Support to generate ResourceDistribution with configmap/secret

[hantmac]

BackGround

For the scenario, where the namespace-scoped resources such as Secret and ConfigMap need to be distributed or synchronized to different namespaces, the native k8s currently only supports manual distribution and synchronization by users one-by-one, which is very inconvenient. So OpenKruise provide a resource called ResourceDistribution to manage these resources.

But k8s support apply -f to any resources include ResourceDistribution. But you know configmap or secret usually import from a file in yaml and keep it's format may be difficult. So kubectl kruise should support to create a RescourceDistribution with a configmap/secret according a file easily.

How to do

There are two ways: 1. kustomize generator plugin, 2. kubectl kruise cmd

kustomize generator plugin

Kustomize offers a plugin framework allowing people to write their own resource generators and transformers. More details in this doc. So we can implement a generator plugin for kruise workload.

kubectl kruise implement the cmd

The defect of kustomize plugin is inconvenient to use. User has to add the plugin to target directory. So we can also implement the same generator logic in kubectl kruise like:

kubectl kruise create resourcedistribution ResourceDistributionName --targetObject=configmap --targetNamespace=test --from-file=configure-pod-container/configmap