cicd

issue observers

Наблюдатели задачи видят её и комментируют, но не редактируют.

- таблица issue_observer, наблюдатели — часть сущности Issue
- видимость: reporter, assignee или наблюдатель (задачи, история, SSE)
- правка/удаление задачи и вложений — только reporter/assignee (403 наблюдателю)
- observers в create/update, DELETE /issues/:id/observers/me, фильтр role
- история изменений и уведомления новым наблюдателям

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.dockerignore

@@ -10,3 +10,6 @@ coverage
 *.log
 tsconfig.build.tsbuildinfo
 src/generated
+storage
+configs
+service-account.json

.gitea/workflows/deploy.yaml

@@ -1,4 +1,4 @@
-name: Gitea Actions Demo
+name: Gitea Actions
 run-name: Deploy 🚀
 on:
   push:
@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
       - name: Docker build
         run: docker build --tag ${{ env.IMAGE_NAME }} .
       - name: Login to gitea

.gitignore

@@ -2,6 +2,7 @@
 /dist
 /node_modules
 /build
+*.tsbuildinfo
 
 # Logs
 logs
@@ -57,3 +58,8 @@ report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json
 
 /src/generated/prisma
 /src/schema.gql
+
+# Local file storage (FILE_STORAGE=local)
+/storage
+/configs
+configs/service-account.json

README_PRISMA.md

@@ -1,3 +1,4 @@
+# Prisma
 
 npm install prisma@7 --save-dev
 

WIP.md

@@ -0,0 +1,214 @@
+# WIP — вложения (2026-10-02)
+
+Сделано за сегодня: модуль `file` (хранение файлов), модуль `issue-attachment`
+(вложения задач) и вложения в комментариях. Всё в ветке `feature/attachments`
+(не запушена), миграции к БД не применялись.
+
+## Архитектура
+
+Метаданные файла хранятся отдельно от того, к чему файл прикреплён:
+
+```
+file  ←──  issue_attachment    (issueId, fileId)    — модуль issue-attachment
+      ←──  comment_attachment  (commentId, fileId)  — модуль comment
+```
+
+- `file` ничего не знает о владельцах. Новый владелец = своя таблица связей
+  + регистрация в `FileOwnerRegistry`; сам `file` при этом не меняется.
+- Удаление задачи/комментария удаляет связи каскадом в БД, а файл без единой
+  связи (сирота) удаляет GC.
+- Флоу для клиента в два шага: загрузить файл → прикрепить по `fileId`.
+
+Почему не полиморфная связь `ownerType + ownerId`: нет FK, нет каскадов, разные
+типы ключей (`Issue.id` — Int, остальные — uuid).
+
+## Миграции
+
+| Миграция | Что |
+|---|---|
+| `20261002045355_file` | таблица `file` |
+| `20261002050156_issue_attachment` | таблица `issue_attachment` |
+| `20261002060755_comment_attachment` | таблица `comment_attachment` |
+
+Собраны через `prisma migrate diff` без подключения к БД. Применятся при деплое
+(`prisma migrate deploy` в CMD Dockerfile).
+
+## Модуль `file` — `src/modules/file/`
+
+### API
+
+| Метод | Путь | Что |
+|---|---|---|
+| POST | `/api/files` | загрузка, multipart, поле `file` → `FileDto` |
+| GET | `/api/files/:id/download` | скачивание (поток) |
+| DELETE | `/api/files/:id` | удалить файл (только загрузивший), 204 |
+
+`FileDto`: `{ id, fileName, mimeType, size, uploaderId, createdAt }`.
+`storageKey` наружу не отдаётся.
+
+### Устройство
+
+- **domain**:
+  - `StoredFile` — не `File`, чтобы не путать с глобальным Web API `File`;
+  - VO `FileName`: убирает путь и управляющие символы, обрезает до 255
+    с сохранением расширения;
+  - порты `IFileStorage`, `IFileTypeDetector`.
+- **application**:
+  - use-case'ы upload / download / delete / get-files;
+  - `FileAccessService`, `FileOwnerRegistry`, `FileGcService`.
+- **infrastructure**:
+  - `FilePrismaRepository`;
+  - хранилища `LocalFileStorage` (dev/тесты) и `S3FileStorage`
+    (S3 / RustFS / MinIO), выбираются в `file-storage.factory.ts`;
+  - `FileTypeDetector` на `file-type`.
+- **presentation**: `FileController`, хелпер `contentDisposition`
+  (RFC 5987, кириллица), GraphQL-тип `File`.
+
+### Загрузка
+
+- multer пишет во временный файл (`os.tmpdir()`), а не в память. Лимит —
+  `FILE_MAX_SIZE_MB`, при превышении Nest отвечает 413.
+- `defParamCharset: 'utf8'` — иначе multer ломает кириллицу в именах файлов.
+- MIME определяется **по содержимому** (magic bytes). Нераспознанное
+  (HTML, SVG, текст) сохраняется как `application/octet-stream`.
+- Ключ в хранилище — `files/{randomUUID}`. Имя от пользователя в ключ не попадает.
+- Порядок записи: объект → строка в БД. Если запись строки упала, объект
+  удаляется сразу.
+
+### Скачивание и безопасность
+
+- Inline отдаются только `image/png|jpeg|gif|webp`, всё остальное — как
+  `attachment`. Плюс `X-Content-Type-Options: nosniff` — защита от stored XSS.
+- Файл виден загрузившему и всем, кому виден хоть один его владелец (задача,
+  комментарий). Иначе 404, чтобы не раскрывать существование файла.
+- `TransformResponseInterceptor` пропускает `StreamableFile`. Без этого обёртка
+  `{data, code}` ломала скачивание.
+
+### Прикрепление (для модулей-владельцев)
+
+- `FileAccessService.getAttachableFile(id, userId)`: прикрепить можно только
+  **свой** файл. Невидимый файл → 404, чужой → 403. Иначе файл, увиденный
+  через одну задачу, можно было бы перенести в другую.
+- `GetFilesUseCase` — метаданные файлов по id, для раскрытия связей в DTO.
+
+### GC файлов-сирот
+
+- `FileGcService`, `@Cron(EVERY_HOUR)`. Подключён `ScheduleModule` в `app.module.ts`.
+- Удаляет файлы старше `FILE_ORPHAN_TTL_HOURS` (по умолчанию 24), на которые
+  не ссылается ни один зарегистрированный владелец.
+- Порядок удаления: объект → строка. Удаление объекта идемпотентно, поэтому
+  при сбое следующий запуск доделает работу. Тот же порядок в `DeleteFileUseCase`.
+- Безопасен при нескольких инстансах приложения.
+
+> ⚠️ Новый владелец файлов **обязан** зарегистрироваться в `FileOwnerRegistry`
+> (`onModuleInit`), иначе GC удалит его файлы как сирот.
+
+## Модуль `issue-attachment` — `src/modules/issue-attachment/`
+
+Отдельный модуль, как `comment`: зависит от issue, а issue о нём не знает.
+Иначе получался бы цикл issue ↔ attachment.
+
+### API
+
+| Метод | Путь | Что |
+|---|---|---|
+| GET | `/api/issues/:issueId/attachments` | список → `IssueAttachmentDto[]` |
+| POST | `/api/issues/:issueId/attachments` | `{ fileId }` → `IssueAttachmentDto` |
+| DELETE | `/api/issues/:issueId/attachments/:fileId` | открепить, 204 (файл удалит GC) |
+
+`IssueAttachmentDto`: `{ issueId, file: FileDto, attachedAt }`.
+
+GraphQL: поле `IssueDetail.attachments`. Его добавляет `IssueAttachmentResolver`
+через `@ResolveField`, issue-модуль не тронут. В списке задач (`Issue`) этого
+поля нет, чтобы не было N+1.
+
+### Правила
+
+- Прикреплять и откреплять может любой, кому видна задача (то же правило, что
+  для правки задачи), но прикрепить можно только свой файл.
+- Повторное прикрепление идемпотентно (`upsert`).
+- Если задачу или файл удалили между проверкой и вставкой (FK violation), ответ 404.
+- `IssueAttachmentFileOwnerService` регистрируется в реестре. Видимость файла
+  проверяется через `IIssueRepository.findById`, поэтому правило
+  «reporter/assignee» живёт в одном месте.
+
+## Вложения в комментариях — модуль `comment`
+
+Вложения — часть агрегата `Comment` (`fileIds`). Отдельных эндпоинтов нет:
+
+```
+POST  /api/issues/:issueId/comments  { "content": "...", "fileIds": ["…"] }
+PATCH /api/comments/:id              { "content": "...", "fileIds": [...] }
+```
+
+- **Ответы.** `CommentDto.attachments: FileDto[]` — в create, update, списке
+  и SSE-событиях.
+- **Правка.** `fileIds` при update задаёт набор целиком; не передан — вложения
+  не меняются.
+  - Синхронизация связей идёт в одной транзакции с правкой текста.
+  - Изменение только набора файлов тоже считается правкой
+    (`editedAt`, `comment.updated`).
+  - Проверяются только добавленные файлы.
+- **Ограничения:** максимум `Comment.MAX_ATTACHMENTS = 10`, дубли убираются.
+- **Порядок** — по времени загрузки. id файлов — uuid v7, поэтому
+  сортировка по строке совпадает с порядком загрузки.
+- **Мягкое удаление** комментария снимает связи, файлы забирает GC. В ответе
+  у удалённого комментария `attachments: []`.
+- `CommentAttachmentFileOwnerService` регистрируется в реестре. Файл виден
+  тем, кому видна задача неудалённого комментария с этим файлом.
+- `CommentAuthorExpanderService` переименован в `CommentExpanderService`:
+  он раскрывает и авторов, и файлы (параллельно).
+
+## Прочие изменения
+
+- **Зависимости:** `@aws-sdk/client-s3`, `file-type`, `@nestjs/schedule`;
+  dev — `@types/multer`.
+- **`tsconfig.json`:** `multer` добавлен в `types`, иначе не виден
+  `Express.Multer.File`.
+- **`.gitignore` / `.dockerignore`:** добавлен `/storage` — каталог
+  локального хранилища.
+
+## Переменные окружения
+
+```
+FILE_STORAGE=s3                # local (по умолчанию) | s3
+FILE_STORAGE_LOCAL_DIR=./storage
+FILE_MAX_SIZE_MB=25
+FILE_ORPHAN_TTL_HOURS=24
+
+S3_ENDPOINT=http://rustfs:9000 # для AWS можно не задавать
+S3_REGION=us-east-1
+S3_BUCKET=ulitka
+S3_ACCESS_KEY_ID=...
+S3_SECRET_ACCESS_KEY=...
+S3_FORCE_PATH_STYLE=true       # для RustFS/MinIO
+```
+
+В `.env` были закомментированы `RUSTFS_*`. Адаптер использует общие `S3_*`.
+
+## Проверено
+
+- 154 unit-теста проходят. Типы, линтер и сборка чистые.
+- Приложение стартует, DI резолвится, новые маршруты без сессии отвечают 401.
+  В `schema.gql` появились `File`, `IssueAttachment`, `IssueDetail.attachments`.
+- **Не проверено:** сценарий целиком с авторизацией, реальной БД и S3
+  (upload → attach → download → GC).
+
+## TODO / открытые вопросы
+
+- [ ] Перед деплоем: создать бакет в RustFS (приложение его не создаёт),
+      прописать `FILE_STORAGE=s3` и `S3_*` на сервере.
+- [ ] Прогнать e2e: загрузка → прикрепление → скачивание другим участником →
+      открепление → GC.
+- [ ] Влить `feature/attachments` в `main`. Push в `main` запускает деплой —
+      сначала бакет и переменные окружения.
+- [ ] Лимит числа вложений у задачи (у комментария — 10).
+- [ ] SSE-события для вложений задачи (по образцу `CommentEventsService`).
+- [ ] Комментарий только с файлами, без текста? Сейчас текст обязателен.
+- [ ] Вложения комментариев в GraphQL — когда появятся комментарии в GraphQL.
+- [ ] GC при большом числе файлов: сейчас каждый запуск проходит по всем старым
+      файлам. При сотнях тысяч файлов — переписать на `NOT EXISTS`.
+- [ ] Маловероятная гонка: прикрепление файла, загруженного больше 24 ч назад,
+      ровно в момент прохода GC может его потерять.
+- [ ] Позже: отдавать скачивание redirect'ом на presigned GET вместо стрима
+      через Node.

