微信登录

ゞ浴缸里的玫瑰 2023-03-04 06:34 11阅读 0赞

一，流程：

1，用户请求微信登录

2，第三方应用请求微信开放平台，获取code，传参中就有回调url

3，用户确认登录第三方应用，微信开放平台回调第三方应用的一个url，带上code

4，第三方应用拿到code，再带上appid，appsecrect等参数，继续请求微信开放平台，获取access\_token（授权票据）

5，微信开放平台会将access\_token返回给第三方应用

6，第三方应用拿到access\_token，获取用户信息

二，接入条件

1，注册开发者账号

进入 微信开放平台 页面申请账号

2，拥有一个已审核通过的网站应用

进入 微信开放平台--网站应用开发--创建应用，后会获取appid，secret参数

三，代码实现

//公共项目，创建工具类，用于访问URL，对返回值做封装
    package cn.bdqn.common;
    
    public class UrlUtils{
        public static String loadURL(String urlStr){
            try{
                URL url = new URL(urlStr);
                HttpUrlConnection urlConnection = (HttpUrlConnection)url.openConnection();
                urlConnection.setRequestMethod("GET");
                urlConnection.connect();
                InputStream inputStream = urlConnection.getInputStream();
                String responseStr = ConvertToString(inputStream);
                return responseStr;
            }catch(IOException e){
                e.printStackTrace();
                return null;
            }
        }
        
        //把流转化为String
        public static String ConvertToString(InputStream inputStream){
            InputStreamReader isr = new InputStreamReader(inputStream);
            BufferedReader br = new BufferedReader(isr);
            StringBuilder result = new StringBuilder();
            String line = null;
            try{
                while((line = br.readLine()) != null){
                    result.append(line = "\n");
                }
            }catch(IOException e){
                e.printStackTrace();
            }finally{
                try{
                    isr.close();
                    inputStream.close();
                    br.close();
                }catch(IOException e){
                    e.sprintStackThace();
                }
            }
        }
    }
    ····················································································
    //消费者项目
    //创建配置类
    package cn.bdqn.config;
    
    @Component
    @ConfigurationProperties(prefix = "wechat")  // 给属性注入配置文件里的值
    public class WechatConfig {
        
        private String appId; //在微信开放平台创建应用后会获得appId，appSecret，在配置文件中获取 
    
        private String appSecret;
    
        //回调Url，要能外网访问（花生壳转件可以做内网穿透），使用urlEncode对链接编码
        private String redirectUrl; 
    
    
        //生成get/set方法略
    
    }
    
    ·············································································
    //消费者controller
    
    package cn.bdqn.controller;
    
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    import cn.bdqn.common.Dto;
    
    /**
     *微信登录
     */
    @Controller
    @RequestMapping(value = "/vendors")
    public class VendorController {
        @Resource
        private WechatConfig wechatConfig; 
    
        @Resource
        private QgLoginService qgLoginService; //消费者业务层接口，对登录的业务操作
        
        /**
         *微信登录第一步：请求获取code
         *@param response
         *@return
         */
        @RequestMapping(value = "/wechat/login")
        public void veChatLogin(HttpServletResponse response){       
            StringBuilder sb = new StringBuilder("");
            sb.append("https://open.weixin.qq.com/connect/qrconnect?");
            sb.append("appid=");
            sb.append(wechatConfig.getAppid());
            sb.append("&redirect_uri=");
            sb.append(wechatConfig.getRedirectUrl());
            sb.append("&response_type=code");
            sb.append("&scope=snsapi_login&state=STATE#wechat_redirect");
    
            //重定向
            try{
                response.sendRedirect(sb.toString());
            }catch(IOException e){
                e.pringStackTrace();
            }     
        }
        
        /**
         *微信登录第二，三步：通过code获取access_token，通过access_token获取用户信息并登录首页
         *执行了第一步方法后，会通过回调URL调用此方法
         *@param code
         *@param response
         *@param request
         *@return
         */
        @RequestMapping(value = "/wechat/callback")
        public void veChatCallBack(@RequestParam String code,HttpServletResponse response,
            HttpServletRequest request){
            //  对回调URL“http://localhost:8082/vendors/wechat/callback"进行外网穿透和编码
            // “http://localhost:8082” 可以用花生壳软件内网穿透
            // “穿透路径/vendors/wechat/callback” 用urlEncode在线编码后获得回调URL，
                也是wechatConfig.getRedirectUrl()的值
            
            //第二步
            StringBuilder accesstokenUrl = new StringBuilder("");
            sb.append("https://api.weixin.qq.com/sns/oauth2/access_token?");
            sb.append("appid=");
            sb.append(wechatConfig.getAppid());
            sb.append("&secret=");
            sb.append(wechatConfig.getAppSecret());
            sb.append("&code="+code);
            sb.append("&grant_type=authorization_code");
            
            //调用URL请求工具类，把返回流转为String
            String accesstoken = UrlUtils.loadUrl(accesstokenUrl.toString());
            
            //转为MAP
            Map<String,Object> accesstokenMap = JSON.parseObject(accesstoken,Map.class);
            
            //第三步    
            StringBuilder userinfoUrl = new StringBuilder("");
            sb.append("https://api.weixin.qq.com//sns/userinfo?");
            sb.append("access_token="+accesstokenMap.get("access_token").toString());
            sb.append("&apenid="+accesstokenMap.get("openid").toString());
            
            String userinfo = UrlUtils.loadUrl(userinfoUrl.toString());
            Map<String,Object> userinfoMap = JSON.parseObject(userinfo,Map.class);
            
            //拿到用户信息，然后做业务操作        
    
            //跳转到首页
            //注意，首页的 穿透路径 需要在微信开放平台创建应用时在授权回调域里需要配置，不然不会访问
            StringBuilder indexUrl = new StringBuilder("");
            sb.append("http://路径+端口的穿透路径/index.xml");
            try{
                response.sendRedirect(indexUrl.toString());
            }catch(IOException e){
                e.pringStackTrace();
            }
        }
    }