????? ??? ?? Tian ?????

?? ??? ?? ?? ???? ?? ?, ????? ???? ??? ?????? ???? ?? ?? ??? ??? ??? ??? ? ? ? ??.

? ?? ? ?? ??????.

1. ???? ?? Imdempotence? ???? ??? ??? ??? ?? ? ???? ????????. . ??? ? ?? ??? ? ??? ???. ?:

• ?? ?????, ??? ?? ? ??? ? ????
• ?? ?????, ??? ??? ?? ?? ??? ? ?? ??? ? ????.
• Alipay ?? ?????, ?? ??? ?? ? ??? ?? ??? ???? ???
• ???? ?? ?? ?????? ???? ?? ?? ? ?? ??? ?? ??? ?? ?? ??? ? ??? ? ?? ??? ? ????.
  ?? ???--??? ?? ??? ??

?? ????--???? ??? ?? ????? ??--??? ?? ? ??(??? ?? ?? ? ??)

1. ??? ??-??? ?? ?? ???? ??? ???? ? ???? ????? ??
2. ?? ?? - redis(jedis, redisson) ?? Zookeeper ??
3. ?? ?? - ?? ??, ??? ???? ? ?? ??
3. ? ??? ??
6. ? ????? ? ?? ?? ??, ?
   ????? ?? ????? ??? ??? ???? ??? ?????.

   4. ?? ????

   ???? ???? ?? ? ??? ?? ?? ???? ????token, 先獲取token, 并將此token存入redis, 請求接口時(shí), 將此token放到header或者作為請求參數(shù)請求接口, 后端接口判斷redis中是否存在此token:

   • ???? ?? ???? ??? ????? ???? redis??, ??? ???? ??? ??? ? ??? ??? ???? ???Prompttoken, 那么, 如果是重復(fù)請求, 由于token已被刪除, 則不能通過校驗(yàn), 返回請勿重復(fù)操作提示
   • 如果不存在, 說明參數(shù)不合法或者是重復(fù)請求, 返回提示即可

   五、項(xiàng)目簡介

   • Spring Boot
   • Redis
   • @ApiIdempotent注解 + 攔截器對請求進(jìn)行攔截
   • @ControllerAdvice全局異常處理
   • 壓測工具: Jmeter
   ???? ??? ????? ????? ?? ????? ????? ?? ?????. ????

   5. ???? ??

   ????? ??????????Redis????????@ApiIdempotent ?? + ????? ??? ????? ????????@ControllerAdvice?? ?? ?????????????? ??? ??: Jmeter??????????:??????? ??? ??? ??? ???. ???? ?? ??, Spring Boot Redis, ServerResponse, ResponseCode ? ?? ?? ?? ??? ?? ?? ??? ? ??? ??? ?????.??

   六、代碼實(shí)現(xiàn)

   1、maven依賴maven依賴

   <!-- Redis-Jedis -->
   <dependency>
      <groupId>redis.clients</groupId>
      <artifactId>jedis</artifactId>
      <version>2.9.0</version>
   </dependency>
   
   <!--lombok 本文用到@Slf4j注解, 也可不引用, 自定義log即可-->
   <dependency>
       <groupId>org.projectlombok</groupId>
       <artifactId>lombok</artifactId>
       <version>1.16.10</version>
   </dependency>

   2、JedisUtil

   @Component
   @Slf4j
   public class JedisUtil {
   
       @Autowired
       private JedisPool jedisPool;
   
       private Jedis getJedis() {
           return jedisPool.getResource();
       }
   
       /**
        * 設(shè)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);
           }
       }
   
       /**
        * 設(shè)值
        *
        * @param key
        * @param value
        * @param expireTime 過期時(shí)間, 單位: 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);
           }
       }
   
       /**
        * 刪除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);
           }
       }
   
       /**
        * 判斷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);
           }
       }
   
       /**
        * 設(shè)值key過期時(shí)間
        *
        * @param key
        * @param expireTime 過期時(shí)間, 單位: 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);
           }
       }
   
       /**
        * 獲取剩余時(shí)間
        *
        * @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();
           }
       }
   
   }

   3、自定義注解@ApiIdempotent

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

   4、ApiIdempotentInterceptor 攔截器

   /**
    * 接口冪等性攔截器
    */
   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);// 冪等性校驗(yàn), 校驗(yàn)通過則放行, 校驗(yàn)失敗則拋出異常, 并通過統(tǒng)一異常處理返回友好提示
           }
   
