feat(i18n): #352 다국어 뼈대 ko/en/ja/es

- next-intl 5.x 도입 - src/i18n/config.ts: LOCALES 상수, detectBrowserLocale, LOCALE_LABELS(국기/네이티브명) - src/i18n/LocaleProvider.tsx: NextIntlClientProvider wrap + localStorage tasteby_locale 저장 - src/messages/{ko,en,ja,es}.json: 초기 30개 키 (header/actions/filter/restaurant/review 5 카테고리) - src/components/LanguageSwitcher.tsx: 헤더용 드롭다운 (국기 + native, ARIA listbox, 44px 터치) - providers.tsx: LocaleProvider로 AuthProvider 감싸기 - page.tsx 헤더에 LanguageSwitcher 배치 설계서: docs/design/352-i18n-skeleton/README.md (Approved) 언어 선택 근거: - ko: 기본 - en: 글로벌 1순위 - ja: 일본 사용자 + 한국 음식 관광 - es: 5억 화자, 라틴아메리카 + 스페인 확장 미번역 키는 ko fallback. URL 라우팅(/en/)/SEO meta/사용자 콘텐츠 번역은 후속. Refs: #352
2026-06-15 15:58:21 +09:00
parent fda2d76514
commit 6cbf7feaf5
12 changed files with 1164 additions and 4 deletions
--- a/docs/design/352-i18n-skeleton/README.md
+++ b/docs/design/352-i18n-skeleton/README.md
@@ -0,0 +1,141 @@
+# 설계서: i18n 뼈대 — ko/en/ja/es (#352)
+
+> **상태**: Approved
+> **작성**: [AI] Architect · **최종수정**: 2026-06-15
+> **추적성** — Redmine: #352
+> · 구현 파일: `frontend/package.json`, `frontend/next.config.ts`, `frontend/src/i18n/*` (신규), `frontend/src/messages/{ko,en,ja,es}.json` (신규), `frontend/src/components/LanguageSwitcher.tsx` (신규)
+> · 테스트: 수동 (언어 전환 + ko fallback)
+
+## 1. 목적
+
+장기적으로 영어/일본어/스페인어 시장으로 확장 가능하도록 i18n 뼈대 구축. 본 이슈는 *뼈대*만 — 약 30개 키 초기 번역.
+
+## 2. 범위
+
+- **포함**
+  - `next-intl` 라이브러리 도입 (Next.js 16 App Router 권장).
+  - 4개 로케일: `ko, en, ja, es`. 기본 `ko`, fallback `ko`.
+  - 메시지 디렉토리 `src/messages/{ko,en,ja,es}.json`.
+  - Provider (`<NextIntlClientProvider>`) 루트 layout 적용.
+  - `LanguageSwitcher` 컴포넌트 (헤더 우측).
+  - 로케일 저장: localStorage `tasteby_locale`.
+  - 초기 번역 키 ~30개: 헤더(로그인/검색/메뉴) + 주요 액션(저장/취소/삭제/확인) + 페이지 제목.
+- **제외**
+  - URL 라우팅 i18n (`/ko/...`).
+  - SEO meta tags i18n.
+  - 식당명/리뷰 등 사용자 콘텐츠 번역.
+  - 어드민 페이지(운영자만 사용, 한국어 유지).
+  - 식당 카드/상세 시트 전체 키 추출 (점진).
+
+## 3. 인수조건
+
+- [ ] `npm i next-intl` + 4개 메시지 파일 생성.
+- [ ] `tasteby_locale`이 localStorage에 있으면 사용, 없으면 브라우저 언어 감지(`navigator.language`) → 매칭 안되면 `ko`.
+- [ ] 헤더 우측 LanguageSwitcher 드롭다운(국기 + 코드).
+- [ ] 초기 번역 키 약 30개 — 4개 언어 모두 채움.
+- [ ] 미번역 키는 `ko` fallback (에러 없이).
+- [ ] 빌드/배포 회귀 없음.
+
+## 4. 컨텍스트 & 제약
+
+- Next.js 16 + App Router + `"use client"` 컴포넌트 다수.