package.json

@@ -24,44 +24,47 @@
   "dependencies": {
     "@apollo/server": "^5.5.1",
     "@as-integrations/express5": "^1.1.2",
-    "@better-auth/prisma-adapter": "^1.7.2",
+    "@aws-sdk/client-s3": "^3.1152.0",
+    "@better-auth/prisma-adapter": "^1.7.11",
     "@nestjs/apollo": "^14.0.0",
-    "@nestjs/common": "^12.0.1",
-    "@nestjs/config": "^12.0.0",
-    "@nestjs/core": "^12.0.1",
+    "@nestjs/common": "^12.2.0",
+    "@nestjs/config": "^12.0.1",
+    "@nestjs/core": "^12.2.0",
     "@nestjs/event-emitter": "^12.0.1",
     "@nestjs/graphql": "^14.0.0",
-    "@nestjs/platform-express": "^12.0.1",
-    "@nestjs/typeorm": "^12.0.1",
+    "@nestjs/platform-express": "^12.2.0",
+    "@nestjs/schedule": "^12.0.2",
     "@prisma/adapter-pg": "^7.10.0",
     "@prisma/client": "^7.10.0",
-    "@thallesp/nestjs-better-auth": "^2.7.0",
-    "better-auth": "^1.7.2",
+    "@thallesp/nestjs-better-auth": "^2.8.0",
+    "better-auth": "^1.7.11",
     "class-transformer": "^0.5.1",
     "class-validator": "^0.15.1",
+    "file-type": "^22.2.0",
+    "firebase-admin": "^14.5.0",
     "graphql": "^16.14.2",
-    "nodemailer": "^10.0.0",
+    "nodemailer": "^10.1.7",
     "pg": "^8.23.0",
     "reflect-metadata": "^0.2.2",
     "rxjs": "^7.8.1",
-    "typeorm": "^1.1.1",
-    "valibot": "^1.4.2"
+    "valibot": "^1.5.0"
   },
   "devDependencies": {
     "@nestjs/cli": "^12.0.0",
-    "@nestjs/mau": "^0.2.6",
+    "@nestjs/mau": "^0.2.8",
     "@nestjs/schematics": "^12.0.0",
-    "@nestjs/testing": "^12.0.1",
+    "@nestjs/testing": "^12.2.0",
     "@types/express": "^5.0.0",
+    "@types/multer": "^2.3.0",
     "@types/node": "^24.0.0",
     "@types/pg": "^8.23.1",
-    "@types/supertest": "^7.0.0",
+    "@types/supertest": "^7.2.1",
     "@vitest/coverage-v8": "^4.1.2",
-    "oxlint": "^1.58.0",
-    "prettier": "^3.4.2",
+    "oxlint": "^1.88.0",
+    "prettier": "^3.9.10",
     "prisma": "^7.10.0",
     "source-map-support": "^0.5.21",
-    "supertest": "^7.0.0",
+    "supertest": "^7.3.1",
     "typescript": "^6.0.2",
     "vite-tsconfig-paths": "^5.1.4",
     "vitest": "^4.1.2"

prisma/migrations/20261001081818_issue_users_set_null/migration.sql

@@ -0,0 +1,14 @@
+-- DropForeignKey
+ALTER TABLE "issue" DROP CONSTRAINT "issue_assigneeId_fkey";
+
+-- DropForeignKey
+ALTER TABLE "issue" DROP CONSTRAINT "issue_reporterId_fkey";
+
+-- AlterTable
+ALTER TABLE "issue" ALTER COLUMN "reporterId" DROP NOT NULL;
+
+-- AddForeignKey
+ALTER TABLE "issue" ADD CONSTRAINT "issue_assigneeId_fkey" FOREIGN KEY ("assigneeId") REFERENCES "user"("id") ON DELETE SET NULL ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "issue" ADD CONSTRAINT "issue_reporterId_fkey" FOREIGN KEY ("reporterId") REFERENCES "user"("id") ON DELETE SET NULL ON UPDATE CASCADE;

prisma/migrations/20261001081829_comment/migration.sql

@@ -0,0 +1,25 @@
+-- CreateTable
+CREATE TABLE "comment" (
+    "id" TEXT NOT NULL,
+    "content" TEXT NOT NULL,
+    "issueId" INTEGER NOT NULL,
+    "authorId" TEXT,
+    "editedAt" TIMESTAMPTZ(3),
+    "deletedAt" TIMESTAMPTZ(3),
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMPTZ(3) NOT NULL,
+
+    CONSTRAINT "comment_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE INDEX "comment_issueId_createdAt_idx" ON "comment"("issueId", "createdAt");
+
+-- CreateIndex
+CREATE INDEX "comment_authorId_idx" ON "comment"("authorId");
+
+-- AddForeignKey
+ALTER TABLE "comment" ADD CONSTRAINT "comment_issueId_fkey" FOREIGN KEY ("issueId") REFERENCES "issue"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "comment" ADD CONSTRAINT "comment_authorId_fkey" FOREIGN KEY ("authorId") REFERENCES "user"("id") ON DELETE SET NULL ON UPDATE CASCADE;

prisma/migrations/20261002045355_file/migration.sql

@@ -0,0 +1,25 @@
+-- CreateTable
+CREATE TABLE "file" (
+    "id" TEXT NOT NULL,
+    "storageKey" TEXT NOT NULL,
+    "fileName" TEXT NOT NULL,
+    "mimeType" TEXT NOT NULL,
+    "size" INTEGER NOT NULL,
+    "uploaderId" TEXT,
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "file_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE INDEX "file_uploaderId_idx" ON "file"("uploaderId");
+
+-- CreateIndex
+CREATE INDEX "file_createdAt_idx" ON "file"("createdAt");
+
+-- CreateIndex
+CREATE UNIQUE INDEX "file_storageKey_key" ON "file"("storageKey");
+
+-- AddForeignKey
+ALTER TABLE "file" ADD CONSTRAINT "file_uploaderId_fkey" FOREIGN KEY ("uploaderId") REFERENCES "user"("id") ON DELETE SET NULL ON UPDATE CASCADE;
+

prisma/migrations/20261002050156_issue_attachment/migration.sql

@@ -0,0 +1,18 @@
+-- CreateTable
+CREATE TABLE "issue_attachment" (
+    "issueId" INTEGER NOT NULL,
+    "fileId" TEXT NOT NULL,
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "issue_attachment_pkey" PRIMARY KEY ("issueId","fileId")
+);
+
+-- CreateIndex
+CREATE INDEX "issue_attachment_fileId_idx" ON "issue_attachment"("fileId");
+
+-- AddForeignKey
+ALTER TABLE "issue_attachment" ADD CONSTRAINT "issue_attachment_issueId_fkey" FOREIGN KEY ("issueId") REFERENCES "issue"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "issue_attachment" ADD CONSTRAINT "issue_attachment_fileId_fkey" FOREIGN KEY ("fileId") REFERENCES "file"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+

prisma/migrations/20261002060755_comment_attachment/migration.sql

@@ -0,0 +1,18 @@
+-- CreateTable
+CREATE TABLE "comment_attachment" (
+    "commentId" TEXT NOT NULL,
+    "fileId" TEXT NOT NULL,
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "comment_attachment_pkey" PRIMARY KEY ("commentId","fileId")
+);
+
+-- CreateIndex
+CREATE INDEX "comment_attachment_fileId_idx" ON "comment_attachment"("fileId");
+
+-- AddForeignKey
+ALTER TABLE "comment_attachment" ADD CONSTRAINT "comment_attachment_commentId_fkey" FOREIGN KEY ("commentId") REFERENCES "comment"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "comment_attachment" ADD CONSTRAINT "comment_attachment_fileId_fkey" FOREIGN KEY ("fileId") REFERENCES "file"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+

prisma/migrations/20261007120000_issue_change/migration.sql

@@ -0,0 +1,28 @@
+-- CreateTable
+CREATE TABLE "issue_change" (
+    "id" SERIAL NOT NULL,
+    "issueId" INTEGER NOT NULL,
+    "changeId" TEXT NOT NULL,
+    "field" TEXT NOT NULL,
+    "oldValue" TEXT,
+    "newValue" TEXT,
+    "actorId" TEXT,
+    "changedAt" TIMESTAMPTZ(3) NOT NULL,
+
+    CONSTRAINT "issue_change_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE INDEX "issue_change_issueId_changedAt_idx" ON "issue_change"("issueId", "changedAt");
+
+-- CreateIndex
+CREATE INDEX "issue_change_field_changedAt_idx" ON "issue_change"("field", "changedAt");
+
+-- CreateIndex
+CREATE INDEX "issue_change_actorId_idx" ON "issue_change"("actorId");
+
+-- AddForeignKey
+ALTER TABLE "issue_change" ADD CONSTRAINT "issue_change_issueId_fkey" FOREIGN KEY ("issueId") REFERENCES "issue"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "issue_change" ADD CONSTRAINT "issue_change_actorId_fkey" FOREIGN KEY ("actorId") REFERENCES "user"("id") ON DELETE SET NULL ON UPDATE CASCADE;

prisma/migrations/20261012120000_issue_project_due_date_index/migration.sql

@@ -0,0 +1,2 @@
+-- CreateIndex
+CREATE INDEX "issue_projectId_dueDate_idx" ON "issue"("projectId", "dueDate");

prisma/migrations/20261018173111_issue_type/migration.sql

@@ -0,0 +1,5 @@
+-- AlterTable
+ALTER TABLE "issue" ADD COLUMN     "type" TEXT NOT NULL DEFAULT 'TASK';
+
+-- CreateIndex
+CREATE INDEX "issue_projectId_type_idx" ON "issue"("projectId", "type");

prisma/migrations/20261023120000_user_avatar/migration.sql

@@ -0,0 +1,9 @@
+-- AlterTable
+ALTER TABLE "user" ADD COLUMN     "avatarFileId" TEXT;
+
+-- CreateIndex
+CREATE UNIQUE INDEX "user_avatarFileId_key" ON "user"("avatarFileId");
+
+-- AddForeignKey
+ALTER TABLE "user" ADD CONSTRAINT "user_avatarFileId_fkey" FOREIGN KEY ("avatarFileId") REFERENCES "file"("id") ON DELETE SET NULL ON UPDATE CASCADE;
+

prisma/migrations/20261025190802_issue_observer/migration.sql

@@ -0,0 +1,17 @@
+-- CreateTable
+CREATE TABLE "issue_observer" (
+    "issueId" INTEGER NOT NULL,
+    "userId" TEXT NOT NULL,
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "issue_observer_pkey" PRIMARY KEY ("issueId","userId")
+);
+
+-- CreateIndex
+CREATE INDEX "issue_observer_userId_idx" ON "issue_observer"("userId");
+
+-- AddForeignKey
+ALTER TABLE "issue_observer" ADD CONSTRAINT "issue_observer_issueId_fkey" FOREIGN KEY ("issueId") REFERENCES "issue"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "issue_observer" ADD CONSTRAINT "issue_observer_userId_fkey" FOREIGN KEY ("userId") REFERENCES "user"("id") ON DELETE CASCADE ON UPDATE CASCADE;

prisma/migrations/20261025192028_project_member_role/migration.sql

@@ -0,0 +1,5 @@
+-- CreateEnum
+CREATE TYPE "ProjectRole" AS ENUM ('MEMBER', 'OBSERVER');
+
+-- AlterTable
+ALTER TABLE "project_member" ADD COLUMN     "role" "ProjectRole" NOT NULL DEFAULT 'MEMBER';

prisma/migrations/20261028120000_tag/migration.sql

@@ -0,0 +1,37 @@
+-- CreateTable
+CREATE TABLE "tag" (
+    "id" TEXT NOT NULL,
+    "projectId" TEXT NOT NULL,
+    "name" TEXT NOT NULL,
+    "normalizedName" TEXT NOT NULL,
+    "color" TEXT NOT NULL DEFAULT 'default',
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMPTZ(3) NOT NULL,
+
+    CONSTRAINT "tag_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateTable
+CREATE TABLE "issue_tag" (
+    "issueId" INTEGER NOT NULL,
+    "tagId" TEXT NOT NULL,
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "issue_tag_pkey" PRIMARY KEY ("issueId","tagId")
+);
+
+-- CreateIndex
+CREATE UNIQUE INDEX "tag_projectId_normalizedName_key" ON "tag"("projectId", "normalizedName");
+
+-- CreateIndex
+CREATE INDEX "issue_tag_tagId_idx" ON "issue_tag"("tagId");
+
+-- AddForeignKey
+ALTER TABLE "tag" ADD CONSTRAINT "tag_projectId_fkey" FOREIGN KEY ("projectId") REFERENCES "project"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "issue_tag" ADD CONSTRAINT "issue_tag_issueId_fkey" FOREIGN KEY ("issueId") REFERENCES "issue"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "issue_tag" ADD CONSTRAINT "issue_tag_tagId_fkey" FOREIGN KEY ("tagId") REFERENCES "tag"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+

prisma/schema.prisma

@@ -13,6 +13,10 @@ model User {
   email                    String
   emailVerified            Boolean                   @default(false)
   image                    String?
+  /// Файл аватара; image хранит его URL для better-auth и клиента.
+  /// Меняется только через PUT /users/me/avatar — там проверяется, что файл свой.
+  avatarFileId             String?                   @unique
+  avatarFile               File?                     @relation(name: "userAvatar", fields: [avatarFileId], references: [id], onDelete: SetNull)
   createdAt                DateTime                  @default(now())
   updatedAt                DateTime                  @updatedAt
   sessions                 Session[]
@@ -24,6 +28,10 @@ model User {
   notificationDeviceTokens NotificationDeviceToken[]
   notificationPreferences  NotificationPreference[]
   notificationMessages     NotificationMessage[]
+  comments                 Comment[]
+  uploadedFiles            File[]                    @relation(name: "fileUploader")
+  issueChanges             IssueChange[]
+  observedIssues           IssueObserver[]
 
