I built this... I'm not proud... but yea, it works....

parse_yaml_for_bash.rb

#!/usr/bin/env ruby
#
# Parses a given yaml file and returns prefix_key=value
#    Usage: parse_yaml_for_bash <yaml_file> <prefix>

require 'yaml'

unless ARGV[0]
  puts "Usage: parse_yaml_for_bash <yaml_file> <optional prefix>"
  exit 1
end

@prefix = ARGV[1]
data    = YAML.load_file(ARGV[0])

def tree(hash, path = [])
  hash.each do |k,v|
    new_path = path + [k]
    if v.is_a?(Hash) 
      puts "#{@prefix}_#{new_path.join('_').gsub('-', '_')}_keys_count=\"#{v.keys.count}\""
      tree(v, new_path)
    else
      leaf(v, new_path)
    end
  end
end


def leaf(v, path = [])
  if v.is_a?(Array)
    puts "#{@prefix}_#{path.join('_').gsub('-', '_')}_keys_count=\"#{v.length}\""
    puts "#{@prefix}_#{path.join('_').gsub('-', '_')}=\"#{v.join(' ')}\""
  else
    puts "#{@prefix}_#{path.join('_').gsub('-', '_')}=\"#{v}\""
  end
end

tree data

to use in bash... just do eval $(parse_yaml_for_bash <file>)

mind putting a license on this? (personally I'd recommend either MIT or ASLv2)