diff options
| -rw-r--r-- | README.markdown | 15 | ||||
| -rw-r--r-- | lib/puppet/parser/functions/fqdn_rotate.rb | 24 |
2 files changed, 29 insertions, 10 deletions
diff --git a/README.markdown b/README.markdown index c140af4..8ed3d9b 100644 --- a/README.markdown +++ b/README.markdown @@ -259,7 +259,20 @@ fqdn_rand_string(10, '', 'custom seed') #### `fqdn_rotate` -Rotates an array a random number of times, based on a node's fqdn. *Type*: rvalue. +Rotates an array or string a random number of times, combining the `$fqdn` fact and an optional seed for repeatable randomness. + +*Usage:* +~~~ +fqdn_rotate(VALUE, [SEED]) +~~~ +*Examples:* +~~~ +fqdn_rotate(['a', 'b', 'c', 'd']) +fqdn_rotate('abcd') +fqdn_rotate([1, 2, 3], 'custom seed') +~~~ + +*Type*: rvalue. #### `get_module_path` diff --git a/lib/puppet/parser/functions/fqdn_rotate.rb b/lib/puppet/parser/functions/fqdn_rotate.rb index e1a50e6..b66431d 100644 --- a/lib/puppet/parser/functions/fqdn_rotate.rb +++ b/lib/puppet/parser/functions/fqdn_rotate.rb @@ -2,16 +2,23 @@ # fqdn_rotate.rb # -module Puppet::Parser::Functions - newfunction(:fqdn_rotate, :type => :rvalue, :doc => <<-EOS -Rotates an array a random number of times based on a nodes fqdn. - EOS - ) do |arguments| +Puppet::Parser::Functions.newfunction( + :fqdn_rotate, + :type => :rvalue, + :doc => "Usage: `fqdn_rotate(VALUE, [SEED])`. VALUE is required and + must be an array or a string. SEED is optional and may be any number + or string. + + Rotates VALUE a random number of times, combining the `$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 (#{arguments.size} for 1)") if arguments.size < 1 + "given (#{args.size} for 1)") if args.size < 1 - value = arguments.shift + value = args.shift require 'digest/md5' unless value.is_a?(Array) || value.is_a?(String) @@ -31,7 +38,7 @@ Rotates an array a random number of times based on a nodes fqdn. elements = result.size - seed = Digest::MD5.hexdigest([lookupvar('::fqdn'),arguments].join(':')).hex + seed = Digest::MD5.hexdigest([lookupvar('::fqdn'),args].join(':')).hex # deterministic_rand() was added in Puppet 3.2.0; reimplement if necessary if Puppet::Util.respond_to?(:deterministic_rand) offset = Puppet::Util.deterministic_rand(seed, elements).to_i @@ -51,7 +58,6 @@ Rotates an array a random number of times based on a nodes fqdn. result = string ? result.join : result return result - end end # vim: set ts=2 sw=2 et : |