Which Ruby formatter extension on VSCode is easiest to configure?

I have tried setting up a VSCode formatter with the Ruby, Rufo and Rubocop VSCode extensions and, while I consider myself a pretty solid programmer, I am at a complete loss on this one. Each extension seems to either want me to connect it to bundler, or connect it to a local executable on my system. Why is this necessary? Has anyone developed an extension that will just take a ruby file, regardless of the surrounding context, and format it into a Ruby file that has proper indentation? If anyone can direct me to something like this, it would make my life a lot easier. :) Please help if you can.