directus/api/src/utils/redact.ts

import type { UnknownObject } from '@directus/types';
import { isObject } from '@directus/utils';

type Paths = string[][];

/**
 * Redact values at certain paths in an object.
 * @param input Input object in which values should be redacted.
 * @param paths Nested array of object paths to be redacted (supports `*` for shallow matching, `**` for deep matching).
 * @param replacement Replacement the values are redacted by.
 * @returns Redacted object.
 */
export function redact(input: UnknownObject, paths: Paths, replacement: string): UnknownObject {
	const wildcardChars = ['*', '**'];

	const clone = JSON.parse(JSON.stringify(input, errorReplacer));
	const visited = new WeakSet<UnknownObject>();
	traverse(clone, paths);

	return clone;

	function traverse(object: UnknownObject, checkPaths: Paths): void {
		if (checkPaths.length === 0) {
			return;
		}

		visited.add(object);

		const globalCheckPaths = [];

		for (const key of Object.keys(object)) {
			const localCheckPaths = [];

			for (const [index, path] of [...checkPaths].entries()) {
				const [current, ...remaining] = path;

				const escapedKey = wildcardChars.includes(key) ? `\\${key}` : key;

				switch (current) {
					case escapedKey:
						if (remaining.length > 0) {
							localCheckPaths.push(remaining);
						} else {
							object[key] = replacement;
							checkPaths.splice(index, 1);
						}

						break;
					case '*':
						if (remaining.length > 0) {
							globalCheckPaths.push(remaining);
							checkPaths.splice(index, 1);
						} else {
							object[key] = replacement;
						}

						break;
					case '**':
						if (remaining.length > 0) {
							const [next, ...nextRemaining] = remaining;

							if (next === escapedKey) {
								if (nextRemaining.length === 0) {
									object[key] = replacement;
								} else {
									localCheckPaths.push(nextRemaining);
								}
							} else if (next !== undefined && wildcardChars.includes(next)) {
								localCheckPaths.push(remaining);
							} else {
								localCheckPaths.push(path);
							}
						} else {
							object[key] = replacement;
						}

						break;
				}
			}

			const value = object[key];

			if (isObject(value) && !visited.has(value)) {
				traverse(value, [...globalCheckPaths, ...localCheckPaths]);
			}
		}
	}
}

/**
 * Extract values from Error objects for use with JSON.stringify()
 */
export function errorReplacer(_key: string, value: unknown) {
	if (value instanceof Error) {
		return {
			name: value.name,
			message: value.message,
			stack: value.stack,
			cause: value.cause,
		};
	}

	return value;
}