fix(core): Support redis cluster in queue mode (#6708)

* support redis cluster

* cleanup, fix config schema

* set default prefix to bull

packages/cli/src/AbstractServer.ts

@@ -10,7 +10,7 @@ import parseUrl from 'parseurl';
 import type { RedisOptions } from 'ioredis';
 
 import type { WebhookHttpMethod } from 'n8n-workflow';
-import { LoggerProxy as Logger } from 'n8n-workflow';
+import { LoggerProxy } from 'n8n-workflow';
 import config from '@/config';
 import { N8N_VERSION, inDevelopment } from '@/constants';
 import { ActiveWorkflowRunner } from '@/ActiveWorkflowRunner';
@@ -27,6 +27,7 @@ import { corsMiddleware } from '@/middlewares';
 import { TestWebhooks } from '@/TestWebhooks';
 import { WaitingWebhooks } from '@/WaitingWebhooks';
 import { WEBHOOK_METHODS } from '@/WebhookHelpers';
+import { getRedisClusterNodes } from './GenericHelpers';
 
 const emptyBuffer = Buffer.alloc(0);
 
@@ -187,42 +188,64 @@ export abstract class AbstractServer {
 		let lastTimer = 0;
 		let cumulativeTimeout = 0;
 		const { host, port, username, password, db }: RedisOptions = config.getEnv('queue.bull.redis');
+		const clusterNodes = getRedisClusterNodes();
 		const redisConnectionTimeoutLimit = config.getEnv('queue.bull.redis.timeoutThreshold');
-
-		const redis = new Redis({
-			host,
-			port,
-			db,
+		const usesRedisCluster = clusterNodes.length > 0;
+		LoggerProxy.debug(
+			usesRedisCluster
+				? `Initialising Redis cluster connection with nodes: ${clusterNodes
+						.map((e) => `${e.host}:${e.port}`)
+						.join(',')}`
+				: `Initialising Redis client connection with host: ${host ?? 'localhost'} and port: ${
+						port ?? '6379'
+				  }`,
+		);
+		const sharedRedisOptions: RedisOptions = {
 			username,
 			password,
-			retryStrategy: (): number | null => {
-				const now = Date.now();
-				if (now - lastTimer > 30000) {
-					// Means we had no timeout at all or last timeout was temporary and we recovered
-					lastTimer = now;
-					cumulativeTimeout = 0;
-				} else {
-					cumulativeTimeout += now - lastTimer;
-					lastTimer = now;
-					if (cumulativeTimeout > redisConnectionTimeoutLimit) {
-						Logger.error(
-							`Unable to connect to Redis after ${redisConnectionTimeoutLimit}. Exiting process.`,
-						);
-						process.exit(1);
-					}
-				}
-				return 500;
-			},
-		});
+			db,
+			enableReadyCheck: false,
+			maxRetriesPerRequest: null,
+		};
+		const redis = usesRedisCluster
+			? new Redis.Cluster(
+					clusterNodes.map((node) => ({ host: node.host, port: node.port })),
+					{
+						redisOptions: sharedRedisOptions,
+					},
+			  )
+			: new Redis({
+					host,
+					port,
+					...sharedRedisOptions,
+					retryStrategy: (): number | null => {
+						const now = Date.now();
+						if (now - lastTimer > 30000) {
+							// Means we had no timeout at all or last timeout was temporary and we recovered
+							lastTimer = now;
+							cumulativeTimeout = 0;
+						} else {
+							cumulativeTimeout += now - lastTimer;
+							lastTimer = now;
+							if (cumulativeTimeout > redisConnectionTimeoutLimit) {
+								LoggerProxy.error(
+									`Unable to connect to Redis after ${redisConnectionTimeoutLimit}. Exiting process.`,
+								);
+								process.exit(1);
+							}
+						}
+						return 500;
+					},
+			  });
 
 		redis.on('close', () => {
-			Logger.warn('Redis unavailable - trying to reconnect...');
+			LoggerProxy.warn('Redis unavailable - trying to reconnect...');
 		});
 
 		redis.on('error', (error) => {
 			if (!String(error).includes('ECONNREFUSED')) {
 				// eslint-disable-next-line @typescript-eslint/no-unsafe-argument
-				Logger.warn('Error with Redis: ', error);
+				LoggerProxy.warn('Error with Redis: ', error);
 			}
 		});
 	}

packages/cli/src/GenericHelpers.ts

@@ -199,4 +199,28 @@ export async function createErrorExecution(
 	await Container.get(ExecutionRepository).createNewExecution(fullExecutionData);
 }
 
