微信OAuth网页认证

    最近要写一个通过微信OAuth协议的网页认证接口，在网上找了一轮，没有找到有什么现成好的代码，就打算自己写算了。

 

首先因为微信的接口都是https的，用HttpClient实现的话因为不清楚是否支持https，所以计划用ajax在客户端完成认证。不过这个绝对是一个十分愚蠢的想法，因为ajax跨域是一个不可逾越的障碍，只不过开始考虑的不周到，直到开始编码的时候才发现，而且还脑袋抽筋的想去解决它，真是耽误不少时间。

 

Ajax行不通以后，逼着使用HttpClient在后台实现了。还是担心HttpClient不支持https，所以在网上看了很久，大部分都是说要导入证书什么的，十分复杂。不过还是迫于无奈，只好找到HttpClient的文档直接就开始实验，发现原来这样访问https HttpClient 是完全支持的，和普通的http没有什么不同，之前的担心多余了，还浪费了好多时间去了解。

 

正式开始，其实微信的认证并不复杂。首先是要调用一个认证URL，引导用户授权(如果有必要)，然后微信会回调指定的回调URL，成功的话返回code 参数，通过code就可以继续获取access_token 和 openid，如果之前用户授权的话，还可以获得用户昵称和地址等一些信息。

 

下面是组装认证URL和处理回调的代码，是从一个HttpServlet和 struts 代码里面直接裁出来的，就是这么个意思而已，编译不过的。

 

第一步，首先要构造一个认证URL，因为这个URL里面包含了回调URL和一个可以带过去的参数，所以一般还是要先自行组装一下。这里面有个地方要注意，state 参数协议里面说是仅支持字母和数字的，所以最好还是用来传一些简单的参数好了，有些人喜欢把一堆参数通过base64加密后放进state 里面传递，但我发现有些情况下还是容易出错，不要冒险的好。

 

	protected void doPost(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		
		StringBuffer sbrCallbackUrl = new StringBuffer();
		StringBuffer sbrWeiXinAuthUrl = new StringBuffer();
		StringBuffer sbrParamer = new StringBuffer();
		boolean boolFastAuth = false;
		
		int nServerPort = 0;
		
		int nPortalPageId = 0;
		String strToUser = request.getParameter("to_user");
		if (null == strToUser || strToUser.trim().length()<=0) {
			log.error("WeixinWebAuth fail,need ToUser");
			return;
		}
		//这个参数是用来指定是否需要引导用户到授权页面
		String strFastAuth = request.getParameter("fast");
		if (null != strFastAuth ) {
			log.info("Fast auth modle");
			boolFastAuth = true;
		}
		
		String strAppId = "appid";//FIXME
		if (null == strAppId || strAppId.trim().length()<=0) {
			log.error("WeixinWebAuth fail,need appid");
			return;
		}
		String strAppSecret = " AppSecret ";//FIXME
		if (null == strAppSecret || strAppSecret.trim().length()<=0) {
			log.error("WeixinWebAuth fail,need AppSecret");
			return;
		}
		
		sbrParamer.append(PARAM); //FIXME
		
		sbrCallbackUrl.append(request.getScheme()+"://");
		sbrCallbackUrl.append(request.getServerName());
		sbrCallbackUrl.append(CALL_BACK_URL);
		
		//组装认证URL
		sbrWeiXinAuthUrl.append(WEIXIN_WEB_AUTH_URL);
		sbrWeiXinAuthUrl.append("?");
		sbrWeiXinAuthUrl.append("appid=" + strAppId);
		sbrWeiXinAuthUrl.append("&");
		sbrWeiXinAuthUrl.append("redirect_uri=" + java.net.URLEncoder.encode(sbrCallbackUrl.toString(),"UTF-8"));
		sbrWeiXinAuthUrl.append("&");
		sbrWeiXinAuthUrl.append("response_type=code");
		sbrWeiXinAuthUrl.append("&");
		if (!boolFastAuth) {
			sbrWeiXinAuthUrl.append("scope=snsapi_userinfo");
		}
		else {
			sbrWeiXinAuthUrl.append("scope=snsapi_base");
		}
		sbrWeiXinAuthUrl.append("&");
		sbrWeiXinAuthUrl.append("state="+sbrParamer);
		sbrWeiXinAuthUrl.append("#wechat_redirect");
		
		log.info("Goto weixin auth path:" + sbrWeiXinAuthUrl);
		response.sendRedirect(sbrWeiXinAuthUrl.toString());
	}

 

      组装完地址，直接重定向过去。

 

第二步，就是要处理回调过来的信息。这个其实也比较简单。

 

import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import net.sf.json.JSONObject;

import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;

public class WeixinWebAuthCallbackAction extends Action {
	private final String strAccessTokenUrl = "https://api.weixin.qq.com/sns/oauth2/access_token";
	private final String strGetUserInfoUrl = "https://api.weixin.qq.com/sns/userinfo";
	
    @Override
    protected ActionForward executeAction(ActionMapping mapping,
            ActionForm actionForm, HttpServletRequest request,
            HttpServletResponse response) throws Exception {

    	response.setContentType("text/html");
    	response.setCharacterEncoding("UTF-8");
    	
    	String strWeixinCallbackCode = null;
    	String strParamers = null;
    	
        log.info("微信web认证获取帐号开始");

        strWeixinCallbackCode = request.getParameter("code");
        log.info("return code:" + strWeixinCallbackCode);
        strParamers = request.getParameter("state");
        log.info("return :" + strParamers);

        if (null == strWeixinCallbackCode || strWeixinCallbackCode.equals("authdeny") 
        		|| null == strParamers || strParamers.isEmpty()) {
            log.info("用户拒绝授权");
            request.setAttribute("errcode", 1);
            request.setAttribute("errmsg", "用户拒绝授权");				
            return mapping.findForward("fail");
        }
        
