Running Gem Server to View Docs for Ruby Libraries on Localhost

gem server

will boot up documentation on port 8808 by default pass it the -p flag followed by the port number to change.

gem server -p3000

Gem Information with Gem List

If you want to get version information about a gem the easiest way to do it is with this command

gem list <gem name>

For example

gem list activemerchant

will output the activemerchant versions I have installed. You can pass only part of the name like

gem list a

get the names of all gems (and versions) that start with “a”. There are a lot more options so here is a link to the gem command reference http://rubygems.org/read/chapter/10

The commands here are useful if you’ve installed a gem but the version you’ve configured in your environment.rb file is different. To quickly grab the right version, this command is pretty handy.