From d01ea4dfbdb67c834e904f27e7b1227c513cdec8 Mon Sep 17 00:00:00 2001
From: chanwoo7 <chanwoo9987@gmail.com>
Date: Wed, 2 Sep 2026 04:30:48 +0900
Subject: [PATCH 1/5] =?UTF-8?q?feat(conversation):=20=EC=8B=A4=EC=8B=9C?=
 =?UTF-8?q?=EA=B0=84=20subscription=20=E2=80=94=20graphql-ws=20+=20Redis?=
 =?UTF-8?q?=20PubSub?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

figma 알림센터 화면 대응 4/4. 채팅 신규 메시지와 대화 목록/배지 갱신을
실시간 구독으로 제공한다(구매자·판매자 양측, 사용자 확정 정책).

변경점
- 인프라: graphql-ws 전송 + Redis PubSub(graphql-redis-subscriptions,
  ioredis). 전역 PubSubModule(PUB_SUB 토큰 — cross-cutting 포트라 토큰
  주입, spec은 in-memory PubSub 대체). REDIS_URL 미설정 시
  redis://localhost:6379 폴백(개발 단계 로컬 DX 우선, README·compose 갱신)
- ws 인증: connectionParams.authorization을 upgrade 요청 헤더로 이식하는
  buildGraphqlContext로 기존 JwtAuthGuard/passport 경로 재사용(가드 이원화
  방지)
- Subscription 3종: conversationMessageAdded(대화 소유 구매자/해당 매장
  판매자만, 존재 여부 비노출), myConversationUpdated(구매자 목록·배지),
  sellerConversationUpdated(판매자 목록)
- 발행 지점: 구매자 텍스트/FAQ 전송·판매자 답장 서비스에서 저장 후 발행
  (트랜잭션 밖 부수효과 — 실패해도 전송은 성공, 구독자는 재조회 폴백).
  이벤트 payload는 Redis JSON 왕복을 고려해 날짜를 ISO 문자열로 나른다
- 토픽 조립은 ConversationEventsService 단일 소스(발행자·구독자 공유)

회귀 테스트
- events service 실 Redis(testcontainers) 왕복 2케이스(토픽 격리·payload
  보존), subscription service 실DB 4케이스(권한 3종 + 발행 경로 통합 수신),
  이벤트 매퍼 2케이스, ws 컨텍스트 헬퍼 3케이스
- 로컬 스모크: 인증 ws 구독 → HTTP mutation → Redis 경유 이벤트 수신 확인
---
 README.md                                     |   1 +
 docker-compose.yml                            |  12 ++
 package.json                                  |   4 +
 src/app.module.ts                             |  30 +--
 src/config/redis.config.ts                    |  20 ++
 .../conversation-subscription.graphql         |  32 ++++
 .../conversation/conversation.module.ts       |   8 +-
 src/features/conversation/index.ts            |   3 +
 .../repositories/conversation.repository.ts   |  29 +++
 .../conversation-center.resolver.spec.ts      |   5 +
 .../conversation-inquiry.resolver.spec.ts     |   5 +
 .../conversation-subscription.resolver.ts     |  54 ++++++
 ...conversation-events-mappers.helper.spec.ts |  47 +++++
 .../conversation-events-mappers.helper.ts     |  33 ++++
 .../conversation-events.service.spec.ts       | 116 +++++++++++
 .../services/conversation-events.service.ts   |  70 +++++++
 .../conversation-inquiry.service.spec.ts      |  11 +-
 .../services/conversation-inquiry.service.ts  |  63 +++++-
 .../conversation-subscription.service.spec.ts | 180 ++++++++++++++++++
 .../conversation-subscription.service.ts      |  60 ++++++
 .../types/conversation-output.type.ts         |  30 +++
 src/features/core/root.graphql                |   5 +
 .../seller-conversation.resolver.spec.ts      |   5 +
 .../seller-conversation.service.spec.ts       |   5 +
 .../services/seller-conversation.service.ts   |  74 ++++++-
 .../graphql/graphql-context.helper.spec.ts    |  39 ++++
 src/global/graphql/graphql-context.helper.ts  |  34 ++++
 src/global/pubsub/index.ts                    |   2 +
 src/global/pubsub/pubsub.constants.ts         |   5 +
 src/global/pubsub/pubsub.module.ts            |  43 +++++
 yarn.lock                                     |  88 ++++++++-
 31 files changed, 1094 insertions(+), 19 deletions(-)
 create mode 100644 src/config/redis.config.ts
 create mode 100644 src/features/conversation/conversation-subscription.graphql
 create mode 100644 src/features/conversation/resolvers/conversation-subscription.resolver.ts
 create mode 100644 src/features/conversation/services/conversation-events-mappers.helper.spec.ts
 create mode 100644 src/features/conversation/services/conversation-events-mappers.helper.ts
 create mode 100644 src/features/conversation/services/conversation-events.service.spec.ts
 create mode 100644 src/features/conversation/services/conversation-events.service.ts
 create mode 100644 src/features/conversation/services/conversation-subscription.service.spec.ts
 create mode 100644 src/features/conversation/services/conversation-subscription.service.ts
 create mode 100644 src/global/graphql/graphql-context.helper.spec.ts
 create mode 100644 src/global/graphql/graphql-context.helper.ts
 create mode 100644 src/global/pubsub/index.ts
 create mode 100644 src/global/pubsub/pubsub.constants.ts
 create mode 100644 src/global/pubsub/pubsub.module.ts

diff --git a/README.md b/README.md
index 399441a3..9a6545e0 100644
--- a/README.md
+++ b/README.md
@@ -269,6 +269,7 @@ yarn start:dev
 | --- | --- |
 | **서버** | `NODE_ENV`, `PORT`, `BACKEND_BASE_URL`, `FRONTEND_BASE_URL` |
 | **DB** | `DATABASE_URL` |
+| **Redis (선택)** | `REDIS_URL` — GraphQL subscription PubSub. 미설정 시 `redis://localhost:6379`(로컬 docker-compose) |
 | **JWT / Auth** | `JWT_ACCESS_SECRET`, `JWT_ACCESS_EXPIRES_SECONDS`, `AUTH_REFRESH_EXPIRES_DAYS`, `AUTH_COOKIE_DOMAIN`, `AUTH_COOKIE_SECURE` |
 | **OIDC (Google)** | `OIDC_GOOGLE_CLIENT_ID`, `OIDC_GOOGLE_CLIENT_SECRET`, `OIDC_GOOGLE_ISSUER_URL` |
 | **OIDC (Kakao)** | `OIDC_KAKAO_CLIENT_ID`, `OIDC_KAKAO_CLIENT_SECRET`, `OIDC_KAKAO_ISSUER_URL` |
diff --git a/docker-compose.yml b/docker-compose.yml
index b62f95bf..12910912 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -25,5 +25,17 @@ services:
       timeout: 5s
       retries: 5
 
+  redis:
+    image: redis:7-alpine
+    container_name: caquick-redis
+    # GraphQL subscription PubSub 백엔드. 영속화 불필요(휘발성 이벤트 브로커).
+    ports:
+      - '6379:6379'
+    healthcheck:
+      test: ['CMD', 'redis-cli', 'ping']
+      interval: 10s
+      timeout: 5s
+      retries: 5
+
 volumes:
   caquick-mysql-data:
diff --git a/package.json b/package.json
index 9a07201d..595237ee 100644
--- a/package.json
+++ b/package.json
@@ -58,6 +58,10 @@
     "cookie-parser": "^1.4.7",
     "express": "^5.2.1",
     "graphql": "^16.14.0",
+    "graphql-redis-subscriptions": "^2.7.0",
+    "graphql-subscriptions": "^3.0.0",
+    "graphql-ws": "^6.2.1",
+    "ioredis": "^5.3.2",
     "logform": "^2.7.0",
     "openid-client": "5.7.1",
     "passport": "^0.7.0",
diff --git a/src/app.module.ts b/src/app.module.ts
index b17dcddc..617e0121 100644
--- a/src/app.module.ts
+++ b/src/app.module.ts
@@ -13,13 +13,13 @@ import { ConfigModule, ConfigService } from '@nestjs/config';
 import { GraphQLModule } from '@nestjs/graphql';
 import { ScheduleModule } from '@nestjs/schedule';
 import { ServeStaticModule } from '@nestjs/serve-static';
-import type { Request, Response } from 'express';
 
 import { CommonModule } from '@/common/common.module';
 import authConfig from '@/config/auth.config';
 import databaseConfig from '@/config/database.config';
 import docsConfig from '@/config/docs.config';
 import oidcConfig from '@/config/oidc.config';
+import redisConfig from '@/config/redis.config';
 import s3Config from '@/config/s3.config';
 import { AuthModule } from '@/features/auth/auth.module';
 import { ConversationModule } from '@/features/conversation';
@@ -31,9 +31,11 @@ import { StoreModule } from '@/features/store';
 import { SystemModule } from '@/features/system/system.module';
 import { UserModule } from '@/features/user/user.module';
 import { AuthGlobalModule } from '@/global/auth/auth-global.module';
+import { buildGraphqlContext } from '@/global/graphql/graphql-context.helper';
 import { GraphqlGlobalModule } from '@/global/graphql/graphql.module';
 import { LoggerModule } from '@/global/logger/logger.module';
 import { DocsAccessMiddleware } from '@/global/middlewares/docs-access.middleware';
+import { PubSubModule } from '@/global/pubsub';
 import {
   RequestContextMiddleware,
   RequestContextModule,
@@ -46,7 +48,14 @@ import { PrismaModule } from '@/prisma';
     ConfigModule.forRoot({
       isGlobal: true,
       cache: true,
-      load: [authConfig, databaseConfig, docsConfig, oidcConfig, s3Config],
+      load: [
+        authConfig,
+        databaseConfig,
+        docsConfig,
+        oidcConfig,
+        redisConfig,
+        s3Config,
+      ],
     }),
     ServeStaticModule.forRoot({
       rootPath: join(process.cwd(), 'public'),
@@ -58,6 +67,7 @@ import { PrismaModule } from '@/prisma';
     LoggerModule,
     AuthGlobalModule,
     GraphqlGlobalModule,
+    PubSubModule,
     StorageModule,
     // 인기 검색어 스냅샷 크론(SearchModule) 활성화
     ScheduleModule.forRoot(),
@@ -73,21 +83,17 @@ import { PrismaModule } from '@/prisma';
               : join(process.cwd(), 'src/features/**/*.graphql'),
           ],
           playground: false,
+          // 실시간 subscription(graphql-ws). 인증은 connectionParams →
+          // buildGraphqlContext가 HTTP 헤더로 이식해 기존 JWT 가드를 재사용한다.
+          subscriptions: {
+            'graphql-ws': true,
+          },
           plugins: [
             isProd
               ? ApolloServerPluginLandingPageDisabled()
               : ApolloServerPluginLandingPageLocalDefault({ embed: true }),
           ],
-          context: ({
-            req,
-            res,
-          }: {
-            req: Request;
-            res?: Response;
-          }): {
-            req: Request;
-            res?: Response;
-          } => ({ req, res }),
+          context: buildGraphqlContext,
         };
       },
     }),
diff --git a/src/config/redis.config.ts b/src/config/redis.config.ts
new file mode 100644
index 00000000..47ede9df
--- /dev/null
+++ b/src/config/redis.config.ts
@@ -0,0 +1,20 @@
+import { registerAs } from '@nestjs/config';
+
+/**
+ * Redis 설정 타입 (GraphQL subscription PubSub용)
+ */
+export interface RedisConfig {
+  url: string;
+}
+
+/**
+ * Redis 설정.
+ * DATABASE_URL과 달리 미설정 시 로컬 docker-compose 기본값으로 폴백한다 —
+ * 현재 배포 인프라가 꺼져 있고 FE도 로컬 백엔드로 테스트하는 개발 단계라,
+ * 필수 강제보다 로컬 DX(compose up 후 바로 동작)를 우선한다.
+ */
+export default registerAs('redis', (): RedisConfig => {
+  return {
+    url: process.env.REDIS_URL ?? 'redis://localhost:6379',
+  };
+});
diff --git a/src/features/conversation/conversation-subscription.graphql b/src/features/conversation/conversation-subscription.graphql
new file mode 100644
index 00000000..43806d39
--- /dev/null
+++ b/src/features/conversation/conversation-subscription.graphql
@@ -0,0 +1,32 @@
+extend type Subscription {
+  """
+  대화방 신규 메시지 실시간 구독. 구매자(대화 소유자)와 판매자(해당 매장
+  소유자)만 구독할 수 있다. 인증은 graphql-ws connectionParams.authorization.
+  """
+  conversationMessageAdded(conversationId: ID!): ConversationMessage!
+  """구매자 대화 목록/배지 갱신 이벤트(새 메시지 도착 시)."""
+  myConversationUpdated: ConversationListUpdate!
+  """판매자 대화 목록 갱신 이벤트(고객 메시지 도착 시)."""
+  sellerConversationUpdated: SellerConversationListUpdate!
+}
+
+"""구매자 대화 목록 갱신 이벤트"""
+type ConversationListUpdate {
+  conversationId: ID!
+  storeId: ID!
+  storeName: String!
+  """마지막 메시지 미리보기(HTML은 태그 제거)"""
+  lastMessagePreview: String
+  lastMessageAt: DateTime!
+  """이벤트 시점의 안읽은 수신 메시지 수"""
+  unreadCount: Int!
+}
+
+"""판매자 대화 목록 갱신 이벤트"""
+type SellerConversationListUpdate {
+  conversationId: ID!
+  accountId: ID!
+  """마지막 메시지 미리보기(HTML은 태그 제거)"""
+  lastMessagePreview: String
+  lastMessageAt: DateTime!
+}
diff --git a/src/features/conversation/conversation.module.ts b/src/features/conversation/conversation.module.ts
index a07dcf76..493424e9 100644
--- a/src/features/conversation/conversation.module.ts
+++ b/src/features/conversation/conversation.module.ts
@@ -4,18 +4,24 @@ import { ConversationRepository } from '@/features/conversation/repositories/con
 import { ConversationCenterQueryResolver } from '@/features/conversation/resolvers/conversation-center-query.resolver';
 import { ConversationInquiryMutationResolver } from '@/features/conversation/resolvers/conversation-inquiry-mutation.resolver';
 import { ConversationInquiryQueryResolver } from '@/features/conversation/resolvers/conversation-inquiry-query.resolver';
+import { ConversationSubscriptionResolver } from '@/features/conversation/resolvers/conversation-subscription.resolver';
 import { ConversationCenterService } from '@/features/conversation/services/conversation-center.service';
+import { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
 import { ConversationInquiryService } from '@/features/conversation/services/conversation-inquiry.service';
+import { ConversationSubscriptionService } from '@/features/conversation/services/conversation-subscription.service';
 
