Springboot + redis + 注解 + 拦截器来实现接口幂等性校验

一：幂等性介绍：通俗的说就是一个接口, 多次发起同一个请求, 必须保证操作只能执行一次

比如:

• 订单接口, 不能多次创建订单

• 支付接口, 重复支付同一笔订单只能扣一次钱

• 支付宝回调接口, 可能会多次回调, 必须处理重复回调

• 普通表单提交接口, 因为网络超时等原因多次点击提交, 只能成功一次。。。。

二: 常见解决方案

• 唯一索引 -- 防止新增脏数据

• token机制 -- 防止页面重复提交

• 悲观锁 -- 获取数据的时候加锁(锁表或锁行)

• 乐观锁 -- 基于版本号version实现, 在更新数据那一刻校验数据

• 分布式锁 -- redis(jedis、redisson)或zookeeper实现

• 状态机 -- 状态变更, 更新数据时判断状态

• redis + token机制实现接口幂等性校验

三：实现思路

为需要保证幂等性的每一次请求创建一个唯一标识token, 先获取token, 并将此token存入redis, 请求接口时, 将此token放到header或者作为请求参数请求接口, 后端接口判断redis中是否存在此token:

• 如果存在, 正常处理业务逻辑, 并从redis中删除此token, 那么, 如果是重复请求, 由于token已被删除, 则不能通过校验, 返回请勿重复操作提示。。。

• 如果不存在, 说明参数不合法或者是重复请求, 返回提示即可。。。

四: 项目框架及

• springboot

• redis

• @ApiIdempotent注解 + 拦截器对请求进行拦截

• @ControllerAdvice全局异常处理
• 压测工具: jmeter

五: 实现

       pom.xml 

<?xml version="1.0" encoding="UTF-8"?>
<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>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.5.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.yw.redis</groupId>
    <artifactId>idempotency</artifactId>
    <version>1.0.0</version>
    <name>idempotency</name>
    <description>Springboot + redis + 注解 + 拦截器来实现接口幂等性校验</description>

    <properties>
        <java.version>1.8</java.version>
        <jedis.version>2.9.0</jedis.version>
    </properties>

    <dependencies>
        <!--WEB-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</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>

        <!--redisson-->
        <dependency>
            <groupId>org.redisson</groupId>
            <artifactId>redisson</artifactId>
            <version>3.6.5</version>
        </dependency>
        <!-- Redis-Jedis -->
        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
            <version>${jedis.version}</version>
        </dependency>

        <!--mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.0.0</version>
        </dependency>
        <!--mysql connector-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

        <!--lombok-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.10</version>
        </dependency>
        <!-- commons-lang3 -->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.4</version>
        </dependency>
        <!-- springboot-aop -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>
        <!-- guava -->
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>26.0-jre</version>
        </dependency>
        <!--joda time-->
        <dependency>
            <groupId>joda-time</groupId>
            <artifactId>joda-time</artifactId>
            <version>2.10</version>
        </dependency>
        <!--mq-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>
        <!--mail-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-collections4</artifactId>
            <version>4.1</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.20</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>

        <!-- 如果不添加此节点mybatis的mapper.xml文件都会被漏掉。 -->
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.*</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.*</include>
                </includes>
            </resource>
        </resources>
    </build>

    <repositories>
        <repository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>https://repo.spring.io/snapshot</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </repository>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
        </repository>
    </repositories>
    <pluginRepositories>
        <pluginRepository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>https://repo.spring.io/snapshot</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </pluginRepository>
        <pluginRepository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
        </pluginRepository>
    </pluginRepositories>
</project>

JedisUtil

package com.yw.redis.utils;

