The ACME issuer type supports an optional 'webhook' solver, which can be used to implement custom DNS01 challenge solving logic.
This is useful if you need to use cert-manager with a DNS provider that is not officially supported in cert-manager core - as in this case with do.de (Domain-Offensive)
As the project & adoption has grown, there has been an influx of DNS provider pull requests to our core codebase. As this number has grown, the test matrix has become un-maintainable and so, it's not possible for us to certify that providers work to a sufficient level.
By creating this 'interface' between cert-manager and DNS providers, we allow users to quickly iterate and test out new integrations, and then packaging those up themselves as 'extensions' to cert-manager.
We can also then provide a standardised 'testing framework', or set of conformance tests, which allow us to validate that a DNS provider works as expected.
All DNS providers must run the DNS01 provider conformance testing suite, else they will have undetermined behaviour when used with cert-manager.
It is essential that you configure and run the test suite when creating a DNS01 webhook.
In order to successfully run the tests with this webhook you need a valid token and a domain registered under you account.
You can run the test suite with:
$ TEST_ZONE_NAME=yourdomain.tld. make test