fix(core): Restore body parsing for all content-types for non webhook routes (no-changelog)(#6911)

Changes in https://github.com/n8n-io/n8n/pull/6394 removed xml body parsing for all non-webhook routes. This broken SAML endpoints as they need the XML body parser to function correctly.

packages/cli/src/AbstractServer.ts

@@ -11,7 +11,7 @@ import { N8nInstanceType } from '@/Interfaces';
 import type { IExternalHooksClass } from '@/Interfaces';
 import { ExternalHooks } from '@/ExternalHooks';
 import { send, sendErrorResponse, ServiceUnavailableError } from '@/ResponseHelper';
-import { rawBody, jsonParser, corsMiddleware } from '@/middlewares';
+import { rawBodyReader, bodyParser, corsMiddleware } from '@/middlewares';
 import { TestWebhooks } from '@/TestWebhooks';
 import { WaitingWebhooks } from '@/WaitingWebhooks';
 import { webhookRequestHandler } from '@/WebhookHelpers';
@@ -98,7 +98,7 @@ export abstract class AbstractServer {
 		this.app.use(compression());
 
 		// Read incoming data into `rawBody`
-		this.app.use(rawBody);
+		this.app.use(rawBodyReader);
 	}
 
 	private setupDevMiddlewares() {
@@ -274,8 +274,8 @@ export abstract class AbstractServer {
 			this.setupDevMiddlewares();
 		}
 
-		// Setup JSON parsing middleware after the webhook handlers are setup
-		this.app.use(jsonParser);
+		// Setup body parsing middleware after the webhook handlers are setup
+		this.app.use(bodyParser);
 
 		await this.configure();
 

packages/cli/src/WebhookHelpers.ts

@@ -12,8 +12,6 @@ import { Container } from 'typedi';
 import get from 'lodash/get';
 import stream from 'stream';
 import { promisify } from 'util';
-import { parse as parseQueryString } from 'querystring';
-import { Parser as XmlParser } from 'xml2js';
 import formidable from 'formidable';
 
 import { BinaryDataManager, NodeExecuteFunctions } from 'n8n-core';
@@ -40,7 +38,6 @@ import {
 	BINARY_ENCODING,
 	createDeferredPromise,
 	ErrorReporterProxy as ErrorReporter,
-	jsonParse,
 	LoggerProxy as Logger,
 	NodeHelpers,
 } from 'n8n-workflow';
@@ -64,6 +61,7 @@ import type { User } from '@db/entities/User';
 import type { WorkflowEntity } from '@db/entities/WorkflowEntity';
 import { EventsService } from '@/services/events.service';
 import { OwnershipService } from './services/ownership.service';
+import { parseBody } from './middlewares';
 
 const pipeline = promisify(stream.pipeline);
 
@@ -76,13 +74,6 @@ export const WEBHOOK_METHODS: IHttpRequestMethods[] = [
 	'PUT',
 ];
 
-const xmlParser = new XmlParser({
-	async: true,
-	normalize: true, // Trim whitespace inside text nodes
-	normalizeTags: true, // Transform tags to lowercase
-	explicitArray: false, // Only put properties in array if length > 1
-});
-
 export const webhookRequestHandler =
 	(webhookManager: IWebhookManager) =>
 	async (req: WebhookRequest | WebhookCORSRequest, res: express.Response) => {
@@ -316,28 +307,7 @@ export async function executeWebhook(
 					});
 				});
 			} else {
-				await req.readRawBody();
-				const { rawBody } = req;
-				if (rawBody?.length) {
-					try {
-						if (contentType === 'application/json') {
-							req.body = jsonParse(rawBody.toString(encoding));
-						} else if (contentType?.endsWith('/xml') || contentType?.endsWith('+xml')) {
-							req.body = await xmlParser.parseStringPromise(rawBody.toString(encoding));
-						} else if (contentType === 'application/x-www-form-urlencoded') {
-							req.body = parseQueryString(rawBody.toString(encoding), undefined, undefined, {
-								maxKeys: 1000,
-							});
-						} else if (contentType === 'text/plain') {
-							req.body = rawBody.toString(encoding);
-						}
-					} catch (error) {
-						throw new ResponseHelper.UnprocessableRequestError(
-							'Failed to parse request body',
-							error.message,
-						);
-					}
-				}
+				await parseBody(req);
 			}
 		}
 