   @@unique([email])
   @@map("user")
@@ -79,21 +87,27 @@ model Verification {
 }
 
 model Issue {
-  id         Int       @id @default(autoincrement())
-  key        String
-  title      String
-  content    String?
-  status     String
-  priority   Int       @default(0)
-  assigneeId String?
-  assignee   User?     @relation(name: "assigneeIssues", fields: [assigneeId], references: [id], onDelete: Cascade)
-  reporterId String
-  reporter   User      @relation(name: "reporterIssues", fields: [reporterId], references: [id], onDelete: Cascade)
-  projectId  String
-  project    Project   @relation(fields: [projectId], references: [id], onDelete: Cascade)
-  dueDate    DateTime? @db.Timestamptz(3)
-  createdAt  DateTime  @default(now()) @db.Timestamptz(3)
-  updatedAt  DateTime  @updatedAt @db.Timestamptz(3)
+  id          Int               @id @default(autoincrement())
+  key         String
+  title       String
+  content     String?
+  status      String
+  priority    Int               @default(0)
+  type        String            @default("TASK")
+  assigneeId  String?
+  assignee    User?             @relation(name: "assigneeIssues", fields: [assigneeId], references: [id], onDelete: SetNull)
+  reporterId  String?
+  reporter    User?             @relation(name: "reporterIssues", fields: [reporterId], references: [id], onDelete: SetNull)
+  projectId   String
+  project     Project           @relation(fields: [projectId], references: [id], onDelete: Cascade)
+  dueDate     DateTime?         @db.Timestamptz(3)
+  comments    Comment[]
+  attachments IssueAttachment[]
+  changes     IssueChange[]
+  observers   IssueObserver[]
+  tags        IssueTag[]
+  createdAt   DateTime          @default(now()) @db.Timestamptz(3)
+  updatedAt   DateTime          @updatedAt @db.Timestamptz(3)
 
   @@index([status])
   @@index([assigneeId])
@@ -102,9 +116,26 @@ model Issue {
   @@index([createdAt])
   @@index([projectId, createdAt])
   @@index([dueDate])
+  @@index([projectId, dueDate])
+  @@index([projectId, type])
   @@map("issue")
 }
 
+/// Наблюдатель задачи: видит её и может комментировать, но не редактировать.
+/// Редактируют задачу только reporter и assignee.
+model IssueObserver {
+  issueId   Int
+  userId    String
+  createdAt DateTime @default(now()) @db.Timestamptz(3)
+
+  issue Issue @relation(fields: [issueId], references: [id], onDelete: Cascade)
+  user  User  @relation(fields: [userId], references: [id], onDelete: Cascade)
+
+  @@id([issueId, userId])
+  @@index([userId])
+  @@map("issue_observer")
+}
+
 model Project {
   id        String          @id @default(uuid(7))
   name      String
@@ -115,6 +146,7 @@ model Project {
   ownerId   String
   owner     User            @relation(fields: [ownerId], references: [id], onDelete: Restrict)
   members   ProjectMember[]
+  tags      Tag[]
 
   @@unique([key])
   @@index([createdAt])
@@ -122,11 +154,51 @@ model Project {
   @@map("project")
 }
 
+/// Тег — элемент справочника проекта. Уникален в проекте без учёта регистра:
+/// normalizedName — name в нижнем регистре. color — из палитры (TAG_COLORS),
+/// валидируется в коде. Задаче тег назначают по имени — отсутствующий создаётся.
+model Tag {
+  id             String     @id @default(uuid(7))
+  projectId      String
+  project        Project    @relation(fields: [projectId], references: [id], onDelete: Cascade)
+  name           String
+  normalizedName String
+  color          String     @default("default")
+  issues         IssueTag[]
+  createdAt      DateTime   @default(now()) @db.Timestamptz(3)
+  updatedAt      DateTime   @updatedAt @db.Timestamptz(3)
+
+  @@unique([projectId, normalizedName])
+  @@map("tag")
+}
+
+/// Тег задачи. Удаление тега из справочника снимает его со всех задач (без записи в историю).
+model IssueTag {
+  issueId   Int
+  tagId     String
+  createdAt DateTime @default(now()) @db.Timestamptz(3)
+
+  issue Issue @relation(fields: [issueId], references: [id], onDelete: Cascade)
+  tag   Tag   @relation(fields: [tagId], references: [id], onDelete: Cascade)
+
+  @@id([issueId, tagId])
+  @@index([tagId])
+  @@map("issue_tag")
+}
+
+/// MEMBER создаёт задачи в проекте; OBSERVER только видит проект —
+/// он наблюдает за отдельными задачами (IssueObserver).
+enum ProjectRole {
+  MEMBER
+  OBSERVER
+}
+
 model ProjectMember {
-  id        String   @id @default(uuid(7))
+  id        String      @id @default(uuid(7))
   projectId String
   userId    String
-  createdAt DateTime @default(now()) @db.Timestamptz(3)
+  role      ProjectRole @default(MEMBER)
+  createdAt DateTime    @default(now()) @db.Timestamptz(3)
 
   project Project @relation(fields: [projectId], references: [id], onDelete: Cascade)
   user    User    @relation(fields: [userId], references: [id], onDelete: Cascade)
@@ -188,3 +260,104 @@ model NotificationMessage {
   @@index([createdAt])
   @@map("notification_message")
 }
+
+/// Комментарий к задаче. При удалении автора комментарий остаётся (authorId -> NULL).
+/// deletedAt — мягкое удаление, editedAt — время последней правки текста.
+model Comment {
+  id          String              @id @default(uuid(7))
+  content     String
+  issueId     Int
+  issue       Issue               @relation(fields: [issueId], references: [id], onDelete: Cascade)
+  authorId    String?
+  author      User?               @relation(fields: [authorId], references: [id], onDelete: SetNull)
+  editedAt    DateTime?           @db.Timestamptz(3)
+  deletedAt   DateTime?           @db.Timestamptz(3)
+  createdAt   DateTime            @default(now()) @db.Timestamptz(3)
+  updatedAt   DateTime            @updatedAt @db.Timestamptz(3)
+  attachments CommentAttachment[]
+
+  @@index([issueId, createdAt])
+  @@index([authorId])
+  @@map("comment")
+}
+
+/// Загруженный файл. Ничего не знает о владельце: к задачам, комментариям и т.п.
+/// файлы привязываются через таблицы связей в модулях-владельцах.
+/// Файл, на который никто не ссылается, считается сиротой и удаляется GC.
+/// storageKey — ключ объекта в хранилище, имя от пользователя в него не попадает.
+model File {
+  id         String   @id @default(uuid(7))
+  storageKey String
+  fileName   String
+  mimeType   String
+  size       Int
+  uploaderId String?
+  uploader   User?    @relation(name: "fileUploader", fields: [uploaderId], references: [id], onDelete: SetNull)
+  createdAt  DateTime @default(now()) @db.Timestamptz(3)
+
+  issueAttachments   IssueAttachment[]
+  commentAttachments CommentAttachment[]
+  avatarOf           User?             @relation(name: "userAvatar")
+
+  @@unique([storageKey])
+  @@index([uploaderId])
+  @@index([createdAt])
+  @@map("file")
+}
+
+/// Вложение задачи — связь задачи с файлом. Удаление задачи или файла
+/// удаляет связь каскадом; сам файл, оставшийся без связей, удалит GC.
+model IssueAttachment {
+  issueId   Int
+  issue     Issue    @relation(fields: [issueId], references: [id], onDelete: Cascade)
+  fileId    String
+  file      File     @relation(fields: [fileId], references: [id], onDelete: Cascade)
+  createdAt DateTime @default(now()) @db.Timestamptz(3)
+
+  @@id([issueId, fileId])
+  @@index([fileId])
+  @@map("issue_attachment")
+}
+
+/// Вложение комментария — связь комментария с файлом. Управляется вместе
+/// с комментарием (fileIds в create/update); при мягком удалении комментария
+/// связи снимаются, чтобы файлы забрал GC.
+model CommentAttachment {
+  commentId String
+  comment   Comment  @relation(fields: [commentId], references: [id], onDelete: Cascade)
+  fileId    String
+  file      File     @relation(fields: [fileId], references: [id], onDelete: Cascade)
+  createdAt DateTime @default(now()) @db.Timestamptz(3)
+
+  @@id([commentId, fileId])
+  @@index([fileId])
+  @@map("comment_attachment")
+}
+
+/// История изменений задачи — одна строка на изменённое поле.
+/// Строки одного сохранения задачи объединены общим changeId.
+/// field: created | title | content | status | priority | type | assignee | dueDate | observer | tag
+/// (валидируется в коде, см. ISSUE_CHANGE_FIELDS). Значения — строки:
+/// priority — число, dueDate — ISO-дата, assignee — id пользователя.
+/// observer и tag — по строке на добавленный (oldValue = null) или снятый (newValue = null) элемент;
+/// observer — id пользователя, tag — имя тега на момент изменения.
+/// При создании задачи пишутся две строки: created и status null -> OPEN,
+/// поэтому статус задачи на любой момент восстанавливается по строкам status.
+/// У задач, созданных до появления истории, строк нет — в статистику они не попадают.
+model IssueChange {
+  id        Int      @id @default(autoincrement())
+  issueId   Int
+  issue     Issue    @relation(fields: [issueId], references: [id], onDelete: Cascade)
+  changeId  String
+  field     String
+  oldValue  String?
+  newValue  String?
+  actorId   String?
+  actor     User?    @relation(fields: [actorId], references: [id], onDelete: SetNull)
+  changedAt DateTime @db.Timestamptz(3)
+
+  @@index([issueId, changedAt])
+  @@index([field, changedAt])
+  @@index([actorId])
+  @@map("issue_change")
+}

src/app.module.ts

@@ -5,11 +5,18 @@ import { IssueModule } from './modules/issue/issue.module.js';
 import { ProjectModule } from './modules/project/project.module.js';
 import { UserModule } from './modules/user/user.module.js';
 import { StatusModule } from './modules/status/status.module.js';
+import { IssueTypeModule } from './modules/issue-type/issue-type.module.js';
 import { NotificationModule } from './modules/notification/notification.module.js';
+import { CommentModule } from './modules/comment/comment.module.js';
+import { FileModule } from './modules/file/file.module.js';
+import { IssueAttachmentModule } from './modules/issue-attachment/issue-attachment.module.js';
+import { HistoryModule } from './modules/history/history.module.js';
+import { TagModule } from './modules/tag/tag.module.js';
 import { AuthModule } from '@thallesp/nestjs-better-auth';
 import { auth } from './lib/auth.js';
 import { ConfigModule } from '@nestjs/config';
 import { EventEmitterModule } from '@nestjs/event-emitter';
+import { ScheduleModule } from '@nestjs/schedule';
 import { GraphQLModule } from '@nestjs/graphql';
 import { ApolloDriver, type ApolloDriverConfig } from '@nestjs/apollo';
 import { join } from 'node:path';
@@ -20,19 +27,13 @@ import { join } from 'node:path';
       isGlobal: true,
       cache: true,
     }),
-    // Внутрипроцессная шина доменных событий. Notification-модуль слушает
-    // события через неё, не завязываясь на модули, которые их порождают.
     EventEmitterModule.forRoot(),
+    ScheduleModule.forRoot(),
     GraphQLModule.forRoot<ApolloDriverConfig>({
       driver: ApolloDriver,
       autoSchemaFile: join(process.cwd(), 'src/schema.gql'),
       sortSchema: true,
     }),
-    // TypeOrmModule.forRootAsync({
-    //   imports: [ConfigModule],
-    //   inject: [ConfigService],
-    //   useFactory: pgConfig,
-    // }),
     AuthModule.forRoot({
       auth: auth,
       bodyParser: {
@@ -45,7 +46,13 @@ import { join } from 'node:path';
     ProjectModule,
     UserModule,
     StatusModule,
+    IssueTypeModule,
     NotificationModule,
+    CommentModule,
+    FileModule,
+    IssueAttachmentModule,
+    HistoryModule,
+    TagModule,
   ],
   controllers: [AppController],
   providers: [AppService],

src/common/decorators/validators.ts

@@ -1,5 +1,5 @@
 import { Transform, TransformFnParams } from 'class-transformer';
-import { IsInt, IsNotEmpty, IsOptional, IsString, Max, MaxLength, Min } from 'class-validator';
+import { IsBoolean, IsInt, IsNotEmpty, IsOptional, IsString, Max, Min } from 'class-validator';
 import { applyDecorators } from '@nestjs/common';
 
 interface ToStringOptions {
@@ -11,6 +11,7 @@ interface BaseDecoratorParams {
 }
 
 export interface StringDecoratorParams extends BaseDecoratorParams {}
+export interface BooleanDecoratorParams extends BaseDecoratorParams {}
 export interface IntDecoratorParams extends BaseDecoratorParams {
   min?: number;
   max?: number;
@@ -24,6 +25,15 @@ const ToNumber = () =>
     return Number.isNaN(parsed) ? undefined : parsed;
   });
 
