@full-dress-10026 function in

transformation

receives given yaml string already parsed to JS object. given your yaml string, it should look like this:

{
  "apiVersion": "v1",
  "kind": "ConfigMap",
  "metadata": {
    "name": "honeycomb-agent-config",
    "namespace": "default"
  },
  "data": {
    "config.yaml": "# By default, submit logs from interesting system pods such as the\n# kube DNS\nwatchers:\n  - dataset: kubernetes-logs\n    labelSelector: \"k8s-app=aws-node\"\n    namespace: kube-system\n    parser: glog\n  - dataset: kubernetes-logs\n    labelSelector: \"k8s-app=kube-proxy\"\n    namespace: kube-system\n    parser: glog\n  - dataset: kubernetes-logs\n    labelSelector: \"k8s-app=kube-dns\"\n    namespace: kube-system\n    parser: glog\nverbosity: info\n# splitLogging directs trace, debug, info, and warn log levels to stdout\n# rather than stderr.\nsplitLogging: false"
  }
}

therefore, you need to

JSON.parse(manifest.data["config.yaml"])

, modify the object as you need, and

JSON.stringify()

it back to

manifest.data["config.yaml"]