1、微信扫码登录-生成二维码

微信官方开放文档：https://developers./doc/oplatform/Website_App/WeChat_Login/Wechat_Login.html

生成微信二维码：直接请求微信提供固定的地址，向地址后面拼接参数

Controller:

package com.atguigu.ucenter.controller;import com.atguigu.ucenter.utils.ConstantWxUtils;import io.swagger.annotations.Api;import io.swagger.annotations.ApiOperation;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 java.io.UnsupportedEncodingException;import .URLEncoder;/*** @Author panghl* @Date /2/6 21:27* @Description TODO**/@CrossOrigin//注意这里没有配置 @RestController@Controller@RequestMapping("/api/ucenter/wx/")@Api(tags = {"微信接口"})public class WxApiController {@ApiOperation(value = "生成微信二维码")@GetMapping("login")public String getWxCode() {// String url= "https://open./connect/qrconnect" +//"?appid="+ ConstantWxUtils.WX_OPEN_APP_ID+"&response_type=code";//微信开放平台授权baseUrl %s相当于?代表占位符String baseUrl = "https://open./connect/qrconnect" +"?appid=%s" +"&redirect_uri=%s" +"&response_type=code" +"&scope=snsapi_login" +"&state=%s" +"#wechat_redirect";//对redirect_url 进行URLEncoder编码String redirect_url= ConstantWxUtils.WX_OPEN_REDIRECT_URL;try {redirect_url = URLEncoder.encode(redirect_url, "UTF-8");} catch (Exception e) {e.printStackTrace();}// 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//给baseUrl %s 里面 设置值String url = String.format(baseUrl,ConstantWxUtils.WX_OPEN_APP_ID,ConstantWxUtils.WX_OPEN_REDIRECT_URL,"atguigu");//重定向到请求微信地址里面请求微信地址return "redirect:"+url;}@ApiOperation(value = "获取扫描人信息，添加数据")@GetMapping("callback")public String callback(String code,String state){return "redirect:http://localhost:3000?code="+code+"&state="+state;}}

2、微信扫描登录-获取扫码人信息

package com.atguigu.ucenter.controller;import mon.R;import mon.jwt.JwtUtils;import com.atguigu.servicebase.exceptionhandler.ELeanExeception;import com.atguigu.ucenter.entity.Member;import com.atguigu.ucenter.service.MemberService;import com.atguigu.ucenter.utils.ConstantWxUtils;import com.atguigu.ucenter.utils.HttpClientUtils;import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;import com.google.gson.Gson;import io.swagger.annotations.Api;import io.swagger.annotations.ApiOperation;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 .URLEncoder;import java.util.HashMap;import java.util.Map;/*** @Author panghl* @Date /2/6 21:27* @Description TODO**/@CrossOrigin//注意这里没有配置 @RestController@Controller@RequestMapping("/api/ucenter/wx/")@Api(tags = {"微信接口"})public class WxApiController {@Autowiredprivate MemberService memberService;@ApiOperation(value = "生成微信二维码")@GetMapping("login")public String getWxCode() {// String url= "https://open./connect/qrconnect" +//"?appid="+ ConstantWxUtils.WX_OPEN_APP_ID+"&response_type=code";//微信开放平台授权baseUrl %s相当于?代表占位符String baseUrl = "https://open./connect/qrconnect" +"?appid=%s" +"&redirect_uri=%s" +"&response_type=code" +"&scope=snsapi_login" +"&state=%s" +"#wechat_redirect";//对redirect_url 进行URLEncoder编码String redirect_url = ConstantWxUtils.WX_OPEN_REDIRECT_URL;try {redirect_url = URLEncoder.encode(redirect_url, "UTF-8");} catch (Exception e) {e.printStackTrace();}// 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//给baseUrl %s 里面 设置值String url = String.format(baseUrl,ConstantWxUtils.WX_OPEN_APP_ID,ConstantWxUtils.WX_OPEN_REDIRECT_URL,"atguigu");//重定向到请求微信地址里面请求微信地址return "redirect:" + url;}@ApiOperation(value = "获取扫描人信息，添加数据")@GetMapping("callback")public String callback(String code, String state) {try {//从redis中将state获取出来，和当前传入的state作比较//如果一致则放行，如果不一致则抛出异常：非法访问//向认证服务器发送请求换取access_tokenString baseAccessTokenUrl = "https://api./sns/oauth2/access_token" +"?appid=%s" +"&secret=%s" +"&code=%s" +"&grant_type=authorization_code";//拼接三个参数：id 秘钥 和code值String accessTokenUrl = String.format(baseAccessTokenUrl,ConstantWxUtils.WX_OPEN_APP_ID,ConstantWxUtils.WX_OPEN_APP_SECRET,code);//请求这个拼接好的地址，得到返回两个值， access_token 和openid//使用httpclient发送请求，得到返回结果String accessTokenInfo = HttpClientUtils.get(accessTokenUrl);System.out.println("accessToken=============" + accessTokenInfo);//gson转换工具Gson gson = new Gson();HashMap<String,String> mapAccessToken = gson.fromJson(accessTokenInfo, HashMap.class);String accessToken = mapAccessToken.get("access_token");String openid = mapAccessToken.get("openid");//判断数据表里面是否有相应对的数据，根据openid判断Member member= memberService.getOpenIdMember(openid);if (member != null){return "redirect:http://localhost:3000?code=" + code + "&state=" + state;}//3 拿着得到access_token值 获取登录用户信息//访问微信的资源服务器，获取用户信息String baseUserInfoUrl = "https://api./sns/userinfo" +"?access_token=%s" +"&openid=%s";//拼接两个参数String userInfoUrl = String.format(baseUserInfoUrl,accessToken,openid);//发送请求String userInfo = HttpClientUtils.get(userInfoUrl);//获取返回userInfo字符串扫描人信息HashMap<String,String> userInfoMap= gson.fromJson(userInfo, HashMap.class);String nickname = userInfoMap.get("nickname");String headimgurl = userInfoMap.get("headimgurl");//把扫描人信息添加数据库里面member = new Member();member.setOpenid(openid);member.setNickname(nickname);member.setAvatar(headimgurl);memberService.save(member);//使用jwt根据member对象生成token字符串String jwtToken = JwtUtils.getJwtToken(member.getId(), member.getNickname());//最后:返回首页面，通过路径传递token字符串return "redirect:http://localhost:3000?token="+jwtToken;} catch (Exception e) {e.printStackTrace();throw new ELeanExeception(20001, "登录失败");}}}