pull.pp

define placeholder() {
  # Nothing to do, it's a placeholder!
}

class bar {
  Placeholder <<| title == "importantserver" |>> { before => File['/tmp/y'] }

  file {
    "/tmp/y":
      content => "Importantserver is ready!\n";
  }
}

include bar

push.pp

define placeholder() {
  # Nothing to do, it's a placeholder!
}

class foo {
  @@placeholder { 
    "importantserver":
  }
}

include foo

Running it

# The first run fails because there is no 'importantserver' placeholder resource.
frontend1(~) % puppet apply --storeconfigs --config ./puppet.conf pull.pp
Could not find dependency Placeholder[importantserver] for File[/tmp/y] at /home/jordan/pull.pp:12

# Have another server export this resource
ops(~/pp) % puppet apply --storeconfigs --config ./puppet.conf push.pp

# Try again, which works because the exported resource is found.
frontend1(~) !1! % puppet apply --storeconfigs --config ./puppet.conf pull.pp
notice: /Stage[main]/Bar/File[/tmp/y]/content: content changed '{md5}5a2f711ba4198f0db5e6b9e38a8f2d64' to '{md5}53cadf1c93f077aae3747e6507d7aa8e'