feat(client): 新增会话管理与消息落库能力

补齐客户端会话生命周期接口（创建、列表、消息分页、改名、删除），并在流式 chat 中强制绑定 sessionId 与落库消息，确保会话标题和历史可追踪，同时统一 Swagger 文档为 DTO 驱动以减少重复维护。 Made-with: Cursor
2026-04-22 23:32:10 +08:00
parent bc13417efd
commit 32303d099a
16 changed files with 833 additions and 146 deletions
--- a/src/apps/client-app/auth/client-auth.controller.ts
+++ b/src/apps/client-app/auth/client-auth.controller.ts
@@ -1,6 +1,11 @@
 import { Body, Controller, Inject, Post } from '@nestjs/common';
 import { ApiBody, ApiOkResponse, ApiOperation, ApiTags } from '@nestjs/swagger';
 import { ClientAuthService } from './client-auth.service';
+import {
+  ClientLoginResponseDto,
+  ClientRefreshResponseDto,
+  ClientSendSmsResponseDto,
+} from './dto/client-auth-response.dto';
 import {
  ClientLoginDto,
  ClientRefreshDto,
@@ -17,90 +22,24 @@ export class ClientAuthController {

  @Post('sms/send')
  @ApiOperation({ summary: '发送短信验证码（MVP 为 mock）' })
-  @ApiBody({
-    schema: {
-      type: 'object',
-      description: '发送短信验证码请求体',
-      properties: {
-        phone: { type: 'string', description: '手机号', example: '13800000000' },
-        scene: { type: 'string', description: '业务场景', example: 'login' },
-      },
-      required: ['phone', 'scene'],
-    },
-  })
-  @ApiOkResponse({
-    description: '发送成功（MVP mock）',
-    schema: {
-      type: 'object',
-      properties: {
-        requestId: { type: 'string', example: 'sms_1710000000000' },
-        phone: { type: 'string', example: '13800000000' },
-        scene: { type: 'string', example: 'login' },
-        expireIn: { type: 'number', example: 300 },
-        testCode: { type: 'string', example: '123456' },
-      },
-    },
-  })
+  @ApiBody({ type: ClientSendSmsDto })
+  @ApiOkResponse({ description: '发送成功（MVP mock）', type: ClientSendSmsResponseDto })
  async sendSms(@Body() body: ClientSendSmsDto) {
    return this.clientAuthService.sendSmsCode(body.phone, body.scene);
  }

  @Post('sms/login')
  @ApiOperation({ summary: '短信验证码登录（MVP 固定验证码 123456）' })
-  @ApiBody({
-    schema: {
-      type: 'object',
-      description: '短信验证码登录请求体',
-      properties: {
-        phone: { type: 'string', description: '手机号', example: '13800000000' },
-        code: { type: 'string', description: '短信验证码', example: '123456' },
-      },
-      required: ['phone', 'code'],
-    },
-  })
-  @ApiOkResponse({
-    description: '登录成功返回 token',
-    schema: {
-      type: 'object',
-      properties: {
-        accessToken: { type: 'string' },
-        refreshToken: { type: 'string' },
-        user: {
-          type: 'object',
-          properties: {
-            id: { type: 'string', example: 'u_13800000000' },
-            phone: { type: 'string', example: '13800000000' },
-          },
-        },
-      },
-    },
-  })
+  @ApiBody({ type: ClientLoginDto })
+  @ApiOkResponse({ description: '登录成功返回 token', type: ClientLoginResponseDto })
  async smsLogin(@Body() body: ClientLoginDto) {
    return this.clientAuthService.loginBySms(body.phone, body.code);
  }

