Rails, Mongoid & Unicorn config for Heroku
You dont actually need to do this, so for people coming to view this question see:
http://mongoid.org/en/mongoid/docs/rails.html
"Unicorn and Passenger
When using Unicorn or Passenger, each time a child process is forked when using app preloading or smart spawning, Mongoid will automatically reconnect to the master database. If you are doing this in your application manually you may remove your code."
Though it would still be interesting to know what would be the equivalent Mongoid code.
What about::Mongoid.default_session.connect::Mongoid.default_session.disconnect
https://docs.mongodb.com/mongoid/current/tutorials/mongoid-configuration/#usage-with-forking-servers
The documentation on mongodb.com says that after_fork and before_fork for unicorn or passenger are required.
This probably changed recently. This is the 7.0 mongoid documentation