本篇文章主要来讲Spring Boot 整合 Redisson 实现限流,之前我们讲过使用Redis的Lua脚本方式,我们今天主要讲使用 Redisson 提供的方法实现限流。本文中主要用到 org.redisson.api.RRateLimiter ,它的方法比较多,比如:
pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0modelVersion>
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>2.6.0version>
<relativePath/>
parent>
<groupId>com.aliangroupId>
<artifactId>redis-limit-javaartifactId>
<version>0.0.1-SNAPSHOTversion>
<name>redisCachename>
<description>redis-limit-javadescription>
<properties>
<project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>
<project.package.directory>targetproject.package.directory>
<java.version>1.8java.version>
<jackson.version>2.9.10jackson.version>
<lombok.version>1.16.14lombok.version>
<fastjson.version>1.2.68fastjson.version>
<junit.version>4.12junit.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-aopartifactId>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-data-redisartifactId>
dependency>
<dependency>
<groupId>org.redissongroupId>
<artifactId>redisson-spring-boot-starterartifactId>
<version>3.17.0version>
<exclusions>
<exclusion>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-actuatorartifactId>
exclusion>
exclusions>
dependency>
<dependency>
<groupId>com.fasterxml.jackson.coregroupId>
<artifactId>jackson-databindartifactId>
<version>${jackson.version}version>
dependency>
<dependency>
<groupId>com.fasterxml.jackson.datatypegroupId>
<artifactId>jackson-datatype-jsr310artifactId>
<version>${jackson.version}version>
dependency>
<dependency>
<groupId>com.alibabagroupId>
<artifactId>fastjsonartifactId>
<version>${fastjson.version}version>
dependency>
<dependency>
<groupId>org.apache.commonsgroupId>
<artifactId>commons-lang3artifactId>
<version>3.12.0version>
dependency>
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
<version>${lombok.version}version>
dependency>
dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-maven-pluginartifactId>
plugin>
plugins>
build>
project>
因为我平常一直是使用 SpringBoot2.6.0 这个版本,它整合 redisson-spring-boot-starter 时会有点问题,本文的关键限流使用,不去深究这个问题,直接排除了健康检查就好了
<dependency>
<groupId>org.redissongroupId>
<artifactId>redisson-spring-boot-starterartifactId>
<version>3.17.0version>
<exclusions>
<exclusion>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-actuatorartifactId>
exclusion>
exclusions>
dependency>
application.properties
# 端口
server.port=8090
# 上下文路径
server.servlet.context-path=/rateLimit
# Redis数据库索引(默认为0)
spring.redis.database=0
# Redis服务器地址
#spring.redis.host=192.168.0.193
spring.redis.host=127.0.0.1
# Redis服务器连接端口
spring.redis.port=6379
# Redis服务器连接密码(默认为空)
spring.redis.password=123456
# 连接池最大连接数(使用负值表示没有限制)
spring.redis.jedis.pool.max-active=20
# 连接池中的最小空闲连接
spring.redis.jedis.pool.min-idle=10
# 连接池中的最大空闲连接
spring.redis.jedis.pool.max-idle=20
# 连接池最大阻塞等待时间(使用负值表示没有限制)
spring.redis.jedis.pool.max-wait=20000
# 读时间(毫秒)
spring.redis.timeout=10000
# 连接超时时间(毫秒)
spring.redis.connect-timeout=10000
# redisson配置文件位置
spring.redis.redisson.file=classpath:redisson-single.yml
redisson-single.yml
# 单节点设置
singleServerConfig:
# redis数据库索引
database: 0
# redis地址
address: redis://127.0.0.1:6379
# redis密码
password: 123456
# 连接超时
connectTimeout: 10000
# 读超时
timeout: 3000
# 命令失败重试次数
retryAttempts: 3
# 命令重试发送时间间隔
retryInterval: 1500
# 最小空闲连接数 默认24
connectionMinimumIdleSize: 10
# 连接池大小,默认64
connectionPoolSize: 20
因为我本机redis是单节点的,所以是单节点配置相关的,还有很多配置,大家参照下面这两个类进行配置
如果你是集群模式,则参照下面这三个类进行配置
RedisConfiguration.java
package com.alian.redissonLimit.config;