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
@Component
@Slf4j
public class JedisUtil {
    @Autowired
    private JedisPool jedisPool;

    private Jedis getJedis() {
        return jedisPool.getResource();
    }

    /**
     * 设值
     *
     * @param key
     * @param value
     * @return
     */
    public String set(String key, String value) {
        Jedis jedis = null;
        try {
            jedis = getJedis();
            return jedis.set(key, value);
        } catch (Exception e) {
            log.error("set key:{} value:{} error", key, value, e);
            return null;
        } finally {
            close(jedis);
        }
    }

    /**
     * 设值
     *
     * @param key
     * @param value
     * @param expireTime 过期时间, 单位: s
     * @return
     */
    public String set(String key, String value, int expireTime) {
        Jedis jedis = null;
        try {
            jedis = getJedis();
            return jedis.setex(key, expireTime, value);
        } catch (Exception e) {
            log.error("set key:{} value:{} expireTime:{} error", key, value, expireTime, e);
            return null;
        } finally {
            close(jedis);
        }
    }

    /**
     * 取值
     *
     * @param key
     * @return
     */
    public String get(String key) {
        Jedis jedis = null;
        try {
            jedis = getJedis();
            return jedis.get(key);
        } catch (Exception e) {
            log.error("get key:{} error", key, e);
            return null;
        } finally {
            close(jedis);
        }
    }

    /**
     * 删除key
     *
     * @param key
     * @return
     */
    public Long del(String key) {
        Jedis jedis = null;
        try {
            jedis = getJedis();
            return jedis.del(key.getBytes());
        } catch (Exception e) {
            log.error("del key:{} error", key, e);
            return null;
        } finally {
            close(jedis);
        }
    }

    /**
     * 判断key是否存在
     *
     * @param key
     * @return
     */
    public Boolean exists(String key) {
        Jedis jedis = null;
        try {
            jedis = getJedis();
            return jedis.exists(key.getBytes());
        } catch (Exception e) {
            log.error("exists key:{} error", key, e);
            return null;
        } finally {
            close(jedis);
        }
    }

    /**
     * 设值key过期时间
     *
     * @param key
     * @param expireTime 过期时间, 单位: s
     * @return
     */
    public Long expire(String key, int expireTime) {
        Jedis jedis = null;
        try {
            jedis = getJedis();
            return jedis.expire(key.getBytes(), expireTime);
        } catch (Exception e) {
            log.error("expire key:{} error", key, e);
            return null;
        } finally {
            close(jedis);
        }
    }

    /**
     * 获取剩余时间
     *
     * @param key
     * @return
     */
    public Long ttl(String key) {
        Jedis jedis = null;
        try {
            jedis = getJedis();
            return jedis.ttl(key);
        } catch (Exception e) {
            log.error("ttl key:{} error", key, e);
            return null;
        } finally {
            close(jedis);
        }
    }

    private void close(Jedis jedis) {
        if (null != jedis) {
            jedis.close();
        }
    }
}

自定义注解@ApiIdempotent

package com.yw.redis.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * 在需要保证 接口幂等性 的Controller的方法上使用此注解
 */
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface ApiIdempotent {
}

ApiIdempotentInterceptor拦截器

package com.yw.redis.interceptor;

import com.yw.redis.annotation.ApiIdempotent;
import com.yw.redis.service.TokenService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.messaging.handler.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;


/**
 * 接口幂等性拦截器
 */
public class ApiIdempotentInterceptor implements HandlerInterceptor {
    @Autowired
    private TokenService tokenService;
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {
        if (!(handler instanceof HandlerMethod)) {
            return true;
        }

        HandlerMethod handlerMethod = (HandlerMethod) handler;
        Method method = handlerMethod.getMethod();

        ApiIdempotent methodAnnotation = method.getAnnotation(ApiIdempotent.class);
        if (methodAnnotation != null) {
            check(request);// 幂等性校验, 校验通过则放行, 校验失败则抛出异常, 并通过统一异常处理返回友好提示
        }

        return true;
    }

    private void check(HttpServletRequest request) {
        tokenService.checkToken(request);
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
    }
}

