JSON Pathfinder

JSON Pathfinder is a javascript library dedicated to finding the line number for a given JSONPath query in a json string

Installation

Use the package manager npm to install json-pathfinder.

npm -i @jeanbono/json-pathfinder

Usage

import { jsonPathfinder } from '@jeanbono/json-pathfinder';

const jsonString = '{\n\
    "foo": "bar",\n\
    "baz": [{ \n\
        "hello": "world" \n\
    }]\n\
}';

// parse the json string
const pathfinder = jsonPathfinder(jsonString);

// returns line number 4
console.log(pathfinder('$.baz[0].hello'));

Path syntax

Queries follow RFC 9535 (JSONPath), restricted to singular queries — the root identifier $ followed by member-name and array-index segments. Wildcards, slices, filters, and descendant selectors aren't supported, since they can match more than one location and this library always resolves to exactly one line.

Both forms below are accepted and resolve to the same result — bracket notation is required for member names that aren't valid identifiers (containing a literal ., [, whitespace, ...):

pathfinder('$.baz[0].hello');
pathfinder("$['baz'][0]['hello']");

A syntactically invalid query throws; a valid query with no matching location returns -1.

Note: versions before 2.0.0 used a bare a.b[0].c syntax without a leading $. Prefix existing queries with $. (or switch to bracket notation) to upgrade.

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

License

ISC