diff options
Diffstat (limited to 'code/environments/production/modules/stdlib/lib/puppet/parser/functions/seeded_rand.rb')
| -rw-r--r-- | code/environments/production/modules/stdlib/lib/puppet/parser/functions/seeded_rand.rb | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/code/environments/production/modules/stdlib/lib/puppet/parser/functions/seeded_rand.rb b/code/environments/production/modules/stdlib/lib/puppet/parser/functions/seeded_rand.rb new file mode 100644 index 0000000..0120b87 --- /dev/null +++ b/code/environments/production/modules/stdlib/lib/puppet/parser/functions/seeded_rand.rb @@ -0,0 +1,24 @@ +# +# seeded_rand.rb +# +Puppet::Parser::Functions.newfunction( + :seeded_rand, + :arity => 2, + :type => :rvalue, + :doc => <<-DOC + 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`. +DOC +) do |args| + require 'digest/md5' + + raise(ArgumentError, 'seeded_rand(): first argument must be a positive integer') unless function_is_integer([args[0]]) && 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 |