springsecurity-微服务-springsecurity授权过滤器

当用户登录后再次访问时，我们需要拿到用户的token，去查redis的用户权限，并赋予用户权限。差不多就这个过程，但很多步骤，springsecurity都封装好了，下面写一个授权过滤器，主要重写一个方法doFilterInternal，该方法的目的的话就是获取redis中用户的权限列表，并设置到一个类里面，方便下一个过滤器来使用。

public class TokenAuthenticationFilter extends BasicAuthenticationFilter {
    private TokenManager tokenManager;
    private RedisTemplate redisTemplate;

    public TokenAuthenticationFilter(AuthenticationManager authManager, TokenManager tokenManager,RedisTemplate redisTemplate) {
        super(authManager);
        this.tokenManager = tokenManager;
        this.redisTemplate = redisTemplate;
    }

    @Override
    protected void doFilterInternal(HttpServletRequest req, HttpServletResponse res, FilterChain chain)
            throws IOException, ServletException {
        logger.info("================="+req.getRequestURI());
        if(req.getRequestURI().indexOf("admin") == -1) {
            chain.doFilter(req, res);
            return;
        }

        UsernamePasswordAuthenticationToken authentication = null;
        try {
            authentication = getAuthentication(req);
        } catch (Exception e) {
            ResponseUtil.out(res, R.error());
        }

        if (authentication != null) {
            SecurityContextHolder.getContext().setAuthentication(authentication);
        } else {
            ResponseUtil.out(res, R.error());
        }
        chain.doFilter(req, res);
    }

    private UsernamePasswordAuthenticationToken getAuthentication(HttpServletRequest request) {
        // token置于header里
        String token = request.getHeader("token");
        if (token != null && !"".equals(token.trim())) {
            String userName = tokenManager.getUserFromToken(token);

            List<String> permissionValueList = (List<String>) redisTemplate.opsForValue().get(userName);
            Collection<GrantedAuthority> authorities = new ArrayList<>();
            for(String permissionValue : permissionValueList) {
                if(StringUtils.isEmpty(permissionValue)) continue;
                SimpleGrantedAuthority authority = new SimpleGrantedAuthority(permissionValue);
                authorities.add(authority);
            }

            if (!StringUtils.isEmpty(userName)) {
                return new UsernamePasswordAuthenticationToken(userName, token, authorities);
            }
            return null;
        }
        return null;
    }
}