backend/src/main/java/nju/seec/helper/aspect/auth/AuthAspect.java

package nju.seec.helper.aspect.auth;

import nju.seec.helper.util.Consts;
import nju.seec.helper.dto.LoginUser;
import nju.seec.helper.util.exception.HelperException;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.springframework.beans.BeanUtils;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpSession;
import java.util.Arrays;
import java.util.Objects;
import java.util.stream.Collectors;

/**
 * @author cst
 */
@Aspect
@Component
public class AuthAspect {
    @Before("execution(public * nju.seec.helper.controller.*.*(..)) && @annotation(auth)")
    public void authCheck(JoinPoint joinPoint, Auth auth) {
        HttpSession session =
                ((ServletRequestAttributes) Objects.requireNonNull(RequestContextHolder.getRequestAttributes()))
                        .getRequest()
                        .getSession();

        LoginUser user = (LoginUser) session.getAttribute(Consts.SESSION_USER_NAME);
        if (user == null) {
            throw HelperException.of(HelperException.ExceptionType.NOT_LOGIN, "您未登录");
        } else if (!Arrays
                .stream(auth.roles())
                .collect(Collectors.toSet())
                .contains(user.getType())) {
            throw HelperException.of(HelperException.ExceptionType.FORBIDDEN, String.format("您暂时无法%s，请重新登录", auth.message()));
        }

        Object[] objects = joinPoint.getArgs();
        for (Object o : objects) {
            if (o.getClass() == LoginUser.class) {
                BeanUtils.copyProperties(user, o);
                break;
            }
        }
    }
}