How to set proccess.env in Node express app on heroku

Question

I have a simple node with mongo (via mongojs) app that is developed locally and deployed on heroku. In my development environment, i want to use a local instance of mongo, while in production, I would like to use the instance heroku provides to me via "process.env.MONGOLAB_URI".

My current approach is that I would set the datavase url depending on the environment variable, but how do i actually go into production mode? Moreover, how can i configure this so that when i develop on my local machine its development mode, when i upload to heroku its production mode?

app.configure('production', function(){
  // ...
  databaseUrl = "mydb"; // the default
});

app.configure('development', function(){
  // ...
  databaseUrl = process.env.MONGOLAB_URI;
});

db = require("mongojs").connect(databaseUrl);

Answer 1

Set the NODE_ENV environment variable to "development" on your local environment, and set it to "production" on Heroku. https://devcenter.heroku.com/articles/nodejs#setting-node-env