+/** Query-параметры приходят строками: 'true'/'false' → boolean, остальное оставляем как есть для IsBoolean */
+const ToBoolean = () =>
+  Transform(({ value }) => {
+    if (value === undefined || value === null || value === '') return undefined;
+    if (value === 'true') return true;
+    if (value === 'false') return false;
+    return value;
+  });
+
 const ToString = (options?: ToStringOptions) =>
   Transform(({ value }: TransformFnParams) => {
     if (value === undefined || value === null) return undefined;
@@ -52,3 +62,11 @@ export function IntDecorator(params?: IntDecoratorParams) {
 
   return applyDecorators(...args);
 }
+
+export function BooleanDecorator(params?: BooleanDecoratorParams) {
+  const args = [IsBoolean(), ToBoolean()];
+
+  if (params?.isOptional) args.push(IsOptional());
+
+  return applyDecorators(...args);
+}

src/common/interceptors/transform-response.interceptor.ts

@@ -1,6 +1,7 @@
-import { CallHandler, ExecutionContext, Injectable, NestInterceptor } from '@nestjs/common';
+import { CallHandler, ExecutionContext, Injectable, NestInterceptor, StreamableFile } from '@nestjs/common';
 import { Observable } from 'rxjs';
 import { map } from 'rxjs/operators';
+import { SSE_METADATA } from '@nestjs/common/constants.js';
 import { PaginationMeta } from '../interfaces/pagination-meta.interface.js';
 
 export interface ResponseEnvelope<T> {
@@ -30,18 +31,26 @@ export class TransformResponseInterceptor<T> implements NestInterceptor<
     context: ExecutionContext,
     next: CallHandler<T>,
   ): Observable<T | ResponseEnvelope<T> | PaginatedResponseEnvelope<T>> {
-    // GraphQL уже оборачивает ответ в {data, errors} на уровне транспорта —
-    // конверт применяем только к HTTP (REST) контексту, чтобы не задваивать его.
     if (context.getType() !== 'http') {
       return next.handle();
     }
 
+    // SSE-обработчик возвращает поток MessageEvent ({type, data, id}) — его
+    // сериализует сам Nest. Обёртка в {data, code} спрятала бы type внутрь data,
+    // и клиентский addEventListener('<type>') перестал бы срабатывать.
+    if (Reflect.getMetadata(SSE_METADATA, context.getHandler())) {
+      return next.handle();
+    }
+
     const response = context.switchToHttp().getResponse();
 
     return next.handle().pipe(
       map((result) => {
-        // Пагинированные ответы ({data, meta}) разворачиваем на верхний
-        // уровень конверта, а не оборачиваем повторно как data.data.
+        // Файл отдаётся потоком как есть — обёртка {data, code} сломала бы скачивание
+        if (result instanceof StreamableFile) {
+          return result;
+        }
+
         if (isPaginatedResult<T>(result)) {
           return {
             data: result.data ?? null,

src/configs/db.config.ts

@@ -1,7 +1,6 @@
 import { ConfigService } from '@nestjs/config';
-import { TypeOrmModuleOptions } from '@nestjs/typeorm';
 
-export function pgConfig(config: ConfigService): TypeOrmModuleOptions {
+export function pgConfig(config: ConfigService): unknown {
   return {
     type: 'postgres',
     url: config.getOrThrow<string>('DATABASE_URL'),

src/lib/auth.ts

@@ -2,12 +2,35 @@ import { betterAuth } from 'better-auth';
 import { prismaAdapter } from '@better-auth/prisma-adapter';
 import prisma from './prisma.js';
 import EmailSender from './email-sender.js';
+import { emailOTP } from 'better-auth/plugins';
 
 export const auth = betterAuth({
   appName: process.env.APP_NAME ?? 'app',
   basePath: '/api/auth',
   plugins: [
     // authTransformResponse()
+    emailOTP({
+      async sendVerificationOTP({ email, otp, type }) {
+        if (type === 'sign-in') {
+          EmailSender.sendInBackground({
+            to: email,
+            subject: `Your OTP code is: ${otp}`,
+            text: `Your OTP code is: ${otp}`,
+          });
+        } else if (type === 'email-verification') {
+          // Send the OTP for email verification
+          console.log({ email, otp, type });
+        } else if (type === 'forget-password') {
+          EmailSender.sendInBackground({
+            to: email,
+            subject: `Your password reset code is: ${otp}`,
+            text: `Your password reset code is: ${otp}`,
+          });
+        } else {
+          console.log({ email, otp, type });
+        }
+      },
+    }),
   ],
   database: prismaAdapter(prisma, {
     provider: 'postgresql',
@@ -24,28 +47,23 @@ export const auth = betterAuth({
   emailAndPassword: {
     enabled: true,
     autoSignIn: false,
-    requireEmailVerification: false,
+    requireEmailVerification: true,
     onExistingUserSignUp: async ({ user }, request) => {
-      console.log('onExistingUserSignUp', { user });
-
-      void EmailSender.getTransporter().sendMail({
+      EmailSender.sendInBackground({
         to: user.email,
         subject: 'Sign-up attempt with your email',
         text: 'Someone tried to create an account using your email address. If this was you, try signing in instead. If not, you can safely ignore this email.',
       });
     },
     sendResetPassword: async ({ user, url, token }, request) => {
-      console.log('sendResetPassword', { user, url, token });
-      void EmailSender.getTransporter().sendMail({
+      EmailSender.sendInBackground({
         to: user.email,
         subject: 'Reset your password',
         text: `Click the link to reset your password: ${url}`,
       });
     },
     onPasswordReset: async ({ user }, request) => {
-      // your logic here
-      console.log('onPasswordReset', { user });
-      void EmailSender.getTransporter().sendMail({
+      EmailSender.sendInBackground({
         to: user.email,
         subject: 'Reset your password result',
         text: `Password for user ${user.email} has been reset.`,
@@ -56,8 +74,7 @@ export const auth = betterAuth({
     sendOnSignIn: true,
     autoSignInAfterVerification: true,
     sendVerificationEmail: async ({ user, url }) => {
-      console.log('emailVerification', { user, url });
-      void EmailSender.getTransporter().sendMail({
+      EmailSender.sendInBackground({
         to: user.email,
         subject: 'Verify your email address',
         text: `Click the link to verify your email: ${url}`,

src/lib/email-sender.ts

@@ -1,13 +1,44 @@
+import { Logger } from '@nestjs/common';
 import nodemailer, { SendMailOptions, Transporter } from 'nodemailer';
 
 export default class EmailSender {
-  static getTransporter() {
-    return nodemailer.createTransport({
+  private static readonly logger = new Logger(EmailSender.name);
+  private static transporter?: Transporter;
+
+  private static isLocal() {
+    return process.env.NODE_ENV === 'local';
+  }
+
+  private static getTransporter() {
+    this.transporter ??= nodemailer.createTransport({
       service: 'gmail',
       auth: {
         user: process.env.GOOGLE_APP_USER,
         pass: process.env.GOOGLE_APP_PASSWORD,
       },
     });
+    return this.transporter;
+  }
+
+  /** Sends an email; throws on failure. In local env only logs the message. */
+  static async send(options: SendMailOptions): Promise<void> {
+    if (this.isLocal()) {
+      this.logger.log(
+        `[local] email not sent\n  to: ${String(options.to)}\n  subject: ${options.subject}\n  text: ${String(options.text)}`,
+      );
+      return;
+    }
+
+    await this.getTransporter().sendMail(options);
+  }
+
+  /** Fire-and-forget variant: never throws, errors are logged. */
+  static sendInBackground(options: SendMailOptions): void {
+    this.send(options).catch((error: unknown) => {
+      this.logger.error(
+        `Failed to send email "${options.subject}" to ${String(options.to)}`,
+        error instanceof Error ? error.stack : String(error),
+      );
+    });
   }
 }

src/main.ts

@@ -16,12 +16,7 @@ async function bootstrap() {
     logger: new CustomLogger(),
   });
 
-  // app.useGlobalPipes(new StandardSchemaValidationPipe());
-
   app.setGlobalPrefix('api');
-
-  // Глобальный body-parser отключён (better-auth сам парсит своё тело),
-  // поэтому для GraphQL включаем JSON-парсинг точечно на его пути.
   app.use('/graphql', json());
   app.useGlobalPipes(new ValidationPipe({ whitelist: true, transform: true }));
   app.useGlobalInterceptors(new TransformResponseInterceptor());

src/modules/comment/application/dto/comment.dto.ts

@@ -0,0 +1,18 @@
+import { UserDto } from '../../../user/application/dto/user.dto.js';
+import { FileDto } from '../../../file/application/dto/file.dto.js';
+
+export class CommentDto {
+  id: string;
+  issueId: number;
+  authorId: string | null;
+  /** null — автор удалил аккаунт */
+  author: UserDto | null;
+  /** null у удалённого комментария — текст наружу не отдаём */
+  content: string | null;
+  /** Пусто у удалённого комментария. Скачивание — GET /files/:id/download */
+  attachments: FileDto[];
+  editedAt: Date | null;
+  deletedAt: Date | null;
+  createdAt: Date;
+  updatedAt: Date;
+}

src/modules/comment/application/mappers/comment-application.mapper.spec.ts

@@ -0,0 +1,74 @@
+import { describe, expect, it } from 'vitest';
+import { Comment } from '../../domain/entities/comment.entity.js';
+import { CommentApplicationMapper } from './comment-application.mapper.js';
+import { UserDto } from '../../../user/application/dto/user.dto.js';
+
+const author: UserDto = {
+  id: 'user-1',
+  name: 'User 1',
+  email: 'user-1@example.com',
+  emailVerified: true,
+  image: null,
+  createdAt: new Date('2026-01-01T00:00:00.000Z'),
+  updatedAt: new Date('2026-01-01T00:00:00.000Z'),
+};
+
+const buildComment = (deletedAt: Date | null = null, authorId: string | null = 'user-1', fileIds: string[] = []) =>
+  Comment.reconstitute({
+    id: 'comment-1',
+    content: 'Secret',
+    issueId: 1,
+    authorId,
+    fileIds,
+    editedAt: null,
+    deletedAt,
+    createdAt: new Date('2026-01-01T00:00:00.000Z'),
+    updatedAt: new Date('2026-01-01T00:00:00.000Z'),
+  });
+
+describe('CommentApplicationMapper', () => {
+  it('expands the author', () => {
+    const dto = CommentApplicationMapper.toDto(buildComment(), new Map([[author.id, author]]));
+
+    expect(dto.author).toEqual(author);
+    expect(dto.content).toBe('Secret');
+  });
+
+  it('hides content of a deleted comment', () => {
+    const dto = CommentApplicationMapper.toDto(buildComment(new Date()), new Map([[author.id, author]]));
+
+    expect(dto.content).toBeNull();
+    expect(dto.deletedAt).toBeInstanceOf(Date);
+  });
+
+  it('returns null author when the author account is deleted', () => {
+    const dto = CommentApplicationMapper.toDto(buildComment(null, null), new Map());
+
+    expect(dto.authorId).toBeNull();
+    expect(dto.author).toBeNull();
+  });
+
+  it('expands attachments and skips files that no longer exist', () => {
+    const file = {
+      id: 'file-1',
+      fileName: 'a.png',
+      mimeType: 'image/png',
+      size: 1,
+      uploaderId: 'user-1',
+      createdAt: new Date('2026-01-01T00:00:00.000Z'),
+    };
+    const dto = CommentApplicationMapper.toDto(
+      buildComment(null, 'user-1', ['file-1', 'gone']),
+      new Map(),
+      new Map([[file.id, file]]),
+    );
+
+    expect(dto.attachments).toEqual([file]);
+  });
+
+  it('hides attachments of a deleted comment', () => {
+    const dto = CommentApplicationMapper.toDto(buildComment(new Date(), 'user-1', ['file-1']), new Map(), new Map());
+
+    expect(dto.attachments).toEqual([]);
+  });
+});

src/modules/comment/application/mappers/comment-application.mapper.ts

@@ -0,0 +1,31 @@
+import { Comment } from '../../domain/entities/comment.entity.js';
+import { CommentDto } from '../dto/comment.dto.js';
+import { UserDto } from '../../../user/application/dto/user.dto.js';
+import { FileDto } from '../../../file/application/dto/file.dto.js';
+
+export class CommentApplicationMapper {
+  static toDto(
+    comment: Comment,
+    usersById: ReadonlyMap<string, UserDto>,
+    filesById: ReadonlyMap<string, FileDto> = new Map(),
+  ): CommentDto {
+    return {
+      id: comment.id as string,
+      issueId: comment.issueId,
+      authorId: comment.authorId,
+      author: comment.authorId ? (usersById.get(comment.authorId) ?? null) : null,
+      content: comment.isDeleted ? null : comment.content,
+      // Файл могли удалить между запросами — такое вложение просто не показываем
+      attachments: comment.isDeleted
+        ? []
+        : comment.fileIds.flatMap((fileId) => {
+            const file = filesById.get(fileId);
+            return file ? [file] : [];
+          }),
+      editedAt: comment.editedAt,
+      deletedAt: comment.deletedAt,
+      createdAt: comment.createdAt,
+      updatedAt: comment.updatedAt,
+    };
+  }
+}

src/modules/comment/application/services/comment-access.service.ts

@@ -0,0 +1,42 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { COMMENT_REPOSITORY, type ICommentRepository } from '../../domain/repositories/comment.repository.interface.js';
+import {
+  ISSUE_REPOSITORY,
+  type IIssueRepository,
+} from '../../../issue/domain/repositories/issue.repository.interface.js';
+import { Comment } from '../../domain/entities/comment.entity.js';
+import { CommentNotFoundException } from '../../domain/exceptions/comment-not-found.exception.js';
+
+@Injectable()
+export class CommentAccessService {
+  constructor(
+    @Inject(COMMENT_REPOSITORY)
+    private readonly commentRepository: ICommentRepository,
+    @Inject(ISSUE_REPOSITORY)
+    private readonly issueRepository: IIssueRepository,
+  ) {}
+
+  /** Видна ли задача пользователю (то же правило, что в IIssueRepository.findById) */
+  async isIssueVisible(issueId: number, userId: string): Promise<boolean> {
+    return (await this.issueRepository.findById(issueId, userId)) !== null;
+  }
+
+  /**
+   * Возвращает неудалённый комментарий, если его задача видна пользователю.
+   * Иначе — CommentNotFoundException, чтобы не раскрывать существование
+   * комментариев к чужим задачам.
+   */
+  async getVisibleComment(id: string, userId: string): Promise<Comment> {
+    const comment = await this.commentRepository.findById(id);
+    if (!comment || comment.isDeleted) {
+      throw new CommentNotFoundException(id);
+    }
+
+    const issue = await this.issueRepository.findById(comment.issueId, userId);
+    if (!issue) {
+      throw new CommentNotFoundException(id);
+    }
+
+    return comment;
+  }
+}

src/modules/comment/application/services/comment-attachment-file-owner.service.spec.ts