+- 기존 `auth-context`처럼 i18n도 React Context 패턴.
+- `next-intl`은 server/client 모두 지원, 본 프로젝트는 client-side switching이라 `NextIntlClientProvider` 중심.
+- URL 라우팅 변경 없이 단순 메시지만 교체(낮은 비용).
+- 폰트: Pretendard Variable이 한국어/영어 잘 표시, 일본어는 시스템 폰트 fallback OK, 스페인어는 라틴 문자라 OK.
+
+## 5. 아키텍처 개요
+
+```
+frontend/
+├── src/
+│   ├── i18n/
+│   │   ├── config.ts            ← 로케일 목록/기본값 상수
+│   │   ├── LocaleProvider.tsx   ← NextIntlClientProvider wrap + localStorage 저장
+│   │   └── useTranslations.ts   ← (next-intl 재export)
+│   ├── messages/
+│   │   ├── ko.json              ← 기본
+│   │   ├── en.json
+│   │   ├── ja.json
+│   │   └── es.json
+│   ├── components/
+│   │   └── LanguageSwitcher.tsx ← 헤더용
+│   └── app/
+│       └── layout.tsx           ← LocaleProvider로 감싸기
+```
+
+## 6. 데이터 모델
+
+### 메시지 키 (초기 ~30)
+```json
+{
+  "header": {
+    "search": "검색", "login": "로그인", "logout": "로그아웃",
+    "menu": "메뉴", "myReviews": "내 리뷰", "favorites": "즐겨찾기"
+  },
+  "actions": {
+    "save": "저장", "cancel": "취소", "delete": "삭제",
+    "edit": "수정", "confirm": "확인", "close": "닫기",
+    "loading": "로딩 중...", "submit": "제출"
+  },
+  "filter": {
+    "title": "필터", "cuisine": "음식 종류", "price": "가격대",
+    "region": "지역", "channel": "채널", "reset": "초기화"
+  },
+  "restaurant": {
+    "rating": "평점", "address": "주소", "phone": "전화",
+    "website": "웹사이트", "closed": "폐업", "tempClosed": "임시휴업"
+  },
+  "review": {
+    "title": "리뷰", "write": "리뷰 작성", "noReviews": "아직 리뷰가 없습니다"
+  }
+}
+```
+
+총 5개 카테고리 × 평균 6개 = 30개 키.
+
+## 7. 함수 명세
+
+| 함수/컴포넌트 | 책임 | 비고 |
+|---|---|---|
+| `i18n/config.ts` | LOCALES, DEFAULT_LOCALE 상수 | 단순 |
+| `LocaleProvider.tsx` | NextIntlClientProvider wrap + 메시지 동적 로딩 + localStorage 동기화 | client |
+| `LanguageSwitcher.tsx` | 헤더 드롭다운 (국기 + 코드) | client, 44px 터치 |
+| `messages/<lang>.json` | 키 → 텍스트 | flat or nested |
+
+## 8. 흐름
+
+1. 사용자 첫 방문 → `tasteby_locale` 없음 → `navigator.language.split('-')[0]`이 LOCALES에 있으면 사용, 아니면 `ko`.
+2. LocaleProvider가 해당 로케일 메시지 파일 import → NextIntlClientProvider에 전달.
+3. 컴포넌트는 `useTranslations('header')` 등으로 호출.
+4. LanguageSwitcher에서 변경 → localStorage 저장 → 페이지 새로고침 또는 state 업데이트.
+
+## 9. 엣지케이스
+
+- **메시지 파일 누락 키**: next-intl 기본 동작은 키 자체 표시 + 콘솔 경고. fallback 처리는 messages 명시.
+- **localStorage 비활성/SSR**: typeof window 체크.
+- **로케일 코드 대소문자**: 항상 소문자 정규화.
+- **placeholder 변수**: next-intl ICU 메시지 형식 지원 (`{name}` 등). 초기 키에는 미적용.
+
+## 10. 테스트
+
+- 수동:
+  - 한국어 첫 방문 → "검색" 표시.
+  - LanguageSwitcher에서 English → "Search" 표시.
+  - 새로고침 후 영어 유지.
