feat(core): Cancel runner task on timeout in external mode

docker/images/n8n/n8n-task-runners.json

@@ -12,6 +12,7 @@
 				"N8N_RUNNERS_TASK_BROKER_URI",
 				"N8N_RUNNERS_MAX_PAYLOAD",
 				"N8N_RUNNERS_MAX_CONCURRENCY",
+				"N8N_RUNNERS_TASK_TIMEOUT",
 				"N8N_RUNNERS_HEALTH_CHECK_SERVER_ENABLED",
 				"N8N_RUNNERS_HEALTH_CHECK_SERVER_HOST",
 				"N8N_RUNNERS_HEALTH_CHECK_SERVER_PORT",

packages/@n8n/config/src/configs/runners.config.ts

@@ -43,11 +43,11 @@ export class TaskRunnersConfig {
 	@Env('N8N_RUNNERS_MAX_CONCURRENCY')
 	maxConcurrency: number = 5;
 
-	/** How long (in seconds) a task is allowed to take for completion, else the task will be aborted and the runner restarted. Must be greater than 0. */
+	/** How long (in seconds) a task is allowed to take for completion, else the task will be aborted. (In internal mode, the runner will also be restarted.) Must be greater than 0. */
 	@Env('N8N_RUNNERS_TASK_TIMEOUT')
 	taskTimeout: number = 60;
 
-	/** How often (in seconds) the runner must send a heartbeat to the broker, else the task will be aborted and the runner restarted. Must be greater than 0. */
+	/** How often (in seconds) the runner must send a heartbeat to the broker, else the task will be aborted. (In internal mode, the runner will also  be restarted.) Must be greater than 0. */
 	@Env('N8N_RUNNERS_HEARTBEAT_INTERVAL')
 	heartbeatInterval: number = 30;
 }

packages/@n8n/task-runner/src/config/base-runner-config.ts

@@ -37,6 +37,9 @@ export class BaseRunnerConfig {
 	@Env('GENERIC_TIMEZONE')
 	timezone: string = 'America/New_York';
 
+	@Env('N8N_RUNNERS_TASK_TIMEOUT')
+	taskTimeout: number = 60;
+
 	@Nested
 	healthcheckServer!: HealthcheckServerConfig;
 }

packages/@n8n/task-runner/src/js-task-runner/__tests__/js-task-runner.test.ts

@@ -1,3 +1,4 @@
+import { mock } from 'jest-mock-extended';
 import { DateTime } from 'luxon';
 import { setGlobalState, type CodeExecutionMode, type IDataObject } from 'n8n-workflow';
 import fs from 'node:fs';
@@ -61,7 +62,7 @@ describe('JsTaskRunner', () => {
 		runner?: JsTaskRunner;
 	}) => {
 		jest.spyOn(runner, 'requestData').mockResolvedValue(taskData);
-		return await runner.executeTask(task);
+		return await runner.executeTask(task, mock<AbortSignal>());
 	};
 