@@ -0,0 +1,40 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { ICommentRepository } from '../../domain/repositories/comment.repository.interface.js';
+import type { IIssueRepository } from '../../../issue/domain/repositories/issue.repository.interface.js';
+import { FileOwnerRegistry } from '../../../file/application/services/file-owner.registry.js';
+import { CommentAttachmentFileOwnerService } from './comment-attachment-file-owner.service.js';
+import { buildIssue, mockCommentRepository, mockIssueRepository } from '../use-cases/test-helpers.js';
+
+describe('CommentAttachmentFileOwnerService', () => {
+  let commentRepository: ICommentRepository;
+  let issueRepository: IIssueRepository;
+  let registry: FileOwnerRegistry;
+
+  beforeEach(() => {
+    commentRepository = mockCommentRepository();
+    issueRepository = mockIssueRepository();
+    registry = new FileOwnerRegistry();
+    new CommentAttachmentFileOwnerService(commentRepository, issueRepository, registry).onModuleInit();
+  });
+
+  it('registers itself, so GC keeps files attached to comments', async () => {
+    vi.mocked(commentRepository.findReferencedFileIds).mockResolvedValue(['a']);
+
+    expect(await registry.findReferenced(['a', 'b'])).toEqual(new Set(['a']));
+  });
+
+  it('makes a file visible to users who see the issue of its comment', async () => {
+    vi.mocked(commentRepository.findIssueIdsByAttachedFile).mockResolvedValue([1]);
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+
+    expect(await registry.isVisibleThroughAnyOwner('file-1', 'user-2')).toBe(true);
+    expect(issueRepository.findById).toHaveBeenCalledWith(1, 'user-2');
+  });
+
+  it('hides a file when the issue is not visible', async () => {
+    vi.mocked(commentRepository.findIssueIdsByAttachedFile).mockResolvedValue([1]);
+    vi.mocked(issueRepository.findById).mockResolvedValue(null);
+
+    expect(await registry.isVisibleThroughAnyOwner('file-1', 'user-3')).toBe(false);
+  });
+});

src/modules/comment/application/services/comment-attachment-file-owner.service.ts

@@ -0,0 +1,44 @@
+import { Inject, Injectable, type OnModuleInit } from '@nestjs/common';
+import { COMMENT_REPOSITORY, type ICommentRepository } from '../../domain/repositories/comment.repository.interface.js';
+import {
+  ISSUE_REPOSITORY,
+  type IIssueRepository,
+} from '../../../issue/domain/repositories/issue.repository.interface.js';
+import { FileOwnerRegistry, type FileOwner } from '../../../file/application/services/file-owner.registry.js';
+
+/**
+ * Регистрирует комментарии как владельца файлов: без этого GC file-модуля
+ * считал бы прикреплённые к комментариям файлы сиротами и удалял их.
+ */
+@Injectable()
+export class CommentAttachmentFileOwnerService implements FileOwner, OnModuleInit {
+  readonly name = 'comment';
+
+  constructor(
+    @Inject(COMMENT_REPOSITORY)
+    private readonly commentRepository: ICommentRepository,
+    @Inject(ISSUE_REPOSITORY)
+    private readonly issueRepository: IIssueRepository,
+    private readonly fileOwners: FileOwnerRegistry,
+  ) {}
+
+  onModuleInit(): void {
+    this.fileOwners.register(this);
+  }
+
+  findReferenced(fileIds: string[]): Promise<string[]> {
+    return this.commentRepository.findReferencedFileIds(fileIds);
+  }
+
+  /** Файл виден, если видна задача хоть одного неудалённого комментария с ним */
+  async isVisibleThrough(fileId: string, userId: string): Promise<boolean> {
+    const issueIds = await this.commentRepository.findIssueIdsByAttachedFile(fileId);
+
+    for (const issueId of issueIds) {
+      if (await this.issueRepository.findById(issueId, userId)) {
+        return true;
+      }
+    }
+    return false;
+  }
+}

src/modules/comment/application/services/comment-events.service.ts

@@ -0,0 +1,28 @@
+import { Injectable } from '@nestjs/common';
+import { Observable, Subject } from 'rxjs';
+import { CommentDto } from '../dto/comment.dto.js';
+
+export type CommentEventType = 'comment.created' | 'comment.updated' | 'comment.deleted';
+
+export interface CommentEvent {
+  type: CommentEventType;
+  comment: CommentDto;
+}
+
+/**
+ * In-process шина событий comment-модуля для SSE-подписчиков
+ * (по аналогии с IssueEventsService). Работает в пределах одного
+ * инстанса приложения — для нескольких инстансов понадобится Redis pub/sub.
+ */
+@Injectable()
+export class CommentEventsService {
+  private readonly events$ = new Subject<CommentEvent>();
+
+  emit(type: CommentEventType, comment: CommentDto): void {
+    this.events$.next({ type, comment });
+  }
+
+  onEvents(): Observable<CommentEvent> {
+    return this.events$.asObservable();
+  }
+}

src/modules/comment/application/services/comment-expander.service.ts

@@ -0,0 +1,38 @@
+import { Injectable } from '@nestjs/common';
+import { Comment } from '../../domain/entities/comment.entity.js';
+import { CommentDto } from '../dto/comment.dto.js';
+import { CommentApplicationMapper } from '../mappers/comment-application.mapper.js';
+import { GetUsersUseCase } from '../../../user/application/use-cases/get-users/get-users.use-case.js';
+import { GetUsersQuery } from '../../../user/application/use-cases/get-users/get-users.query.js';
+import { GetFilesUseCase } from '../../../file/application/use-cases/get-files/get-files.use-case.js';
+import { GetFilesQuery } from '../../../file/application/use-cases/get-files/get-files.query.js';
+
+/** Раскрывает автора и вложения комментария (или списка комментариев) */
+@Injectable()
+export class CommentExpanderService {
+  constructor(
+    private readonly getUsersUseCase: GetUsersUseCase,
+    private readonly getFilesUseCase: GetFilesUseCase,
+  ) {}
+
+  async expand(comment: Comment): Promise<CommentDto> {
+    const [dto] = await this.expandAll([comment]);
+    return dto!;
+  }
+
+  async expandAll(comments: Comment[]): Promise<CommentDto[]> {
+    if (comments.length === 0) return [];
+
+    const userIds = [...new Set(comments.map((comment) => comment.authorId).filter((id): id is string => Boolean(id)))];
+    const fileIds = comments.flatMap((comment) => comment.fileIds);
+
+    const [users, files] = await Promise.all([
+      userIds.length > 0 ? this.getUsersUseCase.execute(new GetUsersQuery(userIds)) : [],
+      fileIds.length > 0 ? this.getFilesUseCase.execute(new GetFilesQuery(fileIds)) : [],
+    ]);
+    const usersById = new Map(users.map((user) => [user.id, user]));
+    const filesById = new Map(files.map((file) => [file.id, file]));
+
+    return comments.map((comment) => CommentApplicationMapper.toDto(comment, usersById, filesById));
+  }
+}

src/modules/comment/application/use-cases/create-comment/create-comment.command.ts

@@ -0,0 +1,9 @@
+export class CreateCommentCommand {
+  constructor(
+    public readonly issueId: number,
+    public readonly authorId: string,
+    public readonly content: string,
+    /** Файлы, заранее загруженные автором через POST /files */
+    public readonly fileIds: string[] = [],
+  ) {}
+}

src/modules/comment/application/use-cases/create-comment/create-comment.use-case.spec.ts

@@ -0,0 +1,88 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { ICommentRepository } from '../../../domain/repositories/comment.repository.interface.js';
+import type { IIssueRepository } from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { Comment } from '../../../domain/entities/comment.entity.js';
+import { CommentEventsService } from '../../services/comment-events.service.js';
+import { CreateCommentUseCase } from './create-comment.use-case.js';
+import { CreateCommentCommand } from './create-comment.command.js';
+import { FileForbiddenException } from '../../../../file/domain/exceptions/file-forbidden.exception.js';
+import {
+  buildIssue,
+  mockCommentExpander,
+  mockCommentRepository,
+  mockFileAccess,
+  mockIssueRepository,
+} from '../test-helpers.js';
+
+describe('CreateCommentUseCase', () => {
+  let commentRepository: ICommentRepository;
+  let issueRepository: IIssueRepository;
+  let commentEventsService: CommentEventsService;
+  let useCase: CreateCommentUseCase;
+
+  beforeEach(() => {
+    commentRepository = mockCommentRepository();
+    issueRepository = mockIssueRepository();
+    commentEventsService = new CommentEventsService();
+    useCase = new CreateCommentUseCase(
+      commentRepository,
+      issueRepository,
+      mockCommentExpander(),
+      commentEventsService,
+      mockFileAccess({ foreign: new FileForbiddenException('foreign') }),
+    );
+
+    vi.mocked(commentRepository.create).mockImplementation(async (comment: Comment) =>
+      Comment.reconstitute({
+        id: 'comment-1',
+        content: comment.content,
+        issueId: comment.issueId,
+        authorId: comment.authorId,
+        fileIds: [...comment.fileIds],
+        editedAt: null,
+        deletedAt: null,
+        createdAt: comment.createdAt,
+        updatedAt: comment.updatedAt,
+      }),
+    );
+  });
+
+  it('creates a comment on a visible issue and emits comment.created', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+    const received: unknown[] = [];
+    commentEventsService.onEvents().subscribe((event) => received.push(event));
+
+    const dto = await useCase.execute(new CreateCommentCommand(1, 'user-1', 'Hello'));
+
+    expect(issueRepository.findById).toHaveBeenCalledWith(1, 'user-1');
+    expect(dto).toMatchObject({ id: 'comment-1', issueId: 1, authorId: 'user-1', content: 'Hello' });
+    expect(received).toEqual([{ type: 'comment.created', comment: dto }]);
+  });
+
+  it('throws IssueNotFoundException when the issue is not visible to the user', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(null);
+
+    await expect(useCase.execute(new CreateCommentCommand(1, 'user-2', 'Hello'))).rejects.toThrow(
+      IssueNotFoundException,
+    );
+    expect(commentRepository.create).not.toHaveBeenCalled();
+  });
+
+  it('saves own files as attachments', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+
+    await useCase.execute(new CreateCommentCommand(1, 'user-1', 'Hello', ['b', 'a', 'b']));
+
+    expect(vi.mocked(commentRepository.create).mock.calls[0]![0].fileIds).toEqual(['a', 'b']);
+  });
+
+  it('does not create the comment when a file is not attachable', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+
+    await expect(useCase.execute(new CreateCommentCommand(1, 'user-1', 'Hello', ['a', 'foreign']))).rejects.toThrow(
+      FileForbiddenException,
+    );
+    expect(commentRepository.create).not.toHaveBeenCalled();
+  });
+});

src/modules/comment/application/use-cases/create-comment/create-comment.use-case.ts

@@ -0,0 +1,56 @@
+import { Inject, Injectable } from '@nestjs/common';
+import {
+  COMMENT_REPOSITORY,
+  type ICommentRepository,
+} from '../../../domain/repositories/comment.repository.interface.js';
+import {
+  ISSUE_REPOSITORY,
+  type IIssueRepository,
+} from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { Comment } from '../../../domain/entities/comment.entity.js';
+import { CreateCommentCommand } from './create-comment.command.js';
+import { CommentDto } from '../../dto/comment.dto.js';
+import { CommentExpanderService } from '../../services/comment-expander.service.js';
+import { CommentEventsService } from '../../services/comment-events.service.js';
+import { FileAccessService } from '../../../../file/application/services/file-access.service.js';
+
+@Injectable()
+export class CreateCommentUseCase {
+  constructor(
+    @Inject(COMMENT_REPOSITORY)
+    private readonly commentRepository: ICommentRepository,
+    @Inject(ISSUE_REPOSITORY)
+    private readonly issueRepository: IIssueRepository,
+    private readonly commentExpander: CommentExpanderService,
+    private readonly commentEventsService: CommentEventsService,
+    private readonly fileAccess: FileAccessService,
+  ) {}
+
+  async execute(command: CreateCommentCommand): Promise<CommentDto> {
+    // Комментировать можно только видимую пользователю задачу
+    const issue = await this.issueRepository.findById(command.issueId, command.authorId);
+    if (!issue) {
+      throw new IssueNotFoundException(command.issueId);
+    }
+
+    const comment = Comment.create({
+      issueId: command.issueId,
+      authorId: command.authorId,
+      content: command.content,
+      fileIds: command.fileIds,
+    });
+
+    // Прикреплять можно только свои файлы (см. FileAccessService.getAttachableFile)
+    for (const fileId of comment.fileIds) {
+      await this.fileAccess.getAttachableFile(fileId, command.authorId);
+    }
+
+    const saved = await this.commentRepository.create(comment);
+    const dto = await this.commentExpander.expand(saved);
+
+    this.commentEventsService.emit('comment.created', dto);
+
+    return dto;
+  }
+}

src/modules/comment/application/use-cases/delete-comment/delete-comment.command.ts

