content: package com.genshin.ojrun.filter;
  
  
  import com.genshin.ojcommon.domain.entity.LoginUser;
  import com.genshin.ojcommon.utils.JwtUtil;
  import com.genshin.ojcommon.utils.RedisCache;
  import io.jsonwebtoken.Claims;
  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;
  import java.util.Objects;
  
  @Component
  public class JwtAuthenticationTokenFilter extends OncePerRequestFilter {
  
      @Autowired
      private RedisCache redisCache;
  
      protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
          //获取token
          String token = request.getHeader("token");
          if (!StringUtils.hasText(token)) {
              //放行, 没有token就让后面去放行
              filterChain.doFilter(request, response);
              return;
          }
          //解析token
          String userid;
          try {
              Claims claims = JwtUtil.parseJWT(token);
              userid = claims.getSubject();
          } catch (Exception e) {
              e.printStackTrace();
              throw new RuntimeException("token非法");
          }
          //从redis中获取用户信息
          String redisKey = "login: " + userid;
          LoginUser loginUser = redisCache.getCacheObject(redisKey);
          if(Objects.isNull(loginUser)){
              throw new RuntimeException("用户未登录");
          }
          //存入SecurityContextHolder， 需要使用 将LoginUser 改成 UsernamePasswordAuthenticationToken
          //TODO 获取权限信息封装到Authentication中
          // 从这里传入权限信息
  
          UsernamePasswordAuthenticationToken authenticationToken =
                  new UsernamePasswordAuthenticationToken(loginUser,null,loginUser.getAuthorities());
          SecurityContextHolder.getContext().setAuthentication(authenticationToken);
          //放行
          filterChain.doFilter(request, response);
      }
  }
  