 @Module({
   providers: [
     ConversationRepository,
+    ConversationEventsService,
     ConversationInquiryService,
     ConversationCenterService,
+    ConversationSubscriptionService,
     ConversationInquiryQueryResolver,
     ConversationInquiryMutationResolver,
     ConversationCenterQueryResolver,
+    ConversationSubscriptionResolver,
   ],
-  exports: [ConversationRepository],
+  exports: [ConversationRepository, ConversationEventsService],
 })
 export class ConversationModule {}
diff --git a/src/features/conversation/index.ts b/src/features/conversation/index.ts
index 85b8af14..ad05881b 100644
--- a/src/features/conversation/index.ts
+++ b/src/features/conversation/index.ts
@@ -1,3 +1,6 @@
 // cross-feature 공개 API. 단일 구현 repo라 토큰/인터페이스 없이 구체 클래스로 주입(의도적).
 export { ConversationModule } from '@/features/conversation/conversation.module';
 export { ConversationRepository } from '@/features/conversation/repositories/conversation.repository';
+// subscription 이벤트 발행/구독 어댑터 — 판매자 답장(seller feature)도 같은 토픽을 쓴다.
+export { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
+export { toEventPreview } from '@/features/conversation/services/conversation-events-mappers.helper';
diff --git a/src/features/conversation/repositories/conversation.repository.ts b/src/features/conversation/repositories/conversation.repository.ts
index 71a1c9ae..f4e5f650 100644
--- a/src/features/conversation/repositories/conversation.repository.ts
+++ b/src/features/conversation/repositories/conversation.repository.ts
@@ -295,6 +295,35 @@ export class ConversationRepository {
     });
   }
 
+  /** 이벤트 payload용 매장명 단건 조회. */
+  async findStoreNameById(storeId: bigint) {
+    return this.prisma.store.findFirst({
+      where: { id: storeId, deleted_at: undefined },
+      select: { store_name: true },
+    });
+  }
+
+  /** subscription 구독 권한 판정용 — 대화 소유 구매자/해당 매장 판매자 확인. */
+  async findConversationAccess(conversationId: bigint) {
+    return this.prisma.storeConversation.findFirst({
+      where: { id: conversationId },
+      select: {
+        id: true,
+        account_id: true,
+        store_id: true,
+        store: { select: { seller_account_id: true } },
+      },
+    });
+  }
+
+  /** 판매자 구독 대상 매장(활성) 조회. */
+  async findStoreBySellerAccount(sellerAccountId: bigint) {
+    return this.prisma.store.findFirst({
+      where: { seller_account_id: sellerAccountId, ...activeWhere },
+      select: { id: true },
+    });
+  }
+
   /**
    * 구매자 메시지 저장. 대화가 없으면 같은 트랜잭션에서 생성하고, 인사말은
    * "대화의 첫 메시지"일 때만(메시지 0건) 유저 메시지보다 앞서 저장한다.
diff --git a/src/features/conversation/resolvers/conversation-center.resolver.spec.ts b/src/features/conversation/resolvers/conversation-center.resolver.spec.ts
index 825dd52c..765d571f 100644
--- a/src/features/conversation/resolvers/conversation-center.resolver.spec.ts
+++ b/src/features/conversation/resolvers/conversation-center.resolver.spec.ts
@@ -1,11 +1,14 @@
 // 전체 경로(리졸버→서비스→레포→DB) 통합 검증만 담당. 분기/집계 세부 검증은 service.spec.ts에서 담당
 import type { PrismaClient } from '@prisma/client';
+import { PubSub } from 'graphql-subscriptions';
 
 import { ConversationRepository } from '@/features/conversation/repositories/conversation.repository';
 import { ConversationCenterQueryResolver } from '@/features/conversation/resolvers/conversation-center-query.resolver';
 import { ConversationInquiryMutationResolver } from '@/features/conversation/resolvers/conversation-inquiry-mutation.resolver';
 import { ConversationCenterService } from '@/features/conversation/services/conversation-center.service';
+import { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
 import { ConversationInquiryService } from '@/features/conversation/services/conversation-inquiry.service';
+import { PUB_SUB } from '@/global/pubsub';
 import { disconnectTestPrismaClient } from '@/test/db/prisma-test-client';
 import { closeTruncateConnection, truncateAll } from '@/test/db/truncate';
 import {
@@ -28,6 +31,8 @@ describe('Conversation Center Resolvers (real DB)', () => {
         ConversationCenterService,
         ConversationInquiryService,
         ConversationRepository,
+        ConversationEventsService,
+        { provide: PUB_SUB, useValue: new PubSub() },
       ],
     });
     centerResolver = module.get(ConversationCenterQueryResolver);
diff --git a/src/features/conversation/resolvers/conversation-inquiry.resolver.spec.ts b/src/features/conversation/resolvers/conversation-inquiry.resolver.spec.ts
index 5663ba64..a992999d 100644
--- a/src/features/conversation/resolvers/conversation-inquiry.resolver.spec.ts
+++ b/src/features/conversation/resolvers/conversation-inquiry.resolver.spec.ts
@@ -1,10 +1,13 @@
 // 전체 경로(리졸버→서비스→레포→DB) 통합 검증만 담당. 분기·예외 세부는 service.spec.ts에서 담당
 import type { PrismaClient } from '@prisma/client';
+import { PubSub } from 'graphql-subscriptions';
 
