use ruby fog to search which users owns an IAM key

search_iam_key.rb

#!/usr/bin/env ruby

# If you have many IAM users, it's not easy to find which user
# owns a particular IAM key from the console.
# This script can be run with the first argument as the access key id.

require 'rubygems'
require 'ap'   # gem install awesome_print
require 'fog'  # gem install fog

# the aws_credentials var is not needed if you keep keys in ~/.fog file as yaml:
# http://fog.io/about/getting_started.html

# aws_credentials = {
#       :aws_access_key_id => '',
#       :aws_secret_access_key => ''
# }
#iam = Fog::AWS::IAM.new(aws_credentials)

iam = Fog::AWS::IAM.new   # pick up vars from ~/.fog

users = iam.list_users.body["Users"]

puts "Searching for #{ARGV[0]} ..."
users.each do |user|
  u = user["UserName"]
  access_keys = iam.list_access_keys('UserName' => u).body["AccessKeys"]
  access_keys.each do |key|
    if key["AccessKeyId"] == ARGV[0]
      ap iam.get_user(u).body
      exit 0
    end
  end
end
# ToDo: list groups and maybe policies.
puts "Not found"
exit 1