  @Post('refresh')
  @ApiOperation({ summary: '刷新客户端 access token' })
-  @ApiBody({
-    schema: {
-      type: 'object',
-      description: 'refresh token 刷新请求体',
-      properties: {
-        refreshToken: { type: 'string', description: '刷新令牌' },
-      },
-      required: ['refreshToken'],
-    },
-  })
-  @ApiOkResponse({
-    description: '刷新成功返回新 token',
-    schema: {
-      type: 'object',
-      properties: {
-        accessToken: { type: 'string' },
-        refreshToken: { type: 'string' },
-      },
-    },
-  })
+  @ApiBody({ type: ClientRefreshDto })
+  @ApiOkResponse({ description: '刷新成功返回新 token', type: ClientRefreshResponseDto })
  async refresh(@Body() body: ClientRefreshDto) {
    return this.clientAuthService.refreshToken(body.refreshToken);
  }
--- a/src/apps/client-app/auth/dto/client-auth-response.dto.ts
+++ b/src/apps/client-app/auth/dto/client-auth-response.dto.ts
@@ -0,0 +1,58 @@
+import { ApiProperty, ApiPropertyOptional } from '@nestjs/swagger';
+
+export class ClientSendSmsResponseDto {
+  @ApiProperty({ type: String, example: 'sms_1710000000000' })
+  requestId!: string;
+
+  @ApiProperty({ type: String, example: '13800000000' })
+  phone!: string;
+
+  @ApiProperty({ type: String, example: 'login' })
+  scene!: string;
+
+  @ApiProperty({ type: String, description: '短信渠道标识' })
+  provider!: string;
+
+  @ApiProperty({ type: Number, example: 300, description: '验证码有效期（秒）' })
+  expireIn!: number;
+
+  @ApiPropertyOptional({
+    type: String,
+    description: '非生产环境返回，便于联调',
+    example: '123456',
+  })
+  testCode?: string;
+}
+
+export class ClientAuthUserDto {
+  @ApiProperty({ type: String, example: '1', description: '用户 ID（数字字符串）' })
+  id!: string;
+
+  @ApiProperty({ type: String, example: '13800000000' })
+  phone!: string;
+
+  @ApiProperty({ type: String, example: 'Chat0000' })
+  nickname!: string;
+
+  @ApiProperty({ type: String, example: 'https://example.com/a.png' })
+  avatarUrl!: string;
+}
+
+export class ClientLoginResponseDto {
+  @ApiProperty({ type: String })
+  accessToken!: string;
+
+  @ApiProperty({ type: String })
+  refreshToken!: string;
+
+  @ApiProperty({ type: () => ClientAuthUserDto })
+  user!: ClientAuthUserDto;
+}
+
+export class ClientRefreshResponseDto {
+  @ApiProperty({ type: String })
+  accessToken!: string;
+
+  @ApiProperty({ type: String })
+  refreshToken!: string;
+}
--- a/src/apps/client-app/auth/dto/login.dto.ts
+++ b/src/apps/client-app/auth/dto/login.dto.ts
@@ -1,26 +1,32 @@
+import { ApiProperty } from '@nestjs/swagger';
 import { IsNotEmpty, IsString } from 'class-validator';

 export class ClientSendSmsDto {
+  @ApiProperty({ type: String, description: '手机号', example: '13800000000' })
  @IsString()
  @IsNotEmpty()
  phone!: string;

+  @ApiProperty({ type: String, description: '业务场景', example: 'login' })
  @IsString()
  @IsNotEmpty()
  scene!: string;
 }

 export class ClientLoginDto {
+  @ApiProperty({ type: String, description: '手机号', example: '13800000000' })
  @IsString()
  @IsNotEmpty()
  phone!: string;

+  @ApiProperty({ type: String, description: '短信验证码', example: '123456' })
  @IsString()
  @IsNotEmpty()
  code!: string;
 }

