https://operatorhub.io/ and "operator framework" (can't find the link to a readme) are the only things that really make sense here. Don't write them from scratch.
Basic idea is that you write a process that monitors your deployment, that reacts to config changes and events. You might end up thinking "Isn't that what kubernetes should be doing already" if you are not addicted to jumping on year-old hype trains. But if you want to do k8s that's the only way to really go. Forget all the other stuff of managing deployments if it doesn't integrate with your operator strategy.
Basic idea is that you write a process that monitors your deployment, that reacts to config changes and events. You might end up thinking "Isn't that what kubernetes should be doing already" if you are not addicted to jumping on year-old hype trains. But if you want to do k8s that's the only way to really go. Forget all the other stuff of managing deployments if it doesn't integrate with your operator strategy.