+  - 메시지 누락 키 → 콘솔 경고 + 키 표시.
+
+## 11. 리스크 & 대안
+
+- **선택**: `next-intl` (Next.js 16 App Router 권장, ICU 메시지, 활발 유지보수).
+- **대안 A**: `react-i18next` — 더 일반적이지만 App Router 통합 next-intl이 더 매끄러움.
+- **대안 B**: 자체 구현 + Context — 의존성 ↓ but 기능/표준화 ↓.
+- **트레이드오프**: 30개 키는 단순하지만 ICU 메시지(복수형, 성별 등) 필요 시 next-intl 가치 큼.
+
+## 12. 미해결 질문
+
+- 식당명/리뷰 콘텐츠 번역 — 사용자 작성이라 자동 번역(LLM)? 별도 정책 결정.
+- URL 라우팅 i18n (`/en/`) — 후속.
+- SEO meta tags i18n — 후속.
+- 어드민 페이지는 운영자 한국어 유지 — 확정.
+- 통화/날짜 포맷(Intl API) — 후속.
--- a/frontend/package-lock.json
+++ b/frontend/package-lock.json
@@ -8,11 +8,13 @@
      "name": "frontend",
      "version": "0.1.0",
      "dependencies": {
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        "@react-oauth/google": "^0.13.4",
        "@tabler/icons-react": "^3.40.0",
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        "@vis.gl/react-google-maps": "^1.7.1",
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+    "node_modules/next-intl-swc-plugin-extractor": {
+      "version": "4.13.0",
+      "resolved": "https://registry.npmjs.org/next-intl-swc-plugin-extractor/-/next-intl-swc-plugin-extractor-4.13.0.tgz",
+      "integrity": "sha512-6S/fJI0KXvLCL8nhBo9P8eGaJPzmwJBTCzX0NaUIj0VyU8U89d//T+vjMLdNIXl5MlLaYH7B9MbAjb8Mvu+tqQ==",
+      "license": "MIT"
+    },
+    "node_modules/next-intl/node_modules/@swc/core": {
+      "version": "1.15.41",
+      "resolved": "https://registry.npmjs.org/@swc/core/-/core-1.15.41.tgz",
+      "integrity": "sha512-03nQq/082QRJJiOvp3FGbgxTGyyxMxohPTjhk/W9bD2J0tk4ukITI7goOhOO2WbaHn/lsPmo/zf8+DIXhwpgYQ==",
+      "hasInstallScript": true,
+      "license": "Apache-2.0",
+      "dependencies": {
+        "@swc/counter": "^0.1.3",
+        "@swc/types": "^0.1.26"
+      },
+      "engines": {
+        "node": ">=10"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/swc"
+      },
+      "optionalDependencies": {
+        "@swc/core-darwin-arm64": "1.15.41",
+        "@swc/core-darwin-x64": "1.15.41",
+        "@swc/core-linux-arm-gnueabihf": "1.15.41",
+        "@swc/core-linux-arm64-gnu": "1.15.41",
+        "@swc/core-linux-arm64-musl": "1.15.41",
+        "@swc/core-linux-ppc64-gnu": "1.15.41",
+        "@swc/core-linux-s390x-gnu": "1.15.41",
+        "@swc/core-linux-x64-gnu": "1.15.41",
+        "@swc/core-linux-x64-musl": "1.15.41",
+        "@swc/core-win32-arm64-msvc": "1.15.41",
+        "@swc/core-win32-ia32-msvc": "1.15.41",
+        "@swc/core-win32-x64-msvc": "1.15.41"
+      },
+      "peerDependencies": {
+        "@swc/helpers": ">=0.5.17"
+      },
+      "peerDependenciesMeta": {
+        "@swc/helpers": {
+          "optional": true
+        }
+      }
+    },
    "node_modules/next/node_modules/postcss": {
      "version": "8.4.31",
      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.4.31.tgz",
@@ -5152,6 +5825,12 @@
        "node": "^10 || ^12 || >=14"
      }
    },
+    "node_modules/node-addon-api": {
+      "version": "7.1.1",
