Connecting to MongoDB database on mLab fails authentication

As of March 2016, mLab.com only supports mongo 3.0+ (as per a conversation with support), because of their new onerous authentication requirements.

This was not on the website, but I hope it helps someone here!

You can get the dbuser and dbpass with:

heroku config | grep MONGODB_URI

Grab the dbuser (example_user) and dbpass (example_pass) from the response:

MONGOLAB_URI: mongodb://example_user:[email protected]:12345/db