Because no one should have to figure out how to do this again. A recursive way to convert a Ruby hash into raw xml.

hash_to_xml.rb

# this method is used to create a full XML structure for the Freshbooks API
# don't expect it to work for anything else
def to_xml(data_hash)
  req_method = data_hash.delete(:method)
  '<?xml version="1.0" encoding="utf-8"?>' +
    "<request method=\"#{req_method}\">" +
      hash_to_raw_xml(data_hash) +
    '</request>'
end

# converts a hash to raw XML
def hash_to_raw_xml(object, built = '')
  case object
  when Hash
    case
    when object.count > 1
      object.each { |h| built += "<#{h.first.to_s}>#{hash_to_raw_xml(h.last)}</#{h.first.to_s}>" }
    when object.count == 1
      object.each { |h| built += "<#{h.first.to_s}>#{hash_to_raw_xml(h.last, built)}</#{h.first.to_s}>" }
    end
  when String
    built += object
  end
  built
end