微信小程序登录流程

onLoad() {
    this.serviceIp = this.GLOBAL.serviceIp;
    var that = this;
    // #ifdef H5
    uni.switchTab({
      url: '../index/index'
    });
    // #endif

    // #ifdef MP-WEIXIN
    wx.getSetting({
      success(res) {
        //判断是否 授权用户信息
        if (!res.authSetting['scope.userInfo']) {
          //授权 会弹出 用户授权框 
          wx.authorize({
            scope: 'scope.userInfo',
            success() {
              //登录
              that.wxgetInfo();
            }
          });
        } else {
          // 登录
          that.wxgetInfo();
        }
      }
    });
    // #endif
  },
  methods: {
    wxgetInfo: function() {
      let that = this;
      //获取 用户信息 然后 去登录
      wx.getUserInfo({
        success(res) {
          let userInfo=res.userInfo;
          that.wxlogin(userInfo.nickName ,userInfo.avatarUrl);
        }
      });
    },
    wxlogin: function(nickName,avatarUrl) {
      let that = this;
      wx.login({
        success(res) {
          if (res.code) {
            // 发起网络请求
            wx.request({
              url: that.serviceIp + 'wxmini/wxlogin',
              data: {
                code: res.code,
                // 中文解决方案
                nickName:encodeURI(nickName),
                avatarUrl:avatarUrl
              },
              success(res) {
                uni.setStorageSync('storage_usermodel', res.data.obj);
                uni.switchTab({
                  url: '../index/index'
                });
              }
            });
          } else {
            console.log('登录失败！' + res.errMsg);
          }
        }
      });
    }
  }

//服务器 通过
https://api.weixin.qq.com/sns/jscode2session?appid=appid&secret=appsecret&js_code=code&grant_type=authorization_code

获取 openId 和 session_key 注册用户数据 进行保存
处理完后 返回给 客户端