Kubernetes v1.34: Use An Init Container To Define App Environment Variables

Kubernetes typically uses ConfigMaps and Secrets to set environment variables, which introduces additional API calls and complexity, For example, you need to separately manage the Pods of your workloads and their configurations, while ensuring orderly updates for both the configurations and the workload Pods. Alternatively, you might be using a vendor-supplied container that requires environment variables (such as a license key or a one-time token), but you don’t want to hard-code them or mount volumes just to get the job done. If that's the situation you are in, you now have a new (alpha) way to achieve that. Provided you have the EnvFiles feature gate enabled across your cluster, you can tell the kubelet to load a container's environment variables from a volume (the volume must be part of the Pod that the container belongs to). this feature gate allows you to load environment variables directly from a file in an emptyDir volume without actually mounting that file into the container.