 export class ClientRefreshDto {
+  @ApiProperty({ type: String, description: '刷新令牌' })
  @IsString()
  @IsNotEmpty()
  refreshToken!: string;
--- a/src/apps/client-app/chat/application/chat-session.service.ts
+++ b/src/apps/client-app/chat/application/chat-session.service.ts
@@ -0,0 +1,260 @@
+import {
+  BadRequestException,
+  ForbiddenException,
+  Inject,
+  Injectable,
+  NotFoundException,
+} from '@nestjs/common';
+import { PrismaService } from '@prisma/prisma.service';
+import {
+  ChatMessage,
+  ProviderUsage,
+  StreamChatRequest,
+} from '@shared/ai-gateway/types/chat.types';
+import { Prisma } from '@prisma/client';
+
+function parseBigIntId(value: string, field: string): bigint {
+  try {
+    return BigInt(value.trim());
+  } catch {
+    throw new BadRequestException(`${field} 格式无效`);
+  }
+}
+
+@Injectable()
+export class ChatSessionService {
+  constructor(@Inject(PrismaService) private readonly prisma: PrismaService) {}
+
+  async createSession(userId: bigint, title?: string | null) {
+    const row = await this.prisma.chatSession.create({
+      data: {
+        userId,
+        title: title?.trim() || null,
+      },
+    });
+    return this.mapSession(row);
+  }
+
+  async listSessions(userId: bigint, limit: number, offset: number) {
+    const take = Math.min(100, Math.max(1, limit));
+    const skip = Math.max(0, offset);
+    const [rows, total] = await Promise.all([
+      this.prisma.chatSession.findMany({
+        where: { userId },
+        orderBy: { updatedAt: 'desc' },
+        take,
+        skip,
+      }),
+      this.prisma.chatSession.count({ where: { userId } }),
+    ]);
+    return {
+      items: rows.map((r) => this.mapSession(r)),
+      total,
+      limit: take,
+      offset: skip,
+    };
+  }
+
+  async listMessages(
+    userId: bigint,
+    sessionIdStr: string,
+    limit: number,
+    offset: number,
+  ) {
+    const sessionId = parseBigIntId(sessionIdStr, 'sessionId');
+    await this.assertSessionOwned(userId, sessionId);
+    const take = Math.min(100, Math.max(1, limit));
+    const skip = Math.max(0, offset);
+
+    const [rows, total] = await Promise.all([
+      this.prisma.chatMessage.findMany({
+        where: { sessionId },
+        orderBy: { id: 'asc' },
+        take,
+        skip,
+      }),
+      this.prisma.chatMessage.count({ where: { sessionId } }),
+    ]);
+
+    return {
+      sessionId: String(sessionId),
+      items: rows.map((m) => ({
+        id: String(m.id),
+        role: m.role,
+        content: m.content,
+        tokenCount: m.tokenCount,
+        provider: m.provider,
+        createdAt: m.createdAt.toISOString(),
+      })),
+      total,
+      limit: take,
+      offset: skip,
+    };
+  }
+
+  async deleteSession(userId: bigint, sessionIdStr: string) {
+    const sessionId = parseBigIntId(sessionIdStr, 'sessionId');
+    await this.assertSessionOwned(userId, sessionId);
+    const deleted = await this.prisma.chatSession.delete({
+      where: { id: sessionId },
+    });
+    return this.mapSession(deleted);
+  }
+
+  async updateSessionTitle(userId: bigint, sessionIdStr: string, title: string) {
+    const sessionId = parseBigIntId(sessionIdStr, 'sessionId');
+    await this.assertSessionOwned(userId, sessionId);
+    const updated = await this.prisma.chatSession.update({
+      where: { id: sessionId },
+      data: { title: title.trim() || null },
+    });
+    return this.mapSession(updated);
+  }
+
+  /**
+   * 解析并校验会话；stream 场景必须传入 sessionId
+   */
+  async resolveSessionForStream(
+    userId: bigint,
+    body: StreamChatRequest,
+  ): Promise<bigint> {
+    const raw = body.sessionId?.trim();
+    if (!raw) {
+      throw new BadRequestException('sessionId 必填，请先创建会话');
+    }
+    const sessionId = parseBigIntId(raw, 'sessionId');
+    await this.assertSessionOwned(userId, sessionId);
+    return sessionId;
+  }
+
+  async persistRoundtrip(
+    sessionId: bigint,
+    messages: ChatMessage[],
+    assistantText: string,
+    providerCode: string,
