load_vars.rb

# vim: set ts=2 sw=2 et :
#
# load_data loads varibles from external yaml file.
# 
# EXAMPLE 1:
# data.yaml:
# --
# host1.client.com:
#   abc: def
#   foo: bar
#   test: other
# host2.client.com:
#   abc: abc
#   foo: baz
#   test: other2
#
# load_vars("/etc/puppet/data.yaml", "$fqdn")
# will try to find matching $fqdn key in data.yaml
# and, if found, will add variables $abc $foo and $test
#
#
# EXAMPLE 2:
# data-host1.client.com.yaml
# abc: def
#
# load_vars("/etc/puppet/data-$fqdn.yaml")
# will add variable $abc
Puppet::Parser::Functions.newfunction(:load_vars, :type => :statement) do |args|
  data = {}

  file = args[0]
  key  = args[1] if args[1]

  if File.exists?(file)
    data = YAML.load_file(file)
    
    raise(ArgumentError, "Data in %s is not a hash" % file) unless data.is_a?(Hash)

    data = data[key] if key and data[key].is_a?(Hash)
  end

  data.each { |param, value| setvar(param, strinterp(value)) }
end