 import { ConversationRepository } from '@/features/conversation/repositories/conversation.repository';
 import { ConversationInquiryMutationResolver } from '@/features/conversation/resolvers/conversation-inquiry-mutation.resolver';
 import { ConversationInquiryQueryResolver } from '@/features/conversation/resolvers/conversation-inquiry-query.resolver';
+import { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
 import { ConversationInquiryService } from '@/features/conversation/services/conversation-inquiry.service';
+import { PUB_SUB } from '@/global/pubsub';
 import { disconnectTestPrismaClient } from '@/test/db/prisma-test-client';
 import { closeTruncateConnection, truncateAll } from '@/test/db/truncate';
 import {
@@ -26,6 +29,8 @@ describe('Conversation Inquiry Resolvers (real DB)', () => {
         ConversationInquiryMutationResolver,
         ConversationInquiryService,
         ConversationRepository,
+        ConversationEventsService,
+        { provide: PUB_SUB, useValue: new PubSub() },
       ],
     });
     queryResolver = module.get(ConversationInquiryQueryResolver);
diff --git a/src/features/conversation/resolvers/conversation-subscription.resolver.ts b/src/features/conversation/resolvers/conversation-subscription.resolver.ts
new file mode 100644
index 00000000..d8a49a81
--- /dev/null
+++ b/src/features/conversation/resolvers/conversation-subscription.resolver.ts
@@ -0,0 +1,54 @@
+import { UseGuards } from '@nestjs/common';
+import { Args, Resolver, Subscription } from '@nestjs/graphql';
+
+import { ConversationSubscriptionService } from '@/features/conversation/services/conversation-subscription.service';
+import {
+  CurrentUser,
+  JwtAuthGuard,
+  parseAccountId,
+  type JwtUser,
+} from '@/global/auth';
+
+/**
+ * 이벤트 payload는 발행 시 이미 GraphQL 출력 형태로 조립돼 있어
+ * resolve는 payload를 그대로 통과시킨다.
+ */
+const passthrough = { resolve: (payload: unknown): unknown => payload };
+
+@Resolver('Subscription')
+@UseGuards(JwtAuthGuard)
+export class ConversationSubscriptionResolver {
+  constructor(
+    private readonly subscriptionService: ConversationSubscriptionService,
+  ) {}
+
+  @Subscription('conversationMessageAdded', passthrough)
+  conversationMessageAdded(
+    @CurrentUser() user: JwtUser,
+    @Args('conversationId') conversationId: string,
+  ): Promise<AsyncIterator<unknown>> {
+    const accountId = parseAccountId(user);
+    return this.subscriptionService.subscribeConversationMessages(
+      accountId,
+      conversationId,
+    );
+  }
+
+  @Subscription('myConversationUpdated', passthrough)
+  myConversationUpdated(
+    @CurrentUser() user: JwtUser,
+  ): Promise<AsyncIterator<unknown>> {
+    const accountId = parseAccountId(user);
+    return this.subscriptionService.subscribeMyConversationUpdates(accountId);
+  }
+
+  @Subscription('sellerConversationUpdated', passthrough)
+  sellerConversationUpdated(
+    @CurrentUser() user: JwtUser,
+  ): Promise<AsyncIterator<unknown>> {
+    const accountId = parseAccountId(user);
+    return this.subscriptionService.subscribeSellerConversationUpdates(
+      accountId,
+    );
+  }
+}
diff --git a/src/features/conversation/services/conversation-events-mappers.helper.spec.ts b/src/features/conversation/services/conversation-events-mappers.helper.spec.ts
new file mode 100644
index 00000000..ef9fec7d
--- /dev/null
+++ b/src/features/conversation/services/conversation-events-mappers.helper.spec.ts
@@ -0,0 +1,47 @@
+import {
+  toConversationMessageEvent,
+  toEventPreview,
+} from '@/features/conversation/services/conversation-events-mappers.helper';
+import type { ConversationMessageOutput } from '@/features/conversation/types/conversation-output.type';
+
+function message(
+  overrides: Partial<ConversationMessageOutput> = {},
+): ConversationMessageOutput {
+  return {
+    id: '1',
+    conversationId: '2',
+    senderType: 'USER',
+    bodyFormat: 'TEXT',
+    bodyText: '안녕하세요',
+    bodyHtml: null,
+    createdAt: new Date('2026-08-01T12:00:00Z'),
+    ...overrides,
+  };
+}
+
+describe('conversation-events-mappers.helper', () => {
+  it('메시지 출력의 날짜를 ISO 문자열로 바꿔 이벤트 payload를 만든다', () => {
+    expect(toConversationMessageEvent(message())).toEqual({
+      id: '1',
+      conversationId: '2',
+      senderType: 'USER',
+      bodyFormat: 'TEXT',
+      bodyText: '안녕하세요',
+      bodyHtml: null,
+      createdAt: '2026-08-01T12:00:00.000Z',
+    });
+  });
+
+  it('미리보기는 TEXT 원문 / HTML 태그 제거 텍스트를 쓴다', () => {
+    expect(toEventPreview(message())).toBe('안녕하세요');
+    expect(
+      toEventPreview(
+        message({
+          bodyFormat: 'HTML',
+          bodyText: null,
+          bodyHtml: '<p>자동 <b>응답</b></p>',
+        }),
+      ),
+    ).toBe('자동 응답');
+  });
+});
diff --git a/src/features/conversation/services/conversation-events-mappers.helper.ts b/src/features/conversation/services/conversation-events-mappers.helper.ts
new file mode 100644
index 00000000..ad16bbc3
--- /dev/null
+++ b/src/features/conversation/services/conversation-events-mappers.helper.ts
@@ -0,0 +1,33 @@
+import { toLastMessagePreview } from '@/features/conversation/services/conversation-center-mappers.helper';
+import type {
+  ConversationMessageEvent,
+  ConversationMessageOutput,
+} from '@/features/conversation/types/conversation-output.type';
+
+/** DI-free 순수 함수만 둔다 — subscription 이벤트 payload 변환. */
+
+/** 메시지 출력 → 이벤트 payload(날짜는 ISO 문자열). */
+export function toConversationMessageEvent(
+  message: ConversationMessageOutput,
+): ConversationMessageEvent {
+  return {
+    id: message.id,
+    conversationId: message.conversationId,
+    senderType: message.senderType,
+    bodyFormat: message.bodyFormat,
+    bodyText: message.bodyText,
+    bodyHtml: message.bodyHtml,
+    createdAt: message.createdAt.toISOString(),
+  };
+}
+
+/** 메시지 출력 → 목록 이벤트용 미리보기 텍스트. */
+export function toEventPreview(
+  message: ConversationMessageOutput,
+): string | null {
+  return toLastMessagePreview({
+    body_format: message.bodyFormat,
+    body_text: message.bodyText,
+    body_html: message.bodyHtml,
+  });
+}
diff --git a/src/features/conversation/services/conversation-events.service.spec.ts b/src/features/conversation/services/conversation-events.service.spec.ts
new file mode 100644
index 00000000..3a1709a0
--- /dev/null
+++ b/src/features/conversation/services/conversation-events.service.spec.ts
@@ -0,0 +1,116 @@
+/**
+ * 실 Redis(testcontainers) 기반 발행/구독 왕복 검증 — JSON 직렬화를 거친
+ * payload가 구독자에게 그대로 도착하는지까지 확인한다(DB 불필요).
+ */
+import { RedisPubSub } from 'graphql-redis-subscriptions';
+import Redis from 'ioredis';
+import { GenericContainer, type StartedTestContainer } from 'testcontainers';
+
+import { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
+import type { ConversationMessageOutput } from '@/features/conversation/types/conversation-output.type';
+
+jest.setTimeout(180_000);
+
+describe('ConversationEventsService (real Redis)', () => {
+  let container: StartedTestContainer;
+  let pubSub: RedisPubSub;
+  let service: ConversationEventsService;
+
+  beforeAll(async () => {
+    container = await new GenericContainer('redis:7-alpine')
+      .withExposedPorts(6379)
+      .start();
+    const url = `redis://${container.getHost()}:${container.getMappedPort(6379)}`;
+    pubSub = new RedisPubSub({
+      publisher: new Redis(url),
+      subscriber: new Redis(url),
+    });
+    service = new ConversationEventsService(pubSub);
+  });
+
+  afterAll(async () => {
+    await pubSub.close();
+    await container.stop();
+  });
+
+  async function nextEvent(iterator: AsyncIterator<unknown>) {
+    return (await iterator.next()).value;
+  }
+
+  /**
+   * asyncIterableIterator는 첫 next() 호출 시점에 Redis SUBSCRIBE를 보낸다 —
+   * 발행 전에 next()를 먼저 걸고 SUBSCRIBE 완료를 잠깐 기다려야 이벤트를
+   * 놓치지 않는다(구독 등록 전 발행분은 유실되는 게 Pub/Sub 의미론).
+   */
+  async function startListening(iterator: AsyncIterator<unknown>) {
+    const pending = nextEvent(iterator);
+    await new Promise((resolve) => setTimeout(resolve, 300));
+    // Promise를 그대로 반환하면 호출부의 await가 이벤트 도착까지 평탄화해
+    // 기다려 버린다 — 객체로 감싸 구독 시작만 보장하고 대기는 호출부 몫으로.
+    return { pending };
+  }
+
+  it('대화방 메시지 발행이 해당 대화 구독자에게만 도착한다', async () => {
+    const target = service.messageAddedIterator('10');
+    const other = service.messageAddedIterator('99');
+    const { pending: pendingTarget } = await startListening(target);
+    const otherReceived = jest.fn();
+    const { pending: pendingOther } = await startListening(other);
+    void pendingOther.then(otherReceived);
+
+    const message: ConversationMessageOutput = {
+      id: '1',
+      conversationId: '10',
+      senderType: 'USER',
+      bodyFormat: 'TEXT',
+      bodyText: '픽업 문의',
+      bodyHtml: null,
+      createdAt: new Date('2026-08-01T12:00:00Z'),
+    };
+    await service.publishMessagesAdded([message]);
+
+    // Redis JSON 왕복 후에도 이벤트 payload가 보존된다(날짜는 ISO 문자열)
+    await expect(pendingTarget).resolves.toEqual({
+      id: '1',
+      conversationId: '10',
+      senderType: 'USER',
+      bodyFormat: 'TEXT',
+      bodyText: '픽업 문의',
+      bodyHtml: null,
+      createdAt: '2026-08-01T12:00:00.000Z',
+    });
+    expect(otherReceived).not.toHaveBeenCalled();
+    await other.return?.();
+  });
+
+  it('구매자/판매자 목록 갱신 이벤트가 각 토픽으로 도착한다', async () => {
+    const buyer = service.buyerListIterator('7');
+    const seller = service.sellerListIterator('3');
+    const { pending: pendingBuyer } = await startListening(buyer);
+    const { pending: pendingSeller } = await startListening(seller);
+
+    await service.publishBuyerListUpdate('7', {
+      conversationId: '10',
+      storeId: '3',
+      storeName: '해즈 케이크',
+      lastMessagePreview: '답변 드리겠습니다',
+      lastMessageAt: '2026-08-01T12:00:00.000Z',
+      unreadCount: 2,
+    });
+    await service.publishSellerListUpdate('3', {
+      conversationId: '10',
+      accountId: '7',
+      lastMessagePreview: '픽업 문의',
+      lastMessageAt: '2026-08-01T12:00:00.000Z',
+    });
+
+    await expect(pendingBuyer).resolves.toMatchObject({
+      storeName: '해즈 케이크',
+      unreadCount: 2,
+    });
+    await expect(pendingSeller).resolves.toMatchObject({
+      accountId: '7',
+      lastMessagePreview: '픽업 문의',
+    });
+  });
+});
diff --git a/src/features/conversation/services/conversation-events.service.ts b/src/features/conversation/services/conversation-events.service.ts
new file mode 100644
index 00000000..0b401721
--- /dev/null
+++ b/src/features/conversation/services/conversation-events.service.ts
@@ -0,0 +1,70 @@
+import { Inject, Injectable } from '@nestjs/common';
+import type { PubSubEngine } from 'graphql-subscriptions';
+
+import { toConversationMessageEvent } from '@/features/conversation/services/conversation-events-mappers.helper';
+import type {
+  ConversationListUpdateEvent,
+  ConversationMessageOutput,
+  SellerConversationListUpdateEvent,
+} from '@/features/conversation/types/conversation-output.type';
+import { PUB_SUB } from '@/global/pubsub';
+
+/**
+ * 대화 subscription 이벤트 발행/구독 어댑터.
+ * 토픽 문자열은 여기서만 조립한다 — 발행자(구매자 전송·FAQ 자동응답·판매자
+ * 답장)와 구독 리졸버가 같은 토픽을 보게 하는 단일 소스.
+ */
+@Injectable()
+export class ConversationEventsService {
+  constructor(@Inject(PUB_SUB) private readonly pubSub: PubSubEngine) {}
+
+  private messageTopic(conversationId: string): string {
+    return `conversation.message.${conversationId}`;
+  }
+
+  private buyerTopic(accountId: string): string {
+    return `conversation.buyer.${accountId}`;
+  }
+
+  private sellerTopic(storeId: string): string {
+    return `conversation.seller.${storeId}`;
+  }
+
+  /** 저장된 메시지들을 대화방 토픽에 순서대로 발행한다. */
+  async publishMessagesAdded(
+    messages: ConversationMessageOutput[],
+  ): Promise<void> {
+    for (const message of messages) {
+      await this.pubSub.publish(
+        this.messageTopic(message.conversationId),
+        toConversationMessageEvent(message),
+      );
+    }
+  }
+
+  async publishBuyerListUpdate(
+    accountId: string,
+    event: ConversationListUpdateEvent,
+  ): Promise<void> {
+    await this.pubSub.publish(this.buyerTopic(accountId), event);
+  }
+
+  async publishSellerListUpdate(
+    storeId: string,
+    event: SellerConversationListUpdateEvent,
+  ): Promise<void> {
+    await this.pubSub.publish(this.sellerTopic(storeId), event);
+  }
+
+  messageAddedIterator(conversationId: string): AsyncIterator<unknown> {
+    return this.pubSub.asyncIterableIterator(this.messageTopic(conversationId));
+  }
+
+  buyerListIterator(accountId: string): AsyncIterator<unknown> {
+    return this.pubSub.asyncIterableIterator(this.buyerTopic(accountId));
+  }
+
+  sellerListIterator(storeId: string): AsyncIterator<unknown> {
+    return this.pubSub.asyncIterableIterator(this.sellerTopic(storeId));
+  }
+}
diff --git a/src/features/conversation/services/conversation-inquiry.service.spec.ts b/src/features/conversation/services/conversation-inquiry.service.spec.ts
index 75d0c94e..3db802fd 100644
--- a/src/features/conversation/services/conversation-inquiry.service.spec.ts
+++ b/src/features/conversation/services/conversation-inquiry.service.spec.ts
@@ -5,9 +5,12 @@ import {
   UnauthorizedException,
 } from '@nestjs/common';
 import type { PrismaClient } from '@prisma/client';
+import { PubSub } from 'graphql-subscriptions';
 
 import { ConversationRepository } from '@/features/conversation/repositories/conversation.repository';
+import { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
 import { ConversationInquiryService } from '@/features/conversation/services/conversation-inquiry.service';
+import { PUB_SUB } from '@/global/pubsub';
 import { disconnectTestPrismaClient } from '@/test/db/prisma-test-client';
 import { closeTruncateConnection, truncateAll } from '@/test/db/truncate';
 import {
@@ -23,7 +26,13 @@ describe('ConversationInquiryService (real DB)', () => {
 
   beforeAll(async () => {
     const { module, prisma: p } = await createTestingModuleWithRealDb({
-      providers: [ConversationInquiryService, ConversationRepository],
+      providers: [
+        ConversationInquiryService,
+        ConversationRepository,
+        ConversationEventsService,
+        // 발행 경로 실검증은 events service spec(실 Redis) 담당 — 여기선 in-memory
+        { provide: PUB_SUB, useValue: new PubSub() },
+      ],
     });
     service = module.get(ConversationInquiryService);
     prisma = p;
diff --git a/src/features/conversation/services/conversation-inquiry.service.ts b/src/features/conversation/services/conversation-inquiry.service.ts
index a64a9f0d..1f735fc2 100644
--- a/src/features/conversation/services/conversation-inquiry.service.ts
+++ b/src/features/conversation/services/conversation-inquiry.service.ts
@@ -12,6 +12,8 @@ import {
   type ConversationMessageEntry,
 } from '@/features/conversation/repositories/conversation.repository';
 import { ConversationBaseService } from '@/features/conversation/services/conversation-base.service';
+import { toEventPreview } from '@/features/conversation/services/conversation-events-mappers.helper';
+import { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
 import {
   renderGreeting,
   toConversationMessageOutput,
@@ -24,7 +26,10 @@ import type {
 
 @Injectable()
 export class ConversationInquiryService extends ConversationBaseService {
-  constructor(repo: ConversationRepository) {
+  constructor(
+    repo: ConversationRepository,
+    private readonly events: ConversationEventsService,
+  ) {
     super(repo);
   }
 
@@ -151,12 +156,66 @@ export class ConversationInquiryService extends ConversationBaseService {
       entries: args.entries,
     });
 
+    const messages = result.messages.map(toConversationMessageOutput);
+    await this.publishBuyerSendEvents({
+      accountId: args.accountId,
+      storeId: args.storeId,
+      storeName: args.storeName,
+      conversationId: result.conversationId,
+      messages,
+    });
+
     return {
       conversationId: result.conversationId.toString(),
-      messages: result.messages.map(toConversationMessageOutput),
+      messages,
     };
   }
 