 	afterEach(() => {

packages/@n8n/task-runner/src/js-task-runner/__tests__/task-runner.test.ts

@@ -21,6 +21,7 @@ describe('TestRunner', () => {
 				maxPayloadSize: 1024,
 				taskBrokerUri: 'http://localhost:8080',
 				timezone: 'America/New_York',
+				taskTimeout: 60,
 				healthcheckServer: {
 					enabled: false,
 					host: 'localhost',
@@ -48,6 +49,7 @@ describe('TestRunner', () => {
 				maxPayloadSize: 1024,
 				taskBrokerUri: 'https://example.com:3000/path',
 				timezone: 'America/New_York',
+				taskTimeout: 60,
 				healthcheckServer: {
 					enabled: false,
 					host: 'localhost',
@@ -77,6 +79,7 @@ describe('TestRunner', () => {
 						maxPayloadSize: 1024,
 						taskBrokerUri: 'not-a-valid-uri',
 						timezone: 'America/New_York',
+						taskTimeout: 60,
 						healthcheckServer: {
 							enabled: false,
 							host: 'localhost',
@@ -86,4 +89,65 @@ describe('TestRunner', () => {
 			).toThrowError(/Invalid URL/);
 		});
 	});
+
+	describe('taskCancelled', () => {
+		it('should reject pending requests when task is cancelled', () => {
+			const runner = new TestRunner({
+				taskType: 'test-task',
+				maxConcurrency: 5,
+				idleTimeout: 60,
+				grantToken: 'test-token',
+				maxPayloadSize: 1024,
+				taskBrokerUri: 'http://localhost:8080',
+				timezone: 'America/New_York',
+				taskTimeout: 60,
+				healthcheckServer: {
+					enabled: false,
+					host: 'localhost',
+					port: 8081,
+				},
+			});
+
+			const taskId = 'test-task';
+			runner.runningTasks.set(taskId, {
+				taskId,
+				active: false,
+				cancelled: false,
+			});
+
+			const dataRequestReject = jest.fn();
+			const nodeTypesRequestReject = jest.fn();
+
+			runner.dataRequests.set('data-req', {
+				taskId,
+				requestId: 'data-req',
+				resolve: jest.fn(),
+				reject: dataRequestReject,
+			});
+
+			runner.nodeTypesRequests.set('node-req', {
+				taskId,
+				requestId: 'node-req',
+				resolve: jest.fn(),
+				reject: nodeTypesRequestReject,
+			});
+
+			runner.taskCancelled(taskId, 'test-reason');
+
+			expect(dataRequestReject).toHaveBeenCalledWith(
+				expect.objectContaining({
+					message: 'Task cancelled: test-reason',
+				}),
+			);
+
+			expect(nodeTypesRequestReject).toHaveBeenCalledWith(
+				expect.objectContaining({
+					message: 'Task cancelled: test-reason',
+				}),
+			);
+
+			expect(runner.dataRequests.size).toBe(0);
+			expect(runner.nodeTypesRequests.size).toBe(0);
+		});
+	});
 });

packages/@n8n/task-runner/src/js-task-runner/errors/task-cancelled-error.ts

@@ -0,0 +1,7 @@
+import { ApplicationError } from 'n8n-workflow';
+
+export class TaskCancelledError extends ApplicationError {
+	constructor(reason: string) {
+		super(`Task cancelled: ${reason}`, { level: 'warning' });
+	}
+}

packages/@n8n/task-runner/src/js-task-runner/errors/timeout-error.ts

@@ -0,0 +1,30 @@
+import { ApplicationError } from 'n8n-workflow';
+
+export class TimeoutError extends ApplicationError {
+	description: string;
+
+	constructor(taskTimeout: number) {
+		super(
+			`Task execution timed out after ${taskTimeout} ${taskTimeout === 1 ? 'second' : 'seconds'}`,
+		);
+
+		const subtitle = 'The task runner was taking too long on this task, so the task was aborted.';
+
+		const fixes = {
+			optimizeScript:
+				'Optimize your script to prevent long-running tasks, e.g. by processing data in smaller batches.',
+			ensureTermination:
+				'Ensure that all paths in your script are able to terminate, i.e. no infinite loops.',
+		};
+
+		const suggestions = [fixes.optimizeScript, fixes.ensureTermination];
+
+		const suggestionsText = suggestions
+			.map((suggestion, index) => `${index + 1}. ${suggestion}`)
+			.join('<br/>');
+
+		const description = `${subtitle} You can try the following:<br/><br/>${suggestionsText}`;
+
+		this.description = description;
+	}
+}

packages/@n8n/task-runner/src/js-task-runner/js-task-runner.ts

@@ -32,6 +32,7 @@ import { BuiltInsParserState } from './built-ins-parser/built-ins-parser-state';
 import { isErrorLike } from './errors/error-like';
 import { ExecutionError } from './errors/execution-error';
 import { makeSerializable } from './errors/serializable-error';
+import { TimeoutError } from './errors/timeout-error';
 import type { RequireResolver } from './require-resolver';
 import { createRequireResolver } from './require-resolver';
 import { validateRunForAllItemsOutput, validateRunForEachItemOutput } from './result-validation';
@@ -94,7 +95,7 @@ export class JsTaskRunner extends TaskRunner {
 		});
 	}
 
