jsonpathng

Jsonpathng is a library that provides support for the JSONPath query language, enabling developers to extract and manipulate data from JSON documents. It offers a simple API for evaluating path expressions against a JSON data structure and returning the matched elements as a collection.

Key features commonly associated with jsonpathng include support for root and path notation using symbols such as the dollar sign, dot notation, and bracket notation. It typically implements wildcards, recursive descent, array indices and ranges, and filter expressions. Path expressions can select single values or multiple matches, depending on the query. In many implementations, missing matches yield an empty result set rather than errors, though behavior can be configurable.

Usage patterns usually involve either a direct extraction function that accepts a JSON object and a path, or a two-step approach that compiles a path expression into an executable object for reuse. The library is designed to work with native JSON data structures in the host language, aiming for a lightweight footprint and minimal dependencies.

Return values are generally represented in native data types such as numbers, strings, booleans, and nulls, which facilitates integration into data processing pipelines, templates, and testing workflows. Performance considerations often emphasize efficient traversal and low memory overhead for large or deeply nested JSON documents.

In practice, jsonpathng serves as a tool for querying and transforming JSON data without manual traversal, complementing data extraction, reporting, and validation tasks. Related concepts include the JSONPath standard and other language-specific implementations of JSONPath.