ec2 tags to facts. It requires aws-cli (pip install aws-cli)

ec2_tags.rb

require 'facter'
require 'json'

instance_id = Facter.value("ec2_instance_id")
region = Facter.value("ec2_placement_availability_zone")[0..-2]
tags = Facter::Util::Resolution.exec("/usr/local/bin/aws ec2 describe-tags --filters \"Name=resource-id,Values=#{instance_id}\" --region #{region} | cut -f 4-")

parsed_tags = JSON.parse(tags)
parsed_tags['Tags'].each do |tag|
  Facter.add("ec2_tag_#{tag["Key"]}") do
    setcode do
      "#{tag["Value"]}"
    end
  end
end