Deferred puppet function

get_vpc.rb

require 'aws-sdk-ec2'

Puppet::Functions.create_function(:'amazon_aws::get_vpc') do
  dispatch :up do
    param 'String', :vpc_name
  end
  def up(vpc_name)
    client = Aws::EC2::Client.new(region: 'us-west-2')

    vpc_id = ""
    client.describe_vpcs.each do |response|
      response.vpcs.each do |vpc|
	      name = vpc.tags.find { |x| x.key == 'Name' } unless vpc.tags.nil?
	      vpc_id = vpc.vpc_id if !name.nil? and name.value == vpc_name
      end
    end
    vpc_id
  end
end

/etc/puppetlabs/code/modules/amazon_aws/lib/puppet/functions/amazon_aws/get_vpc.rb

$vpc_name = "ghdefvpc"
$vpc_get = Deferred("amazon_aws::get_vpc", [$vpc_name])

aws_vpc { $vpc_name:
ensure => present,
name => $vpc_name,
cidr_block => "10.182.0.0/16",
}

aws_security_group { 'ghdefsg':
name => 'ghdefsg',
group_name => 'ghdefsg',
description => 'big desc',
vpc_id => $vpc_get,
ensure => present
}