import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalDateDeserializer;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalDateTimeDeserializer;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalTimeDeserializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateSerializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateTimeSerializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalTimeSerializer;
import lombok.extern.slf4j.Slf4j;
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.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.format.DateTimeFormatter;
@Slf4j
@Configuration
public class RedisConfiguration {
/**
* redis配置
*
* @param redisConnectionFactory
* @return
*/
@Bean
public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) {
// 实例化redisTemplate
RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
//设置连接工厂
redisTemplate.setConnectionFactory(redisConnectionFactory);
// key采用String的序列化
redisTemplate.setKeySerializer(keySerializer());
// value采用jackson序列化
redisTemplate.setValueSerializer(valueSerializer());
// Hash key采用String的序列化
redisTemplate.setHashKeySerializer(keySerializer());
// Hash value采用jackson序列化
redisTemplate.setHashValueSerializer(valueSerializer());
//执行函数,初始化RedisTemplate
redisTemplate.afterPropertiesSet();
return redisTemplate;
}
/**
* key类型采用String序列化
*
* @return
*/
private RedisSerializer<String> keySerializer() {
return new StringRedisSerializer();
}
/**
* value采用JSON序列化
*
* @return
*/
private RedisSerializer<Object> valueSerializer() {
//设置jackson序列化
Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<>(Object.class);
//设置序列化对象
jackson2JsonRedisSerializer.setObjectMapper(getMapper());
return jackson2JsonRedisSerializer;
}
/**
* 使用com.fasterxml.jackson.databind.ObjectMapper
* 对数据进行处理包括java8里的时间
*
* @return
*/
private ObjectMapper getMapper() {
ObjectMapper mapper = new ObjectMapper();
//设置可见性
mapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
//默认键入对象
mapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
//设置Java 8 时间序列化
JavaTimeModule timeModule = new JavaTimeModule();
timeModule.addSerializer(LocalDateTime.class, new LocalDateTimeSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
timeModule.addSerializer(LocalDate.class, new LocalDateSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd")));
timeModule.addSerializer(LocalTime.class, new LocalTimeSerializer(DateTimeFormatter.ofPattern("HH:mm:ss")));
timeModule.addDeserializer(LocalDateTime.class, new LocalDateTimeDeserializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
timeModule.addDeserializer(LocalDate.class, new LocalDateDeserializer(DateTimeFormatter.ofPattern("yyyy-MM-dd")));
timeModule.addDeserializer(LocalTime.class, new LocalTimeDeserializer(DateTimeFormatter.ofPattern("HH:mm:ss")));
//禁用把时间转为时间戳
mapper.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false);
mapper.registerModule(timeModule);
return mapper;
}
}
提过很多次了,就是Redis的整合。
RateLimiter.java
package com.alian.redissonLimit.annotate;
import org.redisson.api.RateType;
import java.lang.annotation.*;
@Documented
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface RedissonRateLimiter {
/**
* RRateLimiter 限流模式
* OVERALL 所有客户端加总限流
* PER_CLIENT 每个客户端单独计算流量
*/
RateType mode() default RateType.PER_CLIENT;
/**
* Spel表达式
*/
String[] keys() default {};
/**
* 单位时间产生的令牌数,默认100
*/
long rate() default 100;
/**
* 时间间隔,默认1秒
*/
long rateInterval() default 1;
/**
* 拒绝请求时的提示信息
*/
String showPromptMsg() default "服务器繁忙,请稍候再试";
}
自定义注解也没有什么好说的,主要是定义了:@RateLimiter
RateLimiterAspectHandler.java
package com.alian.redissonLimit.aop;
import com.alian.redissonLimit.annotate.RedissonRateLimiter;
import com.alian.redissonLimit.annotate.RedissonRateLimiters;
