example for https://tutsplus.com/course/virtual-machines-with-vagrant-and-puppet/

webserver.pp

class webserver{
  case $operatingsystem {
    ubuntu: {
      $apache = 'apache2'
      $configfile = '/etc/apache2/sites-enabled/000-default'
    }
  }

  package { 'apache':
    name   => $apache,
    ensure => 'installed',
  }

  file { 'site-config':
    path    => $configfile,
    source  => '/vagrant/manifests/site-config',
    require => Package['apache'],
  }

  service { 'apache':
    name       => $apache,
    ensure     => 'running',
    hasrestart => true,
    subscribe  => File['site-config']
  }

  file { '/vagrant/index.html':
    content => "<h1> vagrant + puppet + ${apache} + ${operatingsystem}</h1>",
  }

  if $apache == 'apache2' {
  }
}