vhosts recipe for one-day Introduction to Chef workshop

vhosts.rb

data_bag("vhosts").each do |site|
  site_data = data_bag_item("vhosts", site)
  site_name = site_data["id"]
  document_root = "/srv/apache/#{site_name}"
 
  template "/etc/httpd/conf.d/#{site_name}.conf" do
    source "custom-vhosts.erb"
    mode "0644"
    variables(
      :document_root => document_root,
      :port => site_data["port"]
    )
    notifies :restart, "service[httpd]"
  end
 
  directory document_root do
    mode "0755"
    recursive true
  end
 
  template "#{document_root}/index.html" do
    source "index.html.erb"
    mode "0644"
    variables(
      :site_name => site_name,
      :port => site_data["port"]
    )
  end
end

Hi,

I have been following tutorial for chef and could see this code into the tutorial by Nathen, Can anyone explain this code please?