How can I set a Heroku dyno config var dynamically, such as the REDIS_URL, based on the current url for that addon?

Question

I added heroku-redis as an addon to one of my dynos and it states that the URI for the redis instance can change. The URI for that instance is set as a config var in my dyno. Is there any way to set that config var to automatically update if/when the URI for the redis instance changes?

Fumbled through documentation and searched through stackoverflow.

Answer 1

Solution found. When on the free tier, you must set and manage the value yourself. When on a paid tier, the config var is auto-created and auto-updated.