import com.alian.redissonLimit.exception.RateLimiterException;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
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.redisson.api.RRateLimiter;
import org.redisson.api.RateIntervalUnit;
import org.redisson.api.RedissonClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.util.DigestUtils;
import java.nio.charset.StandardCharsets;
import java.util.concurrent.TimeUnit;
@Slf4j
@Component
@Aspect
public class RateLimiterAspectHandler {
@Autowired
private RateLimiterKeyProvider keyProvider;
@Autowired
private RedissonClient redissonClient;
@Around(value = "@annotation(redissonRateLimiter)", argNames = "point,redissonRateLimiter")
public Object around(ProceedingJoinPoint point, RedissonRateLimiter redissonRateLimiter) throws Throwable {
isAllow(point, redissonRateLimiter);
return point.proceed();
}
@Around(value = " @annotation(redissonRateLimiters)", argNames = "point,redissonRateLimiters")
public Object around(ProceedingJoinPoint point, RedissonRateLimiters redissonRateLimiters) throws Throwable {
RedissonRateLimiter[] limiters = redissonRateLimiters.value();
for (RedissonRateLimiter rateLimiter : limiters) {
isAllow(point, rateLimiter);
}
return point.proceed();
}
private void isAllow(ProceedingJoinPoint point, RedissonRateLimiter redissonRateLimiter) {
// 获取key
String key = keyProvider.getKey(point, redissonRateLimiter);
// 此处是为了日志输出
boolean flag = StringUtils.isNotBlank(key);
// 类路径+方法,然后计算md5
String uniqueKey = getUniqueKey((MethodSignature) point.getSignature());
// key名称
key = StringUtils.isNotBlank(key) ? uniqueKey + "." + key : uniqueKey;
// 获取RRateLimiter实例
RRateLimiter limiter = redissonClient.getRateLimiter(key);
// 创建令牌桶数据模型,单位时间内产生多少令牌
limiter.trySetRate(redissonRateLimiter.mode(), redissonRateLimiter.rate(), redissonRateLimiter.rateInterval(), RateIntervalUnit.SECONDS);
// 尝试访问数据,timeout 时间内,允许获得的数量permits(如果获取失败,返回false)
// 单位时间内不能获取到1个令牌,则返回,不阻塞
boolean tryAcquire = limiter.tryAcquire(1, redissonRateLimiter.rateInterval(), TimeUnit.SECONDS);
log.info("【{}】请求,线程:【{}】,获取令牌的结果:{}", flag ? "单用户" : "多用户", Thread.currentThread().getName(), tryAcquire);
if (!tryAcquire) {
log.error("限流模式:{}; 限流数量:{}; 限流时间间隔:{}",
redissonRateLimiter.mode().toString(), redissonRateLimiter.rate(), redissonRateLimiter.rateInterval());
throw new RateLimiterException(redissonRateLimiter.showPromptMsg());
}
}
private String getUniqueKey(MethodSignature signature) {
String format = String.format("%s.%s", signature.getDeclaringTypeName(), signature.getMethod().getName());
return DigestUtils.md5DigestAsHex(format.getBytes(StandardCharsets.UTF_8));
}
}
我们这里的两个方法:
RateLimiterKeyProvider.java
package com.alian.redissonLimit.aop;
import com.alian.redissonLimit.annotate.RedissonRateLimiter;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.context.expression.MethodBasedEvaluationContext;
import org.springframework.core.DefaultParameterNameDiscoverer;
import org.springframework.core.ParameterNameDiscoverer;
import org.springframework.expression.EvaluationContext;
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
@Slf4j
@Component
public class RateLimiterKeyProvider {
private ParameterNameDiscoverer discoverer = new DefaultParameterNameDiscoverer();
private ExpressionParser parser = new SpelExpressionParser();
public String getKey(JoinPoint joinPoint, RedissonRateLimiter redissonRateLimiter) {
List<String> keyList = new ArrayList<>();
Method method = getMethod(joinPoint);
List<String> definitionKeys = getSpelDefinitionKey(redissonRateLimiter.keys(), method, joinPoint.getArgs());