@@ -0,0 +1,6 @@
+export class DeleteCommentCommand {
+  constructor(
+    public readonly id: string,
+    public readonly userId: string,
+  ) {}
+}

src/modules/comment/application/use-cases/delete-comment/delete-comment.use-case.spec.ts

@@ -0,0 +1,78 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { ICommentRepository } from '../../../domain/repositories/comment.repository.interface.js';
+import type { IIssueRepository } from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { Comment } from '../../../domain/entities/comment.entity.js';
+import { CommentNotFoundException } from '../../../domain/exceptions/comment-not-found.exception.js';
+import { CommentForbiddenException } from '../../../domain/exceptions/comment-forbidden.exception.js';
+import { CommentEventsService, type CommentEvent } from '../../services/comment-events.service.js';
+import { CommentAccessService } from '../../services/comment-access.service.js';
+import { DeleteCommentUseCase } from './delete-comment.use-case.js';
+import { DeleteCommentCommand } from './delete-comment.command.js';
+import {
+  buildComment,
+  buildIssue,
+  mockCommentExpander,
+  mockCommentRepository,
+  mockIssueRepository,
+} from '../test-helpers.js';
+
+describe('DeleteCommentUseCase', () => {
+  let commentRepository: ICommentRepository;
+  let issueRepository: IIssueRepository;
+  let commentEventsService: CommentEventsService;
+  let useCase: DeleteCommentUseCase;
+
+  beforeEach(() => {
+    commentRepository = mockCommentRepository();
+    issueRepository = mockIssueRepository();
+    commentEventsService = new CommentEventsService();
+    useCase = new DeleteCommentUseCase(
+      commentRepository,
+      new CommentAccessService(commentRepository, issueRepository),
+      mockCommentExpander(),
+      commentEventsService,
+    );
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+  });
+
+  it('soft-deletes the comment and emits comment.deleted without content', async () => {
+    vi.mocked(commentRepository.findById).mockResolvedValue(buildComment());
+    const received: CommentEvent[] = [];
+    commentEventsService.onEvents().subscribe((event) => received.push(event));
+
+    await useCase.execute(new DeleteCommentCommand('comment-1', 'user-1'));
+
+    const saved = vi.mocked(commentRepository.update).mock.calls[0]![0] as Comment;
+    expect(saved.isDeleted).toBe(true);
+    expect(received).toHaveLength(1);
+    expect(received[0]!.type).toBe('comment.deleted');
+    expect(received[0]!.comment.content).toBeNull();
+  });
+
+  it('drops attachments so GC can collect the files', async () => {
+    const comment = buildComment();
+    comment.edit('Original', 'user-1', ['file-1']);
+    vi.mocked(commentRepository.findById).mockResolvedValue(comment);
+
+    await useCase.execute(new DeleteCommentCommand('comment-1', 'user-1'));
+
+    expect(vi.mocked(commentRepository.update).mock.calls[0]![0].fileIds).toEqual([]);
+  });
+
+  it('throws CommentForbiddenException for a non-author', async () => {
+    vi.mocked(commentRepository.findById).mockResolvedValue(buildComment());
+
+    await expect(useCase.execute(new DeleteCommentCommand('comment-1', 'user-2'))).rejects.toThrow(
+      CommentForbiddenException,
+    );
+    expect(commentRepository.update).not.toHaveBeenCalled();
+  });
+
+  it('throws CommentNotFoundException when the comment does not exist', async () => {
+    vi.mocked(commentRepository.findById).mockResolvedValue(null);
+
+    await expect(useCase.execute(new DeleteCommentCommand('missing', 'user-1'))).rejects.toThrow(
+      CommentNotFoundException,
+    );
+  });
+});

src/modules/comment/application/use-cases/delete-comment/delete-comment.use-case.ts

@@ -0,0 +1,30 @@
+import { Inject, Injectable } from '@nestjs/common';
+import {
+  COMMENT_REPOSITORY,
+  type ICommentRepository,
+} from '../../../domain/repositories/comment.repository.interface.js';
+import { DeleteCommentCommand } from './delete-comment.command.js';
+import { CommentExpanderService } from '../../services/comment-expander.service.js';
+import { CommentEventsService } from '../../services/comment-events.service.js';
+import { CommentAccessService } from '../../services/comment-access.service.js';
+
+/** Мягкое удаление: проставляет deletedAt, запись остаётся в ленте */
+@Injectable()
+export class DeleteCommentUseCase {
+  constructor(
+    @Inject(COMMENT_REPOSITORY)
+    private readonly commentRepository: ICommentRepository,
+    private readonly commentAccess: CommentAccessService,
+    private readonly commentExpander: CommentExpanderService,
+    private readonly commentEventsService: CommentEventsService,
+  ) {}
+
+  async execute(command: DeleteCommentCommand): Promise<void> {
+    const comment = await this.commentAccess.getVisibleComment(command.id, command.userId);
+
+    comment.delete(command.userId);
+    await this.commentRepository.update(comment);
+
+    this.commentEventsService.emit('comment.deleted', await this.commentExpander.expand(comment));
+  }
+}

src/modules/comment/application/use-cases/list-comments/list-comments.query.ts

@@ -0,0 +1,11 @@
+import type { CommentListDirection } from '../../../domain/repositories/comment.repository.interface.js';
+
+export class ListCommentsQuery {
+  constructor(
+    public readonly issueId: number,
+    public readonly userId: string,
+    public readonly limit: number,
+    public readonly cursor?: string,
+    public readonly direction: CommentListDirection = 'forward',
+  ) {}
+}

src/modules/comment/application/use-cases/list-comments/list-comments.use-case.spec.ts

@@ -0,0 +1,65 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { ICommentRepository } from '../../../domain/repositories/comment.repository.interface.js';
+import type { IIssueRepository } from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { ListCommentsUseCase } from './list-comments.use-case.js';
+import { ListCommentsQuery } from './list-comments.query.js';
+import {
+  buildComment,
+  buildIssue,
+  mockCommentExpander,
+  mockCommentRepository,
+  mockIssueRepository,
+} from '../test-helpers.js';
+
+describe('ListCommentsUseCase', () => {
+  let commentRepository: ICommentRepository;
+  let issueRepository: IIssueRepository;
+  let useCase: ListCommentsUseCase;
+
+  beforeEach(() => {
+    commentRepository = mockCommentRepository();
+    issueRepository = mockIssueRepository();
+    useCase = new ListCommentsUseCase(commentRepository, issueRepository, mockCommentExpander());
+  });
+
+  it('forwards pagination params and returns the next cursor', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+    vi.mocked(commentRepository.findByIssue).mockResolvedValue({
+      list: [buildComment({ id: 'comment-2' })],
+      nextCursor: 'comment-2',
+    });
+
+    const result = await useCase.execute(new ListCommentsQuery(1, 'user-1', 1, 'comment-1'));
+
+    expect(commentRepository.findByIssue).toHaveBeenCalledWith({
+      issueId: 1,
+      limit: 1,
+      cursor: 'comment-1',
+      direction: 'forward',
+    });
+    expect(result.list.map((comment) => comment.id)).toEqual(['comment-2']);
+    expect(result.nextCursor).toBe('comment-2');
+  });
+
+  it('forwards the backward direction for chat-style paging', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+    vi.mocked(commentRepository.findByIssue).mockResolvedValue({ list: [], nextCursor: null });
+
+    await useCase.execute(new ListCommentsQuery(1, 'user-1', 20, 'comment-5', 'backward'));
+
+    expect(commentRepository.findByIssue).toHaveBeenCalledWith({
+      issueId: 1,
+      limit: 20,
+      cursor: 'comment-5',
+      direction: 'backward',
+    });
+  });
+
+  it('throws IssueNotFoundException when the issue is not visible to the user', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(null);
+
+    await expect(useCase.execute(new ListCommentsQuery(1, 'user-2', 50))).rejects.toThrow(IssueNotFoundException);
+    expect(commentRepository.findByIssue).not.toHaveBeenCalled();
+  });
+});

src/modules/comment/application/use-cases/list-comments/list-comments.use-case.ts

@@ -0,0 +1,40 @@
+import { Inject, Injectable } from '@nestjs/common';
+import {
+  COMMENT_REPOSITORY,
+  type ICommentRepository,
+} from '../../../domain/repositories/comment.repository.interface.js';
+import {
+  ISSUE_REPOSITORY,
+  type IIssueRepository,
+} from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { ListCommentsQuery } from './list-comments.query.js';
+import { CommentDto } from '../../dto/comment.dto.js';
+import { CommentExpanderService } from '../../services/comment-expander.service.js';
+
+@Injectable()
+export class ListCommentsUseCase {
+  constructor(
+    @Inject(COMMENT_REPOSITORY)
+    private readonly commentRepository: ICommentRepository,
+    @Inject(ISSUE_REPOSITORY)
+    private readonly issueRepository: IIssueRepository,
+    private readonly commentExpander: CommentExpanderService,
+  ) {}
+
+  async execute(query: ListCommentsQuery): Promise<{ list: CommentDto[]; nextCursor: string | null }> {
+    const issue = await this.issueRepository.findById(query.issueId, query.userId);
+    if (!issue) {
+      throw new IssueNotFoundException(query.issueId);
+    }
+
+    const { list, nextCursor } = await this.commentRepository.findByIssue({
+      issueId: query.issueId,
+      limit: query.limit,
+      cursor: query.cursor,
+      direction: query.direction,
+    });
+
+    return { list: await this.commentExpander.expandAll(list), nextCursor };
+  }
+}

src/modules/comment/application/use-cases/test-helpers.ts

@@ -0,0 +1,77 @@
+import { vi } from 'vitest';
+import type { ICommentRepository } from '../../domain/repositories/comment.repository.interface.js';
+import type { IIssueRepository } from '../../../issue/domain/repositories/issue.repository.interface.js';
+import { Comment } from '../../domain/entities/comment.entity.js';
+import { Issue } from '../../../issue/domain/entities/issue.entity.js';
+import { CommentExpanderService } from '../services/comment-expander.service.js';
+import { CommentApplicationMapper } from '../mappers/comment-application.mapper.js';
+import type { FileAccessService } from '../../../file/application/services/file-access.service.js';
+
+export const buildComment = (
+  overrides: Partial<{ id: string; issueId: number; authorId: string; deletedAt: Date | null }> = {},
+) =>
+  Comment.reconstitute({
+    id: overrides.id ?? 'comment-1',
+    content: 'Original',
+    issueId: overrides.issueId ?? 1,
+    authorId: overrides.authorId ?? 'user-1',
+    editedAt: null,
+    deletedAt: overrides.deletedAt ?? null,
+    createdAt: new Date('2026-01-01T00:00:00.000Z'),
+    updatedAt: new Date('2026-01-01T00:00:00.000Z'),
+  });
+
+export const buildIssue = () =>
+  Issue.reconstitute({
+    id: 1,
+    key: 'ISSUE-1',
+    title: 'Issue',
+    content: null,
+    status: 'OPEN',
+    priority: 0,
+    type: 'TASK',
+    assignee: null,
+    reporter: 'user-1',
+    projectId: 'project-1',
+    dueDate: null,
+    createdAt: new Date('2026-01-01T00:00:00.000Z'),
+    updatedAt: new Date('2026-01-01T00:00:00.000Z'),
+  });
+
+export const mockCommentRepository = (): ICommentRepository => ({
+  findById: vi.fn(),
+  findByIssue: vi.fn(),
+  create: vi.fn(),
+  update: vi.fn(),
+  findIssueIdsByAttachedFile: vi.fn(),
+  findReferencedFileIds: vi.fn(),
+});
+
+export const mockIssueRepository = (): IIssueRepository => ({
+  findById: vi.fn(),
+  findByCKey: vi.fn(),
+  findAll: vi.fn(),
+  findByDueDateRange: vi.fn(),
+  countByStatus: vi.fn(),
+  create: vi.fn(),
+  update: vi.fn(),
+  delete: vi.fn(),
+});
+
+/** Все файлы прикрепляемы, кроме перечисленных — для них бросается заданная ошибка */
+export const mockFileAccess = (rejections: Record<string, Error> = {}) =>
+  ({
+    getAttachableFile: vi.fn(async (fileId: string) => {
+      if (rejections[fileId]) throw rejections[fileId];
+      return { id: fileId };
+    }),
+  }) as unknown as FileAccessService;
+
+/** Экспандер без похода за пользователями и файлами: author всегда null, attachments пустые */
+export const mockCommentExpander = () => {
+  const toDto = (comment: Comment) => CommentApplicationMapper.toDto(comment, new Map());
+  return {
+    expand: vi.fn(async (comment: Comment) => toDto(comment)),
+    expandAll: vi.fn(async (comments: Comment[]) => comments.map(toDto)),
+  } as unknown as CommentExpanderService;
+};

src/modules/comment/application/use-cases/update-comment/update-comment.command.ts