+      "resolved": "https://registry.npmjs.org/node-addon-api/-/node-addon-api-7.1.1.tgz",
+      "integrity": "sha512-5m3bsyrjFWE1xf7nz7YXdN4udnVtXK6/Yfgn5qnahL6bCkf2yKt4k3nuTKAtT4r3IG8JNR2ncsIMdZuAzJjHQQ==",
+      "license": "MIT"
+    },
    "node_modules/node-exports-info": {
      "version": "1.6.0",
      "resolved": "https://registry.npmjs.org/node-exports-info/-/node-exports-info-1.6.0.tgz",
@@ -5428,6 +6107,12 @@
        "url": "https://github.com/sponsors/jonschlinkert"
      }
    },
+    "node_modules/po-parser": {
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/po-parser/-/po-parser-2.1.1.tgz",
+      "integrity": "sha512-ECF4zHLbUItpUgE3OTtLKlPjeBN+fKEczj2zYjDfCGOzicNs0GK3Vg2IoAYwx7LH/XYw43fZQP6xnZ4TkNxSLQ==",
+      "license": "MIT"
+    },
    "node_modules/possible-typed-array-names": {
      "version": "1.1.0",
      "resolved": "https://registry.npmjs.org/possible-typed-array-names/-/possible-typed-array-names-1.1.0.tgz",
@@ -6531,6 +7216,27 @@
        "punycode": "^2.1.0"
      }
    },
+    "node_modules/use-intl": {
+      "version": "4.13.0",
+      "resolved": "https://registry.npmjs.org/use-intl/-/use-intl-4.13.0.tgz",
+      "integrity": "sha512-fAFDrWaASxlhXOipcOyb5VDD+YONqj6+8O8EcG/J7RBoOUF3A8YahRWLN+mBxYMrlMQB8N6Voqk5X+YC+HSL0A==",
+      "funding": [
+        {
+          "type": "individual",
+          "url": "https://github.com/sponsors/amannn"
+        }
+      ],
+      "license": "MIT",
+      "dependencies": {
+        "@formatjs/fast-memoize": "^3.1.0",
+        "@schummar/icu-type-parser": "1.21.5",
+        "icu-minify": "^4.13.0",
+        "intl-messageformat": "^11.1.0"
+      },
+      "peerDependencies": {
+        "react": "^17.0.0 || ^18.0.0 || >=19.0.0-rc <19.0.0 || ^19.0.0"
+      }
+    },
    "node_modules/which": {
      "version": "2.0.2",
      "resolved": "https://registry.npmjs.org/which/-/which-2.0.2.tgz",
--- a/frontend/package.json
+++ b/frontend/package.json
@@ -9,11 +9,13 @@
    "lint": "eslint"
  },
  "dependencies": {
+    "@phosphor-icons/react": "^2.1.10",
    "@react-oauth/google": "^0.13.4",
    "@tabler/icons-react": "^3.40.0",
    "@types/supercluster": "^7.1.3",
    "@vis.gl/react-google-maps": "^1.7.1",
    "next": "16.1.6",
+    "next-intl": "^4.13.0",
    "react": "19.2.3",
    "react-dom": "19.2.3",
    "supercluster": "^8.0.1"
--- a/frontend/src/app/page.tsx
+++ b/frontend/src/app/page.tsx
@@ -3,6 +3,7 @@
 import { useCallback, useEffect, useMemo, useRef, useState } from "react";
 import { GoogleLogin } from "@react-oauth/google";
 import LoginMenu from "@/components/LoginMenu";
+import LanguageSwitcher from "@/components/LanguageSwitcher";
 import { api } from "@/lib/api";
 import type { Restaurant, Channel, Review, Memo } from "@/lib/api";
 import { useAuth } from "@/lib/auth-context";
@@ -719,6 +720,8 @@ export default function Home() {
                </>
              )}
              <div className="flex-1" />
+              {/* #352 — Language switcher */}
+              <LanguageSwitcher />