+  /**
+   * 실시간 이벤트 발행 — 대화방 메시지 + 양측 목록/배지 갱신.
+   * 저장 트랜잭션 밖의 부수효과라 실패해도 전송 자체는 성공으로 남는다
+   * (구독자는 폴백 재조회 가능).
+   */
+  private async publishBuyerSendEvents(args: {
+    accountId: bigint;
+    storeId: bigint;
+    storeName: string;
+    conversationId: bigint;
+    messages: ConversationMessagesPayload['messages'];
+  }): Promise<void> {
+    const lastMessage = args.messages[args.messages.length - 1];
+    if (!lastMessage) return;
+    // 시각은 repository가 잠금 아래 채번한 저장 시각을 그대로 쓴다
+    const lastMessageAtIso = lastMessage.createdAt.toISOString();
+
+    const conversation = await this.repo.findConversationByAccountAndStore({
+      accountId: args.accountId,
+      storeId: args.storeId,
+    });
+    const [extras] = conversation
+      ? await this.repo.getConversationListExtras([
+          { id: conversation.id, last_read_at: conversation.last_read_at },
+        ])
+      : [undefined];
+
+    const preview = toEventPreview(lastMessage);
+    await this.events.publishMessagesAdded(args.messages);
+    await this.events.publishBuyerListUpdate(args.accountId.toString(), {
+      conversationId: args.conversationId.toString(),
+      storeId: args.storeId.toString(),
+      storeName: args.storeName,
+      lastMessagePreview: preview,
+      lastMessageAt: lastMessageAtIso,
+      unreadCount: extras?.unreadCount ?? 0,
+    });
+    await this.events.publishSellerListUpdate(args.storeId.toString(), {
+      conversationId: args.conversationId.toString(),
+      accountId: args.accountId.toString(),
+      lastMessagePreview: preview,
+      lastMessageAt: lastMessageAtIso,
+    });
+  }
+
   private async requireInquiryStore(storeId: bigint) {
     const store = await this.repo.findInquiryStore(storeId);
     if (!store) {
diff --git a/src/features/conversation/services/conversation-subscription.service.spec.ts b/src/features/conversation/services/conversation-subscription.service.spec.ts
new file mode 100644
index 00000000..8d9c7c65
--- /dev/null
+++ b/src/features/conversation/services/conversation-subscription.service.spec.ts
@@ -0,0 +1,180 @@
+import {
+  ForbiddenException,
+  NotFoundException,
+  UnauthorizedException,
+} from '@nestjs/common';
+import type { PrismaClient } from '@prisma/client';
+import { PubSub } from 'graphql-subscriptions';
+
+import { ConversationRepository } from '@/features/conversation/repositories/conversation.repository';
+import { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
+import { ConversationInquiryService } from '@/features/conversation/services/conversation-inquiry.service';
+import { ConversationSubscriptionService } from '@/features/conversation/services/conversation-subscription.service';
+import { PUB_SUB } from '@/global/pubsub';
+import { disconnectTestPrismaClient } from '@/test/db/prisma-test-client';
+import { closeTruncateConnection, truncateAll } from '@/test/db/truncate';
+import {
+  createAccount,
+  createStore,
+  createUserProfile,
+} from '@/test/factories';
+import { createTestingModuleWithRealDb } from '@/test/modules/testing-module.builder';
+
+describe('ConversationSubscriptionService (real DB)', () => {
+  let service: ConversationSubscriptionService;
+  let inquiryService: ConversationInquiryService;
+  let prisma: PrismaClient;
+
+  beforeAll(async () => {
+    const { module, prisma: p } = await createTestingModuleWithRealDb({
+      providers: [
+        ConversationSubscriptionService,
+        ConversationInquiryService,
+        ConversationEventsService,
+        ConversationRepository,
+        // 발행-구독 왕복은 실 Redis spec(events service) 담당 — 여기선 in-memory
+        { provide: PUB_SUB, useValue: new PubSub() },
+      ],
+    });
+    service = module.get(ConversationSubscriptionService);
+    inquiryService = module.get(ConversationInquiryService);
+    prisma = p;
+  });
+
+  afterAll(async () => {
+    await closeTruncateConnection();
+    await disconnectTestPrismaClient();
+  });
+
+  beforeEach(async () => {
+    await truncateAll();
+  });
+
+  async function setupBuyer() {
+    const account = await createAccount(prisma, { account_type: 'USER' });
+    await createUserProfile(prisma, { account_id: account.id });
+    return account;
+  }
+
+  describe('subscribeConversationMessages', () => {
+    it('대화 소유 구매자와 해당 매장 판매자는 구독할 수 있고, 제3자는 NotFound', async () => {
+      const buyer = await setupBuyer();
+      const stranger = await setupBuyer();
+      const seller = await createAccount(prisma, { account_type: 'SELLER' });
+      const store = await createStore(prisma, {
+        seller_account_id: seller.id,
+      });
+      const conversation = await prisma.storeConversation.create({
+        data: { account_id: buyer.id, store_id: store.id },
+      });
+      const id = conversation.id.toString();
+
+      await expect(
+        service.subscribeConversationMessages(buyer.id, id),
+      ).resolves.toBeDefined();
+      await expect(
+        service.subscribeConversationMessages(seller.id, id),
+      ).resolves.toBeDefined();
+      await expect(
+        service.subscribeConversationMessages(stranger.id, id),
+      ).rejects.toThrow(NotFoundException);
+      await expect(
+        service.subscribeConversationMessages(buyer.id, '999999'),
+      ).rejects.toThrow(NotFoundException);
+    });
+
+    it('구독 중이면 구매자 전송 이벤트를 실제로 수신한다(발행 경로 통합)', async () => {
+      const buyer = await setupBuyer();
+      const store = await createStore(prisma, { store_name: '해즈 케이크' });
+
+      // 첫 전송으로 대화 생성 → 그 대화를 구독 → 두 번째 전송 수신 확인
+      const first = await inquiryService.sendConversationMessage(buyer.id, {
+        storeId: store.id.toString(),
+        bodyText: '첫 문의',
+      });
+      const iterator = await service.subscribeConversationMessages(
+        buyer.id,
+        first.conversationId,
+      );
+      const pending = iterator.next();
+
+      await inquiryService.sendConversationMessage(buyer.id, {
+        storeId: store.id.toString(),
+        bodyText: '추가 문의',
+      });
+
+      const { value } = await pending;
+      expect(value).toMatchObject({
+        conversationId: first.conversationId,
+        senderType: 'USER',
+        bodyText: '추가 문의',
+      });
+      await iterator.return?.();
+    });
+  });
+
+  describe('subscribeMyConversationUpdates', () => {
+    it('활성 USER만 구독 가능하고, 전송 시 목록 갱신 이벤트를 수신한다', async () => {
+      const buyer = await setupBuyer();
+      const seller = await createAccount(prisma, { account_type: 'SELLER' });
+      const store = await createStore(prisma, { store_name: '달콤 케이크' });
+
+      await expect(
+        service.subscribeMyConversationUpdates(BigInt(999999)),
+      ).rejects.toThrow(UnauthorizedException);
+      await expect(
+        service.subscribeMyConversationUpdates(seller.id),
+      ).rejects.toThrow(ForbiddenException);
+
+      const iterator = await service.subscribeMyConversationUpdates(buyer.id);
+      const pending = iterator.next();
+
+      await inquiryService.sendConversationMessage(buyer.id, {
+        storeId: store.id.toString(),
+        bodyText: '문의합니다',
+      });
+
+      const { value } = await pending;
+      expect(value).toMatchObject({
+        storeId: store.id.toString(),
+        storeName: '달콤 케이크',
+        lastMessagePreview: '문의합니다',
+        // 인사말은 mutation 응답으로 즉시 표시돼 읽음 처리된다
+        unreadCount: 0,
+      });
+      await iterator.return?.();
+    });
+  });
+
+  describe('subscribeSellerConversationUpdates', () => {
+    it('매장 보유 판매자만 구독 가능하고, 고객 전송 이벤트를 수신한다', async () => {
+      const buyer = await setupBuyer();
+      const seller = await createAccount(prisma, { account_type: 'SELLER' });
+      const store = await createStore(prisma, {
+        seller_account_id: seller.id,
+      });
+
+      // 매장 없는 계정은 구독 불가
+      await expect(
+        service.subscribeSellerConversationUpdates(buyer.id),
+      ).rejects.toThrow(NotFoundException);
+
+      const iterator = await service.subscribeSellerConversationUpdates(
+        seller.id,
+      );
+      const pending = iterator.next();
+
+      await inquiryService.sendConversationMessage(buyer.id, {
+        storeId: store.id.toString(),
+        bodyText: '픽업 시간 문의',
+      });
+
+      const { value } = await pending;
+      expect(value).toMatchObject({
+        accountId: buyer.id.toString(),
+        lastMessagePreview: '픽업 시간 문의',
+      });
+      await iterator.return?.();
+    });
+  });
+});
diff --git a/src/features/conversation/services/conversation-subscription.service.ts b/src/features/conversation/services/conversation-subscription.service.ts
new file mode 100644
index 00000000..cfa61147
--- /dev/null
+++ b/src/features/conversation/services/conversation-subscription.service.ts
@@ -0,0 +1,60 @@
+import { Injectable, NotFoundException } from '@nestjs/common';
+
+import { parseId } from '@/common/utils/id-parser';
+import { CONVERSATION_ERRORS } from '@/features/conversation/constants/conversation-error-messages';
+import { ConversationRepository } from '@/features/conversation/repositories/conversation.repository';
+import { ConversationBaseService } from '@/features/conversation/services/conversation-base.service';
+import { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
+
+/**
+ * subscription 구독 진입점 — 구독 권한 검증 후 토픽 iterator를 돌려준다.
+ * 이벤트 발행은 각 전송 서비스(구매자 전송·판매자 답장)가 담당한다.
+ */
+@Injectable()
+export class ConversationSubscriptionService extends ConversationBaseService {
+  constructor(
+    repo: ConversationRepository,
+    private readonly events: ConversationEventsService,
+  ) {
+    super(repo);
+  }
+
+  /** 대화방 메시지 구독 — 대화 소유 구매자 또는 해당 매장 판매자만. */
+  async subscribeConversationMessages(
+    accountId: bigint,
+    conversationIdRaw: string,
+  ): Promise<AsyncIterator<unknown>> {
+    const conversationId = parseId(conversationIdRaw);
+    const conversation = await this.repo.findConversationAccess(conversationId);
+
+    // 존재하지 않는 대화와 권한 없는 대화를 구분하지 않는다(존재 여부 노출 방지)
+    const allowed =
+      conversation &&
+      (conversation.account_id === accountId ||
+        conversation.store.seller_account_id === accountId);
+    if (!allowed) {
+      throw new NotFoundException(CONVERSATION_ERRORS.CONVERSATION_NOT_FOUND);
+    }
+
+    return this.events.messageAddedIterator(conversationId.toString());
+  }
+
+  /** 구매자 대화 목록/배지 갱신 구독. */
+  async subscribeMyConversationUpdates(
+    accountId: bigint,
+  ): Promise<AsyncIterator<unknown>> {
+    await this.requireActiveUser(accountId);
+    return this.events.buyerListIterator(accountId.toString());
+  }
+
+  /** 판매자 대화 목록 갱신 구독. */
+  async subscribeSellerConversationUpdates(
+    accountId: bigint,
+  ): Promise<AsyncIterator<unknown>> {
+    const store = await this.repo.findStoreBySellerAccount(accountId);
+    if (!store) {
+      throw new NotFoundException(CONVERSATION_ERRORS.STORE_NOT_FOUND);
+    }
+    return this.events.sellerListIterator(store.id.toString());
+  }
+}
diff --git a/src/features/conversation/types/conversation-output.type.ts b/src/features/conversation/types/conversation-output.type.ts
index aa04943e..8581eb54 100644
--- a/src/features/conversation/types/conversation-output.type.ts
+++ b/src/features/conversation/types/conversation-output.type.ts
@@ -63,3 +63,33 @@ export interface ConversationMessageConnection {
   hasMore: boolean;
   nextCursor: string | null;
 }
+
+/**
+ * subscription 이벤트 payload — Redis JSON 직렬화를 거치므로 날짜는 ISO
+ * 문자열로 나른다(DateTime 스칼라가 문자열도 직렬화 가능).
+ */
+export interface ConversationMessageEvent {
+  id: string;
+  conversationId: string;
+  senderType: ConversationSenderType;
+  bodyFormat: ConversationBodyFormat;
+  bodyText: string | null;
+  bodyHtml: string | null;
+  createdAt: string;
+}
+
+export interface ConversationListUpdateEvent {
+  conversationId: string;
+  storeId: string;
+  storeName: string;
+  lastMessagePreview: string | null;
+  lastMessageAt: string;
+  unreadCount: number;
+}
+
+export interface SellerConversationListUpdateEvent {
+  conversationId: string;
+  accountId: string;
+  lastMessagePreview: string | null;
+  lastMessageAt: string;
+}
diff --git a/src/features/core/root.graphql b/src/features/core/root.graphql
index c74beee4..f956249f 100644
--- a/src/features/core/root.graphql
+++ b/src/features/core/root.graphql
@@ -12,3 +12,8 @@ type Mutation {
   """스키마 루트 유지를 위한 no-op 필드"""
   _noop: Boolean
 }
+
+type Subscription {
+  """스키마 루트 유지를 위한 no-op 필드"""
+  _subscriptionNoop: Boolean
+}
diff --git a/src/features/seller/resolvers/seller-conversation.resolver.spec.ts b/src/features/seller/resolvers/seller-conversation.resolver.spec.ts
index 4eac2235..559631d2 100644
--- a/src/features/seller/resolvers/seller-conversation.resolver.spec.ts
+++ b/src/features/seller/resolvers/seller-conversation.resolver.spec.ts
@@ -1,13 +1,16 @@
 import { NotFoundException } from '@nestjs/common';
 import type { PrismaClient } from '@prisma/client';
+import { PubSub } from 'graphql-subscriptions';
 
 import { AUDIT_LOG_REPOSITORY } from '@/features/audit-log';
 import { AuditLogRepository } from '@/features/audit-log/repositories/audit-log.repository';
 import { ConversationRepository } from '@/features/conversation';
+import { ConversationEventsService } from '@/features/conversation';
 import { SellerRepository } from '@/features/seller/repositories/seller.repository';
 import { SellerConversationMutationResolver } from '@/features/seller/resolvers/seller-conversation-mutation.resolver';
 import { SellerConversationQueryResolver } from '@/features/seller/resolvers/seller-conversation-query.resolver';
 import { SellerConversationService } from '@/features/seller/services/seller-conversation.service';
+import { PUB_SUB } from '@/global/pubsub';
 import { disconnectTestPrismaClient } from '@/test/db/prisma-test-client';
 import { closeTruncateConnection, truncateAll } from '@/test/db/truncate';
 import { createAccount, setupSellerWithStore } from '@/test/factories';
@@ -26,6 +29,8 @@ describe('Seller Conversation Resolvers (real DB)', () => {
         SellerConversationService,
         SellerRepository,
         ConversationRepository,
+        ConversationEventsService,
+        { provide: PUB_SUB, useValue: new PubSub() },
         {
           provide: AUDIT_LOG_REPOSITORY,
           useClass: AuditLogRepository,
diff --git a/src/features/seller/services/seller-conversation.service.spec.ts b/src/features/seller/services/seller-conversation.service.spec.ts
index 8ae22cdd..98ea43ba 100644
--- a/src/features/seller/services/seller-conversation.service.spec.ts
+++ b/src/features/seller/services/seller-conversation.service.spec.ts
@@ -1,11 +1,14 @@
 import { BadRequestException, NotFoundException } from '@nestjs/common';
 import type { PrismaClient } from '@prisma/client';
+import { PubSub } from 'graphql-subscriptions';
 
 import { AUDIT_LOG_REPOSITORY } from '@/features/audit-log';
 import { AuditLogRepository } from '@/features/audit-log/repositories/audit-log.repository';
 import { ConversationRepository } from '@/features/conversation';
+import { ConversationEventsService } from '@/features/conversation';
 import { SellerRepository } from '@/features/seller/repositories/seller.repository';
 import { SellerConversationService } from '@/features/seller/services/seller-conversation.service';
+import { PUB_SUB } from '@/global/pubsub';
 import { disconnectTestPrismaClient } from '@/test/db/prisma-test-client';
 import { closeTruncateConnection, truncateAll } from '@/test/db/truncate';
 import { createAccount, setupSellerWithStore } from '@/test/factories';
@@ -21,6 +24,8 @@ describe('SellerConversationService (real DB)', () => {
         SellerConversationService,
         SellerRepository,
         ConversationRepository,
+        ConversationEventsService,
+        { provide: PUB_SUB, useValue: new PubSub() },
         {
           provide: AUDIT_LOG_REPOSITORY,
           useClass: AuditLogRepository,
diff --git a/src/features/seller/services/seller-conversation.service.ts b/src/features/seller/services/seller-conversation.service.ts
index e0401dec..892cbb34 100644
--- a/src/features/seller/services/seller-conversation.service.ts
+++ b/src/features/seller/services/seller-conversation.service.ts
@@ -16,7 +16,11 @@ import {
   AUDIT_LOG_REPOSITORY,
   type IAuditLogRepository,
 } from '@/features/audit-log';
-import { ConversationRepository } from '@/features/conversation';
+import {
+  ConversationEventsService,
+  ConversationRepository,
+  toEventPreview,
+} from '@/features/conversation';
 import {
   BODY_HTML_REQUIRED,
   BODY_TEXT_REQUIRED,
@@ -48,6 +52,7 @@ export class SellerConversationService extends SellerBaseService {
     @Inject(AUDIT_LOG_REPOSITORY)
     auditLogs: IAuditLogRepository,
     private readonly conversationRepository: ConversationRepository,
+    private readonly conversationEvents: ConversationEventsService,
   ) {
     super(repo, auditLogs);
   }
@@ -156,7 +161,72 @@ export class SellerConversationService extends SellerBaseService {
       },
     });
 