@@ -0,0 +1,9 @@
+export class UpdateCommentCommand {
+  constructor(
+    public readonly id: string,
+    public readonly userId: string,
+    public readonly content: string,
+    /** Новый набор вложений целиком; undefined — не менять */
+    public readonly fileIds?: string[],
+  ) {}
+}

src/modules/comment/application/use-cases/update-comment/update-comment.use-case.spec.ts

@@ -0,0 +1,112 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { ICommentRepository } from '../../../domain/repositories/comment.repository.interface.js';
+import type { IIssueRepository } from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { CommentNotFoundException } from '../../../domain/exceptions/comment-not-found.exception.js';
+import { CommentForbiddenException } from '../../../domain/exceptions/comment-forbidden.exception.js';
+import { CommentEventsService } from '../../services/comment-events.service.js';
+import { CommentAccessService } from '../../services/comment-access.service.js';
+import { UpdateCommentUseCase } from './update-comment.use-case.js';
+import { UpdateCommentCommand } from './update-comment.command.js';
+import {
+  buildComment,
+  buildIssue,
+  mockCommentExpander,
+  mockCommentRepository,
+  mockFileAccess,
+  mockIssueRepository,
+} from '../test-helpers.js';
+import { FileNotFoundException } from '../../../../file/domain/exceptions/file-not-found.exception.js';
+import type { FileAccessService } from '../../../../file/application/services/file-access.service.js';
+
+describe('UpdateCommentUseCase', () => {
+  let commentRepository: ICommentRepository;
+  let issueRepository: IIssueRepository;
+  let commentEventsService: CommentEventsService;
+  let useCase: UpdateCommentUseCase;
+  let received: unknown[];
+  let fileAccess: FileAccessService;
+
+  beforeEach(() => {
+    commentRepository = mockCommentRepository();
+    issueRepository = mockIssueRepository();
+    commentEventsService = new CommentEventsService();
+    fileAccess = mockFileAccess({ gone: new FileNotFoundException('gone') });
+    useCase = new UpdateCommentUseCase(
+      commentRepository,
+      new CommentAccessService(commentRepository, issueRepository),
+      mockCommentExpander(),
+      commentEventsService,
+      fileAccess,
+    );
+    received = [];
+    commentEventsService.onEvents().subscribe((event) => received.push(event));
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+  });
+
+  it('updates the content and emits comment.updated', async () => {
+    vi.mocked(commentRepository.findById).mockResolvedValue(buildComment());
+
+    const dto = await useCase.execute(new UpdateCommentCommand('comment-1', 'user-1', 'Changed'));
+
+    expect(dto.content).toBe('Changed');
+    expect(dto.editedAt).toBeInstanceOf(Date);
+    expect(commentRepository.update).toHaveBeenCalledTimes(1);
+    expect(received).toEqual([{ type: 'comment.updated', comment: dto }]);
+  });
+
+  it('skips saving and events when content did not change', async () => {
+    vi.mocked(commentRepository.findById).mockResolvedValue(buildComment());
+
+    await useCase.execute(new UpdateCommentCommand('comment-1', 'user-1', 'Original'));
+
+    expect(commentRepository.update).not.toHaveBeenCalled();
+    expect(received).toEqual([]);
+  });
+
+  it('throws CommentForbiddenException for a non-author', async () => {
+    vi.mocked(commentRepository.findById).mockResolvedValue(buildComment());
+
+    await expect(useCase.execute(new UpdateCommentCommand('comment-1', 'user-2', 'Changed'))).rejects.toThrow(
+      CommentForbiddenException,
+    );
+    expect(commentRepository.update).not.toHaveBeenCalled();
+  });
+
+  it('throws CommentNotFoundException for a deleted comment', async () => {
+    vi.mocked(commentRepository.findById).mockResolvedValue(buildComment({ deletedAt: new Date() }));
+
+    await expect(useCase.execute(new UpdateCommentCommand('comment-1', 'user-1', 'Changed'))).rejects.toThrow(
+      CommentNotFoundException,
+    );
+  });
+
+  it('throws CommentNotFoundException when the issue is not visible to the user', async () => {
+    vi.mocked(commentRepository.findById).mockResolvedValue(buildComment());
+    vi.mocked(issueRepository.findById).mockResolvedValue(null);
+
+    await expect(useCase.execute(new UpdateCommentCommand('comment-1', 'user-1', 'Changed'))).rejects.toThrow(
+      CommentNotFoundException,
+    );
+  });
+
+  it('replaces attachments, checking only newly added files', async () => {
+    const comment = buildComment();
+    comment.edit('Original', 'user-1', ['kept', 'removed']);
+    vi.mocked(commentRepository.findById).mockResolvedValue(comment);
+
+    await useCase.execute(new UpdateCommentCommand('comment-1', 'user-1', 'Original', ['kept', 'new']));
+
+    expect(fileAccess.getAttachableFile).toHaveBeenCalledExactlyOnceWith('new', 'user-1');
+    expect(vi.mocked(commentRepository.update).mock.calls[0]![0].fileIds).toEqual(['kept', 'new']);
+    expect(received).toHaveLength(1);
+  });
+
+  it('does not save when an added file is gone', async () => {
+    vi.mocked(commentRepository.findById).mockResolvedValue(buildComment());
+
+    await expect(
+      useCase.execute(new UpdateCommentCommand('comment-1', 'user-1', 'Original', ['gone'])),
+    ).rejects.toThrow(FileNotFoundException);
+    expect(commentRepository.update).not.toHaveBeenCalled();
+  });
+});

src/modules/comment/application/use-cases/update-comment/update-comment.use-case.ts

@@ -0,0 +1,49 @@
+import { Inject, Injectable } from '@nestjs/common';
+import {
+  COMMENT_REPOSITORY,
+  type ICommentRepository,
+} from '../../../domain/repositories/comment.repository.interface.js';
+import { UpdateCommentCommand } from './update-comment.command.js';
+import { CommentDto } from '../../dto/comment.dto.js';
+import { CommentExpanderService } from '../../services/comment-expander.service.js';
+import { CommentEventsService } from '../../services/comment-events.service.js';
+import { CommentAccessService } from '../../services/comment-access.service.js';
+import { FileAccessService } from '../../../../file/application/services/file-access.service.js';
+
+@Injectable()
+export class UpdateCommentUseCase {
+  constructor(
+    @Inject(COMMENT_REPOSITORY)
+    private readonly commentRepository: ICommentRepository,
+    private readonly commentAccess: CommentAccessService,
+    private readonly commentExpander: CommentExpanderService,
+    private readonly commentEventsService: CommentEventsService,
+    private readonly fileAccess: FileAccessService,
+  ) {}
+
+  async execute(command: UpdateCommentCommand): Promise<CommentDto> {
+    const comment = await this.commentAccess.getVisibleComment(command.id, command.userId);
+    const attachedBefore = new Set(comment.fileIds);
+
+    const changed = comment.edit(command.content, command.userId, command.fileIds);
+
+    // Проверяем только добавленные файлы: уже прикреплённые проверены при прикреплении
+    for (const fileId of comment.fileIds) {
+      if (!attachedBefore.has(fileId)) {
+        await this.fileAccess.getAttachableFile(fileId, command.userId);
+      }
+    }
+
+    if (changed) {
+      await this.commentRepository.update(comment);
+    }
+
+    const dto = await this.commentExpander.expand(comment);
+
+    if (changed) {
+      this.commentEventsService.emit('comment.updated', dto);
+    }
+
+    return dto;
+  }
+}

src/modules/comment/application/use-cases/watch-issue-comments/watch-issue-comments.query.ts

@@ -0,0 +1,6 @@
+export class WatchIssueCommentsQuery {
+  constructor(
+    public readonly issueId: number,
+    public readonly userId: string,
+  ) {}
+}

src/modules/comment/application/use-cases/watch-issue-comments/watch-issue-comments.use-case.spec.ts

@@ -0,0 +1,42 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { IIssueRepository } from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { CommentEventsService, type CommentEvent } from '../../services/comment-events.service.js';
+import { CommentApplicationMapper } from '../../mappers/comment-application.mapper.js';
+import { WatchIssueCommentsUseCase } from './watch-issue-comments.use-case.js';
+import { WatchIssueCommentsQuery } from './watch-issue-comments.query.js';
+import { buildComment, buildIssue, mockIssueRepository } from '../test-helpers.js';
+
+const dtoForIssue = (issueId: number) =>
+  CommentApplicationMapper.toDto(buildComment({ id: `comment-of-${issueId}`, issueId }), new Map());
+
+describe('WatchIssueCommentsUseCase', () => {
+  let issueRepository: IIssueRepository;
+  let commentEventsService: CommentEventsService;
+  let useCase: WatchIssueCommentsUseCase;
+
+  beforeEach(() => {
+    issueRepository = mockIssueRepository();
+    commentEventsService = new CommentEventsService();
+    useCase = new WatchIssueCommentsUseCase(issueRepository, commentEventsService);
+  });
+
+  it('streams only events of the requested issue', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+    const received: CommentEvent[] = [];
+
+    const events$ = await useCase.execute(new WatchIssueCommentsQuery(1, 'user-1'));
+    events$.subscribe((event) => received.push(event));
+
+    commentEventsService.emit('comment.created', dtoForIssue(1));
+    commentEventsService.emit('comment.created', dtoForIssue(2));
+
+    expect(received.map((event) => event.comment.id)).toEqual(['comment-of-1']);
+  });
+
+  it('throws IssueNotFoundException when the issue is not visible to the user', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(null);
+
+    await expect(useCase.execute(new WatchIssueCommentsQuery(1, 'user-2'))).rejects.toThrow(IssueNotFoundException);
+  });
+});

src/modules/comment/application/use-cases/watch-issue-comments/watch-issue-comments.use-case.ts

@@ -0,0 +1,31 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { filter, type Observable } from 'rxjs';
+import {
+  ISSUE_REPOSITORY,
+  type IIssueRepository,
+} from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { WatchIssueCommentsQuery } from './watch-issue-comments.query.js';
+import { type CommentEvent, CommentEventsService } from '../../services/comment-events.service.js';
+
+/**
+ * Поток событий комментариев одной задачи для SSE. Доступ к задаче
+ * проверяется один раз — при подключении.
+ */
+@Injectable()
+export class WatchIssueCommentsUseCase {
+  constructor(
+    @Inject(ISSUE_REPOSITORY)
+    private readonly issueRepository: IIssueRepository,
+    private readonly commentEventsService: CommentEventsService,
+  ) {}
+
+  async execute(query: WatchIssueCommentsQuery): Promise<Observable<CommentEvent>> {
+    const issue = await this.issueRepository.findById(query.issueId, query.userId);
+    if (!issue) {
+      throw new IssueNotFoundException(query.issueId);
+    }
+
+    return this.commentEventsService.onEvents().pipe(filter((event) => event.comment.issueId === query.issueId));
+  }
+}

src/modules/comment/comment.module.ts

@@ -0,0 +1,40 @@
+import { Module } from '@nestjs/common';
+import { PrismaModule } from '../../common/prisma-adapter/prisma.module.js';
+import { IssueModule } from '../issue/issue.module.js';
+import { UserModule } from '../user/user.module.js';
+import { FileModule } from '../file/file.module.js';
+import { COMMENT_REPOSITORY } from './domain/repositories/comment.repository.interface.js';
+import { CommentPrismaRepository } from './infrastructure/persistence/prisma/repositories/comment.prisma-repository.js';
+import { CommentController } from './presentation/controllers/comment.controller.js';
+import { CreateCommentUseCase } from './application/use-cases/create-comment/create-comment.use-case.js';
+import { ListCommentsUseCase } from './application/use-cases/list-comments/list-comments.use-case.js';
+import { UpdateCommentUseCase } from './application/use-cases/update-comment/update-comment.use-case.js';
+import { DeleteCommentUseCase } from './application/use-cases/delete-comment/delete-comment.use-case.js';
+import { WatchIssueCommentsUseCase } from './application/use-cases/watch-issue-comments/watch-issue-comments.use-case.js';
+import { CommentAccessService } from './application/services/comment-access.service.js';
+import { CommentExpanderService } from './application/services/comment-expander.service.js';
+import { CommentEventsService } from './application/services/comment-events.service.js';
+import { CommentAttachmentFileOwnerService } from './application/services/comment-attachment-file-owner.service.js';
+
+@Module({
+  imports: [PrismaModule, IssueModule, UserModule, FileModule],
+  controllers: [CommentController],
+  providers: [
+    CreateCommentUseCase,
+    ListCommentsUseCase,
+    UpdateCommentUseCase,
+    DeleteCommentUseCase,
+    WatchIssueCommentsUseCase,
+    CommentAccessService,
+    CommentExpanderService,
+    CommentEventsService,
+    CommentAttachmentFileOwnerService,
+    {
+      // Domain видит только интерфейс ICommentRepository,
+      // конкретную реализацию (Prisma) подставляет DI-контейнер здесь
+      provide: COMMENT_REPOSITORY,
+      useClass: CommentPrismaRepository,
+    },
+  ],
+})
+export class CommentModule {}

