AuthenticationTokenProcessingFilter.java

/*
 *  Copyright 2009-2016 Weibo, Inc.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */

package com.weibo.filter;

import com.weibo.utils.TokenUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.web.authentication.WebAuthenticationDetailsSource;
import org.springframework.stereotype.Component;
import org.springframework.web.filter.GenericFilterBean;

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

@Component
public class AuthenticationTokenProcessingFilter extends GenericFilterBean {

    private final UserDetailsService userDetailsService;

    @Autowired
    public AuthenticationTokenProcessingFilter(UserDetailsService userDetailsService) {
        this.userDetailsService = userDetailsService;
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest httpServletRequest = getAsHttpRequest(request);

        String authToken = extractAuthTokenFromRequest(httpServletRequest);
        String username = TokenUtils.getUserNameFromToken(authToken);

        if (username != null) {
            UserDetails userDetails = userDetailsService.loadUserByUsername(username);
            if (TokenUtils.validateToken(authToken, userDetails)) {
                UsernamePasswordAuthenticationToken authenticationToken = new UsernamePasswordAuthenticationToken(userDetails, null, userDetails.getAuthorities());
                authenticationToken.setDetails(new WebAuthenticationDetailsSource().buildDetails(httpServletRequest));
                SecurityContextHolder.getContext().setAuthentication(authenticationToken);
            }
        }

        chain.doFilter(request, response);
    }

    private HttpServletRequest getAsHttpRequest(ServletRequest request) {
        if (!(request instanceof HttpServletRequest)) {
            throw new RuntimeException("Expecting an HTTP request");
        }

        return (HttpServletRequest) request;
    }

    private String extractAuthTokenFromRequest(HttpServletRequest httpServletRequest) {
        String authToken = httpServletRequest.getHeader("X-Auth-Token");
        if (authToken == null) {
            authToken = httpServletRequest.getParameter("token");
        }
        return authToken;
    }
}