              {/* Desktop user area */}
              {authLoading ? null : user ? (
                <div className="flex items-center gap-2 shrink-0">
--- a/frontend/src/app/providers.tsx
+++ b/frontend/src/app/providers.tsx
@@ -2,6 +2,7 @@

 import { GoogleOAuthProvider } from "@react-oauth/google";
 import { AuthProvider } from "@/lib/auth-context";
+import { LocaleProvider } from "@/i18n/LocaleProvider";
 import type { ReactNode } from "react";

 const GOOGLE_CLIENT_ID = process.env.NEXT_PUBLIC_GOOGLE_CLIENT_ID || "";
@@ -9,7 +10,9 @@ const GOOGLE_CLIENT_ID = process.env.NEXT_PUBLIC_GOOGLE_CLIENT_ID || "";
 export function Providers({ children }: { children: ReactNode }) {
  return (
    <GoogleOAuthProvider clientId={GOOGLE_CLIENT_ID}>
-      <AuthProvider>{children}</AuthProvider>
+      <LocaleProvider>
+        <AuthProvider>{children}</AuthProvider>
+      </LocaleProvider>
    </GoogleOAuthProvider>
  );
 }
--- a/frontend/src/components/LanguageSwitcher.tsx
+++ b/frontend/src/components/LanguageSwitcher.tsx
@@ -0,0 +1,57 @@
+"use client";
+
+import { useState } from "react";
+import { useLocale } from "@/i18n/LocaleProvider";
+import { LOCALES, LOCALE_LABELS } from "@/i18n/config";
+
+// #352 — 헤더용 언어 전환 드롭다운. 44px 터치 영역 + ARIA listbox 패턴.
+export default function LanguageSwitcher() {
+  const { locale, setLocale } = useLocale();
+  const [open, setOpen] = useState(false);
+
+  return (
+    <div className="relative">
+      <button
+        onClick={() => setOpen((v) => !v)}
+        aria-haspopup="listbox"
+        aria-expanded={open}
+        aria-label="언어 선택 / Select language"
+        className="min-h-[44px] min-w-[44px] px-2 py-1.5 flex items-center gap-1 text-sm rounded-lg hover:bg-brand-50 touch-manipulation"
+      >
+        <span aria-hidden="true">{LOCALE_LABELS[locale].flag}</span>
+        <span className="text-xs text-gray-500 uppercase">{locale}</span>
+      </button>
+      {open && (
+        <>
+          <button
+            aria-hidden="true"
+            tabIndex={-1}
+            className="fixed inset-0 z-40 cursor-default"
+            onClick={() => setOpen(false)}
+          />
+          <ul
+            role="listbox"
+            aria-label="언어 목록"
+            className="absolute right-0 mt-1 bg-surface rounded-lg shadow-lg border border-gray-200 dark:border-gray-700 py-1 z-50 min-w-[160px]"
+          >
+            {LOCALES.map((l) => (
+              <li key={l}>
+                <button
+                  role="option"
+                  aria-selected={l === locale}
+                  onClick={() => { setLocale(l); setOpen(false); }}
+                  className={`w-full text-left px-3 py-2 text-sm flex items-center gap-2 hover:bg-brand-50 ${
+                    l === locale ? "font-semibold text-brand-700" : "text-gray-700"
+                  }`}
+                >
+                  <span aria-hidden="true">{LOCALE_LABELS[l].flag}</span>
+                  <span>{LOCALE_LABELS[l].native}</span>
