I have a web app that sends users to an offsite payment server to complete a transaction, and I'm working on the PHP page that users are returned to upon completion of the transaction. The script uses a lot of variables that are set by the external server, and I'm wondering what are the best practices for testing my script without having to actually go through doing a live transaction.
Do I include a file that sets all those variables to dummy values? Or just set those variables at the beginning of the script? (And then hopefully remember to remove this stuff before putting the script on production.)