shared_context_poc.rb

require 'git'

module Metadata
  class SharedContext

    attr_reader :state

    def initialize
      @state ||= []
    end

    def get_state(state_name)
    end

    def append_state(state)
      @state << state
    end
  end
end


module Action
  module Type
    Base = 'base'
    Git = 'checkout.git'
  end

  module Status
    Success = 'execute.success'
    Failed = 'execute.failed'
    RuntimeError = 'runtime.error'
  end

  class BaseAction
    attr_reader :shared_context

    def initialize(shared_context)
      @shared_context = shared_context
    end

    def execute
      @shared_context.append_state({ 
        type: Type::Base, 
        status: Status::Success,
        data: {}
      })
    end
  end

  class GitAction < BaseAction
    attr_reader :repository
    attr_reader :origin
    attr_reader :branch

    def initialize(shared_context, repository, remote = 'origin', branch = 'master')
      @repository = repository
      @branch = branch
      @name = File.basename(repository, '.*')   
      super(shared_context)
    end

    def execute
      begin
        repo = Git.clone(@repository, @name, :branch => @branch)
        revision = repo.log.first
        author = {
          name: revision.author.name,
          email: revision.author.email
        }
        status = Status::Success
        data = {
          branch: repo.branch.full,
          author: author,
          message: revision.message,
          date: revision.date,
          sha: revision.sha
        }
      rescue Git::GitExecuteError => e
        status = Status::Failed
        data = {
          message: e.message
        }
      rescue Exception => e
        status = Status::RuntimeError
        data = {
          message: e.message
        }
      ensure
        @shared_context.append_state(
          type: Type::Git,
          status: status,
          data: data
        )
      end     
    end
  end
end
context = Metadata::SharedContext.new

Action::GitAction.new(context, 'https://github.com/rbenv/ruby-build.git').execute
Action::GitAction.new(context, 'https://github.com/rbenv/ruby-build.git').execute

p context.state