36 lines
1.2 KiB
Ruby
36 lines
1.2 KiB
Ruby
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module Puppet::Parser::Functions
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newfunction(:pick_default, :type => :rvalue, :doc => <<-EOS
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This function is similar to a coalesce function in SQL in that it will return
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the first value in a list of values that is not undefined or an empty string
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(two things in Puppet that will return a boolean false value). If no value is
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found, it will return the last argument.
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Typically, this function is used to check for a value in the Puppet
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Dashboard/Enterprise Console, and failover to a default value like the
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following:
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$real_jenkins_version = pick_default($::jenkins_version, '1.449')
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The value of $real_jenkins_version will first look for a top-scope variable
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called 'jenkins_version' (note that parameters set in the Puppet Dashboard/
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Enterprise Console are brought into Puppet as top-scope variables), and,
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failing that, will use a default value of 1.449.
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Note that, contrary to the pick() function, the pick_default does not fail if
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all arguments are empty. This allows pick_default to use an empty value as
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default.
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EOS
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) do |args|
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fail "Must receive at least one argument." if args.empty?
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default = args.last
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args = args[0..-2].compact
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args.delete(:undef)
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args.delete(:undefined)
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args.delete("")
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args << default
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return args[0]
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end
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end
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