Comment by georgecalm

If you'd like to use something like this in your own APIs to let your clients filter requests or on the CLI (as is the intention with gron), consider giving "json-mask" a try (you'll need Node.js installed):

  $ echo '{"user": {"name": "Sam", "age": 40}}' | npx json-mask "user/age"
  {"user":{"age":40}}

or (from the first gron example; the results are identical)

  $ gron "https://api.github.com/repos/tomnomnom/gron/commits?per_page=1" | fgrep "commit.author" | gron --ungron
  $ curl "https://api.github.com/repos/tomnomnom/gron/commits?per_page=1" | npx json-mask "commit/author"

If you've ever used Google APIs' `fields=` query param you already know how to use json-mask; it's super simple:

  a,b,c - comma-separated list will select multiple fields
  a/b/c - path will select a field from its parent
  a(b,c) - sub-selection will select many fields from a parent
  a/*/c - the star * wildcard will select all items in a field