refactor(core): Show deprecation warning if task runners are disabled (#13189)

packages/cli/src/deprecation/__tests__/deprecation.service.test.ts

@@ -3,13 +3,13 @@ import { mockLogger } from '@test/mocking';
 import { DeprecationService } from '../deprecation.service';
 
 describe('DeprecationService', () => {
-	const toTest = (envVar: string, value: string, inUse: boolean) => {
+	const toTest = (envVar: string, value: string, mustWarn: boolean) => {
 		process.env[envVar] = value;
 		const deprecationService = new DeprecationService(mockLogger());
 
 		deprecationService.warn();
 
-		expect(deprecationService.isInUse(envVar)).toBe(inUse);
+		expect(deprecationService.mustWarn(envVar)).toBe(mustWarn);
 	};
 
 	test.each([
@@ -18,16 +18,16 @@ describe('DeprecationService', () => {
 		['EXECUTIONS_DATA_PRUNE_TIMEOUT', '1', true],
 		['N8N_CONFIG_FILES', '1', true],
 		['N8N_SKIP_WEBHOOK_DEREGISTRATION_SHUTDOWN', '1', true],
-	])('should detect when %s is in use', (envVar, value, inUse) => {
+	])('should detect when %s is in use', (envVar, value, mustWarn) => {
-		toTest(envVar, value, inUse);
+		toTest(envVar, value, mustWarn);
 	});
 
 	test.each([
 		['default', true],
 		['filesystem', false],
 		['s3', false],
-	])('should handle N8N_BINARY_DATA_MODE as %s', (mode, inUse) => {
+	])('should handle N8N_BINARY_DATA_MODE as %s', (mode, mustWarn) => {
-		toTest('N8N_BINARY_DATA_MODE', mode, inUse);
+		toTest('N8N_BINARY_DATA_MODE', mode, mustWarn);
 	});
 
 	test.each([
@@ -35,7 +35,28 @@ describe('DeprecationService', () => {
 		['postgresdb', false],
 		['mysqldb', true],
 		['mariadb', true],
-	])('should handle DB_TYPE as %s', (dbType, inUse) => {
+	])('should handle DB_TYPE as %s', (dbType, mustWarn) => {
-		toTest('DB_TYPE', dbType, inUse);
+		toTest('DB_TYPE', dbType, mustWarn);
+	});
+
+	describe('N8N_RUNNERS_ENABLED', () => {
+		const envVar = 'N8N_RUNNERS_ENABLED';
+
+		test.each([
+			['false', true],
+			['', true],
+			['true', false],
+			[undefined /* warnIfMissing */, true],
+		])('should handle value: %s', (value, mustWarn) => {
+			if (value === undefined) {
+				delete process.env[envVar];
+			} else {
+				process.env[envVar] = value;
+			}
+
+			const deprecationService = new DeprecationService(mockLogger());
+			deprecationService.warn();
+			expect(deprecationService.mustWarn(envVar)).toBe(mustWarn);
+		});
 	});
 });

packages/cli/src/deprecation/deprecation.service.ts

@@ -12,12 +12,15 @@ type Deprecation = {
 	message: string;
 
 	/** Function to identify the specific value in the env var that is deprecated. */
-	checkValue?: (value: string) => boolean;
+	checkValue?: (value?: string) => boolean;
+
+	/** Whether to show a deprecation warning if the env var is missing. */
+	warnIfMissing?: boolean;
 };
 
 const SAFE_TO_REMOVE = 'Remove this environment variable; it is no longer needed.';
 
-/** Responsible for warning about use of deprecated env vars. */
+/** Responsible for warning about deprecations related to env vars. */
 @Service()
 export class DeprecationService {
 	private readonly deprecations: Deprecation[] = [
@@ -39,10 +42,17 @@ export class DeprecationService {
 			envVar: 'N8N_SKIP_WEBHOOK_DEREGISTRATION_SHUTDOWN',
 			message: `n8n no longer deregisters webhooks at startup and shutdown. ${SAFE_TO_REMOVE}`,
 		},
+		{
+			envVar: 'N8N_RUNNERS_ENABLED',
+			message:
+				'Running n8n without task runners is deprecated. Task runners will be turned on by default in a future version. Please set `N8N_RUNNERS_ENABLED=true` to enable task runners now and avoid potential issues in the future. Learn more: https://docs.n8n.io/hosting/configuration/task-runners/',
+			checkValue: (value?: string) => value?.toLowerCase() !== 'true' && value !== '1',
+			warnIfMissing: true,
+		},
 	];
 
-	/** Runtime state of deprecated env vars. */
+	/** Runtime state of deprecation-related env vars. */
-	private readonly state: Record<EnvVarName, { inUse: boolean }> = {};
+	private readonly state: Record<EnvVarName, { mustWarn: boolean }> = {};
 
 	constructor(private readonly logger: Logger) {}
 
@@ -50,14 +60,14 @@ export class DeprecationService {
 		this.deprecations.forEach((d) => {
 			const envValue = process.env[d.envVar];
 			this.state[d.envVar] = {
-				inUse: d.checkValue
+				mustWarn:
-					? envValue !== undefined && d.checkValue(envValue)
+					(d.warnIfMissing !== undefined && envValue === undefined) ||
-					: envValue !== undefined,
+					(d.checkValue ? d.checkValue(envValue) : envValue !== undefined),
 			};
 		});
 
-		const inUse = Object.entries(this.state)
+		const mustWarn = Object.entries(this.state)
-			.filter(([, d]) => d.inUse)
+			.filter(([, d]) => d.mustWarn)
 			.map(([envVar]) => {
 				const deprecation = this.deprecations.find((d) => d.envVar === envVar);
 				if (!deprecation) {
@@ -66,19 +76,19 @@ export class DeprecationService {
 				return deprecation;
 			});
 
-		if (inUse.length === 0) return;
+		if (mustWarn.length === 0) return;
 
-		const header = `The following environment variable${
+		const header = `There ${
-			inUse.length === 1 ? ' is' : 's are'
+			mustWarn.length === 1 ? 'is a deprecation' : 'are deprecations'
-		} deprecated and will be removed in an upcoming version of n8n. Please take the recommended actions to update your configuration`;
+		} related to your environment variables. Please take the recommended actions to update your configuration`;
-		const deprecations = inUse
+		const deprecations = mustWarn
 			.map(({ envVar, message }) => ` - ${envVar} -> ${message}\n`)
 			.join('');
 
 		this.logger.warn(`\n${header}:\n${deprecations}`);
 	}
 
-	isInUse(envVar: string) {
+	mustWarn(envVar: string) {
-		return this.state[envVar]?.inUse ?? false;
+		return this.state[envVar]?.mustWarn ?? false;
 	}
 }