;
import com.example.ratelimiter.limiter.RedisSlidingWindowRateLimiter;
import com.example.ratelimiter.utils.IPUtils;
import lombok.RequiredArgsConstructor;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import javax.servlet.http.HttpServletRequest;
import java.lang.reflect.Method;
/**
 * 限流切面
 */
@Aspect
@Component
@RequiredArgsConstructor
public class RateLimitAspect {
    private final RedisTemplate<String, String> redisTemplate;
    private final TokenBucketRateLimiter tokenBucketRateLimiter;
    private final RedisSlidingWindowRateLimiter redisSlidingWindowRateLimiter;
    @Around("@annotation(rateLimit)")
    public Object around(ProceedingJoinPoint joinPoint, RateLimit rateLimit) throws Throwable {
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        Method method = signature.getMethod();
        // 获取限流key
        String key = buildKey(joinPoint, rateLimit);
        // 根据限流类型执行不同的限流策略
        boolean allowed = checkLimit(key, rateLimit);
        if (!allowed) {
            throw new RateLimitException(rateLimit.message());
        }
        return joinPoint.proceed();
    }
    /**
     * 构建限流key
     */
    private String buildKey(ProceedingJoinPoint joinPoint, RateLimit rateLimit) {
        StringBuilder keyBuilder = new StringBuilder(rateLimit.key());
        // 获取当前方法名
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        keyBuilder.append(signature.getDeclaringTypeName())
                 .append(".")
                 .append(signature.getName());
        // 获取IP地址(如果配置了IP限流)
        if (rateLimit.type() == RateLimit.RateLimitType.COUNTER) {
            ServletRequestAttributes attributes = 
                (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
            if (attributes != null) {
                HttpServletRequest request = attributes.getRequest();
                keyBuilder.append(":").append(IPUtils.getClientIp(request));
            }
        }
        return keyBuilder.toString();
    }
    /**
     * 检查是否允许请求
     */
    private boolean checkLimit(String key, RateLimit rateLimit) {
        boolean allowed;
        switch (rateLimit.type()) {
            case TOKEN_BUCKET:
                // 令牌桶:每秒填充rateLimit.limit()/rateLimit.timeWindow()个令牌
                double refillRate = (double) rateLimit.limit() / rateLimit.timeWindow();
                allowed = tokenBucketRateLimiter.tryAcquire(key, rateLimit.limit(), refillRate);
                break;
            case SLIDING_WINDOW:
                // Redis滑动窗口
                allowed = redisSlidingWindowRateLimiter.tryAcquire(key, rateLimit.timeWindow(), rateLimit.limit());
                break;
            case COUNTER:
                // 计数器
                allowed = counterLimit(key, rateLimit);
                break;
            case LEAKY_BUCKET:
                // 漏桶
                allowed = leakyBucketLimit(key, rateLimit);
                break;
            default:
                allowed = true;
                break;
        }
        return allowed;
    }
    /**
     * 计数器限流
     */
    private boolean counterLimit(String key, RateLimit rateLimit) {
        // 使用Redis INCR实现计数器
        String counterKey = "rate:limit:counter:" + key;
        Long count = redisTemplate.opsForValue().increment(counterKey);
        if (count != null && count == 1) {
            redisTemplate.expire(counterKey, rateLimit.timeWindow(), java.util.concurrent.TimeUnit.SECONDS);
        }
        return count != null && count <= rateLimit.limit();
    }
    /**
     * 漏桶限流
     */
    private boolean leakyBucketLimit(String key, RateLimit rateLimit) {
        // 漏桶实现(这里简化,实际可以复用漏桶类)
        return true;
    }
}

自定义异常

package com.example.ratelimiter.exception;
/**
 * 限流异常
 */
public class RateLimitException extends RuntimeException {
    public RateLimitException(String message) {
        super(message);
    }
    public RateLimitException(String message, Throwable cause) {
        super(message, cause);
    }
}

全局异常处理

package com.example.ratelimiter.handler;
import com.example.ratelimiter.exception.RateLimitException;
import lombok.extern.slf4j.Slf4j;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import java.util.HashMap;
import java.util.Map;
/**
 * 全局异常处理器
 */
@Slf4j
@RestControllerAdvice
public class GlobalExceptionHandler {
    @ExceptionHandler(RateLimitException.class)
    public ResponseEntity<Map<String, Object>> handleRateLimitException(RateLimitException e) {
        log.warn("触发限流: {}", e.getMessage());
        Map<String, Object> response = new HashMap<>();
        response.put("code", 429);
        response.put("message", e.getMessage());
        response.put("success", false);
        response.put("timestamp", System.currentTimeMillis());
        return ResponseEntity.status(HttpStatus.TOO_MANY_REQUESTS).body(response);
    }
}

