Puppet: minimalistic custom fact

in your module, create a lib/facter folder.
There, create a customxpathversion.rb file containing this code:

require 'puppet'

Facter.add("customxpathversion") do
  setcode 'cat /opt/oracle/scripts/config/customxpathversion.txt'
end

where the file customxpathversion.txt contains "1.10"

Now if in your puppet code you do

notify { "${::customxpathversion}" : }

you get 1.10

Of course one should handle errors etc. But it works and I don't have to bother about $LOAD_PATH. From command line "facter customxpathversion" will not work because probably it's not in the LOAD_PATH.
Here the whole documentation Update: you can use this custom fact from the facter command line if you set the FACTERLIB environment variable:

find / -name customxpathversion*

/tmp/vagrant-puppet-3/modules-0/pippo/lib/facter/customxpathversion.rb
^C
[soa@osb-vagrant ~]$ export FACTERLIB=/tmp/vagrant-puppet-3/modules-0/pippo/lib/facter/
[soa@osb-vagrant ~]$ facter customxpathversion
1.10