您好,登錄后才能下訂單哦!
在傳統的web項目中,防止重復提交,通常做法是:后端生成一個唯一的提交令牌(uuid),并存儲在服務端。頁面提交請求攜帶這個提交令牌,后端驗證并在第一次驗證后刪除該令牌,保證提交請求的唯一性。
上述的思路其實沒有問題的,但是需要前后端都稍加改動,如果在業務開發完在加這個的話,改動量未免有些大了,本節的實現方案無需前端配合,純后端處理。
思路
關于Redis 分布式鎖
不了解的同學戳這里 ==> Redis分布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
這里只貼出 AOP 類和測試類,完整代碼見 ==> Gitee
@Aspect @Component public class RepeatSubmitAspect { private static final Logger LOGGER = LoggerFactory.getLogger(RepeatSubmitAspect.class); @Autowired private RedisLock redisLock; @Pointcut("@annotation(com.gitee.taven.aop.NoRepeatSubmit)") public void pointCut() {} @Around("pointCut()") public Object before(ProceedingJoinPoint pjp) { try { 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, 10); LOGGER.info("tryLock key = [{}], clientId = [{}]", key, clientId); if (isSuccess) { LOGGER.info("tryLock success, key = [{}], clientId = [{}]", key, clientId); // 獲取鎖成功, 執行進程 Object result = pjp.proceed(); // 解鎖 redisLock.releaseLock(key, clientId); LOGGER.info("releaseLock success, key = [{}], clientId = [{}]", key, clientId); return result; } else { // 獲取鎖失敗,認為是重復提交的請求 LOGGER.info("tryLock fail, key = [{}]", key); return new ApiResult(200, "重復請求,請稍后再試", null); } } catch (Throwable throwable) { throwable.printStackTrace(); } return new ApiResult(500, "系統異常", 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,模擬十個請求并發同時提交
@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> body = new HashMap<>(); body.put("userId", userId); return new HttpEntity<>(body, headers); } }
成功防止重復提交,控制臺日志如下,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
本節demo
戳這里 ==> Gitee
build項目之后,啟動本地redis,運行項目自動執行測試方法
以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支持億速云。
免責聲明:本站發布的內容(圖片、視頻和文字)以原創、轉載和分享為主,文章觀點不代表本網站立場,如果涉及侵權請聯系站長郵箱:is@yisu.com進行舉報,并提供相關證據,一經查實,將立刻刪除涉嫌侵權內容。