fix(core): Make runner disconnected error more user-friendly (no-changelog) (#11829)

Co-authored-by: Iván Ovejero <ivov.src@gmail.com>

packages/cli/src/runners/default-task-runner-disconnect-analyzer.ts

@@ -12,6 +12,10 @@ import type { DisconnectAnalyzer, DisconnectErrorOptions } from './runner-types'
  */
 @Service()
 export class DefaultTaskRunnerDisconnectAnalyzer implements DisconnectAnalyzer {
+	get isCloudDeployment() {
+		return config.get('deployment.type') === 'cloud';
+	}
+
 	async toDisconnectError(opts: DisconnectErrorOptions): Promise<Error> {
 		const { reason, heartbeatInterval } = opts;
 
@@ -22,6 +26,9 @@ export class DefaultTaskRunnerDisconnectAnalyzer implements DisconnectAnalyzer {
 			);
 		}
 
-		return new TaskRunnerDisconnectedError(opts.runnerId ?? 'Unknown runner ID');
+		return new TaskRunnerDisconnectedError(
+			opts.runnerId ?? 'Unknown runner ID',
+			this.isCloudDeployment,
+		);
 	}
 }

packages/cli/src/runners/errors/__tests__/task-runner-disconnected-error.test.ts

@@ -0,0 +1,49 @@
+import { TaskRunnerDisconnectedError } from '../task-runner-disconnected-error';
+
+describe('TaskRunnerDisconnectedError', () => {
+	it('should have the correct default error message', () => {
+		const error = new TaskRunnerDisconnectedError('test-runner-id', false);
+
+		expect(error.message).toBe('Node execution failed');
+	});
+
+	it('should have the error level set to "error"', () => {
+		const error = new TaskRunnerDisconnectedError('test-runner-id', false);
+
+		expect(error.level).toBe('error');
+	});
+
+	it('should set the correct description for non-cloud deployments', () => {
+		const error = new TaskRunnerDisconnectedError('test-runner-id', false);
+
+		expect(error.description).toContain(
+			'This can happen for various reasons. Please try executing the node again.',
+		);
+		expect(error.description).toContain(
+			'1. Reduce the number of items processed at a time, by batching them using a loop node',
+		);
+		expect(error.description).toContain(
+			"2. Increase the memory available to the task runner with 'N8N_RUNNERS_MAX_OLD_SPACE_SIZE' environment variable",
+		);
+		expect(error.description).not.toContain(
+			'Upgrade your cloud plan to increase the available memory',
+		);
+	});
+
+	it('should set the correct description for cloud deployments', () => {
+		const error = new TaskRunnerDisconnectedError('test-runner-id', true);
+
+		expect(error.description).toContain(
+			'This can happen for various reasons. Please try executing the node again.',
+		);
+		expect(error.description).toContain(
+			'1. Reduce the number of items processed at a time, by batching them using a loop node',
+		);
+		expect(error.description).toContain(
+			'2. Upgrade your cloud plan to increase the available memory',
+		);
+		expect(error.description).not.toContain(
+			"Increase the memory available to the task runner with 'N8N_RUNNERS_MAX_OLD_SPACE_SIZE' environment variable",
+		);
+	});
+});

packages/cli/src/runners/errors/task-runner-disconnected-error.ts

@@ -1,7 +1,34 @@
+import type { TaskRunner } from '@n8n/task-runner';
 import { ApplicationError } from 'n8n-workflow';
 
 export class TaskRunnerDisconnectedError extends ApplicationError {
-	constructor(runnerId: string) {
-		super(`Task runner (${runnerId}) disconnected`);
+	public description: string;
+
+	constructor(
+		public readonly runnerId: TaskRunner['id'],
+		isCloudDeployment: boolean,
+	) {
+		super('Node execution failed');
+
+		const fixSuggestions = {
+			reduceItems:
+				'Reduce the number of items processed at a time, by batching them using a loop node',
+			increaseMemory:
+				"Increase the memory available to the task runner with 'N8N_RUNNERS_MAX_OLD_SPACE_SIZE' environment variable",
+			upgradePlan: 'Upgrade your cloud plan to increase the available memory',
+		};
+
+		const subtitle =
+			'This can happen for various reasons. Please try executing the node again. If the problem persists, you can try the following:';
+		const suggestions = isCloudDeployment
+			? [fixSuggestions.reduceItems, fixSuggestions.upgradePlan]
+			: [fixSuggestions.reduceItems, fixSuggestions.increaseMemory];
+		const suggestionsText = suggestions
+			.map((suggestion, index) => `${index + 1}. ${suggestion}`)
+			.join('<br/>');
+
+		const description = `${subtitle}<br/><br/>${suggestionsText}`;
+
+		this.description = description;
 	}
 }

packages/cli/src/runners/internal-task-runner-disconnect-analyzer.ts

@@ -1,8 +1,6 @@
 import { TaskRunnersConfig } from '@n8n/config';
 import { Service } from 'typedi';
 
-import config from '@/config';
-
 import { DefaultTaskRunnerDisconnectAnalyzer } from './default-task-runner-disconnect-analyzer';
 import { TaskRunnerOomError } from './errors/task-runner-oom-error';
 import type { DisconnectErrorOptions } from './runner-types';
@@ -16,10 +14,6 @@ import { TaskRunnerProcess } from './task-runner-process';
  */
 @Service()
 export class InternalTaskRunnerDisconnectAnalyzer extends DefaultTaskRunnerDisconnectAnalyzer {
-	private get isCloudDeployment() {
-		return config.get('deployment.type') === 'cloud';
-	}
-
 	private readonly exitReasonSignal: SlidingWindowSignal<TaskRunnerProcessEventMap, 'exit'>;
 
 	constructor(

packages/cli/src/runners/runner-types.ts

@@ -6,6 +6,8 @@ import type { TaskRunner } from './task-broker.service';
 import type { AuthlessRequest } from '../requests';
 
 export interface DisconnectAnalyzer {
+	isCloudDeployment: boolean;
+
 	toDisconnectError(opts: DisconnectErrorOptions): Promise<Error>;
 }