perf(server): Redis接続をストリーミング接続ごとに作らず、プロセス全体で共有するように

src/db/redis.ts

@@ -1,7 +1,7 @@
 import * as redis from 'redis';
 import config from '../config';
 
-export default redis.createClient(
+const client = redis.createClient(
 	config.redis.port,
 	config.redis.host,
 	{
@@ -10,3 +10,7 @@ export default redis.createClient(
 		db: config.redis.db || 0
 	}
 );
+
+client.subscribe(config.host);
+
+export default client;

src/server/api/streaming.ts

@@ -1,12 +1,11 @@
 import * as http from 'http';
 import * as websocket from 'websocket';
-import * as redis from 'redis';
 
 import MainStreamConnection from './stream';
 import { ParsedUrlQuery } from 'querystring';
 import authenticate from './authenticate';
 import { EventEmitter } from 'events';
-import config from '../../config';
+import redisClient from '../../db/redis';
 
 module.exports = (server: http.Server) => {
 	// Init websocket server
@@ -24,37 +23,21 @@ module.exports = (server: http.Server) => {
 
 		const connection = request.accept();
 
-		let ev: EventEmitter;
+		const ev = new EventEmitter();
 
-		// Connect to Redis
-		const subscriber = redis.createClient(
-			config.redis.port,
-			config.redis.host,
-			{
-				password: config.redis.pass
-			}
-		);
-
-		subscriber.subscribe(config.host);
-
-		ev = new EventEmitter();
-
-		subscriber.on('message', async (_, data) => {
-			const obj = JSON.parse(data);
+		async function onRedisMessage(_: string, data: string) {
+			const parsed = JSON.parse(data);
+			ev.emit(parsed.channel, parsed.message);
+		}
 
-			ev.emit(obj.channel, obj.message);
-		});
-
-		connection.once('close', () => {
-			subscriber.unsubscribe();
-			subscriber.quit();
-		});
+		redisClient.on('message', onRedisMessage);
 
 		const main = new MainStreamConnection(connection, ev, user, app);
 
 		connection.once('close', () => {
 			ev.removeAllListeners();
 			main.dispose();
+			redisClient.off('message', onRedisMessage);
 		});
 
 		connection.on('message', async (data) => {