On: Parsing JSON at the CLI: A Practical Introduction ...

[donut]

Agreed, gron is a fantastic tool.

Earler today I was looking at some deeply nested structures which had leaf nodes with a field named "fileURL", and values that were mostly "https://" but some were "http://". I needed to see how many, etc.

cat file.json | gron | grep fileURL | grep http | grep -v https

... and presto, I had only four such nodes.

Would've been a ton more work to get there with just jq.

[Arnavion → donut]

Based on your description, it sounds like:

    <file.json jq '.. | .fileURL? | select(startswith("http://"))' -r

... would've done the job?

Or, if you can't remember `startswith`:

    <file.json jq '.. | .fileURL?' -r | grep '^http://'

[donut → Arnavion]

Nice and terse :-)

Right, the ".." part was hard to remember because it's something like:

  {
    "entries": [
      {
        "fields": {
          "fileURL": {
            "en-US": "https://..."
          },
          ...
        },
        ...
      },
      ...
    ]
  }

and as you can see the field fileURL is actually an object with another field en-US (with a hyphen) so the jq becomes something like this:

<file.json jq -r '.entries[] | .fields | select(.fileURL) | .fileURL["en-US"] | select(startswith("http://"))'

And later I had to do the same for other fields that ended in URL (websiteURL, etc.)

Anyway, gron made it simpler to get a quick summary of what I needed because it represents every node in the tree as a separate line that has the path in it, which is perfect for grep.

I still use jq more than gron :-)

[Arnavion → donut]

>Right, the ".." part was hard to remember because it's something like:

You misunderstand. The command I wrote is meant to be used as I wrote it. `..` is not a placeholder for you to replace.

https://stedolan.github.io/jq/manual/#RecursiveDescent%3a%2e...

>and as you can see the field fileURL is actually an object with another field en-US (with a hyphen) so the jq becomes something like this:

Sure, so then it's:

    <file.json jq '.. | select(.fileURL?).fileURL["en-US"] | select(startswith("http://"))' -r

[donut → Arnavion]

Oh, I had no idea ".." was an operator. That's a pretty cool feature, combined with the "?" to match optional objects.

Thanks for explaining!