JwtAuthenticationTokenFilter

package com.oep.backend.config.filter;

//  实现config.filter.JwtAuthenticationTokenFilter类，用来验证jwt token，如果验证成功，则将User信息注入上下文中

import com.oep.backend.mapper.AccountMapper;
import com.oep.backend.pojo.Account;
import com.oep.backend.serviceImpl.utils.UserDetailsImpl;
import com.oep.backend.utils.JwtUtil;
import io.jsonwebtoken.Claims;
import org.jetbrains.annotations.NotNull;  //  没有这个包的话要自己去导入
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.filter.OncePerRequestFilter;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@Component
public class JwtAuthenticationTokenFilter extends OncePerRequestFilter {
    @Autowired
    private AccountMapper userMapper;

    @Override
    protected void doFilterInternal(HttpServletRequest request, @NotNull HttpServletResponse response, @NotNull FilterChain filterChain) throws ServletException, IOException {
        String token = request.getHeader("Authorization");

        if (!StringUtils.hasText(token) || !token.startsWith("Bearer ")) {
            filterChain.doFilter(request, response);
            return;
        }

        token = token.substring(7);

        String userid;
        try {
            Claims claims = JwtUtil.parseJWT(token);
            userid = claims.getSubject();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }

        Account account = userMapper.selectById(Integer.parseInt(userid));

        if (account == null) {
            throw new RuntimeException("用户名未登录");
        }

        UserDetailsImpl loginUser = new UserDetailsImpl(account);
        UsernamePasswordAuthenticationToken authenticationToken =
                new UsernamePasswordAuthenticationToken(loginUser, null, null);

        SecurityContextHolder.getContext().setAuthentication(authenticationToken);

        filterChain.doFilter(request, response);
    }
}