调试窗口返回：POST https://xxxxx/api/code2Session 404 错误
但代码中居然进入的是success: function
wx.request({
          url: api_base_url + '/api/code2Session',
          method: 'POST',
          header: {
            'content-type': 'application/x-www-form-urlencoded'
          },
          data: {
            code: res.code,
          },
          success: function (res) {
            if(res.statusCode != 200)
            {
              console.log('wx.request错误：')
              console.log(res);
              return;
            }
            const sessionInfo = res.data.data.session_info;
            if (res.data.status == 200) {
              resolve(sessionInfo);
            } else {
              reject(res.data);
            }
          },
          fail:(res)=>{
            reject(res);
          }
        })