Facter for AWS EC2 Instance Tags

README.md

Installation

Check out the [Facter documentation|https://docs.puppetlabs.com/facter/2.3/custom_facts.html#loading-custom-facts]

Requirements

gem 'aws-sdk-core'

Instance must have an IAM Role with read-only permission for EC2 resources (at least ec2:Describe*). See here and here Usage:

The value of each tag can be accessed using fact aws_tag_, or all tags in JSON format using fact aws_tags. Ex:

Single tag

$ facter aws_tag_name my_ec2_instance $ facter aws_tag_environment Test All Tags

aws_tags.rb

#   aws-sdk version 2

require 'open-uri'
require 'aws-sdk-core'

def aws_metadata(path)
	return open("http://169.254.169.254/latest/meta-data/#{path}").read.split("\n")[0]
end

Aws.config[:region] = aws_metadata('placement/availability-zone')[0..-2]
Aws.config[:credentials] = Aws::InstanceProfileCredentials.new
ec2 = Aws::EC2::Client.new

filters = [
	{name: "resource-type", values: ['instance']},
	{name: "resource-id", values: [aws_metadata('instance-id')]},
]

tags = {}

ec2.describe_tags(:filters => filters).each do |resp|
	resp[:tags].each do |tag|
		tags[tag.key] = tag.value
		
		Facter.add("aws_tag_#{tag.key}") do
			setcode do
				tag.value
			end
		end
	end
end

Facter.add(:aws_tags) do
	setcode do
		tags.to_json
	end
end

aws_tags_v1.rb

# This custom fact is used to query the AWS EC2 API to determine
# the tags that has been associated with the ec2 node.
# Gem dependencies:
#   aws-sdk version 1

require 'facter'
require 'yaml'
require 'open-uri'

begin
  require 'aws-sdk'
rescue LoadError
  Facter.debug "No aws-sdk to gather facts"
end

def metadata(id = "")
  open("http://169.254.169.254/latest/meta-data/#{id||=''}").read.split("\n")[0]
rescue => details
  Facter.warn "Could not retrieve ec2 metadata: #{details.message}"
end

def region
  # Get rid of the last character of availability zone to find the region
  region = metadata('placement/availability-zone')[0..-2]
  Facter.debug "Determined region to be #{region}"
  region
end

begin
  ec2 = AWS::EC2.new
  ec2 = ec2.regions[region]
  exclusion_list=['Name']
  instance = ec2.instances[metadata('instance-id')]

  instance.tags.each do |key, value|
    if not exclusion_list.include? key
      Facter.add(key) { setcode { value } }
    end
  end
rescue => details
  Facter.warn("Unable to get ec2 tags: #{details.message}")
end