-    return this.toConversationMessageOutput(row);
+    const output = this.toConversationMessageOutput(row);
+    await this.publishSellerReplyEvents({
+      conversation,
+      storeId: ctx.storeId,
+      message: output,
+    });
+
+    return output;
+  }
+
+  /**
+   * 실시간 이벤트 발행 — 대화방 메시지 + 구매자·판매자 목록 갱신.
+   * 저장 트랜잭션 밖의 부수효과라 실패해도 답장 자체는 성공으로 남는다.
+   */
+  private async publishSellerReplyEvents(args: {
+    conversation: {
+      id: bigint;
+      account_id: bigint;
+      last_read_at: Date | null;
+    };
+    storeId: bigint;
+    message: SellerConversationMessageOutput;
+  }): Promise<void> {
+    const message = {
+      id: args.message.id,
+      conversationId: args.message.conversationId,
+      senderType: args.message.senderType,
+      bodyFormat: args.message.bodyFormat,
+      bodyText: args.message.bodyText,
+      bodyHtml: args.message.bodyHtml,
+      createdAt: args.message.createdAt,
+    };
+    const preview = toEventPreview(message);
+    const lastMessageAtIso = args.message.createdAt.toISOString();
+
+    const [store, [extras]] = await Promise.all([
+      this.conversationRepository.findStoreNameById(args.storeId),
+      this.conversationRepository.getConversationListExtras([
+        {
+          id: args.conversation.id,
+          last_read_at: args.conversation.last_read_at,
+        },
+      ]),
+    ]);
+
+    await this.conversationEvents.publishMessagesAdded([message]);
+    await this.conversationEvents.publishBuyerListUpdate(
+      args.conversation.account_id.toString(),
+      {
+        conversationId: args.conversation.id.toString(),
+        storeId: args.storeId.toString(),
+        storeName: store?.store_name ?? '',
+        lastMessagePreview: preview,
+        lastMessageAt: lastMessageAtIso,
+        unreadCount: extras?.unreadCount ?? 0,
+      },
+    );
+    await this.conversationEvents.publishSellerListUpdate(
+      args.storeId.toString(),
+      {
+        conversationId: args.conversation.id.toString(),
+        accountId: args.conversation.account_id.toString(),
+        lastMessagePreview: preview,
+        lastMessageAt: lastMessageAtIso,
+      },
+    );
   }
 
   private toConversationBodyFormat(raw: string): ConversationBodyFormat {
diff --git a/src/global/graphql/graphql-context.helper.spec.ts b/src/global/graphql/graphql-context.helper.spec.ts
new file mode 100644
index 00000000..8a69e3af
--- /dev/null
+++ b/src/global/graphql/graphql-context.helper.spec.ts
@@ -0,0 +1,39 @@
+import type { IncomingMessage } from 'node:http';
+
+import type { Request, Response } from 'express';
+
+import { buildGraphqlContext } from '@/global/graphql/graphql-context.helper';
+
+describe('buildGraphqlContext', () => {
+  it('HTTP 요청은 req/res를 그대로 전달한다', () => {
+    const req = { headers: {} } as Request;
+    const res = {} as Response;
+
+    expect(buildGraphqlContext({ req, res })).toEqual({ req, res });
+  });
+
+  it('ws 연결은 connectionParams.authorization을 헤더로 이식한다', () => {
+    const request = { headers: { host: 'localhost' } } as IncomingMessage;
+
+    const ctx = buildGraphqlContext({
+      extra: { request },
+      connectionParams: { authorization: 'Bearer token-123' },
+    });
+
+    expect(ctx.req).toBe(request);
+    expect(request.headers.authorization).toBe('Bearer token-123');
+    expect(request.headers.host).toBe('localhost');
+  });
+
+  it('authorization이 없거나 문자열이 아니면 헤더를 건드리지 않는다', () => {
+    const request = { headers: {} } as IncomingMessage;
+
+    buildGraphqlContext({
+      extra: { request },
+      connectionParams: { authorization: 123 },
+    });
+    buildGraphqlContext({ extra: { request } });
+
+    expect(request.headers.authorization).toBeUndefined();
+  });
+});
diff --git a/src/global/graphql/graphql-context.helper.ts b/src/global/graphql/graphql-context.helper.ts
new file mode 100644
index 00000000..bb39112e
--- /dev/null
+++ b/src/global/graphql/graphql-context.helper.ts
@@ -0,0 +1,34 @@
+import type { IncomingMessage } from 'node:http';
+
+import type { Request, Response } from 'express';
+
+/**
+ * HTTP·WebSocket(graphql-ws) 공용 GraphQL context 조립.
+ *
+ * ws 연결의 인증 토큰은 connectionParams.authorization으로 들어오므로,
+ * upgrade 요청 객체에 HTTP 헤더 형태로 이식해 기존 JwtAuthGuard/passport
+ * 경로(req.headers.authorization)를 그대로 태운다 — 가드 이원화 방지.
+ */
+export interface GraphqlContextArgs {
+  req?: Request;
+  res?: Response;
+  extra?: { request?: IncomingMessage };
+  connectionParams?: Record<string, unknown>;
+}
+
+export interface GraphqlContext {
+  req: Request | IncomingMessage | undefined;
+  res?: Response;
+}
+
+export function buildGraphqlContext(ctx: GraphqlContextArgs): GraphqlContext {
+  const wsRequest = ctx?.extra?.request;
+  if (wsRequest) {
+    const authorization = ctx.connectionParams?.authorization;
+    if (typeof authorization === 'string' && authorization.length > 0) {
+      wsRequest.headers = { ...wsRequest.headers, authorization };
+    }
+    return { req: wsRequest };
+  }
+  return { req: ctx?.req, res: ctx?.res };
+}
diff --git a/src/global/pubsub/index.ts b/src/global/pubsub/index.ts
new file mode 100644
index 00000000..1f881398
--- /dev/null
+++ b/src/global/pubsub/index.ts
@@ -0,0 +1,2 @@
+export { PubSubModule } from '@/global/pubsub/pubsub.module';
+export { PUB_SUB } from '@/global/pubsub/pubsub.constants';
diff --git a/src/global/pubsub/pubsub.constants.ts b/src/global/pubsub/pubsub.constants.ts
new file mode 100644
index 00000000..4630172f
--- /dev/null
+++ b/src/global/pubsub/pubsub.constants.ts
@@ -0,0 +1,5 @@
+/**
+ * PubSub 주입 토큰. cross-cutting 포트(외부 부수효과 어댑터)라 토큰 주입을
+ * 사용한다 — 프로덕션은 RedisPubSub, spec은 in-memory PubSub로 대체된다.
+ */
+export const PUB_SUB = Symbol('PUB_SUB');
diff --git a/src/global/pubsub/pubsub.module.ts b/src/global/pubsub/pubsub.module.ts
new file mode 100644
index 00000000..d0b7e60e
--- /dev/null
+++ b/src/global/pubsub/pubsub.module.ts
@@ -0,0 +1,43 @@
+import { Global, Module, type OnModuleDestroy, Inject } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { RedisPubSub } from 'graphql-redis-subscriptions';
+import Redis, { type RedisOptions } from 'ioredis';
+
+import type { RedisConfig } from '@/config/redis.config';
+import { PUB_SUB } from '@/global/pubsub/pubsub.constants';
+
+/**
+ * GraphQL subscription용 Redis PubSub 전역 모듈.
+ * 수평 확장(다중 인스턴스) 시에도 이벤트가 모든 인스턴스에 전파되도록
+ * 처음부터 Redis 백엔드를 쓴다(사용자 확정). publisher/subscriber는
+ * Redis 프로토콜 제약(SUBSCRIBE 중 일반 명령 불가) 때문에 커넥션을 분리한다.
+ */
+@Global()
+@Module({
+  providers: [
+    {
+      provide: PUB_SUB,
+      inject: [ConfigService],
+      useFactory: (config: ConfigService): RedisPubSub => {
+        const redisConfig = config.getOrThrow<RedisConfig>('redis');
+        const options: RedisOptions = {
+          // Redis 미기동 시 부팅을 막지 않고 재시도만 한다(로컬 DX)
+          retryStrategy: (times: number) => Math.min(times * 500, 5000),
+          maxRetriesPerRequest: null,
+        };
+        return new RedisPubSub({
+          publisher: new Redis(redisConfig.url, options),
+          subscriber: new Redis(redisConfig.url, options),
+        });
+      },
+    },
+  ],
+  exports: [PUB_SUB],
+})
+export class PubSubModule implements OnModuleDestroy {
+  constructor(@Inject(PUB_SUB) private readonly pubSub: RedisPubSub) {}
+
+  async onModuleDestroy(): Promise<void> {
+    await this.pubSub.close();
+  }
+}
diff --git a/yarn.lock b/yarn.lock
index c6094299..abb88dd2 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3398,6 +3398,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@ioredis/commands@npm:1.10.0":
+  version: 1.10.0
+  resolution: "@ioredis/commands@npm:1.10.0"
+  checksum: 10c0/baf91e62d0e64ef2b5f7ca4413dc2456fe250e87483beac4a1c8ef1fe5ad0d2fcdeb9b89d4556d8ef6c7455c64a964359d729601fdb06b2f4c76c35dd59afa99
+  languageName: node
+  linkType: hard
+
 "@isaacs/balanced-match@npm:^4.0.1":
   version: 4.0.1
   resolution: "@isaacs/balanced-match@npm:4.0.1"
@@ -7394,7 +7401,11 @@ __metadata:
     express: "npm:^5.2.1"
     globals: "npm:^17.11.0"
     graphql: "npm:^16.14.0"
+    graphql-redis-subscriptions: "npm:^2.7.0"
+    graphql-subscriptions: "npm:^3.0.0"
+    graphql-ws: "npm:^6.2.1"
     husky: "npm:^9.1.7"
+    ioredis: "npm:^5.3.2"
     jest: "npm:^30"
     knip: "npm:^6.32.2"
     lint-staged: "npm:^17.3.0"
@@ -7722,6 +7733,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"cluster-key-slot@npm:1.1.1":
+  version: 1.1.1
+  resolution: "cluster-key-slot@npm:1.1.1"
+  checksum: 10c0/079b1ae86b20e2d53308a877b08de5e830722a45c07810569d0dab4955bed569da33ac9f79998289d014adf02cca7223a0647cb0ee6548a12ab3c4f9beac1377
+  languageName: node
+  linkType: hard
+
 "co@npm:^4.6.0":
   version: 4.6.0
   resolution: "co@npm:4.6.0"
@@ -8440,6 +8458,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"denque@npm:2.1.0":
+  version: 2.1.0
+  resolution: "denque@npm:2.1.0"
+  checksum: 10c0/f9ef81aa0af9c6c614a727cb3bd13c5d7db2af1abf9e6352045b86e85873e629690f6222f4edd49d10e4ccf8f078bbeec0794fafaf61b659c0589d0c511ec363
+  languageName: node
+  linkType: hard
+
 "depd@npm:2.0.0, depd@npm:^2.0.0, depd@npm:~2.0.0":
   version: 2.0.0
   resolution: "depd@npm:2.0.0"
@@ -10377,6 +10402,20 @@ __metadata:
   languageName: node
   linkType: hard
 
+"graphql-redis-subscriptions@npm:^2.7.0":
+  version: 2.7.0
+  resolution: "graphql-redis-subscriptions@npm:2.7.0"
+  dependencies:
+    ioredis: "npm:^5.3.2"
+  peerDependencies:
+    graphql-subscriptions: ^1.0.0 || ^2.0.0 || ^3.0.0
+  dependenciesMeta:
+    ioredis:
+      optional: true
+  checksum: 10c0/f98e9a16aa60d5470f6916f5a85b0b91898e3ec341a70ae3ddac878aa5b415dae9081ba872afdab5873cef3933fde1c3f1ee690ffa6d5b6d164a9165aed5cad1
+  languageName: node
+  linkType: hard
+
 "graphql-scalars@npm:^1.15.0":
   version: 1.25.0
   resolution: "graphql-scalars@npm:1.25.0"
@@ -10388,6 +10427,15 @@ __metadata:
   languageName: node
   linkType: hard
 
