feat(core): Make Redis available for backend communication (#6719)

* support redis cluster

* cleanup, fix config schema

* set default prefix to bull

* initial commit

* improve logging

* improve types and refactor

* list support and refactor

* fix redis service and tests

* add comment

* add redis and cache prefix

* use injection

* lint fix

* clean schema comments

* improve naming, tests, cluster client

* merge master

* cache returns unknown instead of T

* update cache service, tests and doc

* remove console.log

* do not cache null or undefined values

* fix merge

* lint fix

packages/cli/src/services/redis/RedisServiceBaseClasses.ts

@@ -0,0 +1,74 @@
+import type Redis from 'ioredis';
+import type { Cluster } from 'ioredis';
+import { getDefaultRedisClient } from './RedisServiceHelper';
+import { LoggerProxy } from 'n8n-workflow';
+
+export type RedisClientType =
+	| 'subscriber'
+	| 'client'
+	| 'bclient'
+	| 'subscriber(bull)'
+	| 'client(bull)'
+	| 'bclient(bull)'
+	| 'client(cache)'
+	| 'publisher'
+	| 'consumer'
+	| 'producer'
+	| 'list-sender'
+	| 'list-receiver';
+
+export type RedisServiceMessageHandler =
+	| ((channel: string, message: string) => void)
+	| ((stream: string, id: string, message: string[]) => void);
+
+class RedisServiceBase {
+	redisClient: Redis | Cluster | undefined;
+
+	isInitialized = false;
+
+	async init(type: RedisClientType = 'client'): Promise<void> {
+		if (this.redisClient && this.isInitialized) {
+			return;
+		}
+		this.redisClient = await getDefaultRedisClient(undefined, type);
+
+		this.redisClient.on('close', () => {
+			LoggerProxy.warn('Redis unavailable - trying to reconnect...');
+		});
+
+		this.redisClient.on('error', (error) => {
+			if (!String(error).includes('ECONNREFUSED')) {
+				// eslint-disable-next-line @typescript-eslint/no-unsafe-argument
+				LoggerProxy.warn('Error with Redis: ', error);
+			}
+		});
+	}
+
+	async destroy(): Promise<void> {
+		if (!this.redisClient) {
+			return;
+		}
+		await this.redisClient.quit();
+		this.redisClient = undefined;
+	}
+}
+
+export abstract class RedisServiceBaseSender extends RedisServiceBase {
+	senderId: string;
+
+	setSenderId(senderId?: string): void {
+		this.senderId = senderId ?? '';
+	}
+}
+
+export abstract class RedisServiceBaseReceiver extends RedisServiceBase {
+	messageHandlers: Map<string, RedisServiceMessageHandler> = new Map();
+
+	addMessageHandler(handlerName: string, handler: RedisServiceMessageHandler): void {
+		this.messageHandlers.set(handlerName, handler);
+	}
+
+	removeMessageHandler(handlerName: string): void {
+		this.messageHandlers.delete(handlerName);
+	}
+}