fix(core): Remove circular refs from Code and push msg (#5741)

* remove circular refs from code items (and lint fixes)

* cleanup

---------

* add some tests

Co-authored-by: कारतोफ्फेलस्क्रिप्ट™ <aditya@netroy.in>

packages/workflow/src/index.ts

@@ -23,7 +23,7 @@ export * from './WorkflowErrors';
 export * from './WorkflowHooks';
 export * from './VersionedNodeType';
 export { LoggerProxy, NodeHelpers, ObservableObject, TelemetryHelpers };
-export { deepCopy, jsonParse, sleep, fileTypeFromMimeType, assert } from './utils';
+export { deepCopy, jsonParse, jsonStringify, sleep, fileTypeFromMimeType, assert } from './utils';
 export {
 	isINodeProperties,
 	isINodePropertyOptions,

packages/workflow/src/utils.ts

@@ -62,6 +62,31 @@ export const jsonParse = <T>(jsonString: string, options?: JSONParseOptions<T>):
 	}
 };
 
+type JSONStringifyOptions = {
+	replaceCircularRefs?: boolean;
+	circularRefReplacement?: string;
+};
+
+const getReplaceCircularReferencesFn = (options: JSONStringifyOptions) => {
+	const knownObjects = new WeakSet();
+	return (key: any, value: any) => {
+		if (typeof value === 'object' && value !== null) {
+			if (knownObjects.has(value)) {
+				return options?.circularRefReplacement ?? '[Circular Reference]';
+			}
+			knownObjects.add(value);
+		}
+		return value;
+	};
+};
+
+export const jsonStringify = (obj: unknown, options: JSONStringifyOptions = {}): string => {
+	const replacer = options?.replaceCircularRefs
+		? getReplaceCircularReferencesFn(options)
+		: undefined;
+	return JSON.stringify(obj, replacer);
+};
+
 export const sleep = async (ms: number): Promise<void> =>
 	new Promise((resolve) => {
 		setTimeout(resolve, ms);

packages/workflow/test/utils.test.ts

@@ -1,4 +1,4 @@
-import { jsonParse, deepCopy } from '@/utils';
+import { jsonParse, jsonStringify, deepCopy } from '@/utils';
 
 describe('jsonParse', () => {
 	it('parses JSON', () => {
@@ -17,6 +17,21 @@ describe('jsonParse', () => {
 	});
 });
 
+describe('jsonStringify', () => {
+	const source: any = { a: 1, b: 2 };
+	source.c = source;
+
+	it('should throw errors on circular references by default', () => {
+		expect(() => jsonStringify(source)).toThrow('Converting circular structure to JSON');
+	});
+
+	it('should break circular references when requested', () => {
+		expect(jsonStringify(source, { replaceCircularRefs: true })).toEqual(
+			'{"a":1,"b":2,"c":"[Circular Reference]"}',
+		);
+	});
+});
+
 describe('deepCopy', () => {
 	it('should deep copy an object', () => {
 		const serializable = {