keyList.addAll(definitionKeys);
return StringUtils.collectionToDelimitedString(keyList,".","","");
}
private Method getMethod(JoinPoint joinPoint) {
MethodSignature signature = (MethodSignature) joinPoint.getSignature();
Method method = signature.getMethod();
if (method.getDeclaringClass().isInterface()) {
try {
method = joinPoint.getTarget().getClass().getDeclaredMethod(signature.getName(),
method.getParameterTypes());
} catch (Exception e) {
log.error(null,e);
}
}
return method;
}
private List<String> getSpelDefinitionKey(String[] definitionKeys, Method method, Object[] parameterValues) {
List<String> definitionKeyList = new ArrayList<>();
for (String definitionKey : definitionKeys) {
if (definitionKey != null && !definitionKey.isEmpty()) {
EvaluationContext context = new MethodBasedEvaluationContext(null, method, parameterValues, discoverer);
String key = parser.parseExpression(definitionKey).getValue(context).toString();
definitionKeyList.add(key);
}
}
return definitionKeyList;
}
}
RateLimiterException.java
package com.alian.redissonLimit.exception;
public class RateLimiterException extends RuntimeException {
public RateLimiterException(String message) {
super(message);
}
}
自定义异常类,也没啥好说的,下面就是全局异常,为了省篇幅没有把所有的异常都列出来,小伙伴可以自行添加,主要是对我们RateLimiterException 进行处理。
GlobalExceptionHandler.java
package com.alian.redissonLimit.exception;
import com.alian.redissonLimit.dto.ApiResponseDto;
import lombok.extern.slf4j.Slf4j;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;
import org.springframework.web.HttpRequestMethodNotSupportedException;
import org.springframework.web.bind.MissingServletRequestParameterException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.ResponseStatus;
import javax.servlet.http.HttpServletRequest;
@Slf4j
@Component
@ControllerAdvice
public class GlobalExceptionHandler {
@ExceptionHandler
@ResponseBody
@ResponseStatus(HttpStatus.OK)
public ApiResponseDto<?> handle(HttpRequestMethodNotSupportedException exception, HttpServletRequest request) {
return logWarn(request.getRequestURI() + " " + exception.getMessage(), null, ApiResponseDto.errRequestMethod("请求方法错误"));
}
@ExceptionHandler
@ResponseBody
@ResponseStatus(HttpStatus.OK)
public ApiResponseDto handle(MissingServletRequestParameterException exception) {
return logWarn(exception.getMessage(), null, ApiResponseDto.errParam("参数错误"));
}
@ExceptionHandler
@ResponseBody
@ResponseStatus(HttpStatus.OK)
public ApiResponseDto handle(RateLimiterException exception) {
return ApiResponseDto.fail(exception.getMessage());
}
@ExceptionHandler
@ResponseBody
@ResponseStatus(HttpStatus.OK)
public ApiResponseDto handle(Exception exception) {
log.info("异常类:{}", exception.getClass().getCanonicalName());
return logError(null, exception, ApiResponseDto.exception("系统异常"));
}
private static ApiResponseDto logWarn(String msg, Exception e, ApiResponseDto responseDto) {
long timestamp = responseDto.getTimestamp();
String m = "timestamp is " + timestamp;
if (msg != null) {
m += ", " + msg;
}
if (e == null) {
log.warn(m);
} else {
log.warn(m, e);
}
return responseDto;
}
private static ApiResponseDto logError(String msg, Exception e, ApiResponseDto responseDto) {
long timestamp = responseDto.getTimestamp();
String m = "timestamp is " + timestamp;
if (msg != null) {
m += ", " + msg;
}
log.error(m, e);
return responseDto;
}
}
对应的统一返回封装如下:
ApiResponseDto.java
package com.alian.redissonLimit.dto;
import lombok.*;
import lombok.experimental.Accessors;
@Setter
@Getter
@Accessors(chain = true)
@NoArgsConstructor
@AllArgsConstructor
@ToString(exclude = "content")
public class ApiResponseDto<T> {
