scratch.rb

repodir = '/etc/yum.repos.d/'

# remove all undesired (unspecified) repos
Dir[repodir + '*.repo'].each do |file_name|
  repo_name = File.basename(file_name, '.repo')
  unless node['software']['repo'].values.member?(repo_name)
    yum_repository repo_name do
      action :delete
    end
  end
end