BotFramework-Composer: Missing way to extract only the keys from a JSON object

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

I use [Send an HTTP request] feature to call an external REST API, which returns a JSON object that looks like this:

{
  "sheepdog": [
    "english",
    "shetland"
  ],
  "shiba": [],
  "spaniel": [
    "blenheim",
    "brittany",
    "cocker",
    "irish",
    "japanese",
    "sussex",
    "welsh"
  ]
}

I would like to get an array containing only the keys from this JSON result and let the user select it, but I can’t find such a function in the adaptive expressions and can’t achieve it. In the above example, I want to enumerate only seepdog, shiba, and spaniel.

Actually, you can try it with the following open source API.

https://dog.ceo/api/breeds/list/all

Describe the solution you’d like

It seems to be possible to handle this by creating a custom action, but I’d like to achieve it without writing code.