35 lines
1.2 KiB
Ruby
35 lines
1.2 KiB
Ruby
module Puppet::Parser::Functions
|
|
newfunction(:pick_default, :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). If no value is
|
|
found, it will return the last argument.
|
|
|
|
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:
|
|
|
|
$real_jenkins_version = pick_default($::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.
|
|
|
|
Note that, contrary to the pick() function, the pick_default does not fail if
|
|
all arguments are empty. This allows pick_default to use an empty value as
|
|
default.
|
|
|
|
EOS
|
|
) do |args|
|
|
fail "Must receive at least one argument." if args.empty?
|
|
default = args.last
|
|
args = args[0..-2].compact
|
|
args.delete(:undef)
|
|
args.delete(:undefined)
|
|
args.delete("")
|
|
args << default
|
|
return args[0]
|
|
end
|
|
end
|