Puppet Function: pick

Defined in:
modules/stdlib/lib/puppet/parser/functions/pick.rb
Function type:
Ruby 3.x API

Overview

pick()Any

This function is similar to a coalesce function in SQL in that it will return the first value in a list of values that is not undefined or an empty string (two things in Puppet that will return a boolean false value). Typically, this function is used to check for a value in the Puppet Dashboard/Enterprise Console, and failover to a default value like the following:

$real_jenkins_version = pick($::jenkins_version, '1.449')

The value of $real_jenkins_version will first look for a top-scope variable called 'jenkins_version' (note that parameters set in the Puppet Dashboard/ Enterprise Console are brought into Puppet as top-scope variables), and, failing that, will use a default value of 1.449.

Returns:

  • (Any)


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# File 'modules/stdlib/lib/puppet/parser/functions/pick.rb', line 5

newfunction(:pick, :type => :rvalue, :doc => <<-DOC
  This function is similar to a coalesce function in SQL in that it will return
  the first value in a list of values that is not undefined or an empty string
  (two things in Puppet that will return a boolean false value). Typically,
  this function is used to check for a value in the Puppet Dashboard/Enterprise
  Console, and failover to a default value like the following:

    $real_jenkins_version = pick($::jenkins_version, '1.449')

  The value of $real_jenkins_version will first look for a top-scope variable
  called 'jenkins_version' (note that parameters set in the Puppet Dashboard/
  Enterprise Console are brought into Puppet as top-scope variables), and,
  failing that, will use a default value of 1.449.
DOC
           ) do |args|
  args = args.compact
  args.delete(:undef)
  args.delete(:undefined)
  args.delete('')
  raise Puppet::ParseError, 'pick(): must receive at least one non empty value' if args[0].to_s.empty?
  return args[0]
end