Puppet validate_cmd alternatives in Puppet 2.7 - puppet

Question

My puppet version is 2.7.25. What I would like to do is create a users home directory if it does not already exist and only if the user resides in LDAP.
I was hoping to use the exit status from this command to test upon.
/usr/bin/getent passwd username
Here is what I thought the puppet code would look like if I was running the correct version of puppet.
define ldap-users::virtual ($gid,$gname) {
$home_root = "/export/home"
file {
"${home_root}/${title}":
ensure => directory,
owner => $title,
group => $gid,
mode => 0700,
validate_cmd => "/usr/bin/getent passwd ${title}",
}
}

Answer 1

Using Felix's answer from validate_cmd in Puppet: supporting older versions, if you have puppetlabs-stdlib installed, you should be able to write some code that can do that for you. Something like this (might need modifying):
file {"${home_root}/${title}":
ensure => directory,
owner => $title,
group => $gid,
mode => '0700',
}
if versioncmp($puppetversion, '3.5') >= 0 {
File["${home_root}/${title}"] { validate_cmd => "/usr/bin/getent passwd ${title} #%"
}
else {
validate_cmd('/dev/null', '/usr/bin/getent passwd ${title} #%', "getent could not find the user specified ${title}")
}
This allows you to write backwards compatible code, that will still work when you upgrade beyond 3.5 (Which I would recommend, Puppet 2.7 has been EOL since October 1st 2013!)
Caveats
The validate_cmd is primarily used to point to a created file to run the command (such as visudo to check a sudoers file). So we can just make the validate_cmd run the getent command, and add a hash to comment out the actual file path.
Bear in mind this is not the standard usecase for the command, and will throw an error if the command fails, you might get some unexpected behaviour.
If you want a better workflow, a custom fact to check if the user exists before trying to create the folder might be a better idea:
require 'pathname'
export_home_dirs = Pathname.glob('/export/home/**')
export_home_dirs.each do |export_home|
Facter.add("export_home_user_#{export_home}") { setcode { "/export/home/#{export_home}" } }
end
Then gate your logic behind that custom fact.