puppet conditional statement syntax error

I've checked official puppet documentation on this and the syntax looks fine, but I still get a syntax error. Can someone please check what the problem is?

I am using puppet server 3.8.

class puppet {
  if $puppet_conf == 'default' {
  }
  elseif $puppet_conf == undef {
    file { '/etc/puppet/puppet.conf':
      ensure => present,
      owner  => "root",
      group  => "root",
      mode   => "644",
      source => "puppet:///modules/puppet/puppet.conf}",
      notify => Exec['puppet-restart'],
    }

    exec { 'puppet-restart':
      command     => '/usr/bin/touch /tmp/.puppet-restart',
      refreshonly => true,
    }
  }
  else {
    file { '/etc/puppet/puppet.conf':
      ensure => present,
      owner  => "root",
      group  => "root",
      mode   => "644",
      source => "puppet:///modules/puppet/${puppet_conf}",
      notify => Exec['puppet-restart'],
    }

    exec { 'puppet-restart':
      command     => '/usr/bin/touch /tmp/.puppet-restart',
      refreshonly => true,
    }
  }
}

Error: Could not retrieve catalog from remote server: Error 400 on SERVER: Syntax error at '=='; expected '}' at /etc/puppet/modules/puppet/manifests/init.pp:6 on node

Solution

There is no elseif conditional in Puppet DSL. You need to put elsif instead. Check the documentation here for more information: https://docs.puppet.com/puppet/3.8/lang_conditional.html#syntax.