Circular Safe Json Stringfy

circular-safe-json-stringfy.ts

type JsonLike = {
	[key: string]: string | number | undefined | null | JsonLike;
};

const getCircularReplacer = () => {
	const seen = new WeakSet();

	return (_, value: JsonLike) => {
		if (typeof value === 'object' && value !== null) {
			if (seen.has(value)) {
				return;
			}
			seen.add(value);
		}

		return value;
	};
};

const safeStringify = (data: JsonLike) =>
	JSON.stringify(data, getCircularReplacer());

const example: JsonLike = {
	data1: 1,
};

example.data2 = example;

console.log('Original JSON', example);

/**
 * {
 *    data1: 1,
 *    data2: { data1: 1, data2: ... }
 * }
 */

console.log(safeStringify(example));

/**
 * {
 *    "data1": 1
 * }
 */


// Credits:
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Cyclic_object_value#examples