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Is it possible to perform node operations like add labels, drain, cordon, etc. I'm not seeing it in the Api documentation at all.

Add label:

let nodes: Api<Node> = Api::all(client);
nodes
    .patch(
        "name",
        &PatchParams::default(),
        &Patch::Merge(serde_json::json!({ "metadata": { "labels": { "app": "example" } } })),
    )
    .await?;

Cordon should be:

let nodes: Api<Node> = Api::all(client);
nodes
    .patch(
        "name",
        &PatchParams::default(),
        &Patch::Merge(serde_json::json!({ "spec": { "unschedulable": true } })),
    )
    .await?;

Drain should be cordon + evicting all pods in it.

You can use kubectl with --v=9 to find the API requests.

We can probably add convenience methods like in https://github.com/kube-rs/kube-rs/pull/635/files for cordon/uncordon.

Yeah, even in client-go operations like drain and cordon are not among its core verbs. These "operations" are just kubectl helpers: cordon.go + drain.go

I'm ok with having drain + cordon as utility helpers or examples (as a start). We support the eviction subresource (Api::evict) necessary for this. If you would like to try writing a drainer example or a utility fn for Drain then that would be welcome - i'd be happy to help.

#762 now adds Api<Node>::cordon and Api<Node>::uncordon thanks to @ChinYing-Li :tada:

The only thing left here is an example for Api<Node>::drain. As it stands currently herein, this is non-trivial to unit-test / integration test an Api<Node>::drain fn since it probably requires a real node, with real pods, to be created and drained. I think it's OK for this to be done in an example for now. But am open to suggestions. kubectl does have some fairly verbose tests for drain - no idea how fast or sensible these are yet.