add a redis service to handle redis connection

server/service/redisService.js

@@ -0,0 +1,71 @@
+class RedisService {
+	static SERVICE_NAME = "RedisService";
+
+	constructor({ logger, IORedis, SettingsService }) {
+		this.logger = logger;
+		this.IORedis = IORedis;
+		this.SettingsService = SettingsService;
+		this.connection = null;
+	}
+
+	static async createInstance({ logger, IORedis, SettingsService }) {
+		const instance = new RedisService({ logger, IORedis, SettingsService });
+		await instance.connect();
+		return instance;
+	}
+
+	async connect() {
+		const settings = this.SettingsService.getSettings();
+		const { redisUrl } = settings;
+		this.connection = new this.IORedis(redisUrl, {
+			maxRetriesPerRequest: null,
+			retryStrategy: (times) => {
+				if (times >= 5) {
+					throw new Error("Failed to connect to Redis");
+				}
+				this.logger.debug({
+					message: "Retrying Redis connection",
+					service: RedisService.SERVICE_NAME,
+					details: { times },
+				});
+				return Math.min(times * 100, 2000);
+			},
+		});
+		await new Promise((resolve, reject) => {
+			let errorOccurred = false;
+
+			this.connection.on("ready", () => {
+				if (!errorOccurred) {
+					this.logger.info({
+						message: "Redis connection established",
+						service: RedisService.SERVICE_NAME,
+					});
+					resolve();
+				}
+			});
+
+			this.connection.on("error", (err) => {
+				errorOccurred = true;
+				this.logger.error({
+					message: "Redis connection error",
+					service: RedisService.SERVICE_NAME,
+					error: err,
+				});
+				setTimeout(() => reject(err), 5000);
+			});
+		});
+	}
+	async flushall() {
+		this.logger.debug({
+			message: "Flushing all Redis data",
+			service: RedisService.SERVICE_NAME,
+		});
+		await this.connection.flushall();
+	}
+
+	getConnection() {
+		return this.connection;
+	}
+}
+
+export default RedisService;