+    usage: ProviderUsage,
+  ) {
+    const lastUser = [...messages].reverse().find((m) => m.role === 'user');
+    if (lastUser?.content) {
+      await this.prisma.chatMessage.create({
+        data: {
+          sessionId,
+          role: 'user',
+          content: lastUser.content,
+          tokenCount: 0,
+          provider: null,
+        },
+      });
+      const session = await this.prisma.chatSession.findUnique({
+        where: { id: sessionId },
+        select: { title: true },
+      });
+      if (session && !session.title) {
+        const t = lastUser.content.trim().slice(0, 80);
+        if (t) {
+          await this.prisma.chatSession.update({
+            where: { id: sessionId },
+            data: { title: t },
+          });
+        }
+      }
+    }
+
+    await this.prisma.chatMessage.create({
+      data: {
+        sessionId,
+        role: 'assistant',
+        content: assistantText,
+        tokenCount: usage.completionTokens ?? 0,
+        provider: providerCode,
+      },
+    });
+
+    await this.prisma.$executeRaw(
+      Prisma.sql`UPDATE chat_sessions SET updated_at = NOW() WHERE id = ${sessionId}`,
+    );
+  }
+
+  /**
+   * 为了让前端在 SSE 结束后立即看到会话标题，先持久化用户消息与标题。
+   */
+  async persistUserMessageAndTitle(sessionId: bigint, messages: ChatMessage[]) {
+    const lastUser = [...messages].reverse().find((m) => m.role === 'user');
+    if (!lastUser?.content) return;
+
+    await this.prisma.chatMessage.create({
+      data: {
+        sessionId,
+        role: 'user',
+        content: lastUser.content,
+        tokenCount: 0,
+        provider: null,
+      },
+    });
+
+    const title = lastUser.content.trim().slice(0, 80);
+    if (title) {
+      await this.prisma.chatSession.updateMany({
+        where: {
+          id: sessionId,
+          OR: [{ title: null }, { title: '' }],
+        },
+        data: { title },
+      });
+    }
+
+    await this.prisma.$executeRaw(
+      Prisma.sql`UPDATE chat_sessions SET updated_at = NOW() WHERE id = ${sessionId}`,
+    );
+  }
+
+  async persistAssistantMessage(
+    sessionId: bigint,
+    assistantText: string,
+    providerCode: string,
+    usage: ProviderUsage,
+  ) {
+    await this.prisma.chatMessage.create({
+      data: {
+        sessionId,
+        role: 'assistant',
+        content: assistantText,
+        tokenCount: usage.completionTokens ?? 0,
+        provider: providerCode,
+      },
+    });
+
+    await this.prisma.$executeRaw(
+      Prisma.sql`UPDATE chat_sessions SET updated_at = NOW() WHERE id = ${sessionId}`,
+    );
+  }
+
+  private async assertSessionOwned(userId: bigint, sessionId: bigint) {
+    const row = await this.prisma.chatSession.findUnique({
+      where: { id: sessionId },
+      select: { userId: true },
+    });
+    if (!row) {
+      throw new NotFoundException('会话不存在');
+    }
+    if (row.userId !== userId) {
+      throw new ForbiddenException('无权访问该会话');
+    }
+  }
+
+  private mapSession(row: {
+    id: bigint;
+    userId: bigint;
+    title: string | null;
+    createdAt: Date;
+    updatedAt: Date;
+  }) {
+    return {
+      id: String(row.id),
+      userId: String(row.userId),
+      title: row.title ?? '',
+      createdAt: row.createdAt.toISOString(),
+      updatedAt: row.updatedAt.toISOString(),
+    };
+  }
+}
--- a/src/apps/client-app/chat/chat.module.ts
+++ b/src/apps/client-app/chat/chat.module.ts
@@ -1,13 +1,21 @@
 import { Module } from '@nestjs/common';
 import { ChatController } from './controllers/chat.controller';
+import { ChatSessionsController } from './controllers/chat-sessions.controller';
+import { ChatSessionService } from './application/chat-session.service';
 import { ProviderRouterService } from '@shared/ai-gateway/router/provider-router.service';
 import { QwenProvider } from '@shared/ai-gateway/providers/qwen.provider';
 import { DeepseekProvider } from '@shared/ai-gateway/providers/deepseek.provider';
 import { VolcProvider } from '@shared/ai-gateway/providers/volc.provider';

