Even though this app was well intended, we've realised that it's not actually
required. AWS Route53 supports multi-level wildcard records. In plain English,
if *.cf-hero.cloudcredo.io is resolved, all subdomains, regardless of level,
will resolve to the same endpoints, e.g.:
$ dig +noall +answer baz.cf-hero.cloudcredo.io
baz.cf-hero.cloudcredo.io. 300 IN A 54.175.58.208
baz.cf-hero.cloudcredo.io. 300 IN A 52.20.111.137
$ dig +noall +answer bar.baz.cf-hero.cloudcredo.io
bar.baz.cf-hero.cloudcredo.io. 300 IN A 52.20.111.137
bar.baz.cf-hero.cloudcredo.io. 300 IN A 54.175.58.208
$ dig +noall +answer foo.bar.baz.cf-hero.cloudcredo.io
foo.bar.baz.cf-hero.cloudcredo.io. 300 IN A 54.175.58.208
foo.bar.baz.cf-hero.cloudcredo.io. 300 IN A 52.20.111.137
We've also learned that when a new record gets registered, it takes a few minutes for it to propagate, even to the uber popular Google's Public DNS resolution service.
In conclusion, we've avoided all the extra hassle associated with any new code and manually resolved the wildcard record.
A web app to enable Cloud Foundry for Beginners: Zero to Hero trainees to integrate a custom domain with their Cloud Foundry app.
The app itself talks to the AWS Route53 API to register custom subdomains.
Once registered, they will be used by the trainees e.g.
cf add-domain cf-hero gerhard.cf-hero.cloudcredo.io for their own apps.
All registered subdomains are listed on the web app's index page.