+Puppet::Parser::Functions.newfunction(
+ :fqdn_rotate,
+ :type => :rvalue,
+ :doc => "Usage: `fqdn_rotate(VALUE, [SEED])`. VALUE is required and
+ must be an array or a string. SEED is optional and may be any number
+ or string.
+
+ Rotates VALUE a random number of times, combining the `$fqdn` fact and
+ the value of SEED for repeatable randomness. (That is, each node will
+ get a different random rotation from this function, but a given node's
+ result will be the same every time unless its hostname changes.) Adding
+ a SEED can be useful if you need more than one unrelated rotation.",
+) do |args|
+
+ raise(Puppet::ParseError, "fqdn_rotate(): Wrong number of arguments given (#{args.size} for 1)") if args.empty?
+
+ value = args.shift
+ require 'digest/md5'
+
+ unless value.is_a?(Array) || value.is_a?(String)
+ raise(Puppet::ParseError, 'fqdn_rotate(): Requires either array or string to work with')
+ end