/** 成功 */
public static String CODE_SUCCESS="0000";
/** 失败 */
public static String CODE_FAIL="1000";
/** 系统异常 */
public static String CODE_EXCEPTION="1001";
/** 签名错误 */
public static String CODE_ERR_SIGN="1002";
/** 参数错误 */
public static String CODE_ERR_PARAM="1003";
/** 业务异常 */
public static String CODE_BIZ_ERR="1004";
/** 查询无数据,使用明确的参数(如id)进行查询时未找到记录时返回此错误码 */
public static String CODE_NO_DATA="1005";
/** 错误的请求方法 */
public static String CODE_ERR_REQUEST_METHOD="1006";
/** 错误的请求内容类型 */
public static String CODE_ERR_CONTENT_TYPE="1007";
/** 系统繁忙 */
public static String CODE_SYS_BUSY="1008";
/** 显示提示 */
public static String CODE_SHOW_TIP="1009";
/** 根据bizCode进行处理 */
public static String CODE_DEAL_BIZ_CODE="1012";
/** 未找到请求 */
public static String CODE_NOT_FOUND_CODE="1013";
public final static ApiResponseDto SUCCESS=new ApiResponseDto();
private String code =CODE_SUCCESS;
/** 状态说明 */
private String msg ="success";
/** 请求是否成功 */
public boolean isSuccess(){
return CODE_SUCCESS.equals(code);
}
/** 结果内容 */
private T content;
/** 时间戳 */
private long timestamp=System.currentTimeMillis();
/** 业务状态码,由业务接口定义 */
private String bizCode;
/** 业务状态说明 */
private String bizMsg;
public ApiResponseDto(T content) {
this.content=content;
}
public static <T> ApiResponseDto<T> success(){
return SUCCESS;
}
public static <T> ApiResponseDto<T> success(T content){
return new ApiResponseDto<T>(content);
}
public static <T> ApiResponseDto<T> fail(String msg){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_FAIL);
response.setMsg(msg);
return response;
}
public static <T> ApiResponseDto<T> exception(String msg){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_EXCEPTION);
response.setMsg(msg);
return response;
}
public static <T> ApiResponseDto<T> errSign(String msg){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_ERR_SIGN);
response.setMsg(msg);
return response;
}
public static <T> ApiResponseDto<T> errParam(String msg){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_ERR_PARAM);
response.setMsg(msg);
return response;
}
public static <T> ApiResponseDto<T> bizErr(String msg){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_BIZ_ERR);
response.setMsg(msg);
return response;
}
public static <T> ApiResponseDto<T> notFound(String msg){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_NOT_FOUND_CODE);
response.setMsg(msg);
return response;
}
public static <T> ApiResponseDto<T> noData(String msg){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_NO_DATA);
response.setMsg(msg);
return response;
}
public static <T> ApiResponseDto<T> errRequestMethod(String msg){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_ERR_REQUEST_METHOD);
response.setMsg(msg);
return response;
}
public static <T> ApiResponseDto<T> errContentType(){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_ERR_CONTENT_TYPE);
response.setMsg("错误的请求内容类型");
return response;
}
public static <T> ApiResponseDto<T> sysBusy(){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_SYS_BUSY);
response.setMsg("系统繁忙");
return response;
}
public static <T> ApiResponseDto<T> showTip(String tip){
ApiResponseDto<T> response = new ApiResponseDto<>();
response.setCode(CODE_SHOW_TIP);
response.setMsg(tip);
return response;
}
public ApiResponseDto<T> bizInfo(String bizCode,String bizMsg){
this.code=bizCode;
this.msg=bizMsg;
return this;
}
public static <T> ApiResponseDto<T> dealBizCode(String bizCode,String bizMsg,T content){
ApiResponseDto<T> response = new ApiResponseDto<>(content);
response.setCode(CODE_DEAL_BIZ_CODE);
response.setMsg("根据bizCode进行处理");
