TrafficRouterPlugins - lazy initialisation of canary resources

[mgs255]

Hi

I've been playing around with rollouts in combination with Linkerd to try to implement a very gradual canary process. I was planning to extend the existing Gateway API plugin for this purpose. In our case, we have something like 150 different workloads, most of which follow a standard pattern for the services and ports exposed. This seems to work well when I create the required objects before the rollout is started.

Ideally, I'd have liked the plugin to be able to create the required K8S objects lazily when the rollout is initiated if they don't exist. Ie the Canary's Service and the HTTPRoute object. I was planning on using the stable service as the template for the canary object and simply changing the name. The plugin would also need to take care of cleaning up after itself when the rollout completes.

I was hoping to extend the UpdateHash method for this purpose, however, this approach doesn't appear to be possible currently as the the controller is complaining about missing canary resources so it never gets as far as the plugin. Is such an approach possible or sensible. Possibly I've just missed something obvious.

Thanks a lot.