+                </button>
+              </li>
+            ))}
+          </ul>
+        </>
+      )}
+    </div>
+  );
+}
--- a/frontend/src/i18n/LocaleProvider.tsx
+++ b/frontend/src/i18n/LocaleProvider.tsx
@@ -0,0 +1,56 @@
+"use client";
+
+import { NextIntlClientProvider } from "next-intl";
+import { useEffect, useState } from "react";
+import { DEFAULT_LOCALE, LOCALE_STORAGE_KEY, Locale, detectBrowserLocale, isLocale } from "./config";
+
+// #352 — 메시지 파일을 정적 import (Tree-shaking 가능, 클라이언트 번들에 4언어 모두 포함되지만
+// 30개 키 수준이라 부담 미미. 키가 늘어나면 동적 import로 분할 검토)
+import ko from "@/messages/ko.json";
+import en from "@/messages/en.json";
+import ja from "@/messages/ja.json";
+import es from "@/messages/es.json";
+
+const MESSAGES: Record<Locale, typeof ko> = { ko, en, ja, es };
+
+interface LocaleContextValue {
+  locale: Locale;
+  setLocale: (l: Locale) => void;
+}
+
+import { createContext, useContext } from "react";
+const LocaleContext = createContext<LocaleContextValue | null>(null);
+
+export function useLocale() {
+  const ctx = useContext(LocaleContext);
+  if (!ctx) throw new Error("useLocale must be used within LocaleProvider");
+  return ctx;
+}
+
+export function LocaleProvider({ children }: { children: React.ReactNode }) {
+  // SSR 단계는 기본 로케일로 시작 (hydration mismatch 방지)
+  const [locale, setLocaleState] = useState<Locale>(DEFAULT_LOCALE);
+
+  useEffect(() => {
+    if (typeof window === "undefined") return;
+    const saved = localStorage.getItem(LOCALE_STORAGE_KEY);
+    const initial: Locale = isLocale(saved) ? saved : detectBrowserLocale();
+    if (initial !== locale) setLocaleState(initial);
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, []);
+
+  const setLocale = (l: Locale) => {
+    setLocaleState(l);
+    if (typeof window !== "undefined") {
+      localStorage.setItem(LOCALE_STORAGE_KEY, l);
+    }
+  };
+
+  return (
+    <LocaleContext.Provider value={{ locale, setLocale }}>
+      <NextIntlClientProvider locale={locale} messages={MESSAGES[locale]}>
+        {children}
+      </NextIntlClientProvider>
+    </LocaleContext.Provider>
+  );
+}
--- a/frontend/src/i18n/config.ts
+++ b/frontend/src/i18n/config.ts
@@ -0,0 +1,28 @@
+// #352 i18n 뼈대 — 로케일 목록/기본값
+
+export const LOCALES = ["ko", "en", "ja", "es"] as const;
+export type Locale = (typeof LOCALES)[number];
+
+export const DEFAULT_LOCALE: Locale = "ko";
+export const LOCALE_STORAGE_KEY = "tasteby_locale";
+
+export const LOCALE_LABELS: Record<Locale, { flag: string; label: string; native: string }> = {
+  ko: { flag: "🇰🇷", label: "Korean", native: "한국어" },
+  en: { flag: "🇺🇸", label: "English", native: "English" },
+  ja: { flag: "🇯🇵", label: "Japanese", native: "日本語" },
+  es: { flag: "🇪🇸", label: "Spanish", native: "Español" },
+};
+
+export function isLocale(value: string | null | undefined): value is Locale {
+  return value != null && (LOCALES as readonly string[]).includes(value);
+}
+
+/**
+ * 브라우저 언어 감지 → 지원 로케일이면 그것, 아니면 기본값.
+ * SSR-safe (typeof window 체크 호출자).