packages/cli/src/middlewares/bodyParser.ts

@@ -1,12 +1,22 @@
 import { parse as parseContentDisposition } from 'content-disposition';
 import { parse as parseContentType } from 'content-type';
 import getRawBody from 'raw-body';
-import { type RequestHandler } from 'express';
+import type { Request, RequestHandler } from 'express';
+import { parse as parseQueryString } from 'querystring';
+import { Parser as XmlParser } from 'xml2js';
 import { jsonParse } from 'n8n-workflow';
 import config from '@/config';
+import { UnprocessableRequestError } from '@/ResponseHelper';
+
+const xmlParser = new XmlParser({
+	async: true,
+	normalize: true, // Trim whitespace inside text nodes
+	normalizeTags: true, // Transform tags to lowercase
+	explicitArray: false, // Only put properties in array if length > 1
+});
 
 const payloadSizeMax = config.getEnv('endpoints.payloadSizeMax');
-export const rawBody: RequestHandler = async (req, res, next) => {
+export const rawBodyReader: RequestHandler = async (req, res, next) => {
 	if ('content-type' in req.headers) {
 		const { type: contentType, parameters } = (() => {
 			try {
@@ -41,21 +51,32 @@ export const rawBody: RequestHandler = async (req, res, next) => {
 	next();
 };
 
-export const jsonParser: RequestHandler = async (req, res, next) => {
+export const parseBody = async (req: Request) => {
 	await req.readRawBody();
-
-	if (Buffer.isBuffer(req.rawBody)) {
-		if (req.contentType === 'application/json') {
-			try {
-				req.body = jsonParse<unknown>(req.rawBody.toString(req.encoding));
-			} catch (error) {
-				res.status(400).send({ error: 'Failed to parse request body' });
-				return;
+	const { rawBody, contentType, encoding } = req;
+	if (rawBody?.length) {
+		try {
+			if (contentType === 'application/json') {
+				// eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+				req.body = jsonParse(rawBody.toString(encoding));
+			} else if (contentType?.endsWith('/xml') || contentType?.endsWith('+xml')) {
+				// eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+				req.body = await xmlParser.parseStringPromise(rawBody.toString(encoding));
+			} else if (contentType === 'application/x-www-form-urlencoded') {
+				req.body = parseQueryString(rawBody.toString(encoding), undefined, undefined, {
+					maxKeys: 1000,
+				});
+			} else if (contentType === 'text/plain') {
+				req.body = rawBody.toString(encoding);
 			}
-		} else {
-			req.body = {};
+		} catch (error) {
+			throw new UnprocessableRequestError('Failed to parse request body', (error as Error).message);
 		}
 	}
+};
 
+export const bodyParser: RequestHandler = async (req, res, next) => {
+	await parseBody(req);
+	if (!req.body) req.body = {};
 	next();
 };

packages/cli/test/integration/shared/utils/testServer.ts

@@ -30,7 +30,7 @@ import {
 	TagsController,
 	UsersController,
 } from '@/controllers';
-import { rawBody, jsonParser, setupAuthMiddlewares } from '@/middlewares';
+import { rawBodyReader, bodyParser, setupAuthMiddlewares } from '@/middlewares';
 
 import { InternalHooks } from '@/InternalHooks';
 import { LoadNodesAndCredentials } from '@/LoadNodesAndCredentials';
@@ -118,7 +118,7 @@ export const setupTestServer = ({
 	enabledFeatures,
 }: SetupProps): TestServer => {
 	const app = express();
-	app.use(rawBody);
+	app.use(rawBodyReader);
 	app.use(cookieParser());
 
 	const testServer: TestServer = {
@@ -153,7 +153,7 @@ export const setupTestServer = ({
 
 		if (!endpointGroups) return;
 
-		app.use(jsonParser);
+		app.use(bodyParser);
 
 		const [routerEndpoints, functionEndpoints] = classifyEndpointGroups(endpointGroups);