fix(Webhook Node): Do not create binary data when there is no data in the request (#8000)

https://linear.app/n8n/issue/NODE-980/do-not-create-binary-data-for-webhooks-when-there-is-no-data-in-the

related:
https://github.com/n8n-io/n8n/pull/7804/files#r1422641833

---------

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

packages/nodes-base/nodes/Webhook/Webhook.node.ts

@@ -1,6 +1,7 @@
 /* eslint-disable n8n-nodes-base/node-execute-block-wrong-error-thrown */
 import { pipeline } from 'stream/promises';
 import { createWriteStream } from 'fs';
+import { stat } from 'fs/promises';
 import type {
 	IWebhookFunctions,
 	ICredentialDataDecryptedObject,
@@ -216,7 +217,6 @@ export class Webhook extends Node {
 		const { data, files } = req.body;
 
 		const returnItem: INodeExecutionData = {
-			binary: {},
 			json: {
 				headers: req.headers,
 				params: req.params,
@@ -225,6 +225,10 @@ export class Webhook extends Node {
 			},
 		};
 
+		if (files?.length) {
+			returnItem.binary = {};
+		}
+
 		let count = 0;
 
 		for (const key of Object.keys(files)) {
@@ -274,7 +278,6 @@ export class Webhook extends Node {
 			await pipeline(req, createWriteStream(binaryFile.path));
 
 			const returnItem: INodeExecutionData = {
-				binary: {},
 				json: {
 					headers: req.headers,
 					params: req.params,
@@ -283,20 +286,18 @@ export class Webhook extends Node {
 				},
 			};
 
-			const binaryPropertyName = (options.binaryPropertyName || 'data') as string;
+			const stats = await stat(binaryFile.path);
+			if (stats.size) {
+				const binaryPropertyName = (options.binaryPropertyName ?? 'data') as string;
 				const fileName = req.contentDisposition?.filename ?? uuid();
 				const binaryData = await context.nodeHelpers.copyBinaryFile(
 					binaryFile.path,
 					fileName,
 					req.contentType ?? 'application/octet-stream',
 				);
-
+				returnItem.binary = { [binaryPropertyName]: binaryData };
-			if (!binaryData.data) {
-				return { workflowData: [[returnItem]] };
 			}
 
-			returnItem.binary![binaryPropertyName] = binaryData;
-
 			return { workflowData: [[returnItem]] };
 		} catch (error) {
 			throw new NodeOperationError(context.getNode(), error as Error);