How-to Create a Ruby CLI Gem

ruby-cli-gem.md

How-to Create a Ruby CLI Gem

Pre-Setup

1. Create a RubyGems Account
2. Install RVM (Ruby Version Manager) : RVM
3. Install Bundler: gem install bundler

Project Creation

1. Navigate to the parent directory you want to create your gem repository directory in.
2. Create Gemset: rvm gemset create yourGemName
3. Use Gemset: rvm gemset use yourGemName
4. Bundle Gem: bundle gem yourGemName
5. Open the app's parent file located at lib/yourGemName.rb
6. Create a Hello World output

require "yourGemName/version"

module yourGemName
  class Test
    def say_hello
      puts "Hello World!"
    end
  end
end

7. Create an executable file at bin/yourGemName (no file extension)
8. Add Shebang #!/usr/bin/env ruby and code to call your Hello World output

#!/usr/bin/env ruby

require 'yourGemName'

test = yourGemName::Test.new
test.say_hello

9. Create a CHANGELOG.md file in the project directory
10. Create repository on Github
11. Make initial commit: git commit -m "Initial commit"
12. Push code to repository on Github:

git remote add origin git@github.com:yourusername/yourGemRepo.git
git push -u origin master

12. Open gemspec - /yourGemName.gemspec
13. Update todo lines:
    1. Update spec.summary
    2. Update spec.descriptions
    3. Update spec.homepage
    4. Update spec.metadata["source_code_uri"] (Github Repo Page)
    5. Update spec.metadata["changelog_uri"] (Github CHANGELOG.md link)
    6. Update spec.bindir to bin
    7. Update spec.executeables to yourGemName (the file in /bin)
14. Run Bundle Install: bundle install
15. Build Binary: rake install
16. Test output: yourGemName --> "Hello World"

Deploying Gem

17. Commit Changes to Github
18. Build Gem: gem build yourGemName
19. Push Gem to RubyGems.org: gem push yourGemName-0.1.0.gem