Because Swing Out London's source is available on Github, a number of secret items live outside it in environment variables:
First you'll need to generate a secret token (this lives outside the app):
% rake secret
% >> ba66a824fff6ff0ea2d8...
Set this to the relevant environment variable - I suggest adding this to your .rvmrc
if you're using RVM:
% export SWINGOUTLONDON_SECRET_TOKEN="ba66a824fff6ff0ea2d8..."
You'll also need to set these wherever you're deploying the site. For Heroku you'd run:
% heroku config:set SWINGOUTLONDON_SECRET_TOKEN="ba66a824fff6ff0ea2d8..."
In order to use the twitter gem you'll need to register your app and set the twitter api keys in your environment.
% export TWITTER_CONSUMER_KEY="..."
% export TWITTER_CONSUMER_SECRET="..."
% export TWITTER_OAUTH_TOKEN="..."
% export TWITTER_OAUTH_TOKEN_SECRET="..."
As above, you'll also need to set these in your deployment environment