logger.js

// adds a persitant server-side logger to the Sammy logger pool

Sammy.addLogger(function() {
  var message = $.makeArray(arguments).join(', ');
  // dont provide a callback (aka ignore the results)
  $.post('/log', "message=" + message);
});

Sammy.log('logging', 'should', 'be', 'working');
// POST /log
// body: message=[TIMESTAMP], logging, should, be, working

sammy_logger.rb

# super simple sinatra app that logs messages posted to /log to sammy.log

require 'sinatra'
require 'logger'

LOGGER = Logger.new('sammy.log')

post '/log' do
  LOGGER.info params[:message].to_s.split(', ').join("\t")
end