+ */
+export function detectBrowserLocale(): Locale {
+  if (typeof navigator === "undefined") return DEFAULT_LOCALE;
+  const code = navigator.language.split("-")[0].toLowerCase();
+  return isLocale(code) ? code : DEFAULT_LOCALE;
+}
--- a/frontend/src/messages/en.json
+++ b/frontend/src/messages/en.json
@@ -0,0 +1,41 @@
+{
+  "header": {
+    "search": "Search",
+    "login": "Sign In",
+    "logout": "Sign Out",
+    "menu": "Menu",
+    "myReviews": "My Reviews",
+    "favorites": "Favorites"
+  },
+  "actions": {
+    "save": "Save",
+    "cancel": "Cancel",
+    "delete": "Delete",
+    "edit": "Edit",
+    "confirm": "OK",
+    "close": "Close",
+    "loading": "Loading...",
+    "submit": "Submit"
+  },
+  "filter": {
+    "title": "Filter",
+    "cuisine": "Cuisine",
+    "price": "Price Range",
+    "region": "Region",
+    "channel": "Channel",
+    "reset": "Reset"
+  },
+  "restaurant": {
+    "rating": "Rating",
+    "address": "Address",
+    "phone": "Phone",
+    "website": "Website",
+    "closed": "Permanently Closed",
+    "tempClosed": "Temporarily Closed"
+  },
+  "review": {
+    "title": "Reviews",
+    "write": "Write a Review",
+    "noReviews": "No reviews yet"
+  }
+}
--- a/frontend/src/messages/es.json
+++ b/frontend/src/messages/es.json
@@ -0,0 +1,41 @@
+{
+  "header": {
+    "search": "Buscar",
+    "login": "Iniciar sesión",
+    "logout": "Cerrar sesión",
+    "menu": "Menú",
+    "myReviews": "Mis reseñas",
+    "favorites": "Favoritos"
+  },
+  "actions": {
+    "save": "Guardar",
+    "cancel": "Cancelar",
+    "delete": "Eliminar",
+    "edit": "Editar",
+    "confirm": "Aceptar",
+    "close": "Cerrar",
+    "loading": "Cargando...",
+    "submit": "Enviar"
+  },
+  "filter": {
+    "title": "Filtro",
+    "cuisine": "Tipo de cocina",
+    "price": "Rango de precios",
+    "region": "Región",
+    "channel": "Canal",
+    "reset": "Restablecer"
+  },
+  "restaurant": {
+    "rating": "Calificación",
+    "address": "Dirección",
+    "phone": "Teléfono",
+    "website": "Sitio web",
+    "closed": "Cerrado permanentemente",
+    "tempClosed": "Cerrado temporalmente"
+  },
+  "review": {
+    "title": "Reseñas",
+    "write": "Escribir una reseña",
+    "noReviews": "Aún no hay reseñas"
+  }
+}
--- a/frontend/src/messages/ja.json
+++ b/frontend/src/messages/ja.json
@@ -0,0 +1,41 @@
+{
+  "header": {
+    "search": "検索",
+    "login": "ログイン",
+    "logout": "ログアウト",
+    "menu": "メニュー",
+    "myReviews": "マイレビュー",
+    "favorites": "お気に入り"
+  },
+  "actions": {
+    "save": "保存",
+    "cancel": "キャンセル",
+    "delete": "削除",
+    "edit": "編集",
+    "confirm": "確認",
+    "close": "閉じる",
+    "loading": "読み込み中...",
+    "submit": "送信"
+  },
+  "filter": {
+    "title": "フィルター",
+    "cuisine": "料理ジャンル",
+    "price": "価格帯",
+    "region": "地域",
+    "channel": "チャンネル",
+    "reset": "リセット"
+  },
+  "restaurant": {
+    "rating": "評価",
+    "address": "住所",
+    "phone": "電話",
+    "website": "ウェブサイト",
+    "closed": "閉店",
+    "tempClosed": "一時休業"
+  },
+  "review": {
+    "title": "レビュー",
+    "write": "レビューを書く",
+    "noReviews": "まだレビューがありません"
+  }
+}
--- a/frontend/src/messages/ko.json
+++ b/frontend/src/messages/ko.json
@@ -0,0 +1,41 @@
+{
+  "header": {
+    "search": "검색",
+    "login": "로그인",
+    "logout": "로그아웃",
+    "menu": "메뉴",
+    "myReviews": "내 리뷰",
+    "favorites": "즐겨찾기"
+  },
+  "actions": {
+    "save": "저장",
+    "cancel": "취소",
+    "delete": "삭제",
+    "edit": "수정",
+    "confirm": "확인",
+    "close": "닫기",
+    "loading": "로딩 중...",
+    "submit": "제출"
+  },
+  "filter": {
+    "title": "필터",
+    "cuisine": "음식 종류",
+    "price": "가격대",
+    "region": "지역",
+    "channel": "채널",
+    "reset": "초기화"
+  },
+  "restaurant": {
+    "rating": "평점",
+    "address": "주소",
+    "phone": "전화",
+    "website": "웹사이트",
+    "closed": "폐업",
+    "tempClosed": "임시휴업"
+  },
+  "review": {
+    "title": "리뷰",
+    "write": "리뷰 작성",
+    "noReviews": "아직 리뷰가 없습니다"
+  }
+}