+"graphql-subscriptions@npm:^3.0.0":
+  version: 3.0.0
+  resolution: "graphql-subscriptions@npm:3.0.0"
+  peerDependencies:
+    graphql: ^15.7.2 || ^16.0.0
+  checksum: 10c0/10445c0d376773d15c887237ac460226b03e0b9c76789846f9133e3cfba6275b529f946634cd5a4e1f1f6c728b960714c8efc6c504af20ab05a3a1219ac9cc09
+  languageName: node
+  linkType: hard
+
 "graphql-tag@npm:2.12.6, graphql-tag@npm:^2.11.0":
   version: 2.12.6
   resolution: "graphql-tag@npm:2.12.6"
@@ -10399,7 +10447,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"graphql-ws@npm:6.2.1":
+"graphql-ws@npm:6.2.1, graphql-ws@npm:^6.2.1":
   version: 6.2.1
   resolution: "graphql-ws@npm:6.2.1"
   peerDependencies:
@@ -11096,6 +11144,21 @@ __metadata:
   languageName: node
   linkType: hard
 
+"ioredis@npm:^5.3.2":
+  version: 5.11.1
+  resolution: "ioredis@npm:5.11.1"
+  dependencies:
+    "@ioredis/commands": "npm:1.10.0"
+    cluster-key-slot: "npm:1.1.1"
+    debug: "npm:4.4.3"
+    denque: "npm:2.1.0"
+    redis-errors: "npm:1.2.0"
+    redis-parser: "npm:3.0.0"
+    standard-as-callback: "npm:2.1.0"
+  checksum: 10c0/a8b27043cf2c045dfc93f40a32ce24cf9f8b57799a37f4234c4b925c365ccf131629590f94a512f546fda2ba8ed034009c94c4933ecd44c50bc166636d929fd6
+  languageName: node
+  linkType: hard
+
 "ip-address@npm:^10.0.1":
   version: 10.1.0
   resolution: "ip-address@npm:10.1.0"
@@ -14619,6 +14682,22 @@ __metadata:
   languageName: node
   linkType: hard
 
+"redis-errors@npm:1.2.0, redis-errors@npm:^1.0.0":
+  version: 1.2.0
+  resolution: "redis-errors@npm:1.2.0"
+  checksum: 10c0/5b316736e9f532d91a35bff631335137a4f974927bb2fb42bf8c2f18879173a211787db8ac4c3fde8f75ed6233eb0888e55d52510b5620e30d69d7d719c8b8a7
+  languageName: node
+  linkType: hard
+
+"redis-parser@npm:3.0.0":
+  version: 3.0.0
+  resolution: "redis-parser@npm:3.0.0"
+  dependencies:
+    redis-errors: "npm:^1.0.0"
+  checksum: 10c0/ee16ac4c7b2a60b1f42a2cdaee22b005bd4453eb2d0588b8a4939718997ae269da717434da5d570fe0b05030466eeb3f902a58cf2e8e1ca058bf6c9c596f632f
+  languageName: node
+  linkType: hard
+
 "reflect-metadata@npm:^0.2.2":
   version: 0.2.2
   resolution: "reflect-metadata@npm:0.2.2"
@@ -15524,6 +15603,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"standard-as-callback@npm:2.1.0":
+  version: 2.1.0
+  resolution: "standard-as-callback@npm:2.1.0"
+  checksum: 10c0/012677236e3d3fdc5689d29e64ea8a599331c4babe86956bf92fc5e127d53f85411c5536ee0079c52c43beb0026b5ce7aa1d834dd35dd026e82a15d1bcaead1f
+  languageName: node
+  linkType: hard
+
 "statuses@npm:>= 1.5.0 < 2, statuses@npm:~1.5.0":
   version: 1.5.0
   resolution: "statuses@npm:1.5.0"

From 17884c9b324067c550ca499064ae73d7b2efc36c Mon Sep 17 00:00:00 2001
From: chanwoo7 <chanwoo9987@gmail.com>
Date: Wed, 2 Sep 2026 05:34:59 +0900
Subject: [PATCH 2/5] =?UTF-8?q?fix(conversation):=20Redis=20=EC=9E=A5?=
 =?UTF-8?q?=EC=95=A0=20=EA=B2=A9=EB=A6=AC=C2=B7=EC=9D=B4=EB=B2=A4=ED=8A=B8?=
 =?UTF-8?q?=20=EC=B5=9C=EC=8B=A0=20=EC=83=81=ED=83=9C=20=EB=B0=9C=ED=96=89?=
 =?UTF-8?q?=20(PR=20#270=20=EB=A6=AC=EB=B7=B0=20=EB=B0=98=EC=98=81)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Codex 지적 2건 반영.

- P1: maxRetriesPerRequest null이면 Redis 장애 시 커밋 완료된 mutation이
  발행 대기로 매달려 클라이언트 재시도 → 중복 전송 위험. 재시도를 2회로
  제한(enableOfflineQueue false)하고, 발행 실패는 events service에서
  경고 로그 후 삼킨다(구독자는 재조회 폴백) — 발행 실패 spec 추가
- P2: 동시 전송에서 잠금 해제 후 발행 순서가 커밋 순서와 어긋나면 늦은
  목록 이벤트가 과거 미리보기/시각으로 화면을 되돌릴 수 있다. 목록
  이벤트를 "발행 시점의 최신 커밋 상태"(대화 재조회 + 최신 메시지)로
  조립해 회귀를 차단 — 메시지 스트림 이벤트는 id를 실어 구독자 정렬
---
 src/features/conversation/index.ts            |  1 +
 .../conversation-events.service.spec.ts       | 32 +++++++++++++++++++
 .../services/conversation-events.service.ts   | 27 +++++++++++++---
 .../services/conversation-inquiry.service.ts  | 15 +++++++--
 .../services/seller-conversation.service.ts   | 28 +++++++++++-----
 src/global/pubsub/pubsub.module.ts            |  6 +++-
 6 files changed, 93 insertions(+), 16 deletions(-)

diff --git a/src/features/conversation/index.ts b/src/features/conversation/index.ts
index ad05881b..4db65102 100644
--- a/src/features/conversation/index.ts
+++ b/src/features/conversation/index.ts
@@ -4,3 +4,4 @@ export { ConversationRepository } from '@/features/conversation/repositories/con
 // subscription 이벤트 발행/구독 어댑터 — 판매자 답장(seller feature)도 같은 토픽을 쓴다.
 export { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
 export { toEventPreview } from '@/features/conversation/services/conversation-events-mappers.helper';
+export { toLastMessagePreview } from '@/features/conversation/services/conversation-center-mappers.helper';
diff --git a/src/features/conversation/services/conversation-events.service.spec.ts b/src/features/conversation/services/conversation-events.service.spec.ts
index 3a1709a0..f416e682 100644
--- a/src/features/conversation/services/conversation-events.service.spec.ts
+++ b/src/features/conversation/services/conversation-events.service.spec.ts
@@ -3,6 +3,7 @@
  * payload가 구독자에게 그대로 도착하는지까지 확인한다(DB 불필요).
  */
 import { RedisPubSub } from 'graphql-redis-subscriptions';
+import type { PubSubEngine } from 'graphql-subscriptions';
 import Redis from 'ioredis';
 import { GenericContainer, type StartedTestContainer } from 'testcontainers';
 
@@ -113,4 +114,35 @@ describe('ConversationEventsService (real Redis)', () => {
       lastMessagePreview: '픽업 문의',
     });
   });
+
+  it('발행 실패는 삼킨다 — 커밋된 전송을 Redis 장애가 실패로 만들지 않는다', async () => {
+    const failing = {
+      publish: jest.fn().mockRejectedValue(new Error('redis down')),
+    } as unknown as PubSubEngine;
+    const failingService = new ConversationEventsService(failing);
+
+    await expect(
+      failingService.publishBuyerListUpdate('1', {
+        conversationId: '1',
+        storeId: '2',
+        storeName: '매장',
+        lastMessagePreview: null,
+        lastMessageAt: '2026-08-01T12:00:00.000Z',
+        unreadCount: 0,
+      }),
+    ).resolves.toBeUndefined();
+    await expect(
+      failingService.publishMessagesAdded([
+        {
+          id: '1',
+          conversationId: '1',
+          senderType: 'USER',
+          bodyFormat: 'TEXT',
+          bodyText: '문의',
+          bodyHtml: null,
+          createdAt: new Date(),
+        },
+      ]),
+    ).resolves.toBeUndefined();
+  });
 });
diff --git a/src/features/conversation/services/conversation-events.service.ts b/src/features/conversation/services/conversation-events.service.ts
index 0b401721..5b760acd 100644
--- a/src/features/conversation/services/conversation-events.service.ts
+++ b/src/features/conversation/services/conversation-events.service.ts
@@ -1,4 +1,4 @@
-import { Inject, Injectable } from '@nestjs/common';
+import { Inject, Injectable, Logger } from '@nestjs/common';
 import type { PubSubEngine } from 'graphql-subscriptions';
 
 import { toConversationMessageEvent } from '@/features/conversation/services/conversation-events-mappers.helper';
@@ -16,8 +16,27 @@ import { PUB_SUB } from '@/global/pubsub';
  */
 @Injectable()
 export class ConversationEventsService {
+  private readonly logger = new Logger(ConversationEventsService.name);
+
   constructor(@Inject(PUB_SUB) private readonly pubSub: PubSubEngine) {}
 
+  /**
+   * 발행은 DB 커밋 이후의 부수효과 — Redis 장애가 이미 성공한 전송을
+   * 실패로 둔갑시키면 클라이언트 재시도로 중복 전송이 난다(리뷰 반영).
+   * 실패는 경고 로그만 남기고 삼킨다(구독자는 재조회 폴백).
+   */
+  private async safePublish(topic: string, payload: unknown): Promise<void> {
+    try {
+      await this.pubSub.publish(topic, payload);
+    } catch (e) {
+      this.logger.warn(
+        `subscription publish 실패 (topic=${topic}): ${
+          e instanceof Error ? e.message : String(e)
+        }`,
+      );
+    }
+  }
+
   private messageTopic(conversationId: string): string {
     return `conversation.message.${conversationId}`;
   }
@@ -35,7 +54,7 @@ export class ConversationEventsService {
     messages: ConversationMessageOutput[],
   ): Promise<void> {
     for (const message of messages) {
-      await this.pubSub.publish(
+      await this.safePublish(
         this.messageTopic(message.conversationId),
         toConversationMessageEvent(message),
       );
@@ -46,14 +65,14 @@ export class ConversationEventsService {
     accountId: string,
     event: ConversationListUpdateEvent,
   ): Promise<void> {
-    await this.pubSub.publish(this.buyerTopic(accountId), event);
+    await this.safePublish(this.buyerTopic(accountId), event);
   }
 
   async publishSellerListUpdate(
     storeId: string,
     event: SellerConversationListUpdateEvent,
   ): Promise<void> {
-    await this.pubSub.publish(this.sellerTopic(storeId), event);
+    await this.safePublish(this.sellerTopic(storeId), event);
   }
 
   messageAddedIterator(conversationId: string): AsyncIterator<unknown> {
diff --git a/src/features/conversation/services/conversation-inquiry.service.ts b/src/features/conversation/services/conversation-inquiry.service.ts
index 1f735fc2..4095581c 100644
--- a/src/features/conversation/services/conversation-inquiry.service.ts
+++ b/src/features/conversation/services/conversation-inquiry.service.ts
@@ -12,6 +12,7 @@ import {
   type ConversationMessageEntry,
 } from '@/features/conversation/repositories/conversation.repository';
 import { ConversationBaseService } from '@/features/conversation/services/conversation-base.service';
+import { toLastMessagePreview } from '@/features/conversation/services/conversation-center-mappers.helper';
 import { toEventPreview } from '@/features/conversation/services/conversation-events-mappers.helper';
 import { ConversationEventsService } from '@/features/conversation/services/conversation-events.service';
 import {
@@ -185,9 +186,11 @@ export class ConversationInquiryService extends ConversationBaseService {
   }): Promise<void> {
     const lastMessage = args.messages[args.messages.length - 1];
     if (!lastMessage) return;
-    // 시각은 repository가 잠금 아래 채번한 저장 시각을 그대로 쓴다
-    const lastMessageAtIso = lastMessage.createdAt.toISOString();
 
+    // 목록 이벤트는 "발행 시점의 최신 커밋 상태"를 다시 읽어 조립한다 —
+    // 동시 전송에서 잠금 해제 후 발행 순서가 커밋 순서와 어긋나도, 늦게
+    // 발행된 이벤트가 과거 미리보기/시각으로 화면을 되돌리지 않는다
+    // (리뷰 반영). 메시지 스트림 이벤트는 id를 실어 구독자가 정렬한다.
     const conversation = await this.repo.findConversationByAccountAndStore({
       accountId: args.accountId,
       storeId: args.storeId,
@@ -198,7 +201,13 @@ export class ConversationInquiryService extends ConversationBaseService {
         ])
       : [undefined];
 