-	async executeTask(task: Task<JSExecSettings>): Promise<TaskResultData> {
+	async executeTask(task: Task<JSExecSettings>, signal: AbortSignal): Promise<TaskResultData> {
 		const settings = task.settings;
 		a.ok(settings, 'JS Code not sent to runner');
 
@@ -133,8 +134,8 @@ export class JsTaskRunner extends TaskRunner {
 
 		const result =
 			settings.nodeMode === 'runOnceForAllItems'
-				? await this.runForAllItems(task.taskId, settings, data, workflow, customConsole)
-				: await this.runForEachItem(task.taskId, settings, data, workflow, customConsole);
+				? await this.runForAllItems(task.taskId, settings, data, workflow, customConsole, signal)
+				: await this.runForEachItem(task.taskId, settings, data, workflow, customConsole, signal);
 
 		return {
 			result,
@@ -183,6 +184,7 @@ export class JsTaskRunner extends TaskRunner {
 		data: JsTaskData,
 		workflow: Workflow,
 		customConsole: CustomConsole,
+		signal: AbortSignal,
 	): Promise<INodeExecutionData[]> {
 		const dataProxy = this.createDataProxy(data, workflow, data.itemIndex);
 		const inputItems = data.connectionInputData;
@@ -199,10 +201,26 @@ export class JsTaskRunner extends TaskRunner {
 		};
 
 		try {
-			const result = (await runInNewContext(
-				`globalThis.global = globalThis; module.exports = async function VmCodeWrapper() {${settings.code}\n}()`,
-				context,
-			)) as TaskResultData['result'];
+			const result = await new Promise<TaskResultData['result']>((resolve, reject) => {
+				const abortHandler = () => {
+					reject(new TimeoutError(this.taskTimeout));
+				};
+
+				signal.addEventListener('abort', abortHandler, { once: true });
+
+				const taskResult = runInNewContext(
+					`globalThis.global = globalThis; module.exports = async function VmCodeWrapper() {${settings.code}\n}()`,
+					context,
+					{ timeout: this.taskTimeout * 1000 },
+				) as Promise<TaskResultData['result']>;
+
+				void taskResult
+					.then(resolve)
+					.catch(reject)
+					.finally(() => {
+						signal.removeEventListener('abort', abortHandler);
+					});
+			});
 
 			if (result === null) {
 				return [];
@@ -230,6 +248,7 @@ export class JsTaskRunner extends TaskRunner {
 		data: JsTaskData,
 		workflow: Workflow,
 		customConsole: CustomConsole,
+		signal: AbortSignal,
 	): Promise<INodeExecutionData[]> {
 		const inputItems = data.connectionInputData;
 		const returnData: INodeExecutionData[] = [];
@@ -255,10 +274,26 @@ export class JsTaskRunner extends TaskRunner {
 			};
 
 			try {
-				let result = (await runInNewContext(
-					`module.exports = async function VmCodeWrapper() {${settings.code}\n}()`,
-					context,
-				)) as INodeExecutionData | undefined;
+				let result = await new Promise<INodeExecutionData | undefined>((resolve, reject) => {
+					const abortHandler = () => {
+						reject(new TimeoutError(this.taskTimeout));
+					};
+
+					signal.addEventListener('abort', abortHandler);
+
+					const taskResult = runInNewContext(
+						`module.exports = async function VmCodeWrapper() {${settings.code}\n}()`,
+						context,
+						{ timeout: this.taskTimeout * 1000 },
+					) as Promise<INodeExecutionData>;
+
+					void taskResult
+						.then(resolve)
+						.catch(reject)
+						.finally(() => {
+							signal.removeEventListener('abort', abortHandler);
+						});
+				});
 
 				// Filter out null values
 				if (result === null) {