JingYan Dual Axis Digital Protractor is tool to get angle to level.
This is a node.js version driver for it.
You can buy it from here: https://item.taobao.com/item.htm?id=15923667039&ali_refid=a3_430582_1006:1104879675:N:%E7%94%B5%E5%AD%90%E6%B0%B4%E5%B9%B3%E4%BB%AA:2f73115d216112bea92c65fbcb9e9a5d&ali_trackid=1_2f73115d216112bea92c65fbcb9e9a5d&spm=a230r.1.14.11#detail.