response.setBizCode(bizCode);
response.setBizMsg(bizMsg);
return response;
}
}
UserController.java
package com.alian.redissonLimit.controller;
import com.alian.redissonLimit.annotate.RedissonRateLimiter;
import com.alian.redissonLimit.annotate.RedissonRateLimiters;
import com.alian.redissonLimit.dto.ApiResponseDto;
import com.alian.redissonLimit.dto.UserDto;
import lombok.extern.slf4j.Slf4j;
import org.redisson.api.RateType;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.time.LocalDateTime;
import java.util.HashMap;
import java.util.Map;
@Slf4j
@RequestMapping("/user")
@RestController
public class UserController {
private static Map<String, UserDto> map = new HashMap<String, UserDto>() {{
put("BAT001", new UserDto("BAT001", "梁南生", 27, "研发部", 18000.0, LocalDateTime.of(2020, 5, 20, 9, 0, 0)));
put("BAT002", new UserDto("BAT002", "包雅馨", 25, "财务部", 8800.0, LocalDateTime.of(2016, 11, 10, 8, 30, 0)));
put("BAT003", new UserDto("BAT003", "罗考聪", 35, "测试部", 6400.0, LocalDateTime.of(2017, 3, 20, 14, 0, 0)));
}};
@RedissonRateLimiters(value = {
@RedissonRateLimiter(keys = {"#id"}, mode = RateType.OVERALL, rate = 1, rateInterval = 1, showPromptMsg = "您查询太快了,请稍后再试"),
@RedissonRateLimiter(mode = RateType.OVERALL, rate = 3, rateInterval = 1, showPromptMsg = "系统繁忙,请稍后再试")
})
@RequestMapping("/findById/{id}")
public ApiResponseDto<UserDto> findById(@PathVariable("id") String id) {
UserDto userDto = map.getOrDefault(id, null);
if (userDto != null) {
return ApiResponseDto.success(userDto);
}
return ApiResponseDto.noData("未查询到数据");
}
}
简单模拟根据用户编号查询用户的接口,关键是我们使用注解@RateLimiter 的方法可以做限流,看是否能达到我们的要求。这里有两层意思:
虽说和我们上一篇的设计是一样的,但是得到的结果可能就不一样了,具体的我们来看看测试结果,然后了解下为啥可能会不一样。
写个简单的单元测试方法。
测试方法
package com.alian.redissonLimit;
import com.alian.redissonLimit.controller.UserController;
import com.alian.redissonLimit.dto.ApiResponseDto;
import com.alian.redissonLimit.dto.UserDto;
import lombok.extern.slf4j.Slf4j;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import java.util.concurrent.CountDownLatch;
@Slf4j
@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest
public class RedisLimitTest {
@Autowired
private UserController userController;
@Test
public void singleUserRequest() {
final CountDownLatch countDownLatch = new CountDownLatch(5);
for (int i = 0; i < 5; i++) {
new Thread(() -> {
try {
// 使当前线程在锁存器倒计数至零之前一直等待,除非线程被中断或超出了指定的等待时间。如果当前计数为零,则此方法立刻返回true值
countDownLatch.await();
//获得锁
ApiResponseDto<UserDto> responseDto = userController.findById("BAT001");
log.info("线程【{}】执行完,结果信息:{}", Thread.currentThread().getName(), responseDto.getMsg());
} catch (InterruptedException e) {
e.printStackTrace();
}
}, "Thread" + i).start();
// 递减锁存器的计数,如果计数到达零,则释放所有等待的线程。如果当前计数大于零,则将计数减少.
countDownLatch.countDown();
}
try {
Thread.sleep(10000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
单用户后台结果1:
11:39:17 953 INFO [Thread3]:【单用户】请求,线程:【Thread3】,获取令牌的结果:true
11:39:17 953 INFO [Thread3]:【多用户】请求,线程:【Thread3】,获取令牌的结果:true
11:39:17 963 INFO [Thread3]:线程【Thread3】执行完,结果信息:success
11:39:18 969 INFO [Thread2]:【单用户】请求,线程:【Thread2】,获取令牌的结果:false
11:39:18 969 INFO [Thread1]:【单用户】请求,线程:【Thread1】,获取令牌的结果:false
11:39:18 969 INFO [Thread4]:【单用户】请求,线程:【Thread4】,获取令牌的结果:false
11:39:18 969 INFO [Thread0]:【单用户】请求,线程:【Thread0】,获取令牌的结果:false
11:39:18 969 ERROR [Thread1]:限流模式:OVERALL; 限流数量:1; 限流时间间隔:1
11:39:18 969 ERROR [Thread4]:限流模式:OVERALL; 限流数量:1; 限流时间间隔:1
11:39:18 969 ERROR [Thread2]:限流模式:OVERALL; 限流数量:1; 限流时间间隔:1
11:39:18 969 ERROR [Thread0]:限流模式:OVERALL; 限流数量:1; 限流时间间隔:1
从上面的结果我们可以看到同时1秒内同时接收5个请求,只有1个请求拿到了令牌,我们之前就说了,可能结果还能不同,我们这里的间隔是1秒钟,但是如果我们把获取令牌的时间改成2秒呢?