　　TokenServiceImpl

package com.yw.redis.service.impl;

import com.yw.redis.common.Constant;
import com.yw.redis.common.ResponseCode;
import com.yw.redis.common.ServerResponse;
import com.yw.redis.exception.ServiceException;
import com.yw.redis.service.TokenService;
import com.yw.redis.utils.JedisUtil;
import com.yw.redis.utils.RandomUtil;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.text.StrBuilder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import javax.servlet.http.HttpServletRequest;
@Service
public class TokenServiceImpl implements TokenService {


    private static final String TOKEN_NAME = "token";
    @Autowired
    private JedisUtil jedisUtil;

    @Override
    public ServerResponse createToken() {
        String str = RandomUtil.UUID32();
        StrBuilder token = new StrBuilder();
        token.append(Constant.Redis.TOKEN_PREFIX).append(str);

        jedisUtil.set(token.toString(), token.toString(), Constant.Redis.EXPIRE_TIME_MINUTE);

        return ServerResponse.success(token.toString());
    }

    @Override
    public void checkToken(HttpServletRequest request) {
        String token = request.getHeader(TOKEN_NAME);
        if (StringUtils.isBlank(token)) {// header中不存在token
            token = request.getParameter(TOKEN_NAME);
            if (StringUtils.isBlank(token)) {// parameter中也不存在token
                throw new ServiceException(ResponseCode.ILLEGAL_ARGUMENT.getMsg());
            }
        }

        if (!jedisUtil.exists(token)) {
            throw new ServiceException(ResponseCode.REPETITIVE_OPERATION.getMsg());
        }

        Long del = jedisUtil.del(token);
        if (del <= 0) {
            throw new ServiceException(ResponseCode.REPETITIVE_OPERATION.getMsg());
        }
    }
}　

IdempotencyApplication

package com.yw.redis;

import com.yw.redis.interceptor.AccessLimitInterceptor;
import com.yw.redis.interceptor.ApiIdempotentInterceptor;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
import org.springframework.web.filter.CorsFilter;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@SpringBootApplication
@MapperScan("com.yw.redis.mapper")
@EnableScheduling
public class IdempotencyApplication extends WebMvcConfigurerAdapter {

    public static void main(String[] args) {
        SpringApplication.run(IdempotencyApplication.class, args);
    }
    /**
     * 跨域
     * @return
     */
    @Bean
    public CorsFilter corsFilter() {
        final UrlBasedCorsConfigurationSource urlBasedCorsConfigurationSource = new UrlBasedCorsConfigurationSource();
        final CorsConfiguration corsConfiguration = new CorsConfiguration();
        corsConfiguration.setAllowCredentials(true);
        corsConfiguration.addAllowedOrigin("*");
        corsConfiguration.addAllowedHeader("*");
        corsConfiguration.addAllowedMethod("*");
        urlBasedCorsConfigurationSource.registerCorsConfiguration("/**", corsConfiguration);
        return new CorsFilter(urlBasedCorsConfigurationSource);
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        // 接口幂等性拦截器
        registry.addInterceptor(apiIdempotentInterceptor());
        // 接口防刷限流拦截器
        registry.addInterceptor(accessLimitInterceptor());

        super.addInterceptors(registry);
    }

    @Bean
    public ApiIdempotentInterceptor apiIdempotentInterceptor() {
        return new ApiIdempotentInterceptor();
    }

    @Bean
    public AccessLimitInterceptor accessLimitInterceptor() {
        return new AccessLimitInterceptor();
    }

}

六: 测试

1、获取token的控制器TokenController

package com.yw.redis.controller;


import com.yw.redis.common.ServerResponse;
import com.yw.redis.service.TokenService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/token")
public class TokenController {

    @Autowired
    private TokenService tokenService;

    @GetMapping
    public ServerResponse token() {
        return tokenService.createToken();
    }