@Module({
-  controllers: [ChatController],
-  providers: [ProviderRouterService, QwenProvider, DeepseekProvider, VolcProvider],
+  controllers: [ChatController, ChatSessionsController],
+  providers: [
+    ChatSessionService,
+    ProviderRouterService,
+    QwenProvider,
+    DeepseekProvider,
+    VolcProvider,
+  ],
 })
 export class ChatModule {}

--- a/src/apps/client-app/chat/controllers/chat-sessions.controller.ts
+++ b/src/apps/client-app/chat/controllers/chat-sessions.controller.ts
@@ -0,0 +1,143 @@
+import {
+  Body,
+  Controller,
+  Delete,
+  Get,
+  Inject,
+  Patch,
+  Param,
+  Post,
+  Query,
+  Req,
+  UseGuards,
+  UsePipes,
+  ValidationPipe,
+} from '@nestjs/common';
+import {
+  ApiBearerAuth,
+  ApiBody,
+  ApiOkResponse,
+  ApiOperation,
+  ApiParam,
+  ApiTags,
+} from '@nestjs/swagger';
+import type { FastifyRequest } from 'fastify';
+import { ClientJwtAuthGuard } from '../../auth/client-jwt-auth.guard';
+import { ChatSessionService } from '../application/chat-session.service';
+import { PaginationQueryDto } from '../dto/chat-session-query.dto';
+import {
+  ChatMessageListResponseDto,
+  ChatSessionListResponseDto,
+  ChatSessionRowDto,
+} from '../dto/chat-session-response.dto';
+import { CreateChatSessionDto } from '../dto/create-chat-session.dto';
+import { UpdateChatSessionTitleDto } from '../dto/update-chat-session-title.dto';
+
+type ClientJwtRequest = FastifyRequest & { user: { userId: string } };
+
+@ApiTags('Client Chat')
+@ApiBearerAuth('access-token')
+@Controller('client/v1/chat/sessions')
+@UseGuards(ClientJwtAuthGuard)
+export class ChatSessionsController {
+  constructor(
+    @Inject(ChatSessionService)
+    private readonly chatSessions: ChatSessionService,
+  ) {}
+
+  @Post()
+  @UsePipes(
+    new ValidationPipe({
+      whitelist: true,
+      transform: true,
+    }),
+  )
+  @ApiOperation({ summary: '创建空会话' })
+  @ApiBody({ type: CreateChatSessionDto })
+  @ApiOkResponse({ type: ChatSessionRowDto })
+  async create(@Req() req: ClientJwtRequest, @Body() body: CreateChatSessionDto) {
+    const userId = BigInt(req.user.userId);
+    return this.chatSessions.createSession(userId, body.title);
+  }
+
+  @Get()
+  @UsePipes(
+    new ValidationPipe({
+      whitelist: true,
+      transform: true,
+    }),
+  )
+  @ApiOperation({ summary: '会话列表' })
+  @ApiOkResponse({ type: ChatSessionListResponseDto })
+  async list(@Req() req: ClientJwtRequest, @Query() query: PaginationQueryDto) {
+    const userId = BigInt(req.user.userId);
+    const limit = Math.min(100, Math.max(1, query.limit ?? 20));
+    const offset = Math.max(0, query.offset ?? 0);
+    return this.chatSessions.listSessions(userId, limit, offset);
+  }
+
+  @Get(':sessionId/messages')
+  @UsePipes(
+    new ValidationPipe({
+      whitelist: true,
+      transform: true,
+    }),
+  )
+  @ApiOperation({ summary: '会话消息分页' })
+  @ApiParam({
+    name: 'sessionId',
+    description: '会话 ID（数字字符串）',
+    example: '1',
+  })
+  @ApiOkResponse({ type: ChatMessageListResponseDto })
+  async messages(
+    @Req() req: ClientJwtRequest,
+    @Param('sessionId') sessionId: string,
+    @Query() query: PaginationQueryDto,
+  ) {
+    const userId = BigInt(req.user.userId);
+    const limit = Math.min(100, Math.max(1, query.limit ?? 50));
+    const offset = Math.max(0, query.offset ?? 0);
+    return this.chatSessions.listMessages(userId, sessionId, limit, offset);
+  }
+
+  @Delete(':sessionId')
+  @ApiOperation({ summary: '删除会话（级联删除消息）' })
+  @ApiParam({
+    name: 'sessionId',
+    description: '会话 ID（数字字符串）',
+    example: '1',
+  })
+  @ApiOkResponse({ type: ChatSessionRowDto })
+  async remove(
+    @Req() req: ClientJwtRequest,
+    @Param('sessionId') sessionId: string,
+  ) {
+    const userId = BigInt(req.user.userId);
+    return this.chatSessions.deleteSession(userId, sessionId);
+  }
+
+  @Patch(':sessionId/title')
+  @UsePipes(
+    new ValidationPipe({
+      whitelist: true,
+      transform: true,
+    }),
+  )
+  @ApiOperation({ summary: '修改会话标题' })
+  @ApiParam({
+    name: 'sessionId',
+    description: '会话 ID（数字字符串）',
+    example: '1',
+  })
+  @ApiBody({ type: UpdateChatSessionTitleDto })
+  @ApiOkResponse({ type: ChatSessionRowDto })
+  async updateTitle(
+    @Req() req: ClientJwtRequest,
+    @Param('sessionId') sessionId: string,
+    @Body() body: UpdateChatSessionTitleDto,
+  ) {
+    const userId = BigInt(req.user.userId);
+    return this.chatSessions.updateSessionTitle(userId, sessionId, body.title);
+  }
+}
--- a/src/apps/client-app/chat/controllers/chat.controller.ts
+++ b/src/apps/client-app/chat/controllers/chat.controller.ts
@@ -1,8 +1,20 @@
-import { Body, Controller, Inject, Post, Res, UseGuards } from '@nestjs/common';
-import { FastifyReply } from 'fastify';
-import { StreamChatRequest } from '@shared/ai-gateway/types/chat.types';
+import {
+  Body,
+  Controller,
+  Inject,
+  Logger,
+  Post,
+  Req,
+  Res,
+  UseGuards,
+  UsePipes,
+  ValidationPipe,
+} from '@nestjs/common';
+import type { FastifyReply, FastifyRequest } from 'fastify';
 import { ProviderRouterService } from '@shared/ai-gateway/router/provider-router.service';
 import { ClientJwtAuthGuard } from '../../auth/client-jwt-auth.guard';
+import { ChatSessionService } from '../application/chat-session.service';
+import { StreamChatBodyDto } from '../dto/stream-chat.dto';
 import {
  ApiBearerAuth,
  ApiBody,
@@ -21,13 +33,19 @@ function sleep(ms: number) {
  return new Promise((resolve) => setTimeout(resolve, ms));
 }