boolean tryAcquire = limiter.tryAcquire(1, redissonRateLimiter.rateInterval(), TimeUnit.SECONDS);
如果改成
boolean tryAcquire = limiter.tryAcquire(1, 2, TimeUnit.SECONDS);
单用户后台结果2:
13:19:43 617 INFO [Thread4]:【单用户】请求,线程:【Thread4】,获取令牌的结果:true
13:19:43 623 INFO [Thread4]:线程【Thread4】执行完,结果信息:success
13:19:44 627 INFO [Thread3]:【单用户】请求,线程:【Thread3】,获取令牌的结果:true
13:19:44 627 INFO [Thread3]:线程【Thread3】执行完,结果信息:success
13:19:45 617 INFO [Thread1]:【单用户】请求,线程:【Thread1】,获取令牌的结果:false
13:19:45 617 INFO [Thread0]:【单用户】请求,线程:【Thread0】,获取令牌的结果:false
13:19:45 617 INFO [Thread2]:【单用户】请求,线程:【Thread2】,获取令牌的结果:false
13:19:45 617 ERROR [Thread1]:限流模式:OVERALL; 限流数量:1; 限流时间间隔:1
13:19:45 617 ERROR [Thread2]:限流模式:OVERALL; 限流数量:1; 限流时间间隔:1
13:19:45 617 ERROR [Thread0]:限流模式:OVERALL; 限流数量:1; 限流时间间隔:1
从这里我们可以看到单用户请求5次,最后有2个拿到了令牌,tryAcquire(1, 2, TimeUnit.SECONDS),这个意思就是在2秒内获取1个令牌即可,虽说第一秒只有1个令牌,但是到第二秒内又产生了1个令牌,所以5个请求,有2个请求拿到了令牌。其实这种也有一定的好处,就是先请求进来的,有一定的概率会分配到锁,也就是先到先得的概率大一点,类似在排队一样。
我们还是把上面的修改,改回去(tryAcquire(1, redissonRateLimiter.rateInterval(), TimeUnit.SECONDS))。
测试方法
package com.alian.redissonLimit;
import com.alian.redissonLimit.controller.UserController;
import com.alian.redissonLimit.dto.ApiResponseDto;
import com.alian.redissonLimit.dto.UserDto;
import lombok.extern.slf4j.Slf4j;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import java.util.concurrent.CountDownLatch;
@Slf4j
@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest
public class RedisLimitTest {
@Autowired
private UserController userController;
@Test
public void multiUserRequest() {
final CountDownLatch countDownLatch = new CountDownLatch(5);
for (int i = 1; i < 6; i++) {
String id = "BAT00" + i;
new Thread(() -> {
try {
// 使当前线程在锁存器倒计数至零之前一直等待,除非线程被中断或超出了指定的等待时间。如果当前计数为零,则此方法立刻返回true值
countDownLatch.await();
//获得锁
ApiResponseDto<UserDto> responseDto = userController.findById(id);
log.info("线程【{}】执行完,结果信息:{}", Thread.currentThread().getName(), responseDto.getMsg());
} catch (InterruptedException e) {
e.printStackTrace();
}
}, "Thread" + i).start();
// 递减锁存器的计数,如果计数到达零,则释放所有等待的线程。如果当前计数大于零,则将计数减少.