+export function getRedisClusterNodes(): Array<{ host: string; port: number }> {
+	const clusterNodePairs = config
+		.getEnv('queue.bull.redis.clusterNodes')
+		.split(',')
+		.filter((e) => e);
+	return clusterNodePairs.map((pair) => {
+		const [host, port] = pair.split(':');
+		return { host, port: parseInt(port) };
+	});
+}
+
+export function getRedisPrefix(): string {
+	let prefix = config.getEnv('queue.bull.prefix');
+	if (prefix && getRedisClusterNodes().length > 0) {
+		if (!prefix.startsWith('{')) {
+			prefix = '{' + prefix;
+		}
+		if (!prefix.endsWith('}')) {
+			prefix += '}';
+		}
+	}
+	return prefix;
+}
+
 export const DEFAULT_EXECUTIONS_GET_ALL_LIMIT = 20;

packages/cli/src/Queue.ts

@@ -1,10 +1,11 @@
 import type Bull from 'bull';
-import type { RedisOptions } from 'ioredis';
+import { type RedisOptions } from 'ioredis';
 import { Service } from 'typedi';
-import type { IExecuteResponsePromiseData } from 'n8n-workflow';
+import { LoggerProxy, type IExecuteResponsePromiseData } from 'n8n-workflow';
 import config from '@/config';
 import { ActiveExecutions } from '@/ActiveExecutions';
 import * as WebhookHelpers from '@/WebhookHelpers';
+import { getRedisClusterNodes, getRedisPrefix } from './GenericHelpers';
 
 export type JobId = Bull.JobId;
 export type Job = Bull.Job<JobData>;
@@ -31,19 +32,54 @@ export class Queue {
 	constructor(private activeExecutions: ActiveExecutions) {}
 
 	async init() {
-		const prefix = config.getEnv('queue.bull.prefix');
-		const redisOptions: RedisOptions = config.getEnv('queue.bull.redis');
-
+		const prefix = getRedisPrefix();
+		const clusterNodes = getRedisClusterNodes();
+		const usesRedisCluster = clusterNodes.length > 0;
+		const { host, port, username, password, db }: RedisOptions = config.getEnv('queue.bull.redis');
 		// eslint-disable-next-line @typescript-eslint/naming-convention
 		const { default: Bull } = await import('bull');
-
+		// eslint-disable-next-line @typescript-eslint/naming-convention
+		const { default: Redis } = await import('ioredis');
 		// Disabling ready check is necessary as it allows worker to
 		// quickly reconnect to Redis if Redis crashes or is unreachable
 		// for some time. With it enabled, worker might take minutes to realize
 		// redis is back up and resume working.
 		// More here: https://github.com/OptimalBits/bull/issues/890
-		// @ts-ignore
-		this.jobQueue = new Bull('jobs', { prefix, redis: redisOptions, enableReadyCheck: false });
+
+		LoggerProxy.debug(
+			usesRedisCluster
+				? `Initialising Redis cluster connection with nodes: ${clusterNodes
+						.map((e) => `${e.host}:${e.port}`)
+						.join(',')}`
+				: `Initialising Redis client connection with host: ${host ?? 'localhost'} and port: ${
+						port ?? '6379'
+				  }`,
+		);
+		const sharedRedisOptions: RedisOptions = {
+			username,
+			password,
+			db,
+			enableReadyCheck: false,
+			maxRetriesPerRequest: null,
+		};
+		this.jobQueue = new Bull('jobs', {
+			prefix,
+			createClient: (type, clientConfig) =>
+				usesRedisCluster
+					? new Redis.Cluster(
+							clusterNodes.map((node) => ({ host: node.host, port: node.port })),
+							{
+								...clientConfig,
+								redisOptions: sharedRedisOptions,
+							},
+					  )
+					: new Redis({
+							...clientConfig,
+							host,
+							port,
+							...sharedRedisOptions,
+					  }),
+		});
 
 		this.jobQueue.on('global:progress', (jobId, progress: WebhookResponse) => {
 			this.activeExecutions.resolveResponsePromise(

packages/cli/src/config/schema.ts

@@ -353,9 +353,9 @@ export const schema = {
 		},
 		bull: {
 			prefix: {
-				doc: 'Prefix for all queue keys',
+				doc: 'Prefix for all queue keys (wrap in {} for cluster mode)',
 				format: String,
-				default: '',
+				default: 'bull',
 				env: 'QUEUE_BULL_PREFIX',
 			},
 			redis: {
@@ -395,6 +395,12 @@ export const schema = {
 					default: '',
 					env: 'QUEUE_BULL_REDIS_USERNAME',
 				},
+				clusterNodes: {
+					doc: 'Redis Cluster startup nodes (comma separated list of host:port pairs)',
+					format: String,
+					default: '',
+					env: 'QUEUE_BULL_REDIS_CLUSTER_NODES',
+				},
 			},
 			queueRecoveryInterval: {
 				doc: 'If > 0 enables an active polling to the queue that can recover for Redis crashes. Given in seconds; 0 is disabled. May increase Redis traffic significantly.',