}

　　2、TestController, 注意@ApiIdempotent注解, 在需要幂等性校验的方法上声明此注解即可, 不需要校验的无影响

package com.yw.redis.controller;

import com.google.common.collect.Lists;

import com.yw.redis.annotation.AccessLimit;
import com.yw.redis.annotation.ApiIdempotent;
import com.yw.redis.common.ServerResponse;
import com.yw.redis.mapper.MsgLogMapper;
import com.yw.redis.mapper.UserMapper;
import com.yw.redis.pojo.Mail;
import com.yw.redis.pojo.User;
import com.yw.redis.service.TestService;
import com.yw.redis.service.batch.mapperproxy.MapperProxy;
import com.yw.redis.utils.RandomUtil;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.scheduling.annotation.Async;
import org.springframework.validation.Errors;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
@RequestMapping("/test")
@Slf4j
public class TestController {

    @Autowired
    private TestService testService;

    @Autowired
    private UserMapper userMapper;

    @Autowired
    private MsgLogMapper msgLogMapper;

    @ApiIdempotent
    @PostMapping("testIdempotence")
    public ServerResponse testIdempotence() {
        return testService.testIdempotence();
    }

    @AccessLimit(maxCount = 5, seconds = 5)
    @PostMapping("accessLimit")
    public ServerResponse accessLimit() {
        return testService.accessLimit();
    }

    @PostMapping("send")
    public ServerResponse sendMail(@Validated Mail mail, Errors errors) {
        if (errors.hasErrors()) {
            String msg = errors.getFieldError().getDefaultMessage();
            return ServerResponse.error(msg);
        }

        return testService.send(mail);
    }

    @PostMapping("single")
    public ServerResponse single(int size) {
        List<User> list = Lists.newArrayList();

        for (int i = 0; i < size; i++) {
            String str = RandomUtil.UUID32();
            User user = User.builder().username(str).password(str).build();
            list.add(user);
        }

        long startTime = System.nanoTime();
        log.info("batch insert costs: {} ms", (System.nanoTime() - startTime) / 1000000);

        return ServerResponse.success();
    }

    @PostMapping("batchInsert")
    public ServerResponse batchInsert(int size) {
        List<User> list = Lists.newArrayList();

        for (int i = 0; i < size; i++) {
            String str = RandomUtil.UUID32();
            User user = User.builder().username(str).password(str).build();
            list.add(user);
        }

        new MapperProxy<User>(userMapper).batchInsert(list);

        return ServerResponse.success();
    }

    @PostMapping("batchUpdate")
    public ServerResponse batchUpdate(String ids) {
        List<User> list = Lists.newArrayList();

        String[] split = ids.split(",");
        for (String id : split) {
            User user = User.builder().id(Integer.valueOf(id)).username("batchUpdate_" + RandomUtil.UUID32()).password("123456").build();
            list.add(user);
        }

        new MapperProxy<User>(userMapper).batchUpdate(list);

        return ServerResponse.success();
    }

    @PostMapping("sync")
    public ServerResponse sync() {
        List<User> list = Lists.newArrayList();
        for (int i = 0; i < 300; i++) {
            String uuid32 = RandomUtil.UUID32();
            User user = User.builder().username(uuid32).password(uuid32).password2(uuid32).password3(uuid32)
                    .password4(uuid32).password5(uuid32).password6(uuid32).password7(uuid32)
                    .password8(uuid32).password9(uuid32).password10(uuid32).build();
            list.add(user);
        }

        userMapper.batchInsert(list);

        check(list);

        return ServerResponse.success();
    }

    @Async
    public void check(List<User> list) {
        String username = list.get(list.size() - 1).getUsername();
        User user = userMapper.selectByUsername(username);
        log.info(user.getUsername());
    }

}

　　ok 则使用localhost:端口/token  就有返回值了

可以 git@github.com:yuanweiGit/SpringbootRedis.git 下载代码