+type ClientJwtRequest = FastifyRequest & { user: { userId: string } };
+
@ApiTags('Client Chat')
@ApiBearerAuth('access-token')
@Controller('client/v1/chat')
 export class ChatController {
+  private readonly logger = new Logger(ChatController.name);
+
  constructor(
    @Inject(ProviderRouterService)
    private readonly router: ProviderRouterService,
+    @Inject(ChatSessionService)
+    private readonly chatSessions: ChatSessionService,
  ) {}

  @Post('completions/stream')
@@ -36,62 +54,41 @@ export class ChatController {
  @ApiConsumes('application/json')
  @ApiProduces('text/event-stream')
  @ApiBody({
-    schema: {
-      type: 'object',
-      description: '统一 chat 请求体，支持指定平台或自动路由',
-      properties: {
-        model: {
-          type: 'string',
-          description: '模型名（不传时 provider 使用默认模型）',
-          example: 'qwen-plus',
-        },
-        platform: {
-          type: 'string',
-          description: '目标平台（auto 或不传表示自动路由）',
-          enum: ['auto', 'qwen', 'deepseek', 'volc'],
-          example: 'qwen',
-        },
-        messages: {
-          type: 'array',
-          description: '聊天消息列表',
-          items: {
-            type: 'object',
-            properties: {
-              role: {
-                type: 'string',
-                description: '消息角色',
-                enum: ['system', 'user', 'assistant'],
-                example: 'user',
-              },
-              content: {
-                type: 'string',
-                description: '消息文本内容',
-                example: '你是谁',
-              },
-            },
-            required: ['role', 'content'],
-          },
-        },
-      },
-      required: ['messages'],
-    },
+    type: StreamChatBodyDto,
+    description: '统一 chat 请求体；需先手动创建会话并传入 sessionId',
  })
  @ApiOkResponse({
-    description: 'SSE 流式响应：meta -> delta -> usage -> done',
-    schema: {
-      type: 'string',
-      example:
-        'event: meta\\ndata: {"requestId":"chatcmpl_xxx","platform":"qwen","model":"qwen-plus"}\\n\\n' +
-        'event: delta\\ndata: {"delta":"你好"}\\n\\n' +
-        'event: usage\\ndata: {"promptTokens":10,"completionTokens":20,"totalTokens":30}\\n\\n' +
-        'event: done\\ndata: {"finishReason":"stop"}\\n\\n',
+    description:
+      'SSE 流式响应：event 序列为 meta → delta（多次）→ usage → done',
+    content: {
+      'text/event-stream': {
+        schema: {
+          type: 'string',
+          example:
+            'event: meta\\ndata: {"requestId":"chatcmpl_xxx","platform":"qwen","model":"qwen-plus","sessionId":"1"}\\n\\n' +
+            'event: delta\\ndata: {"delta":"你好"}\\n\\n' +
+            'event: usage\\ndata: {"promptTokens":10,"completionTokens":20,"totalTokens":30}\\n\\n' +
+            'event: done\\ndata: {"finishReason":"stop"}\\n\\n',
+        },
+      },
    },
  })
+  @UsePipes(
+    new ValidationPipe({
+      whitelist: true,
+      transform: true,
+    }),
+  )
  async streamChat(
-    @Body() body: StreamChatRequest,
+    @Body() body: StreamChatBodyDto,
+    @Req() req: ClientJwtRequest,
    @Res() reply: FastifyReply,
  ) {
-    const response = await this.router.routeAndStream(body);
+    const userId = BigInt(req.user.userId);
+    const sessionId = await this.chatSessions.resolveSessionForStream(
+      userId,
+      body,
+    );

    reply.raw.setHeader('Content-Type', 'text/event-stream; charset=utf-8');
    reply.raw.setHeader('Cache-Control', 'no-cache, no-transform');
@@ -99,22 +96,51 @@ export class ChatController {
    reply.raw.setHeader('X-Accel-Buffering', 'no');
    reply.raw.flushHeaders?.();