countDownLatch.countDown();
}
try {
Thread.sleep(10000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
我们测试方法是5个用户,5个线程同时请求我们的接口,所以单用户限流都是能拿到令牌的,5个请求都拿到了令牌,而接口限流是每秒3个令牌,所以有2个触发了限流。
单用户后台结果1:
13:38:02 763 INFO [Thread4]:【单用户】请求,线程:【Thread4】,获取令牌的结果:true
13:38:02 763 INFO [Thread1]:【单用户】请求,线程:【Thread1】,获取令牌的结果:true
13:38:02 763 INFO [Thread2]:【单用户】请求,线程:【Thread2】,获取令牌的结果:true
13:38:02 763 INFO [Thread5]:【单用户】请求,线程:【Thread5】,获取令牌的结果:true
13:38:02 763 INFO [Thread3]:【单用户】请求,线程:【Thread3】,获取令牌的结果:true
13:38:02 764 INFO [Thread5]:【多用户】请求,线程:【Thread5】,获取令牌的结果:true
13:38:02 764 INFO [Thread4]:【多用户】请求,线程:【Thread4】,获取令牌的结果:true
13:38:02 764 INFO [Thread2]:【多用户】请求,线程:【Thread2】,获取令牌的结果:true
13:38:02 768 INFO [Thread5]:线程【Thread5】执行完,结果信息:未查询到数据
13:38:02 768 INFO [Thread2]:线程【Thread2】执行完,结果信息:success
13:38:02 768 INFO [Thread4]:线程【Thread4】执行完,结果信息:未查询到数据
13:38:03 777 INFO [Thread1]:【多用户】请求,线程:【Thread1】,获取令牌的结果:false
13:38:03 777 INFO [Thread3]:【多用户】请求,线程:【Thread3】,获取令牌的结果:false
13:38:03 777 ERROR [Thread1]:限流模式:OVERALL; 限流数量:3; 限流时间间隔:1
13:38:03 777 ERROR [Thread3]:限流模式:OVERALL; 限流数量:3; 限流时间间隔:1
从结果上可以看出,先是用户限流执行,然后接口限流执行。其实这里还和我们的注解顺序有关系,如果我们把com.alian.redissonLimit.controller的 findById 方法上面的组合注解
@RedissonRateLimiters(value = {
@RedissonRateLimiter(keys = {"#id"}, mode = RateType.OVERALL, rate = 1, rateInterval = 1, showPromptMsg = "您查询太快了,请稍后再试"),
@RedissonRateLimiter(mode = RateType.OVERALL, rate = 3, rateInterval = 1, showPromptMsg = "系统繁忙,请稍后再试")
})
改成(注解顺序改变)
@RedissonRateLimiters(value = {
@RedissonRateLimiter(mode = RateType.OVERALL, rate = 3, rateInterval = 1, showPromptMsg = "系统繁忙,请稍后再试"),
@RedissonRateLimiter(keys = {"#id"}, mode = RateType.OVERALL, rate = 1, rateInterval = 1, showPromptMsg = "您查询太快了,请稍后再试")
})
单用户后台结果2:
13:40:18 786 INFO [Thread3]:【多用户】请求,线程:【Thread3】,获取令牌的结果:true
13:40:18 786 INFO [Thread5]:【多用户】请求,线程:【Thread5】,获取令牌的结果:true
13:40:18 786 INFO [Thread4]:【多用户】请求,线程:【Thread4】,获取令牌的结果:true
13:40:18 805 INFO [Thread4]:【单用户】请求,线程:【Thread4】,获取令牌的结果:true
13:40:18 805 INFO [Thread5]:【单用户】请求,线程:【Thread5】,获取令牌的结果:true
13:40:18 805 INFO [Thread3]:【单用户】请求,线程:【Thread3】,获取令牌的结果:true
13:40:18 807 INFO [Thread4]:线程【Thread4】执行完,结果信息:未查询到数据
13:40:18 807 INFO [Thread3]:线程【Thread3】执行完,结果信息:success
13:40:18 807 INFO [Thread5]:线程【Thread5】执行完,结果信息:未查询到数据
13:40:19 797 INFO [Thread2]:【多用户】请求,线程:【Thread2】,获取令牌的结果:false
13:40:19 797 INFO [Thread1]:【多用户】请求,线程:【Thread1】,获取令牌的结果:false
13:40:19 797 ERROR [Thread2]:限流模式:OVERALL; 限流数量:3; 限流时间间隔:1
13:40:19 797 ERROR [Thread1]:限流模式:OVERALL; 限流数量:3; 限流时间间隔:1
从结果上可以看出,先是接口限流执行,然后用户限流执行,和之前的执行顺序相比就是相反的了。
所以还是建议使用我之前介绍的采用Lua脚本:Spring Boot 整合Redis使用Lua脚本实现限流