I am looking to deploy my rails app into an environment that I don't control. I don't want some (future) change in gems to break the app. So I am using
rake rails:freeze:gems
to freeze the rails version and
rake gems:unpack rake gems:unpack:dependencies
to freeze the gems in use.
As I understand it this will make the app use the versions of code in vendor/ and it doesn't matter what gems are added/removed/upgraded on the server. Is this correct?
Now to my real question, 'rake gems:unpack' only works for gems listed in config/environment.rb. How do I find gems that are in use by my app, but are not listed there? I know all gems should be listed, but I didn't always know that and I still need to future-proof my older apps.
Thanks,
Matt