JdcProject/src/main/java/com/jdc/jdcproject/controller/WxApiController.java

package com.jdc.jdcproject.controller;

import com.google.gson.Gson;
import com.jdc.jdcproject.entity.Users;
import com.jdc.jdcproject.exceptionhandler.JdcException;
import com.jdc.jdcproject.service.IUsersService;
import com.jdc.jdcproject.utils.ConstantUtils;
import com.jdc.jdcproject.utils.HttpUtils;
import com.jdc.jdcproject.utils.JwtUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpSession;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.HashMap;

@Controller
@RequestMapping("/api/ucenter/wx")
@CrossOrigin
public class WxApiController {

    @Autowired
    private IUsersService usersService;

    @GetMapping("login")
    public String genQrConnect(HttpSession session) {
        // 微信开放平台授权baseUrl
        String baseUrl = "https://open.weixin.qq.com/connect/qrconnect" +
                "?appid=%s" +
                "&redirect_uri=%s" +
                "&response_type=code" +
                "&scope=snsapi_login" +
                "&state=%s" +
                "#wechat_redirect";
        // 回调地址
        String redirectUrl = ConstantUtils.WX_OPEN_REDIRECT_URL; //获取业务服务器重定向地址
        try {
            redirectUrl = URLEncoder.encode(redirectUrl, "UTF-8"); //url编码
        } catch (UnsupportedEncodingException e) {
            throw new JdcException(20001, e.getMessage());
        }

        // 防止csrf攻击（跨站请求伪造攻击）
        //String state = UUID.randomUUID().toString().replaceAll("-", "");//一般情况下会使用一个随机数
        String state = "imhelen";//为了让大家能够使用我搭建的外网的微信回调跳转服务器，这里填写你在ngrok的前置域名
        System.out.println("state = " + state);

        // 采用redis等进行缓存state 使用sessionId为key 30分钟后过期，可配置
        //键："wechar-open-state-" + httpServletRequest.getSession().getId()
        //值：satte
        //过期时间：30分钟

        //生成qrcodeUrl
        String qrcodeUrl = String.format(
                baseUrl,
                ConstantUtils.WX_OPEN_APP_ID,
                redirectUrl,
                state);


        return "redirect:" + qrcodeUrl;
    }

    @GetMapping("callback")
    public String callback(String code, String state, HttpSession session) {
        try {
            //得到授权临时票据code
            System.out.println("code = " + code);
            System.out.println("state = " + state);

            //向认证服务器发送请求换取access_token
            String baseAccessTokenUrl = "https://api.weixin.qq.com/sns/oauth2/access_token" +
                    "?appid=%s" +
                    "&secret=%s" +
                    "&code=%s" +
                    "&grant_type=authorization_code";

            String accessTokenUrl = String.format(baseAccessTokenUrl,
                    ConstantUtils.WX_OPEN_APP_ID,
                    ConstantUtils.WX_OPEN_APP_SECRET,
                    code);
            String result = HttpUtils.get(accessTokenUrl);
            System.out.println("accessToken=============" + result);

            //解析json字符串
            Gson gson = new Gson();
            HashMap map = gson.fromJson(result, HashMap.class);
            String accessToken = (String) map.get("access_token");
            String openid = (String) map.get("openid");

            //查询数据库当前用用户是否曾经使用过微信登录
          /*  Users member = usersService.getByOpenid(openid);
            if (member == null) {
                System.out.println("新用户注册");
                //访问微信的资源服务器，获取用户信息
                String baseUserInfoUrl = "https://api.weixin.qq.com/sns/userinfo" +
                        "?access_token=%s" +
                        "&openid=%s";
                String userInfoUrl = String.format(baseUserInfoUrl, accessToken, openid);
                String resultUserInfo = null;
                resultUserInfo = HttpUtils.get(userInfoUrl);
                System.out.println("resultUserInfo==========" + resultUserInfo);
                HashMap<String, Object> mapUserInfo = gson.fromJson(resultUserInfo, HashMap.class);
                String nickname = (String) mapUserInfo.get("nickname");
                String headimgurl = (String) mapUserInfo.get("headimgurl");

            }*/
            //String memberIdByJwtToken = JwtUtils.getJwtToken(member.getId(), member.getUsername());
            return "redirect:http://localhost:8000?token=" ;
        } catch (Exception e) {
            throw new JdcException(20001, "登陆失败");
        }
    }

}