Rails 2.3 session patched to use JSON

Rails JSON Sessions

# Typically this would go in a file in /config/initializers. Note you'll also need
# the json gem (ideally native) and then specify this in your environment:
#   ActiveSupport::JSON.backend = 'JSONGem'

# A bit of Rails magic to change the way the session is "marshalled". Essentially
# this bit of monkeypatching makes the MemCacheStore use JSON instead of the 
# default Ruby marshalling in order to share data seamlessly with the node.js
# portion of the app.
# TODO: combine with a persistent store or convert to redis to better preserve
#       sessions for lurkers
module ActionController
  module Session
    class MemCacheStore < AbstractStore
      private
        def get_session(env, sid)
          sid ||= generate_sid
          begin
            getval = @pool.get(sid, true)
            session_strkeys = (getval && ActiveSupport::JSON.decode(getval)) || {}            
            # Convert all the keys from strings to symbols for broader compatibility
            session = session_strkeys.inject({}){|memo,(k,v)| memo[k.to_sym] = v; memo}
            # session = session_strkeys
          rescue MemCache::MemCacheError, Errno::ECONNREFUSED
            session = {}
          end
          [sid, session]
        end

        def set_session(env, sid, session_data)
          options = env['rack.session.options']
          expiry  = options[:expire_after] || 0
          @pool.set(sid, session_data.to_json, expiry, true)
          return true
        rescue MemCache::MemCacheError, Errno::ECONNREFUSED
          return false
        end
    end
  end
end