Update 2020 Feb 24:
It would be wise to stay tuned with it. Here is the link for latest library instruction:
You haven’t started your monogo database. first install mongo install mongo as per your OS https://docs.mongodb.com/v3.0/tutorial/
then follow instructions mentioned on this site: https://docs.mongodb.com/v3.0/tutorial/getting-started-with-the-mongo-shell/
- cd .
- mongod –dbpath “any directory path to start your database “
and then start your node server. It will work fine.
Hope this helps!!