Support kubernetes filter use_kubelet feature

[erdody]

Is your feature request related to a problem? Please describe.

For people that want to use the use_kubelet feature, fluent-operator is not an option.

Describe the solution you'd like

Add support for use_kubelet, adding it to the CRD, in addition with the related config properties

Additional context

No response

[Cajga]

Seems this can be done already if one manually deploys the operator. We are deploying through helm and it seems it would be quite complex to achieve everything through that. Part of this can be done already by the operator helm chart through values (namely, enabling hostnetwork and changing the dnsPolicy).

It is also passible to pass the useKubelet, kubeletHost, kubeletPort values like fluentbit.filter.kubernetes.useKubelet=true etc.

So, only one part is missing:

1. RBAC modification: the CRD supports adding it through rbacRules but the helm chart does not support it yet.

@benjaminhuo , would you guys accept a pull request on the helm chart template to achieve this?

[benjaminhuo]

Seems this can be done already if one manually deploys the operator. We are deploying through helm and it seems it would be quite complex to achieve everything through that. Part of this can be done already by the operator helm chart through values (namely, enabling hostnetwork and changing the dnsPolicy).

It is also passible to pass the useKubelet, kubeletHost, kubeletPort values like fluentbit.filter.kubernetes.useKubelet=true etc.

So, only one part is missing:

1. RBAC modification: the CRD supports adding it through rbacRules but the helm chart does not support it yet.

@benjaminhuo , would you guys accept a pull request on the helm chart template to achieve this?

Yes, of course. @Cajga It'll be great if you can create a PR with some docs elaborating how to add useKubelet