make redis client available in route

in my app.js, i have constructed a redis client:

var redis = require('redis'),
  redisClient = redis.createClient(6379, 'localhost');

...

module.exports = {
  app:app,
  redisClient:redisClient
}

i need to use the redis client in my other module, which is routes/index.js. here, i tried including it like so:

var redisClient = require('../app').redisClient;

unfortunatly, it is undefined. should i just require it in the index.js like i did in the app.js, and create a new instance here? or what could i change to make it work?