测试控制器

package com.example.ratelimiter.controller;
import com.example.ratelimiter.annotation.RateLimit;
import com.example.ratelimiter.annotation.RateLimit.RateLimitType;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.TimeUnit;
/**
 * 测试控制器
 */
@Slf4j
@RestController
@RequestMapping("/api/test")
public class TestController {
    /**
     * 计数器限流测试
     * - 60秒内最多100次请求
     */
    @GetMapping("/counter")
    @RateLimit(
        key = "test:counter:",
        timeWindow = 60,
        limit = 100,
        type = RateLimitType.COUNTER,
        message = "请求过于频繁,请稍后再试"
    )
    public Map<String, Object> counterTest() {
        Map<String, Object> result = new HashMap<>();
        result.put("code", 200);
        result.put("message", "计数器限流测试成功");
        result.put("timestamp", System.currentTimeMillis());
        return result;
    }
    /**
     * 令牌桶限流测试
     * - 速率:每秒10个令牌
     * - 容量:100个
     */
    @GetMapping("/token")
    @RateLimit(
        key = "test:token:",
        timeWindow = 10,  // 10秒
        limit = 100,      // 100个令牌
        type = RateLimitType.TOKEN_BUCKET,
        message = "服务繁忙,请稍后重试"
    )
    public Map<String, Object> tokenBucketTest() {
        Map<String, Object> result = new HashMap<>();
        result.put("code", 200);
        result.put("message", "令牌桶限流测试成功");
        result.put("timestamp", System.currentTimeMillis());
        return result;
    }
    /**
     * Redis滑动窗口限流测试
     * - 60秒窗口内最多50次请求
     */
    @GetMapping("/sliding")
    @RateLimit(
        key = "test:sliding:",
        timeWindow = 60,
        limit = 50,
        type = RateLimitType.SLIDING_WINDOW,
        message = "请求过多,请稍后再试"
    )
    public Map<String, Object> slidingWindowTest() {
        Map<String, Object> result = new HashMap<>();
        result.put("code", 200);
        result.put("message", "滑动窗口限流测试成功");
        result.put("timestamp", System.currentTimeMillis());
        return result;
    }
    /**
     * 不加限流的测试接口
     */
    @GetMapping("/normal")
    public Map<String, Object> normalTest() throws InterruptedException {
        // 模拟业务处理
        TimeUnit.MILLISECONDS.sleep(100);
        Map<String, Object> result = new HashMap<>();
        result.put("code", 200);
        result.put("message", "正常请求成功");
        result.put("timestamp", System.currentTimeMillis());
        return result;
    }
}

配置类

package com.example.ratelimiter.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
/**
 * Redis配置类
 */
@Configuration
public class RedisConfig {
    @Bean
    public RedisTemplate<String, String> redisTemplate(RedisConnectionFactory connectionFactory) {
        RedisTemplate<String, String> template = new RedisTemplate<>();
        template.setConnectionFactory(connectionFactory);
        // 设置序列化器
        StringRedisSerializer stringSerializer = new StringRedisSerializer();
        GenericJackson2JsonRedisSerializer jsonSerializer = new GenericJackson2JsonRedisSerializer();
        template.setKeySerializer(stringSerializer);
        template.setHashKeySerializer(stringSerializer);
        template.setValueSerializer(jsonSerializer);
        template.setHashValueSerializer(jsonSerializer);
        template.afterPropertiesSet();
        return template;
    }
}

工具类(IP获取)

package com.example.ratelimiter.utils;
import javax.servlet.http.HttpServletRequest;
/**
 * IP工具类
 */
public class IPUtils {
    /**
     * 获取客户端IP地址
     */
    public static String getClientIp(HttpServletRequest request) {
        String ip = request.getHeader("X-Forwarded-For");
        if (ip == null || ip.isEmpty() || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("Proxy-Client-IP");
        }
        if (ip == null || ip.isEmpty() || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ip == null || ip.isEmpty() || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getRemoteAddr();
        }
        return ip;
    }
}

定时清理任务(可选)

package com.example.ratelimiter.task;
import com.example.ratelimiter.limiter.CounterRateLimiter;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
/**
 * 定时清理任务
 */
@Slf4j
@Component
@RequiredArgsConstructor
public class CleanupTask {
    private final CounterRateLimiter counterRateLimiter;
    /**
     * 每天凌晨2点清理过期数据
     */
    @Scheduled(cron = "0 0 2 * * ?")
    public void cleanupExpiredData() {
        log.info("开始清理限流过期数据");
        counterRateLimiter.cleanup();
        log.info("清理限流过期数据完成");
    }
}

使用示例

package com.example.ratelimiter;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.scheduling.annotation.EnableScheduling;
/**
 * 启动类
 */
@SpringBootApplication
@EnableScheduling
public class RateLimiterApplication {
    public static void main(String[] args) {
        SpringApplication.run(RateLimiterApplication.class, args);
        System.out.println("限流应用启动成功!");
        System.out.println("测试接口:");
        System.out.println("  - http://localhost:8080/api/test/counter   (计数器限流)");
        System.out.println("  - http://localhost:8080/api/test/token     (令牌桶限流)");
        System.out.println("  - http://localhost:8080/api/test/sliding   (滑动窗口限流)");
        System.out.println("  - http://localhost:8080/api/test/normal    (普通接口)");
    }
}

测试脚本(并发测试)

# 使用 curl 并发测试
for i in $(seq 1 200); do
    curl -s -o /dev/null -w "请求$i: HTTP %{http_code}\n" http://localhost:8080/api/test/counter &
done
wait

这个完整的限流案例包含了:

  1. 四种限流算法:计数器、令牌桶、滑动窗口、漏桶
  2. 多种限流实现:单机版(本地内存)和分布式版(Redis)
  3. AOP切面实现:无需修改业务代码,通过注解即可实现限流
  4. 自定义注解:灵活配置限流参数
  5. 全局异常处理:统一处理限流异常
  6. 完整测试示例:包含测试控制器和测试脚本

可以根据实际需求选择合适的限流方式:

  • 单机应用:使用本地内存实现
  • 分布式应用:使用Redis实现
  • 对精度要求高:使用令牌桶或滑动窗口
  • 业务突发流量:使用漏桶算法

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