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kubernetesjqjsonpathyq

Print keys in yaml, so that they can be used for jsonpath

echo "apiVersion: v1
kind: Node
metadata:
  name: host-cluster-control-plane-64j47
  labels:
    beta.kubernetes.io/arch: amd64
" | yq -o p

Result:

apiVersion = v1
kind = Node
metadata.name = host-cluster-control-plane-64j47
metadata.labels.beta.kubernetes.io/arch = amd64

That's almost what I want. I am looking for the key to get values.

I could use metadata.name like this:

echo "apiVersion: v1
kind: Node
metadata:
  name: host-cluster-control-plane-64j47
  labels:
    beta.kubernetes.io/arch: amd64
" | yq '.metadata.name'

But the -o p option of yq does not quote the key, if needed.

I can't use metadata.labels.beta.kubernetes.io/arch as key, since the correct syntax is metadata.labels["beta.kubernetes.io/arch"].

Is there an automated way to get the keys of a yaml file so that I can use the keys in yq (or jq)?

The desired output would be something like this:

apiVersion = v1
kind = Node
metadata.name = host-cluster-control-plane-64j47
metadata.labels["beta.kubernetes.io/arch"] = amd64

I am looking for the valid key, because I want to create a second command line to select these values.

For example:

❯ k get nodes -o yaml | yq '.items[].metadata.labels["beta.kubernetes.io/arch"]'

amd64
amd64
amd64
Solution

  • You can get close by doing something like:

    yq '(.. | key | select(test("\."))) |= ("[\"" + . + "\"]")' file.yaml -op

apiVersion = v1
kind = Node
metadata.name = host-cluster-control-plane-64j47
metadata.labels.["beta.kubernetes.io/arch"] = amd64

    Or you could do:

    yq '(.. | key | select(test("\."))) |= sub("\.", "\.")' file.yaml -op

apiVersion = v1
kind = Node
metadata.name = host-cluster-control-plane-64j47
metadata.labels.beta\\.kubernetes\\.io/arch = amd64

    BTW - I'm not sure how it's supposed be escaped in property files, I'd be willing to update yq to do it natively someone raises a bug with details on github...

    Disclaimer: I wrote yq