+    const response = await this.router.routeAndStream(body);
+
    reply.raw.write(
      formatSse('meta', {
        requestId: response.requestId,
        platform: response.providerCode,
        model: response.model,
+        sessionId: String(sessionId),
      }),
    );

+    let assistantText = '';
    for (const chunk of response.chunks) {
+      assistantText += chunk.content;
      reply.raw.write(formatSse('delta', { delta: chunk.content }));
      await sleep(120);
    }

+    // 在 done 之前完成用户消息与标题落库，确保前端紧接着查列表能看到最新标题。
+    try {
+      await this.chatSessions.persistUserMessageAndTitle(sessionId, body.messages);
+    } catch (err) {
+      this.logger.error(
+        { err, sessionId: String(sessionId) },
+        'persist user message/title failed',
+      );
+    }
+
    reply.raw.write(formatSse('usage', response.usage));
    reply.raw.write(formatSse('done', { finishReason: 'stop' }));
    reply.raw.end();
+
+    try {
+      await this.chatSessions.persistAssistantMessage(
+        sessionId,
+        assistantText,
+        response.providerCode,
+        response.usage,
+      );
+    } catch (err) {
+      this.logger.error(
+        { err, sessionId: String(sessionId) },
+        'persist chat roundtrip failed',
+      );
+    }
  }
 }

--- a/src/apps/client-app/chat/dto/chat-session-query.dto.ts
+++ b/src/apps/client-app/chat/dto/chat-session-query.dto.ts
@@ -0,0 +1,32 @@
+import { ApiPropertyOptional } from '@nestjs/swagger';
+import { Type } from 'class-transformer';
+import { IsInt, IsOptional, Max, Min } from 'class-validator';
+
+/** 会话列表、消息列表共用的分页查询（limit 默认值在控制器中按路由区分） */
+export class PaginationQueryDto {
+  @ApiPropertyOptional({
+    type: Number,
+    minimum: 1,
+    maximum: 100,
+    description: '分页条数；会话列表默认 20，消息列表默认 50',
+    example: 20,
+  })
+  @IsOptional()
+  @Type(() => Number)
+  @IsInt()
+  @Min(1)
+  @Max(100)
+  limit?: number;
+
+  @ApiPropertyOptional({
+    type: Number,
+    minimum: 0,
+    description: '偏移量',
+    example: 0,
+  })
+  @IsOptional()
+  @Type(() => Number)
+  @IsInt()
+  @Min(0)
+  offset?: number;
+}
--- a/src/apps/client-app/chat/dto/chat-session-response.dto.ts
+++ b/src/apps/client-app/chat/dto/chat-session-response.dto.ts
@@ -0,0 +1,80 @@
+import { ApiProperty, ApiPropertyOptional } from '@nestjs/swagger';
+
+export class ChatSessionRowDto {
+  @ApiProperty({ type: String, example: '1', description: '会话 ID（数字字符串）' })
+  id!: string;
+
+  @ApiProperty({ type: String, example: '1', description: '用户 ID（数字字符串）' })
+  userId!: string;
+
+  @ApiProperty({
+    type: String,
+    description: '标题（可能为空字符串）',
+    example: '你好',
+  })
+  title!: string;
+
+  @ApiProperty({ type: String, description: '创建时间 ISO8601' })
+  createdAt!: string;
+
+  @ApiProperty({ type: String, description: '更新时间 ISO8601' })
+  updatedAt!: string;
+}
+
+export class ChatSessionListResponseDto {
+  @ApiProperty({ type: () => ChatSessionRowDto, isArray: true })
+  items!: ChatSessionRowDto[];
+
+  @ApiProperty({ type: Number })
+  total!: number;
+
+  @ApiProperty({ type: Number })
+  limit!: number;
+
+  @ApiProperty({ type: Number })
+  offset!: number;
+}
+
+export class ChatMessageRowDto {
+  @ApiProperty({ type: String, example: '1', description: '消息 ID（数字字符串）' })
+  id!: string;
+
+  @ApiProperty({ type: String, example: 'user' })
+  role!: string;
+
+  @ApiProperty({ type: String })
+  content!: string;
+
+  @ApiProperty({
+    type: Number,
+    description: 'completion token 数（用户消息为 0）',
+  })
+  tokenCount!: number;
+
+  @ApiPropertyOptional({
+    type: String,
+    nullable: true,
+    description: '大模型渠道（用户消息一般为 null）',
+  })
+  provider?: string | null;
+
+  @ApiProperty({ type: String, description: '创建时间 ISO8601' })
+  createdAt!: string;
+}
+
+export class ChatMessageListResponseDto {
+  @ApiProperty({ type: String, example: '1' })
+  sessionId!: string;
+
+  @ApiProperty({ type: () => ChatMessageRowDto, isArray: true })
+  items!: ChatMessageRowDto[];
+
+  @ApiProperty({ type: Number })
+  total!: number;
+
+  @ApiProperty({ type: Number })
+  limit!: number;
+
+  @ApiProperty({ type: Number })
+  offset!: number;
+}
--- a/src/apps/client-app/chat/dto/create-chat-session.dto.ts
+++ b/src/apps/client-app/chat/dto/create-chat-session.dto.ts
@@ -0,0 +1,10 @@
+import { ApiPropertyOptional } from '@nestjs/swagger';
+import { IsOptional, IsString, MaxLength } from 'class-validator';
+
+export class CreateChatSessionDto {
+  @ApiPropertyOptional({ type: String, description: '会话标题', maxLength: 200 })
+  @IsOptional()
+  @IsString()
+  @MaxLength(200)
+  title?: string;
+}
--- a/src/apps/client-app/chat/dto/stream-chat.dto.ts
+++ b/src/apps/client-app/chat/dto/stream-chat.dto.ts
@@ -3,24 +3,38 @@ import { Type } from 'class-transformer';
 import { IsArray, IsIn, IsOptional, IsString, ValidateNested } from 'class-validator';
 import { StreamChatRequest } from '@shared/ai-gateway/types/chat.types';