-    const preview = toEventPreview(lastMessage);
+    const preview = extras
+      ? toLastMessagePreview(extras.lastMessage)
+      : toEventPreview(lastMessage);
+    const lastMessageAtIso = (
+      conversation?.last_message_at ?? lastMessage.createdAt
+    ).toISOString();
+
     await this.events.publishMessagesAdded(args.messages);
     await this.events.publishBuyerListUpdate(args.accountId.toString(), {
       conversationId: args.conversationId.toString(),
diff --git a/src/features/seller/services/seller-conversation.service.ts b/src/features/seller/services/seller-conversation.service.ts
index 892cbb34..5328c3e4 100644
--- a/src/features/seller/services/seller-conversation.service.ts
+++ b/src/features/seller/services/seller-conversation.service.ts
@@ -20,6 +20,7 @@ import {
   ConversationEventsService,
   ConversationRepository,
   toEventPreview,
+  toLastMessagePreview,
 } from '@/features/conversation';
 import {
   BODY_HTML_REQUIRED,
@@ -193,18 +194,29 @@ export class SellerConversationService extends SellerBaseService {
       bodyHtml: args.message.bodyHtml,
       createdAt: args.message.createdAt,
     };
-    const preview = toEventPreview(message);
-    const lastMessageAtIso = args.message.createdAt.toISOString();
-
-    const [store, [extras]] = await Promise.all([
+    // 목록 이벤트는 "발행 시점의 최신 커밋 상태"를 다시 읽어 조립한다 —
+    // 동시 전송에서 발행 순서가 커밋 순서와 어긋나도 늦은 이벤트가 과거
+    // 상태로 화면을 되돌리지 않는다(리뷰 반영). 메시지 스트림은 id 정렬.
+    const [store, fresh] = await Promise.all([
       this.conversationRepository.findStoreNameById(args.storeId),
-      this.conversationRepository.getConversationListExtras([
+      this.conversationRepository.findConversationByIdAndStore({
+        conversationId: args.conversation.id,
+        storeId: args.storeId,
+      }),
+    ]);
+    const [extras] =
+      await this.conversationRepository.getConversationListExtras([
         {
           id: args.conversation.id,
-          last_read_at: args.conversation.last_read_at,
+          last_read_at: fresh?.last_read_at ?? args.conversation.last_read_at,
         },
-      ]),
-    ]);
+      ]);
+    const preview = extras
+      ? toLastMessagePreview(extras.lastMessage)
+      : toEventPreview(message);
+    const lastMessageAtIso = (
+      fresh?.last_message_at ?? args.message.createdAt
+    ).toISOString();
 
     await this.conversationEvents.publishMessagesAdded([message]);
     await this.conversationEvents.publishBuyerListUpdate(
diff --git a/src/global/pubsub/pubsub.module.ts b/src/global/pubsub/pubsub.module.ts
index d0b7e60e..bf27a4ef 100644
--- a/src/global/pubsub/pubsub.module.ts
+++ b/src/global/pubsub/pubsub.module.ts
@@ -23,7 +23,11 @@ import { PUB_SUB } from '@/global/pubsub/pubsub.constants';
         const options: RedisOptions = {
           // Redis 미기동 시 부팅을 막지 않고 재시도만 한다(로컬 DX)
           retryStrategy: (times: number) => Math.min(times * 500, 5000),
-          maxRetriesPerRequest: null,
+          // 발행은 DB 커밋 이후의 부수효과 — 무한 재시도(null)로 두면 Redis
+          // 장애 시 mutation 응답이 매달린다(리뷰 반영). 짧게 실패시키고
+          // 실패 처리는 발행부(try/catch)가 담당한다.
+          maxRetriesPerRequest: 2,
+          enableOfflineQueue: false,
         };
         return new RedisPubSub({
           publisher: new Redis(redisConfig.url, options),

From b3d3e42e87717fa94a47b759aa7a76ac7e2a9b54 Mon Sep 17 00:00:00 2001
From: chanwoo7 <chanwoo9987@gmail.com>
Date: Wed, 2 Sep 2026 05:43:08 +0900
Subject: [PATCH 3/5] =?UTF-8?q?fix(conversation):=20=EB=AA=A9=EB=A1=9D=20?=
 =?UTF-8?q?=EC=9D=B4=EB=B2=A4=ED=8A=B8=20=EC=8A=A4=EB=83=85=EC=83=B7?=
 =?UTF-8?q?=EC=9D=84=20=EB=8B=A8=EC=9D=BC=20=ED=8A=B8=EB=9E=9C=EC=9E=AD?=
 =?UTF-8?q?=EC=85=98=EC=9C=BC=EB=A1=9C=20(PR=20#270=20=EB=A6=AC=EB=B7=B0?=
 =?UTF-8?q?=20=EB=B0=98=EC=98=81)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Codex 지적 반영: 발행 시점 재조회가 대화 row·최신 메시지·안읽음 수의
독립 조회로 쪼개져 있어, 경쟁 커밋이 사이에 끼면 "남의 미리보기 + 내
시각" 혼합 상태가 이벤트로 나갈 수 있었다. 대화·매장명·최신 메시지·
안읽음 수를 한 트랜잭션(단일 REPEATABLE READ 스냅샷)에서 읽는
getConversationEventSnapshot으로 통합 — 구매자·판매자 발행 경로 공용.
findStoreNameById는 스냅샷에 흡수돼 제거.
---
 .../repositories/conversation.repository.ts   | 44 ++++++++++++++++---
 .../services/conversation-inquiry.service.ts  | 31 ++++++-------
 .../services/seller-conversation.service.ts   | 35 ++++++---------
 3 files changed, 65 insertions(+), 45 deletions(-)

diff --git a/src/features/conversation/repositories/conversation.repository.ts b/src/features/conversation/repositories/conversation.repository.ts
index f4e5f650..93c58a45 100644
--- a/src/features/conversation/repositories/conversation.repository.ts
+++ b/src/features/conversation/repositories/conversation.repository.ts
@@ -295,11 +295,45 @@ export class ConversationRepository {
     });
   }
 
-  /** 이벤트 payload용 매장명 단건 조회. */
-  async findStoreNameById(storeId: bigint) {
-    return this.prisma.store.findFirst({
-      where: { id: storeId, deleted_at: undefined },
-      select: { store_name: true },
+  /**
+   * 목록 갱신 이벤트용 대화 스냅샷 — 한 트랜잭션(단일 REPEATABLE READ
+   * 스냅샷)에서 대화·매장명·최신 메시지·안읽음 수를 함께 읽는다. 독립
+   * 조회로 쪼개면 경쟁 커밋이 끼어들어 "B의 미리보기 + A의 시각" 같은
+   * 혼합 상태가 이벤트로 나갈 수 있다(리뷰 반영).
+   */
+  async getConversationEventSnapshot(conversationId: bigint) {
+    return this.prisma.$transaction(async (tx) => {
+      const conversation = await tx.storeConversation.findFirst({
+        where: { id: conversationId, deleted_at: undefined },
+        select: {
+          id: true,
+          account_id: true,
+          store_id: true,
+          last_message_at: true,
+          last_read_at: true,
+          store: { select: { store_name: true } },
+        },
+      });
+      if (!conversation) return null;
+
+      const [lastMessage, unreadCount] = await Promise.all([
+        tx.storeConversationMessage.findFirst({
+          where: { conversation_id: conversationId },
+          orderBy: { id: 'desc' },
+          select: { body_format: true, body_text: true, body_html: true },
+        }),
+        tx.storeConversationMessage.count({
+          where: {
+            conversation_id: conversationId,
+            sender_type: { not: ConversationSenderType.USER },
+            ...(conversation.last_read_at
+              ? { created_at: { gt: conversation.last_read_at } }
+              : {}),
+          },
+        }),
+      ]);
+
+      return { conversation, lastMessage, unreadCount };
     });
   }
 
diff --git a/src/features/conversation/services/conversation-inquiry.service.ts b/src/features/conversation/services/conversation-inquiry.service.ts
index 4095581c..eb4e5822 100644
--- a/src/features/conversation/services/conversation-inquiry.service.ts
+++ b/src/features/conversation/services/conversation-inquiry.service.ts
@@ -187,26 +187,21 @@ export class ConversationInquiryService extends ConversationBaseService {
     const lastMessage = args.messages[args.messages.length - 1];
     if (!lastMessage) return;
 
-    // 목록 이벤트는 "발행 시점의 최신 커밋 상태"를 다시 읽어 조립한다 —
-    // 동시 전송에서 잠금 해제 후 발행 순서가 커밋 순서와 어긋나도, 늦게
-    // 발행된 이벤트가 과거 미리보기/시각으로 화면을 되돌리지 않는다
-    // (리뷰 반영). 메시지 스트림 이벤트는 id를 실어 구독자가 정렬한다.
-    const conversation = await this.repo.findConversationByAccountAndStore({
-      accountId: args.accountId,
-      storeId: args.storeId,
-    });
-    const [extras] = conversation
-      ? await this.repo.getConversationListExtras([
-          { id: conversation.id, last_read_at: conversation.last_read_at },
-        ])
-      : [undefined];
-
-    const preview = extras
-      ? toLastMessagePreview(extras.lastMessage)
+    // 목록 이벤트는 "발행 시점의 최신 커밋 상태"를 단일 트랜잭션 스냅샷
+    // 으로 다시 읽어 조립한다 — 독립 조회로 쪼개면 경쟁 커밋이 끼어들어
+    // 혼합 상태(남의 미리보기 + 내 시각)가 나갈 수 있다(리뷰 반영).
+    // 메시지 스트림 이벤트는 id를 실어 구독자가 정렬한다.
+    const snapshot = await this.repo.getConversationEventSnapshot(
+      args.conversationId,
+    );
+
+    const preview = snapshot
+      ? toLastMessagePreview(snapshot.lastMessage)
       : toEventPreview(lastMessage);
     const lastMessageAtIso = (
-      conversation?.last_message_at ?? lastMessage.createdAt
+      snapshot?.conversation.last_message_at ?? lastMessage.createdAt
     ).toISOString();
+    const unreadCount = snapshot?.unreadCount ?? 0;
 
     await this.events.publishMessagesAdded(args.messages);
     await this.events.publishBuyerListUpdate(args.accountId.toString(), {
@@ -215,7 +210,7 @@ export class ConversationInquiryService extends ConversationBaseService {
       storeName: args.storeName,
       lastMessagePreview: preview,
       lastMessageAt: lastMessageAtIso,
-      unreadCount: extras?.unreadCount ?? 0,
+      unreadCount,
     });
     await this.events.publishSellerListUpdate(args.storeId.toString(), {
       conversationId: args.conversationId.toString(),
diff --git a/src/features/seller/services/seller-conversation.service.ts b/src/features/seller/services/seller-conversation.service.ts
index 5328c3e4..5e0c7137 100644
--- a/src/features/seller/services/seller-conversation.service.ts
+++ b/src/features/seller/services/seller-conversation.service.ts
@@ -194,29 +194,20 @@ export class SellerConversationService extends SellerBaseService {
       bodyHtml: args.message.bodyHtml,
       createdAt: args.message.createdAt,
     };
-    // 목록 이벤트는 "발행 시점의 최신 커밋 상태"를 다시 읽어 조립한다 —
-    // 동시 전송에서 발행 순서가 커밋 순서와 어긋나도 늦은 이벤트가 과거
-    // 상태로 화면을 되돌리지 않는다(리뷰 반영). 메시지 스트림은 id 정렬.
-    const [store, fresh] = await Promise.all([
-      this.conversationRepository.findStoreNameById(args.storeId),
-      this.conversationRepository.findConversationByIdAndStore({
-        conversationId: args.conversation.id,
-        storeId: args.storeId,
-      }),
-    ]);
-    const [extras] =
-      await this.conversationRepository.getConversationListExtras([
-        {
-          id: args.conversation.id,
-          last_read_at: fresh?.last_read_at ?? args.conversation.last_read_at,
-        },
-      ]);
-    const preview = extras
-      ? toLastMessagePreview(extras.lastMessage)
+    // 목록 이벤트는 발행 시점의 최신 커밋 상태를 단일 트랜잭션 스냅샷으로
+    // 조립한다 — 독립 조회로 쪼개면 경쟁 커밋이 끼어들어 혼합 상태가 나갈
+    // 수 있다(리뷰 반영). 메시지 스트림은 id 정렬.
+    const snapshot =
+      await this.conversationRepository.getConversationEventSnapshot(
+        args.conversation.id,
+      );
+    const preview = snapshot
+      ? toLastMessagePreview(snapshot.lastMessage)
       : toEventPreview(message);
     const lastMessageAtIso = (
-      fresh?.last_message_at ?? args.message.createdAt
+      snapshot?.conversation.last_message_at ?? args.message.createdAt
     ).toISOString();
+    const storeName = snapshot?.conversation.store.store_name ?? '';
 
     await this.conversationEvents.publishMessagesAdded([message]);
     await this.conversationEvents.publishBuyerListUpdate(
@@ -224,10 +215,10 @@ export class SellerConversationService extends SellerBaseService {
       {
         conversationId: args.conversation.id.toString(),
         storeId: args.storeId.toString(),
-        storeName: store?.store_name ?? '',
+        storeName,
         lastMessagePreview: preview,
         lastMessageAt: lastMessageAtIso,
-        unreadCount: extras?.unreadCount ?? 0,
+        unreadCount: snapshot?.unreadCount ?? 0,
       },
     );
     await this.conversationEvents.publishSellerListUpdate(

From f2c5e13f5db4b2a8aecaf95bac0cf275b026395c Mon Sep 17 00:00:00 2001
From: chanwoo7 <chanwoo9987@gmail.com>
Date: Wed, 2 Sep 2026 05:51:13 +0900
Subject: [PATCH 4/5] =?UTF-8?q?fix(conversation):=20=EC=BB=A4=EB=B0=8B=20?=
 =?UTF-8?q?=ED=9B=84=20=EB=B0=9C=ED=96=89=20=EC=A0=84=EC=B2=B4=20=EA=B2=A9?=
 =?UTF-8?q?=EB=A6=AC=20+=20=EC=9D=B4=EB=B2=A4=ED=8A=B8=20=EC=88=9C?=
 =?UTF-8?q?=EC=84=9C=20=EA=B3=84=EC=95=BD=20=EB=AA=85=EC=8B=9C=20(PR=20#27?=
 =?UTF-8?q?0=20=EB=A6=AC=EB=B7=B0=20=EB=B0=98=EC=98=81)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Codex 지적 2건 대응.

