[Question] Reggex based node selection from the JSON

[manikyab]

I want select nodes based on a starting pattern. Can you please help me with the JSON PATH?

I am new to RFC9535 and JSON path

Thanks
Manikya

[jarangutan]

JsonPath includes a match and search function extension to help filter on arrays that allows regular expressions.

See this match query $..book[?match(@.category, "^r.*")] where ^r.* is a regular expression that looks for the starting character "r" followed by whatever.

Link to query in playground
Link to match function extension

Or see this search query $..book[?search(@.category, "^r")] where it does a substring search looking for the starting character to be "r"

Link to query in playground
Link to search function extension

[manikyab]

{ "CH_name": "Channel 1", "CH_id": 123, "status": "active" }
In the above JSON, I want to select all the elements which have keys starting with CH_
Every where it mentions I should use @property but I am unable to get results based on it.
My query is $[?search(@, "^CH_")]
@jarangutan thanks for the prompt reply

[theory]

@property is an extension of JSONPath not supported by RFC-9535. It does, however, support function extensions, provided in this implementation by the registry package. Alas, it only supports validation of values, not the selectors for those values.

I've thought for a while it might be useful to provide an implementation that passes the selector to a function, as well as the value. That would allow the function to examine the selector (in your case, an object property name) and return true only for those that start with CH_. The spec doesn't say anything about what can or should be passed to function extensions, so I think it would be okay. I should ask the authors. If they go for it, it would likely not be too much work to implement.

[manikyab]

I think it would be a great added feature because there are many use cases where we wanted to find a node which fits the certain rules.