• What is Gem 

1. Gem is the open source library that contain Ruby code and are packaged with a little extra data . 
2. Gem allows a programmer to use the code within the gem in their own program, without explicitly inserting that code.

There are several gems as follows:  

1. RSpec — A testing framework that supports Behavior Driven  Development for Ruby.
2. Devise — Devise works with authentication. For any website that needs to user log-in’s, Devise handles sign in, sign up, reset password, etc

Generate the Gem Skeleton: Use the Bundler gem to generate a new gem skeleton.

Run: bundle gem hello_world_gem

 

bundle gem  hello_world_gem 

File Structure:

• lib:Directory where your gem's code resides. hello_world_gem.rb: Ruby file containing your gem's code.
• spec (optional): Directory for your gem's test suite.
• Gemfile and Gemfile.lock: Files that Bundler uses to manage your gem's dependencies.
• hello_world_gem.gemspec: Gem specification file where you define metadata about your gem.
• README.md: File containing documentation for your gem.

Implement the Code :

• Implement the "Hello, World!" functionality. Open the lib/hello_world_gem.rb file

 

module HelloWorldGem
        def self.say_hello
          puts “Hello,World!”
      end
end

Setup the .gemspec configration:

 

require_relative "lib/hello_world_gem/version"

Gem::Specification.new do |spec|

spec.name = "hello_world_gem"
spec.version = HelloWorldGem::VERSION
spec.authors = ["test test"]
spec.email = ["[email protected]"]
spec.summary = "Print the HelloWorld"
spec.description = "Print the HelloWorld"
spec.homepage = "https://github.com/test/hello_world_gem"
spec.required_ruby_version = ">= 2.6.0"
spec.metadata["allowed_push_host"] = "https://rubygems.org"
spec.metadata["homepage_uri"] = spec.homepage
spec.metadata["source_code_uri"] = "https://github.com/test/two_factor_auth_gem"
spec.metadata["changelog_uri"] = "https://github.com/test/two_factor_auth_gem/blob/main/CHANGELOG.md"

#Specify which file should be added to the gem when it is released.
#The 'git ls-files -z' loads the files in the RubyGem that have been added into git.
spec.files = Dir.chdir(_dir_) do
    'git ls-files -z'.split("\x0").reject do |f|
        (File.expand_path(f) == _FILE_) || 
           f.start_with?(*%w[bin/ test/ spec/ featues/ .git .circleci appveyor Gemfile])
          end
    end
spec.bindir = "exe"
spec.executables = spec.files.grep(%r{\Aexe/}) { |f| File.basename(f) }
spec.require_paths = ["lib"]
end

 

Gem Build:

• Build the Gem Package: 
• Run : gem build hello_world_gem.gemspec
• This command will create a .gem file in your directory, which is the packaged gem ready for distribution. 

gem build  hello_world_gem.gemspec 

 

•  How to push Gem 

    Step 1: Create the account on the rubygem.org
    Step2: Navigate your gem directory
    Step 3: Run: gem signin Add your credentials and make sure show_dashboard is enable
    Step 4: Push : gem push hello_world_gem-0.1.0.gem

 

gem signin
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