Robust Top-Level JSON Extractor

Overview

This library only extracts all highest-level valid JSON objects from noisy or malformed text streams. It is designed to handle input where JSON objects may be embedded in extra braces, log headers, or partially malformed data, while still guaranteeing that extracted objects are parseable by JSON.parse.

This package is meant to be used with payloads under 1MB with somewhat reasonably shaped JSON data, as worst-case time complexity is O(n^3), despite pruning techniques.

Features

• Extracts multiple valid top-level JSON objects from a single string.
• Ignores unmatched braces, extra characters, or malformed sections.
• Works with escaped quotes inside JSON strings.
• Returns list of jsons derived from original input.

Installation

npm install full-json-extractor

Usage

import { extractJsons } from 'full-json-extractor';

const rawString = `[log header] { "id": 1, "data": { "key": "value" } } more text`;
const jsonObjects = extractJsons(rawString);

console.log(jsonObjects);
// Output: [{ id: 1, data: { key: 'value' } }]

API

extractJsons(input: string, limit: Limit = "none"): object[]

Wrapper for Internal BFS/memoization routine to find all valid JSON intervals.