           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 {
       }
   }

   5、TokenServiceImpl

   @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());
           }
       }
   
   }

   6、TestApplication

   @SpringBootApplication
   @MapperScan("com.wangzaiplus.test.mapper")
   public class TestApplication  extends WebMvcConfigurerAdapter {
   
       public static void main(String[] args) {
           SpringApplication.run(TestApplication.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) {
           // 接口冪等性攔截器
           registry.addInterceptor(apiIdempotentInterceptor());
           super.addInterceptors(registry);
       }
   
       @Bean
       public ApiIdempotentInterceptor apiIdempotentInterceptor() {
           return new ApiIdempotentInterceptor();
       }
   
   }

   好了，以上便是代碼的實(shí)現(xiàn)部分，下面我們就來驗(yàn)證一下。

   七、測試驗(yàn)證

   獲取token的控制器TokenController

   @RestController
   @RequestMapping("/token")
   public class TokenController {
   
       @Autowired
       private TokenService tokenService;
   
       @GetMapping
       public ServerResponse token() {
           return tokenService.createToken();
       }
   
   }

   2、JedisUtil??

   @RestController
   @RequestMapping("/test")
   @Slf4j
   public class TestController {
   
       @Autowired
       private TestService testService;
   
       @ApiIdempotent
       @PostMapping("testIdempotence")
       public ServerResponse testIdempotence() {
           return testService.testIdempotence();
       }
   
   }

   ??3、自定義注解@ApiIdempotent??rrreee??4、ApiIdempotentInterceptor ?攔截器??rrreee??5、TokenServiceImpl< /code>??rrreee??6、<code style="font-size: 14px;padding: 2px 4px;border-radius: 4px;margin-right: 2px;margin-left: 2px; background-color: rgba(27, 31, 35, 0.05);?? ??: 'Operator Mono', Consolas, Monaco, Menlo, monospace;word-break: break-all;color: rgb(239, 112, 96);">TestApplication ??rrreee??好了，以上便是代碼的實(shí)現(xiàn)分，下面我們就來驗(yàn)證一下。??????????七、測試驗(yàn)證???? ??????獲取??? ?? ??TokenController ：??

   @RestController
   @RequestMapping("/token")
   public class TokenController {
   
       @Autowired
       private TokenService tokenService;
   
       @GetMapping
       public ServerResponse token() {
           return tokenService.createToken();
       }
   
   }

   TestController, 注意@ApiIdempotent注解, 在需要冪等性校驗(yàn)的方法上聲明此注解即可, 不需要校驗(yàn)的無影響：

   @RestController
   @RequestMapping("/test")
   @Slf4j
   public class TestController {
   
       @Autowired
       private TestService testService;
   
       @ApiIdempotent
       @PostMapping("testIdempotence")
       public ServerResponse testIdempotence() {
           return testService.testIdempotence();
       }
   
   }

   獲取token：

   

   查看Redis：

   

   測試接口安全性: 利用Jmeter測試工具模擬50個(gè)并發(fā)請求, 將上一步獲取到的token作為參數(shù)

   

   

   header或參數(shù)均不傳token, 或者token值為空, 或者token值亂填, 均無法通過校驗(yàn), 如token值為abcd。

   

   8. ???? (?? ??)

   

   ? ????? ??? ?? ??? ?? ??? ?? ?? ??? ???? ?? ??? ??? ?? ??? ?? ????. ????, ?? ???? ??? 46?? ??? ???? ?? ?????. ?? ??? ???? ????? ??? ?????. jedisUtil.del(token)? ?? ??? ???? ?? ?? ???? ???? ??? ????. ??? ?? ?? ??? ?? ???? ??? ?? ?????. ???? ??? ???.

   ?? ?? ??:

   

   ?? ??

   

   ??? ?? ?????

   

   ?? ? ??? ?????? ?? ??? ???? ??? ??? ??? ?? ????. ??? ??? ??? ???? ???

   9. ??

   ?? ????? ?? ?????. ?, ? ??? ???? ????? 保證冪等性, 通過攔截器+注解, 就不用每次請求都寫重復(fù)代碼, 其實(shí)也可以利用Spring AOP ?????.

   ?, ??? ??? ???????.