Devise is my preferred gem for introducing user authentication into a Rails project. In Rails 3, it’s easy to install but if you attempt to run the devise:install generator, you may receive this message:
Could not find generator devise:install
Edit: Stib left a comment about the change to the generator. The original content for this post is below.
Rails doesn’t recognize that the gem is needed so it doesn’t load it. Simply add the following line to your Gemfile (assuming 1.3.4 is your working version):
gem 'devise', '1.3.4'