- P1(반영): 스냅샷 조회를 포함한 커밋 후 발행 경로 전체를 try/catch로
  격리(구매자·판매자) — DB 순단이 이미 저장된 전송을 실패로 둔갑시켜
  재시도 중복을 만들지 않도록. 실패는 경고 로그만
- P2(부분 반영): 완전한 커밋 순서 발행은 outbox 패턴이 필요해 범위와
  비례하지 않음. 이벤트에 이미 실린 lastMessageAt(목록)·id(메시지)로
  구독자가 stale 이벤트를 폐기하는 계약을 SDL에 명시
---
 .../conversation-subscription.graphql         |  8 ++++--
 .../services/conversation-inquiry.service.ts  | 25 ++++++++++++++++++-
 .../services/seller-conversation.service.ts   | 25 +++++++++++++++++++
 3 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/src/features/conversation/conversation-subscription.graphql b/src/features/conversation/conversation-subscription.graphql
index 43806d39..3b671b4b 100644
--- a/src/features/conversation/conversation-subscription.graphql
+++ b/src/features/conversation/conversation-subscription.graphql
@@ -10,7 +10,11 @@ extend type Subscription {
   sellerConversationUpdated: SellerConversationListUpdate!
 }
 
-"""구매자 대화 목록 갱신 이벤트"""
+"""
+구매자 대화 목록 갱신 이벤트.
+이벤트 간 도착 순서는 보장되지 않는다 — 구독자는 lastMessageAt을 비교해
+이미 표시 중인 상태보다 오래된 이벤트를 폐기해야 한다(메시지 스트림은 id 기준).
+"""
 type ConversationListUpdate {
   conversationId: ID!
   storeId: ID!
@@ -22,7 +26,7 @@ type ConversationListUpdate {
   unreadCount: Int!
 }
 
-"""판매자 대화 목록 갱신 이벤트"""
+"""판매자 대화 목록 갱신 이벤트. 도착 순서 비보장 — lastMessageAt 기준 폐기 규칙 동일."""
 type SellerConversationListUpdate {
   conversationId: ID!
   accountId: ID!
diff --git a/src/features/conversation/services/conversation-inquiry.service.ts b/src/features/conversation/services/conversation-inquiry.service.ts
index eb4e5822..7c78ec84 100644
--- a/src/features/conversation/services/conversation-inquiry.service.ts
+++ b/src/features/conversation/services/conversation-inquiry.service.ts
@@ -1,4 +1,4 @@
-import { Injectable, NotFoundException } from '@nestjs/common';
+import { Injectable, Logger, NotFoundException } from '@nestjs/common';
 import { ConversationBodyFormat, ConversationSenderType } from '@prisma/client';
 
 import { parseId } from '@/common/utils/id-parser';
@@ -27,6 +27,8 @@ import type {
 
 @Injectable()
 export class ConversationInquiryService extends ConversationBaseService {
+  private readonly logger = new Logger(ConversationInquiryService.name);
+
   constructor(
     repo: ConversationRepository,
     private readonly events: ConversationEventsService,
@@ -183,6 +185,27 @@ export class ConversationInquiryService extends ConversationBaseService {
     storeName: string;
     conversationId: bigint;
     messages: ConversationMessagesPayload['messages'];
+  }): Promise<void> {
+    // 커밋 이후의 부수효과 전체(스냅샷 조회 포함)를 격리한다 — 여기서 나는
+    // 예외가 mutation을 실패로 둔갑시키면 클라이언트 재시도로 중복 전송이
+    // 난다(리뷰 반영). 실패는 경고 로그만 남긴다.
+    try {
+      await this.doPublishBuyerSendEvents(args);
+    } catch (e) {
+      this.logger.warn(
+        `대화 이벤트 발행 실패 (conversationId=${args.conversationId}): ${
+          e instanceof Error ? e.message : String(e)
+        }`,
+      );
+    }
+  }
+
+  private async doPublishBuyerSendEvents(args: {
+    accountId: bigint;
+    storeId: bigint;
+    storeName: string;
+    conversationId: bigint;
+    messages: ConversationMessagesPayload['messages'];
   }): Promise<void> {
     const lastMessage = args.messages[args.messages.length - 1];
     if (!lastMessage) return;
diff --git a/src/features/seller/services/seller-conversation.service.ts b/src/features/seller/services/seller-conversation.service.ts
index 5e0c7137..aceacb3d 100644
--- a/src/features/seller/services/seller-conversation.service.ts
+++ b/src/features/seller/services/seller-conversation.service.ts
@@ -2,6 +2,7 @@ import {
   BadRequestException,
   Inject,
   Injectable,
+  Logger,
   NotFoundException,
 } from '@nestjs/common';
 import {
@@ -48,6 +49,8 @@ import type {
 
 @Injectable()
 export class SellerConversationService extends SellerBaseService {
+  private readonly logger = new Logger(SellerConversationService.name);
+
   constructor(
     repo: SellerRepository,
     @Inject(AUDIT_LOG_REPOSITORY)
@@ -184,6 +187,28 @@ export class SellerConversationService extends SellerBaseService {
     };
     storeId: bigint;
     message: SellerConversationMessageOutput;
+  }): Promise<void> {
+    // 커밋 이후의 부수효과 전체(스냅샷 조회 포함)를 격리한다 — 예외가
+    // 이미 저장된 답장을 실패로 둔갑시키면 재시도 중복이 난다(리뷰 반영).
+    try {
+      await this.doPublishSellerReplyEvents(args);
+    } catch (e) {
+      this.logger.warn(
+        `대화 이벤트 발행 실패 (conversationId=${args.conversation.id}): ${
+          e instanceof Error ? e.message : String(e)
+        }`,
+      );
+    }
+  }
+
+  private async doPublishSellerReplyEvents(args: {
+    conversation: {
+      id: bigint;
+      account_id: bigint;
+      last_read_at: Date | null;
+    };
+    storeId: bigint;
+    message: SellerConversationMessageOutput;
   }): Promise<void> {
     const message = {
       id: args.message.id,

From e028c612390905e4b9184d81526e4d5523383414 Mon Sep 17 00:00:00 2001
From: chanwoo7 <chanwoo9987@gmail.com>
Date: Wed, 2 Sep 2026 06:01:52 +0900
Subject: [PATCH 5/5] =?UTF-8?q?fix(conversation):=20=EB=AA=A9=EB=A1=9D=20?=
 =?UTF-8?q?=EC=9D=B4=EB=B2=A4=ED=8A=B8=EC=97=90=20lastReadAt=20=EC=8B=A4?=
 =?UTF-8?q?=EC=96=B4=20=ED=8F=90=EA=B8=B0=20=EA=B7=9C=EC=B9=99=20=ED=99=95?=
 =?UTF-8?q?=EC=9E=A5=20+=20=EC=8A=A4=EB=83=85=EC=83=B7=20=EB=A7=A4?=
 =?UTF-8?q?=EC=9E=A5=EB=AA=85=20(PR=20#270=20=EB=A6=AC=EB=B7=B0=20?=
 =?UTF-8?q?=EB=B0=98=EC=98=81)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Codex 지적 2건 반영.

- P2: 읽음 처리는 last_message_at을 바꾸지 않아, 읽음 이후 도착한 지연
  이벤트의 stale unreadCount를 lastMessageAt 비교로 걸러낼 수 없었다.
  이벤트에 스냅샷 시점 lastReadAt을 추가하고 구독자 폐기 규칙을
  (lastMessageAt, lastReadAt) 사전식 비교로 확장(SDL 계약 갱신) —
  읽음은 lastReadAt을 전진시키므로 stale 배지 부활이 걸러진다
- P2: 구매자 이벤트 매장명도 스냅샷 값 우선 — 최초 조회 후 개명 시
  최신 상태에 옛 이름이 섞여 나가던 문제
---
 .../conversation/conversation-subscription.graphql        | 8 ++++++--
 .../services/conversation-events.service.spec.ts          | 2 ++
 .../conversation/services/conversation-inquiry.service.ts | 8 +++++++-
 .../conversation/types/conversation-output.type.ts        | 1 +
 .../seller/services/seller-conversation.service.ts        | 3 +++
 5 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/src/features/conversation/conversation-subscription.graphql b/src/features/conversation/conversation-subscription.graphql
index 3b671b4b..ebd22cd3 100644
--- a/src/features/conversation/conversation-subscription.graphql
+++ b/src/features/conversation/conversation-subscription.graphql
@@ -12,8 +12,10 @@ extend type Subscription {
 
 """
 구매자 대화 목록 갱신 이벤트.
-이벤트 간 도착 순서는 보장되지 않는다 — 구독자는 lastMessageAt을 비교해
-이미 표시 중인 상태보다 오래된 이벤트를 폐기해야 한다(메시지 스트림은 id 기준).
+이벤트 간 도착 순서는 보장되지 않는다 — 구독자는 (lastMessageAt, lastReadAt)을
+사전식으로 비교해 이미 표시 중인 상태보다 오래된 이벤트를 폐기해야 한다.
+읽음 처리는 lastReadAt만 전진시키므로, 읽음 이후 도착한 지연 이벤트도 이 비교로
+걸러진다(메시지 스트림은 id 기준).
 """
 type ConversationListUpdate {
   conversationId: ID!
@@ -22,6 +24,8 @@ type ConversationListUpdate {
   """마지막 메시지 미리보기(HTML은 태그 제거)"""
   lastMessagePreview: String
   lastMessageAt: DateTime!
+  """이벤트 스냅샷 시점의 구매자 마지막 읽음 시각(폐기 규칙 비교용)"""
+  lastReadAt: DateTime
   """이벤트 시점의 안읽은 수신 메시지 수"""
   unreadCount: Int!
 }
diff --git a/src/features/conversation/services/conversation-events.service.spec.ts b/src/features/conversation/services/conversation-events.service.spec.ts
index f416e682..9a6cec35 100644
--- a/src/features/conversation/services/conversation-events.service.spec.ts
+++ b/src/features/conversation/services/conversation-events.service.spec.ts
@@ -96,6 +96,7 @@ describe('ConversationEventsService (real Redis)', () => {
       storeName: '해즈 케이크',
       lastMessagePreview: '답변 드리겠습니다',
       lastMessageAt: '2026-08-01T12:00:00.000Z',
+      lastReadAt: null,
       unreadCount: 2,
     });
     await service.publishSellerListUpdate('3', {
@@ -128,6 +129,7 @@ describe('ConversationEventsService (real Redis)', () => {
         storeName: '매장',
         lastMessagePreview: null,
         lastMessageAt: '2026-08-01T12:00:00.000Z',
+        lastReadAt: null,
         unreadCount: 0,
       }),
     ).resolves.toBeUndefined();
diff --git a/src/features/conversation/services/conversation-inquiry.service.ts b/src/features/conversation/services/conversation-inquiry.service.ts
index 7c78ec84..b6ebbded 100644
--- a/src/features/conversation/services/conversation-inquiry.service.ts
+++ b/src/features/conversation/services/conversation-inquiry.service.ts
@@ -224,15 +224,21 @@ export class ConversationInquiryService extends ConversationBaseService {
     const lastMessageAtIso = (
       snapshot?.conversation.last_message_at ?? lastMessage.createdAt
     ).toISOString();
+    const lastReadAtIso =
+      snapshot?.conversation.last_read_at?.toISOString() ?? null;
     const unreadCount = snapshot?.unreadCount ?? 0;
+    // 매장명도 스냅샷 값을 우선한다 — 최초 조회 후 개명되면 최신 메시지
+    // 상태에 옛 이름이 실려 나갈 수 있다(리뷰 반영)
+    const storeName = snapshot?.conversation.store.store_name ?? args.storeName;
 
     await this.events.publishMessagesAdded(args.messages);
     await this.events.publishBuyerListUpdate(args.accountId.toString(), {
       conversationId: args.conversationId.toString(),
       storeId: args.storeId.toString(),
-      storeName: args.storeName,
+      storeName,
       lastMessagePreview: preview,
       lastMessageAt: lastMessageAtIso,
+      lastReadAt: lastReadAtIso,
       unreadCount,
     });
     await this.events.publishSellerListUpdate(args.storeId.toString(), {
diff --git a/src/features/conversation/types/conversation-output.type.ts b/src/features/conversation/types/conversation-output.type.ts
index 8581eb54..b1965fed 100644
--- a/src/features/conversation/types/conversation-output.type.ts
+++ b/src/features/conversation/types/conversation-output.type.ts
@@ -84,6 +84,7 @@ export interface ConversationListUpdateEvent {
   storeName: string;
   lastMessagePreview: string | null;
   lastMessageAt: string;
+  lastReadAt: string | null;
   unreadCount: number;
 }
 
diff --git a/src/features/seller/services/seller-conversation.service.ts b/src/features/seller/services/seller-conversation.service.ts
index aceacb3d..4d46a9ed 100644
--- a/src/features/seller/services/seller-conversation.service.ts
+++ b/src/features/seller/services/seller-conversation.service.ts
@@ -233,6 +233,8 @@ export class SellerConversationService extends SellerBaseService {
       snapshot?.conversation.last_message_at ?? args.message.createdAt
     ).toISOString();
     const storeName = snapshot?.conversation.store.store_name ?? '';
+    const lastReadAtIso =
+      snapshot?.conversation.last_read_at?.toISOString() ?? null;
 
     await this.conversationEvents.publishMessagesAdded([message]);
     await this.conversationEvents.publishBuyerListUpdate(
@@ -243,6 +245,7 @@ export class SellerConversationService extends SellerBaseService {
         storeName,
         lastMessagePreview: preview,
         lastMessageAt: lastMessageAtIso,
+        lastReadAt: lastReadAtIso,
         unreadCount: snapshot?.unreadCount ?? 0,
       },
     );