content: package com.sky.service.impl;
  
  import com.alibaba.fastjson.JSON;
  import com.alibaba.fastjson.JSONObject;
  import com.sky.constant.MessageConstant;
  import com.sky.dto.UserLoginDTO;
  import com.sky.entity.User;
  import com.sky.exception.LoginFailedException;
  import com.sky.mapper.UserMapper;
  import com.sky.properties.WeChatProperties;
  import com.sky.service.UserService;
  import com.sky.utils.HttpClientUtil;
  import lombok.extern.slf4j.Slf4j;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.stereotype.Service;
  
  import java.time.LocalDateTime;
  import java.util.HashMap;
  import java.util.Map;
  
  @Service
  @Slf4j
  public class UserServiceImpl implements UserService {
  
      //微信服务接口地址
      public static final String WX_LOGIN = "https://api.weixin.qq.com/sns/jscode2session";
  
      @Autowired
      private WeChatProperties weChatProperties;
      @Autowired
      private UserMapper userMapper;
  
      /**
       * 微信登录
       * @param userLoginDTO
       * @return
       */
      public User wxLogin(UserLoginDTO userLoginDTO) {
          String openid = getOpenid(userLoginDTO.getCode());
  
          //判断openid是否为空，如果为空表示登录失败，抛出业务异常
          if(openid == null){
              throw new LoginFailedException(MessageConstant.LOGIN_FAILED);
          }
  
          //判断当前用户是否为新用户
          User user = userMapper.getByOpenid(openid);
  
          //如果是新用户，自动完成注册
          if(user == null){
              user = User.builder()
                      .openid(openid)
                      .createTime(LocalDateTime.now())
                      .build();
              userMapper.insert(user);//后绪步骤实现
          }
  
          //返回这个用户对象
          return user;
      }
  
      /**
       * 调用微信接口服务，获取微信用户的openid
       * @param code
       * @return
       */
      private String getOpenid(String code){
          //调用微信接口服务，获得当前微信用户的openid
          Map<String, String> map = new HashMap<>();
          map.put("appid",weChatProperties.getAppid());
          map.put("secret",weChatProperties.getSecret());
          map.put("js_code",code);
          map.put("grant_type","authorization_code");
          String json = HttpClientUtil.doGet(WX_LOGIN, map);
  
          JSONObject jsonObject = JSON.parseObject(json);
          String openid = jsonObject.getString("openid");
          return openid;
      }
  }