Puppet Function: seeded_rand_string

Defined in:
lib/puppet/functions/seeded_rand_string.rb
Function type:
Ruby 4.x API

Summary

Generates a consistent random string of specific length based on provided seed.

Overview

seeded_rand_string(Integer[1] $length, String $seed, Optional[String[2]] $charset) ⇒ String

Examples:

Generate a consistently random string of length 8 with a seed:

seeded_rand_string(8, "${module_name}::redis_password")

Generate a random string from a specific set of characters:

seeded_rand_string(5, '', 'abcdef')

Parameters:

  • length (Integer[1]) —

    Length of string to be generated.

  • seed (String) —

    Seed string.

  • charset (Optional[String[2]]) —

    String that contains characters to use for the random string.

Returns:

  • (String) —

    Random string.



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# File 'lib/puppet/functions/seeded_rand_string.rb', line 11

Puppet::Functions.create_function(:seeded_rand_string) do
  # @param length Length of string to be generated.
  # @param seed Seed string.
  # @param charset String that contains characters to use for the random string.
  #
  # @return [String] Random string.
  dispatch :rand_string do
    param 'Integer[1]', :length
    param 'String', :seed
    optional_param 'String[2]', :charset
  end

  def rand_string(length, seed, charset = nil)
    require 'digest/sha2'

    charset ||= '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'

    random_generator = Random.new(Digest::SHA256.hexdigest(seed).to_i(16))

    Array.new(length) { charset[random_generator.rand(charset.size)] }.join
  end
end