Returning a Javascript file through Laravel

I am looking to return a Javascript file when a customer goes to a specific URL on my Laravel development. I will run a check against a DB table before showing the Javascript file;

1. User visits http://ift.tt/2dnrL54
2. Laravel checks against the DB to see if 123542 exists as an account
3. If it exists then return javascript.js if not return error.

The javascript file will be the same no matter what URL is requested so I just need to return a JS file.

I just need to know how to return the Javascript file.

via Chebli Mohamed