Hi, this is part of our work to support the `valkey_client` relation for the 12-factor extensions. This PR comes as a pair with https://github.com/canonical/paas-charm/pull/282. As we're using `dpcharmlibs.interfaces`, the library can be added as a dependency of `paas-charm`. Therefore, the only changes necessary on `charmcraft`'s side is the init template with the optional relation declaration and documentation of the expected environment variables. Describe your changes. --- - [x] I've followed the [contribution guidelines](https://github.com/canonical/charmcraft/blob/main/CONTRIBUTING.md). - [x] I've signed the [CLA](http://www.ubuntu.com/legal/contributors/). - [x] I've successfully run `make lint && make test`. - [x] I've added or updated any relevant documentation. - [ ] In documents I changed, I [added a meta description](https://canonical-starflow.readthedocs-hosted.com/how-to/add-a-page-meta-description/) if one was missing. - [ ] I've updated the relevant release notes.