Reloader VS keda

You can combine this approach with something like https://github.com/stakater/Reloader to automatically restart pods when a certain secret value changes. So if your static code needs to be rebuilt when certain values change, you can use an init container to run the build on startup.

This is not a cron job? I'm not sure if it helps, but you can have pods do a rolling restart on secret updates: https://github.com/stakater/Reloader that would clear the resources each run, but I'm not entirely clear on what you're looking to achieve.

If you use secrets as Environment Variables you will need to use something to make workloads get the new credentials, if they just loose connection. You can use the Reloader project for that.

Reloader is designed to simplify the process of updating application configurations in Kubernetes. It monitors ConfigMaps and Secrets for changes and triggers rolling upgrades for associated resources such as Deployments, StatefulSets, DaemonSets, and more. Reloader eliminates the need for manual intervention and reduces the risk of errors during the configuration update process.

The go k8s packages are pretty bloated - this may also just be a niche case. If you are looking to get secrets with hot reloading, you might also consider mounting a file or setting env vars and coupling it with this reloading operator: https://github.com/stakater/Reloader

For the auto restart this has been a staple install in all clusters for years for me: https://github.com/stakater/Reloader

If you didn't want to use SOPS, for some reason, you can certainly take advantage of external secrets as another commenter proposed, but you won't be able to accomplish (2) without an external tool adding to the mix, like Reloader: https://github.com/stakater/Reloader – that's because something has to update the HelmRelease in order to trigger it to upgrade. (You could just wait for the reconciler to come along, but the tendency is to set the polling interval longer than the default, so Helm won't be re-trying as often, in case something goes wrong...)

You can install https://github.com/stakater/Reloader And then it's just matter of a single annotation and it restarts automatically when there are changes.

It seems you want something like KEDA (https://keda.sh)

Most just utilize out of the box macro resources available in HPA.

For more advanced use cases there is keda - https://keda.sh/

Thankfully KEDA operator was already part of the cluster, and all Robin had to do was create a ScaledObject manifest targeting the Dispatch ScaleUp event, based on the rabbitmq_global_messages_received_total metric from Prometheus.

Keda

KEDA introduces event-driven scaling to Kubernetes workloads. It integrates with Kubernetes Horizontal Pod Autoscalers and can scale pods based on external metrics from services like databases and message queues (Kafka, RabbitMQ, MongoDB).

# update version 2.8.2 if required kubectl apply -f https://github.com/kedacore/keda/releases/download/v2.8.2/keda-2.8.2.yaml

This is traditionally a AWS Lambda usecase - or an OpenFaas kind of usecase. But very recently i discovered https://keda.sh/ and it seems it is specifically meant for this in a kubernetes environment.

If you deploy the application to Amazon EKS, you can also consider using KEDA to auto-scale your consumer application based on the number of messages in the MSK topic.