8aecd63378
seeded_rand is needed for repeatable randomness across nodes in a cluster
22 lines
794 B
Ruby
22 lines
794 B
Ruby
Puppet::Parser::Functions::newfunction(
|
|
:seeded_rand,
|
|
:arity => 2,
|
|
:type => :rvalue,
|
|
:doc => <<-EOS
|
|
Usage: `seeded_rand(MAX, SEED)`. MAX must be a positive integer; SEED is any string.
|
|
|
|
Generates a random whole number greater than or equal to 0 and less
|
|
than MAX, using the value of SEED for repeatable randomness. If SEED
|
|
starts with "$fqdn:", this is behaves the same as `fqdn_rand`.
|
|
|
|
EOS
|
|
) do |args|
|
|
require 'digest/md5'
|
|
|
|
raise(ArgumentError, "seeded_rand(): first argument must be a positive integer") unless function_is_integer([args[0]]) and args[0].to_i > 0
|
|
raise(ArgumentError, "seeded_rand(): second argument must be a string") unless args[1].is_a? String
|
|
|
|
max = args[0].to_i
|
|
seed = Digest::MD5.hexdigest(args[1]).hex
|
|
Puppet::Util.deterministic_rand(seed,max)
|
|
end
|