external_ipaddress.rb

#
# Author:: Joshua Timberman <opensource@housepub.org>
# Copyright:: Copyright (c) 2012, Joshua Timberman
# License:: Apache License, Version 2.0
#
# Ohai Plugin: external_ipaddress
#
# Save this to /etc/chef/ohai_plugins/external_ipaddress.rb, then run ohai with:
#
#    ohai -d /etc/chef/ohai_plugins external_ipaddress
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
provides "external_ipaddress"

require 'open-uri'
require 'json'

ipaddr = nil

begin
  open("http://jsonip.com").each {|i| ipaddr = JSON.parse(i)['ip']}
  Ohai::Log.debug("Using #{ipaddr} for the external IP address.")
rescue
  Ohai::Log.debug("Could not determine external IP address from 'jsonip.com'")
end

external_ipaddress ipaddr