        String strAccessToken = null;
        String strUserOpenId = null;

		String strNickName = "";
		String strSex = "";//1 man;2 female;3 unknown;
        String address = "";

        String strAppId = "AppId";//FIXME
        String strAppSecret = "AppSecret";//FIXME
		
        Map<String, String> mapAccessToken = getAccessTokenAndUid(strWeixinCallbackCode, strAppId, strAppSecret);
        if (null == mapAccessToken || null != mapAccessToken.get("errcode")) {
            log.info("获取访问token错误");
            if (null != mapAccessToken) {
	            request.setAttribute("errcode", mapAccessToken.get("errcode"));
	            request.setAttribute("errmsg", mapAccessToken.get("errmsg"));				
			}
            return mapping.findForward("fail");
        }
        strAccessToken = mapAccessToken.get("access_token");
        strUserOpenId = mapAccessToken.get("openid");
        Map<String, String> mapUserInfo = getUserInfo(strAccessToken, strUserOpenId);        
		if (null != mapUserInfo) {
	        if(null != mapUserInfo.get("errcode")){
	            log.info("获取用户信息错误");
	            request.setAttribute("errcode", mapUserInfo.get("errcode"));
	            request.setAttribute("errmsg", mapUserInfo.get("errmsg"));
		        return mapping.findForward("fail");
	        }
	        strNickName = mapUserInfo.get("nickname");
	        strSex = mapUserInfo.get("sex");
		}
               
        log.info("weixin web auth,user:"+strNickName+" sex:"+strSex);
        
        return mapping.findForward("success");
        
    }
    
    private Map<String , String> getAccessTokenAndUid(String strCode,String strAppId,String strAppSecret){
        String responseDate = "" ;
        Map<String , String> token = null;

        PostMethod postMethod = new PostMethod(strAccessTokenUrl);
        postMethod.addParameter("appid", strAppId);
        postMethod.addParameter("secret",strAppSecret);
        postMethod.addParameter("code",strCode);
        postMethod.addParameter("grant_type","authorization_code");
        
        HttpClient client = new HttpClient();
        try {
            client.executeMethod(postMethod);
            responseDate = postMethod.getResponseBodyAsString();
        } catch (Exception e) {
        	log.error(e.getMessage());
            e.printStackTrace();
        }
        
        if(responseDate.trim().length()>0){
            token = new HashMap<String, String>();
            JSONObject jsonData = JSONObject.fromObject(responseDate);
            if (jsonData.has("errcode")) {
				log.error("Get access token fail,reason:" + jsonData.getString("errmsg"));
				token.put("errcode", jsonData.getString("errcode"));
				token.put("errmsg", jsonData.getString("errmsg"));
				return null;
			}
            
            log.info("Get access_token:"+jsonData.getString("access_token")+";openid:"+jsonData.getString("openid"));
            token.put("access_token", jsonData.getString("access_token"));
            token.put("openid", jsonData.getString("openid"));
        }
        return  token;
    }
    
    
    private Map<String , String> getUserInfo(String strAccessToken,String strOpenId){
        String responseDate = "" ;
        Map<String , String> token = null;

        PostMethod postMethod = new PostMethod(strGetUserInfoUrl);
        postMethod.addParameter("access_token", strAccessToken);
        postMethod.addParameter("openid",strOpenId);
        postMethod.addParameter("lang","zh_CN");
        
        HttpClient client = new HttpClient();
        try {
            client.executeMethod(postMethod);
            responseDate = postMethod.getResponseBodyAsString();
        } catch (Exception e) {
        	log.error(e.getMessage());
            e.printStackTrace();
        }
        if(responseDate.trim().length()>0){
            token = new HashMap<String, String>();
            JSONObject jsonData = JSONObject.fromObject(responseDate);
            if (jsonData.has("errcode")) {
				log.info("Get user info fail,reason:["+jsonData.getString("errcode")+ "]" + jsonData.getString("errmsg"));
			//这个是没用户授权，不能取用户信息的返回错误码，文档没提及，随时可能变的
            	if (48001 == jsonData.getLong("errcode")) {
            		log.info("Can't get userinfo,but wo can continue.");
					return null;
				}
				token.put("errcode", jsonData.getString("errcode"));
				token.put("errmsg", jsonData.getString("errmsg"));
				return token;
			}
            
            if (!jsonData.has("openid") || !jsonData.has("nickname")) {
            	log.info("No user info available");
				return null;
			}
            log.info("weixin web auth,user:"+jsonData.getString("nickname")+" sex:"+jsonData.getString("sex")
            		+ " province:"+jsonData.getString("province")+" city:"+jsonData.getString("city")
            		+ " country:"+jsonData.getString("country"));
            
            token.put("openid", jsonData.getString("openid"));
            token.put("nickname", jsonData.getString("nickname"));
            token.put("sex", jsonData.getString("sex"));
            token.put("province", jsonData.getString("province"));
            token.put("city", jsonData.getString("city"));
            token.put("country", jsonData.getString("country"));
        }
        return  token;
    }
}

 

 

 

 

 

评论

2 楼 victorpeng 2015-11-30  

楼主能给个demo吗？谢谢...

1 楼 jhp1900 2015-05-13  

博主好，能给个原代码吗？
正在做这个，也是资料找的焦头烂额！
邮箱：[e-mail]
谢谢博主了！