-class ChatMessageDto {
-  @ApiProperty({ enum: ['system', 'user', 'assistant'] })
+export class ChatMessageDto {
+  @ApiProperty({
+    type: String,
+    enum: ['system', 'user', 'assistant'],
+    description: '消息角色',
+    example: 'user',
+  })
  @IsString()
  @IsIn(['system', 'user', 'assistant'])
  role!: 'system' | 'user' | 'assistant';

-  @ApiProperty({ description: '消息内容', example: '你是谁' })
+  @ApiProperty({ type: String, description: '消息内容', example: '你是谁' })
  @IsString()
  content!: string;
 }

 export class StreamChatBodyDto implements StreamChatRequest {
-  @ApiPropertyOptional({ description: '模型名', example: 'qwen-plus' })
+  @ApiPropertyOptional({ type: String, description: '模型名', example: 'qwen-plus' })
  @IsOptional()
  @IsString()
  model?: string;

+  @ApiProperty({
+    type: String,
+    description: '会话 ID（数字字符串）；需先调用创建会话接口获取',
+    example: '1',
+  })
+  @IsString()
+  sessionId!: string;
+
  @ApiPropertyOptional({
+    type: String,
    description: '指定平台，不传或 auto 由路由自动选择',
    enum: ['auto', 'qwen', 'deepseek', 'volc'],
    example: 'qwen',
@@ -29,7 +43,11 @@ export class StreamChatBodyDto implements StreamChatRequest {
  @IsString()
  platform?: string;

-  @ApiProperty({ type: [ChatMessageDto] })
+  @ApiProperty({
+    type: () => ChatMessageDto,
+    isArray: true,
+    description: '聊天消息列表（至少一条用户消息）',
+  })
  @IsArray()
  @ValidateNested({ each: true })
  @Type(() => ChatMessageDto)
--- a/src/apps/client-app/chat/dto/update-chat-session-title.dto.ts
+++ b/src/apps/client-app/chat/dto/update-chat-session-title.dto.ts
@@ -0,0 +1,14 @@
+import { ApiProperty } from '@nestjs/swagger';
+import { IsString, MaxLength } from 'class-validator';
+
+export class UpdateChatSessionTitleDto {
+  @ApiProperty({
+    type: String,
+    description: '会话标题（可传空字符串清空）',
+    maxLength: 200,
+    example: '产品需求讨论',
+  })
+  @IsString()
+  @MaxLength(200)
+  title!: string;
+}
--- a/src/apps/shared-domain/ai-gateway/types/chat.types.ts
+++ b/src/apps/shared-domain/ai-gateway/types/chat.types.ts
@@ -8,6 +8,8 @@ export interface ChatMessage {
 export interface StreamChatRequest {
  model?: string;
  platform?: string; // qwen | deepseek | volc | auto | demo
+  /** 已有会话 ID；不传则本次对话新建会话并落库 */
+  sessionId?: string;
  messages: ChatMessage[];
 }