Spring Boot 使用 AOP來防止重覆提交

思路

1. 自定義註解 @NoRepeatSubmit 標記所有Controller中的提交請求

2. 通過AOP 對所有標記了 @NoRepeatSubmit 的方法攔截

3. 在業務方法執行前，獲取當前用戶的 token（或者JSessionId）+ 當前請求地址，作為一個唯一 KEY，去獲取 Redis 分散式鎖（如果此時併發獲取，只有一個線程會成功獲取鎖）

4. 業務方法執行後，釋放鎖

關於Redis 分散式鎖

• 不瞭解的同學戳這裡 ==> Redis分散式鎖的正確實現方式

• 使用Redis 是為了在負載均衡部署，如果是單機的部署的項目可以使用一個線程安全的本地Cache 替代 Redis

Code

這裡只貼出 AOP 類和測試類，完整代碼見 ==> Gitee

 @Aspect
 @Component
 public class RepeatSubmitAspect {
 ​
     private final static Logger LOGGER = LoggerFactory.getLogger(RepeatSubmitAspect.class);
 ​
     @Autowired
     private RedisLock redisLock;
 ​
     @Pointcut("@annotation(noRepeatSubmit)")
     public void pointCut(NoRepeatSubmit noRepeatSubmit) {
     }
 ​
     @Around("pointCut(noRepeatSubmit)")
     public Object around(ProceedingJoinPoint pjp, NoRepeatSubmit noRepeatSubmit) throws Throwable {
         int lockSeconds = noRepeatSubmit.lockTime();
 ​
         HttpServletRequest request = RequestUtils.getRequest();
         Assert.notNull(request, "request can not null");
 ​
         // 此處可以用token或者JSessionId
         String token = request.getHeader("Authorization");
         String path = request.getServletPath();
         String key = getKey(token, path);
         String clientId = getClientId();
 ​
         boolean isSuccess = redisLock.tryLock(key, clientId, lockSeconds);
 ​
         if (isSuccess) {
             LOGGER.info("tryLock success, key = [{}], clientId = [{}]", key, clientId);
             // 獲取鎖成功, 執行進程
             Object result;
             try {
                 result = pjp.proceed();
 ​
             } finally {
                 // 解鎖
                 redisLock.releaseLock(key, clientId);
                 LOGGER.info("releaseLock success, key = [{}], clientId = [{}]", key, clientId);
 ​
             }
 ​
             return result;
 ​
         } else {
             // 獲取鎖失敗，認為是重覆提交的請求
             LOGGER.info("tryLock fail, key = [{}]", key);
             return new ResultBean(ResultBean.FAIL, "重覆請求，請稍後再試", null);
         }
 ​
     }
 ​
     private String getKey(String token, String path) {
         return token + path;
     }
 ​
     private String getClientId() {
         return UUID.randomUUID().toString();
     }
 ​
 }

多線程測試

測試代碼如下，模擬十個請求併發同時提交

 @Component
 public class RunTest implements ApplicationRunner {
 ​
     private static final Logger LOGGER = LoggerFactory.getLogger(RunTest.class);
 ​
     @Autowired
     private RestTemplate restTemplate;
 ​
     @Override
     public void run(ApplicationArguments args) throws Exception {
         System.out.println("執行多線程測試");
         String url="http://localhost:8000/submit";
         CountDownLatch countDownLatch = new CountDownLatch(1);
         ExecutorService executorService = Executors.newFixedThreadPool(10);
 ​
         for(int i=0; i<10; i++){
             String userId = "userId" + i;
             HttpEntity request = buildRequest(userId);
             executorService.submit(() -> {
                 try {
                     countDownLatch.await();
                     System.out.println("Thread:"+Thread.currentThread().getName()+", time:"+System.currentTimeMillis());
                     ResponseEntity<String> response = restTemplate.postForEntity(url, request, String.class);
                     System.out.println("Thread:"+Thread.currentThread().getName() + "," + response.getBody());
 ​
                 } catch (InterruptedException e) {
                     e.printStackTrace();
                 }
             });
         }
 ​
         countDownLatch.countDown();
     }
 ​
     private HttpEntity buildRequest(String userId) {
         HttpHeaders headers = new HttpHeaders();
         headers.setContentType(MediaType.APPLICATION_JSON);
         headers.set("Authorization", "yourToken");
         Map<String, Object> div = new HashMap<>();
         div.put("userId", userId);
         return new HttpEntity<>(div, headers);
     }
 ​
 }

成功防止重覆提交，控制台日誌如下，可以看到十個線程的啟動時間幾乎同時發起，只有一個請求提交成功了

結論

大家有什麼要說的，歡迎在評論區留言

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