Spring boot通过AOP防止API重复请求代码实例

 @Target(ElementType.METHOD)
 @Retention(RetentionPolicy.RUNTIME)
 public @interface NoRepeatSubmission {
 
 }

import com.gotrade.apirepeatrequest.annotation.NoRepeatSubmission;
import com.gotrade.apirepeatrequest.common.JacksonSerializer;
import com.gotrade.apirepeatrequest.model.Result;
import lombok.extern.slf4j.Slf4j;
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.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.ValueOperations;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Objects;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;



@Slf4j
@Aspect
@Component
public class NoRepeatSubmissionAspect {

  @Autowired
  RedisTemplate<String, String> redisTemplate;

  /**
   * 环绕通知
   * @param pjp
   * @param ars
   * @return
   */
  @Around("execution(public * com.gotrade.apirepeatrequest.controller..*.*(..)) && @annotation(ars)")
  public Object doAround(ProceedingJoinPoint pjp, NoRepeatSubmission ars) {
    ValueOperations<String, String> opsForValue = redisTemplate.opsForValue();
    try {
      if (ars == null) {
        return pjp.proceed();
      }

      HttpServletRequest request = ((ServletRequestAttributes) Objects.requireNonNull(RequestContextHolder.getRequestAttributes())).getRequest();

      String token = request.getHeader("Token");
      if (!checkToken(token)) {
        return Result.failure("Token无效");
      }
      String servletPath = request.getServletPath();
      String jsonString = this.getRequestParasJSONString(pjp);
      String sha1 = this.generateSHA1(jsonString);

      // key = token + servlet path
      String key = token + "-" + servletPath + "-" + sha1;

      log.info("\n{\n\tServlet Path: {}\n\tToken: {}\n\tJson String: {}\n\tSHA-1: {}\n\tResult Key: {} \n}", servletPath, token, jsonString, sha1, key);

      // 如果Redis中有这个key, 则url视为重复请求
      if (opsForValue.get(key) == null) {
        Object o = pjp.proceed();
        opsForValue.set(key, String.valueOf(0), 3, TimeUnit.SECONDS);
        return o;
      } else {
        return Result.failure("请勿重复请求");
      }
    } catch (Throwable e) {
      e.printStackTrace();
      return Result.failure("验证重复请求时出现未知异常");
    }
  }

  /**
   * 获取请求参数
   * @param pjp
   * @return
   */
  private String getRequestParasJSONString(ProceedingJoinPoint pjp) {
    String[] parameterNames = ((MethodSignature) pjp.getSignature()).getParameterNames();
    ConcurrentHashMap<String, String> args = null;

    if (Objects.nonNull(parameterNames)) {
      args = new ConcurrentHashMap<>(parameterNames.length);
      for (int i = 0; i < parameterNames.length; i++) {
        String value = pjp.getArgs()[i] != null ? pjp.getArgs()[i].toString() : "null";
        args.put(parameterNames[i], value);
      }
    }
    return JacksonSerializer.toJSONString(args);
  }

  private boolean checkToken(String token) {
    if (token == null || token.isEmpty()) {
      return false;
    }
    return true;
  }

  private String generateSHA1(String str){
    if (null == str || 0 == str.length()){
      return null;
    }
    char[] hexDigits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
        'a', 'b', 'c', 'd', 'e', 'f'};
    try {
      MessageDigest mdTemp = MessageDigest.getInstance("SHA1");
      mdTemp.update(str.getBytes(StandardCharsets.UTF_8));

      byte[] md = mdTemp.digest();
      int j = md.length;
      char[] buf = new char[j * 2];
      int k = 0;
      for (int i = 0; i < j; i++) {
        byte byte0 = md[i];
        buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
        buf[k++] = hexDigits[byte0 & 0xf];
      }
      return new String(buf);
    } catch (NoSuchAlgorithmException e) {
      e.printStackTrace();
    }
    return null;
  }
}