Auth testing
06/04/2018 This will work both on normal desktop Windows or Linux with the latest mongodb distro
and
Raspbian Stretch and mongodb version 3.0.14 from this site: https://andyfelong.com/2017/08/mongodb-3-0-14-for-raspbian-stretch/#more-727
tried to pull the latest mongodb distro from the official repo but it doesn't work with hte latest nodejs mongoose module.
The distro from Andy Felong takes a bit of doing to install and get going, but works perfectly. Actually to be fair, the problems I had were more to do with my lack of knowledge of Linux commands that anything else.
if you already have an instalation of mongodb the best option is to delete all the files and folders he's asking you to modify or make. at this point, I'm not sure what this will do to your data file but it looks that it should all still be there. Needs checking.