pass redis config as-is to postgres cache

also, explicitly state that `path` is a valid config option for
redis (tells `ioredis` to connect via UNIX socked instead of TCP
socket)

packages/backend/src/config.ts

@@ -12,9 +12,10 @@ import * as Sentry from '@sentry/node';
 import type { RedisOptions } from 'ioredis';
 
 type RedisOptionsSource = Partial<RedisOptions> & {
-	host: string;
-	port: number;
+	host?: string;
+	port?: number;
 	family?: number;
+	path?: string,
 	pass: string;
 	db?: number;
 	prefix?: string;

packages/backend/src/postgres.ts

@@ -236,12 +236,8 @@ export function createPostgresDataSource(config: Config) {
 		cache: !config.db.disableCache && process.env.NODE_ENV !== 'test' ? { // dbをcloseしても何故かredisのコネクションが内部的に残り続けるようで、テストの際に支障が出るため無効にする(キャッシュも含めてテストしたいため本当は有効にしたいが...)
 			type: 'ioredis',
 			options: {
-				host: config.redis.host,
-				port: config.redis.port,
-				family: config.redis.family ?? 0,
-				password: config.redis.pass,
+				...config.redis,
 				keyPrefix: `${config.redis.prefix}:query:`,
-				db: config.redis.db ?? 0,
 			},
 		} : false,
 		logging: log,