百度小程序第一步
获取 access_token https://smartprogram.baidu.com/docs/develop/serverapi/power_exp/
获取 session_key https://smartprogram.baidu.com/docs/develop/api/open/getSessionKey/
登录流程 https://smartprogram.baidu.com/docs/develop/function/login_process/
单登录 https://smartprogram.baidu.com/docs/develop/function/login/
获取手机号码 https://smartprogram.baidu.com/docs/develop/function/login_union/
获取用户信息 https://smartprogram.baidu.com/docs/develop/function/getuserinfo/