From ba6dd13990b2e9f80ef08b067d28a155640d05ef Mon Sep 17 00:00:00 2001 From: Gary Larizza Date: Fri, 3 Aug 2012 15:46:26 -0700 Subject: Add the pick() function 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. --- lib/puppet/parser/functions/pick.rb | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) create mode 100644 lib/puppet/parser/functions/pick.rb (limited to 'lib/puppet/parser/functions') diff --git a/lib/puppet/parser/functions/pick.rb b/lib/puppet/parser/functions/pick.rb new file mode 100644 index 0000000..cbc0300 --- /dev/null +++ b/lib/puppet/parser/functions/pick.rb @@ -0,0 +1,29 @@ +module Puppet::Parser::Functions + newfunction(:pick, :type => :rvalue, :doc => <<-EOS + +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. + +EOS +) do |args| + args = args.compact + args.delete(:undef) + args.delete(:undefined) + args.delete("") + if args[0].to_s.empty? then + fail "Must provide non empty value." + else + return args[0] + end + end +end -- cgit v1.2.3