Is there a json path filtering everything having a specific value?

Question

I'm trying my hands at a, kind of, templating mechanism for JSON.

I have this reduced example JSON template

{
        "type": "AdaptiveCard",
        "body": [
            {
                "type": "Container",
                "isVisible": "$._has_content.success",
                "items": [
                    {
                        "type": "TextBlock",
                        "text": "$.result[0].text",
                    },
                    {
                        "type": "FactSet",
                        "facts": [
                            "$.success.*"
                        ]
                    }
                ]
            },
            {
                "type": "Container",
                "style": "attention",
                "isVisible": "$._has_content.fail",
                "items": [
                    {
                        "type": "TextBlock",
                        "text": "Failures",
                    },
                    {
                        "type": "FactSet",
                        "facts": [
                            "$.fail.*"
                        ]
                    }
                ]
            }
        ],
    }

I now need to filter all those nodes where a value starts with "$".

So these should be found:

        $.body[0].isVisible
        $.body[0].items[0].text
        $.body[0].items[1].facts
        $.body[1].isVisible
        $.body[1].items[1].facts

I just started with JSON Path and have not found a way to define a proper filter.

My attempts like $.body..*[?(@.* =~ /^\$./)] failed.

Update: Additionally to the answer by @gregsdennis, I found, thanks to his reply, the correct syntax I should have used: $..[?(@ =~ /^[$]/)]

Answer 1

Not all JSON Path implementation support regex, however the official JSON Path spec (just released!) does define match() (implicit anchors) and search() (explicit anchors) regex processing.

Since this is a newly released specification, it's likely not many implementations conform yet. However, mine does, and you can play with it at https://json-everything.net/json-path.

So if you use $.body..*[?search(@, '^\\$.*')], you'll get the results you're looking for:

[
  {
    "Value": "$._has_content.success",
    "Location": "$['body'][0]['isVisible']"
  },
  {
    "Value": "$._has_content.fail",
    "Location": "$['body'][1]['isVisible']"
  },
  {
    "Value": "$.result[0].text",
    "Location": "$['body'][0]['items'][0]['text']"
  },
  {
    "Value": "$.success.*",
    "Location": "$['body'][0]['items'][1]['facts'][0]"
  },
  {
    "Value": "$.fail.*",
    "Location": "$['body'][1]['items'][1]['facts'][0]"
  }
]

which includes the value and location for every node.

Note that the escape \ needs to be doubled because it's in a string literal (JSON escaping rules).

I recommend contacting the implementation maintainers to see what their library supports.