src/modules/comment/domain/entities/comment.entity.spec.ts

@@ -0,0 +1,122 @@
+import { describe, expect, it } from 'vitest';
+import { Comment } from './comment.entity.js';
+import { CommentForbiddenException } from '../exceptions/comment-forbidden.exception.js';
+
+const buildComment = (overrides: Partial<{ authorId: string | null; deletedAt: Date | null }> = {}) =>
+  Comment.reconstitute({
+    id: 'comment-1',
+    content: 'Original',
+    issueId: 1,
+    authorId: overrides.authorId === undefined ? 'user-1' : overrides.authorId,
+    editedAt: null,
+    deletedAt: overrides.deletedAt ?? null,
+    createdAt: new Date('2026-01-01T00:00:00.000Z'),
+    updatedAt: new Date('2026-01-01T00:00:00.000Z'),
+  });
+
+describe('Comment', () => {
+  describe('create', () => {
+    it('creates a new comment without id and edit/delete marks', () => {
+      const comment = Comment.create({ issueId: 1, authorId: 'user-1', content: ' Hello ' });
+
+      expect(comment.id).toBeNull();
+      expect(comment.content).toBe('Hello');
+      expect(comment.editedAt).toBeNull();
+      expect(comment.isDeleted).toBe(false);
+    });
+
+    it('rejects empty content', () => {
+      expect(() => Comment.create({ issueId: 1, authorId: 'user-1', content: '' })).toThrow();
+    });
+  });
+
+  describe('edit', () => {
+    it('changes content and sets editedAt', () => {
+      const comment = buildComment();
+
+      expect(comment.edit('Changed', 'user-1')).toBe(true);
+      expect(comment.content).toBe('Changed');
+      expect(comment.editedAt).toBeInstanceOf(Date);
+    });
+
+    it('is a no-op when content is the same', () => {
+      const comment = buildComment();
+
+      expect(comment.edit(' Original ', 'user-1')).toBe(false);
+      expect(comment.editedAt).toBeNull();
+    });
+
+    it('forbids editing by someone other than the author', () => {
+      expect(() => buildComment().edit('Changed', 'user-2')).toThrow(CommentForbiddenException);
+    });
+
+    it('forbids editing when the author account is deleted', () => {
+      expect(() => buildComment({ authorId: null }).edit('Changed', 'user-1')).toThrow(CommentForbiddenException);
+    });
+
+    it('forbids editing a deleted comment', () => {
+      expect(() => buildComment({ deletedAt: new Date() }).edit('Changed', 'user-1')).toThrow();
+    });
+  });
+
+  describe('delete', () => {
+    it('soft-deletes the comment', () => {
+      const comment = buildComment();
+
+      comment.delete('user-1');
+
+      expect(comment.isDeleted).toBe(true);
+      expect(comment.deletedAt).toBeInstanceOf(Date);
+    });
+
+    it('forbids deletion by someone other than the author', () => {
+      expect(() => buildComment().delete('user-2')).toThrow(CommentForbiddenException);
+    });
+  });
+
+  describe('attachments', () => {
+    it('creates a comment with deduplicated files', () => {
+      const comment = Comment.create({ issueId: 1, authorId: 'user-1', content: 'Hi', fileIds: ['a', 'b', 'a'] });
+
+      expect(comment.fileIds).toEqual(['a', 'b']);
+    });
+
+    it('limits the number of files', () => {
+      const fileIds = Array.from({ length: Comment.MAX_ATTACHMENTS + 1 }, (_, i) => `f${i}`);
+
+      expect(() => Comment.create({ issueId: 1, authorId: 'user-1', content: 'Hi', fileIds })).toThrow();
+    });
+
+    it('treats a changed file set as an edit, even with the same text', () => {
+      const comment = buildComment();
+
+      expect(comment.edit('Original', 'user-1', ['a'])).toBe(true);
+      expect(comment.fileIds).toEqual(['a']);
+      expect(comment.editedAt).toBeInstanceOf(Date);
+    });
+
+    it('keeps files when fileIds is not passed', () => {
+      const comment = buildComment();
+      comment.edit('Original', 'user-1', ['a']);
+
+      expect(comment.edit('Changed', 'user-1')).toBe(true);
+      expect(comment.fileIds).toEqual(['a']);
+    });
+
+    it('reports no change for the same text and files', () => {
+      const comment = buildComment();
+      comment.edit('Original', 'user-1', ['a', 'b']);
+
+      expect(comment.edit('Original', 'user-1', ['a', 'b'])).toBe(false);
+    });
+
+    it('drops files on delete so GC can collect them', () => {
+      const comment = buildComment();
+      comment.edit('Original', 'user-1', ['a']);
+
+      comment.delete('user-1');
+
+      expect(comment.fileIds).toEqual([]);
+    });
+  });
+});

src/modules/comment/domain/entities/comment.entity.ts

@@ -0,0 +1,167 @@
+import { CommentContent } from '../value-objects/comment-content.vo.js';
+import { CommentForbiddenException } from '../exceptions/comment-forbidden.exception.js';
+
+interface CommentProps {
+  id: string | null;
+  content: CommentContent;
+  issueId: number;
+  /** null — автор удалил аккаунт */
+  authorId: string | null;
+  /** Прикреплённые файлы (file-модуль), по времени загрузки */
+  fileIds: string[];
+  editedAt: Date | null;
+  deletedAt: Date | null;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+/**
+ * Комментарий к задаче. Удаление мягкое: запись остаётся (deletedAt),
+ * чтобы в ленте можно было показать «комментарий удалён».
+ *
+ * Вложения — часть комментария: задаются при создании и правке,
+ * снимаются при удалении (тогда осиротевшие файлы удалит GC file-модуля).
+ *
+ * `id` (uuid v7) генерируется базой, поэтому у нового комментария
+ * он равен null до сохранения в репозитории.
+ */
+export class Comment {
+  static readonly MAX_ATTACHMENTS = 10;
+
+  private constructor(private readonly props: CommentProps) {}
+
+  /** Фабричный метод для создания НОВОГО комментария */
+  static create(params: { issueId: number; authorId: string; content: string; fileIds?: string[] }): Comment {
+    const now = new Date();
+
+    return new Comment({
+      id: null,
+      content: CommentContent.create(params.content),
+      issueId: params.issueId,
+      authorId: params.authorId,
+      fileIds: Comment.normalizeFileIds(params.fileIds ?? []),
+      editedAt: null,
+      deletedAt: null,
+      createdAt: now,
+      updatedAt: now,
+    });
+  }
+
+  /** Восстановление сущности из персистентного слоя */
+  static reconstitute(props: {
+    id: string;
+    content: string;
+    issueId: number;
+    authorId: string | null;
+    fileIds?: string[];
+    editedAt: Date | null;
+    deletedAt: Date | null;
+    createdAt: Date;
+    updatedAt: Date;
+  }): Comment {
+    return new Comment({
+      ...props,
+      content: CommentContent.create(props.content),
+      fileIds: [...(props.fileIds ?? [])],
+    });
+  }
+
+  get id(): string | null {
+    return this.props.id;
+  }
+
+  get content(): string {
+    return this.props.content.value;
+  }
+
+  get issueId(): number {
+    return this.props.issueId;
+  }
+
+  get authorId(): string | null {
+    return this.props.authorId;
+  }
+
+  get fileIds(): readonly string[] {
+    return this.props.fileIds;
+  }
+
+  get editedAt(): Date | null {
+    return this.props.editedAt;
+  }
+
+  get deletedAt(): Date | null {
+    return this.props.deletedAt;
+  }
+
+  get isDeleted(): boolean {
+    return this.props.deletedAt !== null;
+  }
+
+  get createdAt(): Date {
+    return this.props.createdAt;
+  }
+
+  get updatedAt(): Date {
+    return this.props.updatedAt;
+  }
+
+  /**
+   * Меняет текст и, если передан fileIds, — набор вложений (целиком).
+   * Возвращает false, если ничего не изменилось.
+   */
+  edit(content: string, userId: string, fileIds?: string[]): boolean {
+    this.assertCanModify(userId);
+
+    const nextContent = CommentContent.create(content);
+    const nextFileIds = fileIds === undefined ? this.props.fileIds : Comment.normalizeFileIds(fileIds);
+
+    const contentChanged = !nextContent.equals(this.props.content);
+    const filesChanged =
+      nextFileIds.length !== this.props.fileIds.length || nextFileIds.some((id, i) => id !== this.props.fileIds[i]);
+
+    if (!contentChanged && !filesChanged) {
+      return false;
+    }
+
+    const now = new Date();
+    this.props.content = nextContent;
+    this.props.fileIds = nextFileIds;
+    this.props.editedAt = now;
+    this.props.updatedAt = now;
+    return true;
+  }
+
+  delete(userId: string): void {
+    this.assertCanModify(userId);
+
+    const now = new Date();
+    this.props.fileIds = [];
+    this.props.deletedAt = now;
+    this.props.updatedAt = now;
+  }
+
+  /**
+   * Без дублей и в порядке загрузки: id файлов — uuid v7, их строковый порядок
+   * совпадает с временем создания. Так порядок одинаков в ответе на create
+   * и при чтении из БД, а сравнение наборов в edit не зависит от порядка у клиента.
+   */
+  private static normalizeFileIds(fileIds: string[]): string[] {
+    const unique = [...new Set(fileIds)].sort();
+    if (unique.length > Comment.MAX_ATTACHMENTS) {
+      throw new Error(`К комментарию можно прикрепить не больше ${Comment.MAX_ATTACHMENTS} файлов`);
+    }
+    return unique;
+  }
+
+  /** Править и удалять комментарий может только его автор, и только пока он не удалён */
+  private assertCanModify(userId: string): void {
+    if (this.isDeleted) {
+      throw new Error('Комментарий уже удалён');
+    }
+
+    if (this.props.authorId !== userId) {
+      throw new CommentForbiddenException(this.props.id ?? 'new');
+    }
+  }
+}

src/modules/comment/domain/exceptions/comment-forbidden.exception.ts

@@ -0,0 +1,6 @@
+export class CommentForbiddenException extends Error {
+  constructor(id: string) {
+    super(`Нет прав на изменение комментария id=${id}`);
+    this.name = 'CommentForbiddenException';
+  }
+}

src/modules/comment/domain/exceptions/comment-not-found.exception.ts

@@ -0,0 +1,6 @@
+export class CommentNotFoundException extends Error {
+  constructor(id: string) {
+    super(`Комментарий с id=${id} не найден`);
+    this.name = 'CommentNotFoundException';
+  }
+}

src/modules/comment/domain/repositories/comment.repository.interface.ts

@@ -0,0 +1,36 @@
+import { Comment } from '../entities/comment.entity.js';
+
+/** Направление пагинации комментариев: forward — от старых к новым, backward — от новых к старым */
+export const COMMENT_LIST_DIRECTIONS = ['forward', 'backward'] as const;
+export type CommentListDirection = (typeof COMMENT_LIST_DIRECTIONS)[number];
+
+/** DI-токен, т.к. интерфейсы стираются при компиляции TS */
+export const COMMENT_REPOSITORY = Symbol('COMMENT_REPOSITORY');
+
+export interface ICommentRepository {
+  /** Возвращает и мягко удалённые комментарии — решение принимает вызывающий */
+  findById(id: string): Promise<Comment | null>;
+  /**
+   * Комментарии задачи от старых к новым, включая удалённые.
+   * Курсорная пагинация. forward: cursor — id последнего полученного комментария,
+   * отдаются более новые. backward: cursor — id самого старого полученного,
+   * отдаются более старые (без cursor — последняя страница). Список всегда
+   * отсортирован от старых к новым.
+   */
+  findByIssue(params: {
+    issueId: number;
+    limit: number;
+    cursor?: string;
+    direction?: CommentListDirection;
+  }): Promise<{ list: Comment[]; nextCursor: string | null }>;
+  /**
+   * Создание и обновление сохраняют и вложения (fileIds) — атомарно с комментарием.
+   * FileNotFoundException, если файл удалили между проверкой и записью.
+   */
+  create(comment: Comment): Promise<Comment>;
+  update(comment: Comment): Promise<void>;
+  /** Задачи неудалённых комментариев, к которым прикреплён файл */
+  findIssueIdsByAttachedFile(fileId: string): Promise<number[]>;
+  /** Подмножество fileIds, прикреплённых хотя бы к одному комментарию */
+  findReferencedFileIds(fileIds: string[]): Promise<string[]>;
+}

src/modules/comment/domain/value-objects/comment-content.vo.spec.ts

@@ -0,0 +1,18 @@
+import { describe, expect, it } from 'vitest';
+import { CommentContent } from './comment-content.vo.js';
+
+describe('CommentContent', () => {
+  it('trims the value', () => {
+    expect(CommentContent.create('  hello  ').value).toBe('hello');
+  });
+
+  it('rejects empty content', () => {
+    expect(() => CommentContent.create('   ')).toThrow('Комментарий не может быть пустым');
+  });
+
+  it('rejects content longer than the limit', () => {
+    expect(() => CommentContent.create('a'.repeat(CommentContent.MAX_LENGTH + 1))).toThrow(
+      `Комментарий не может превышать ${CommentContent.MAX_LENGTH} символов`,
+    );
+  });
+});

src/modules/comment/domain/value-objects/comment-content.vo.ts

@@ -0,0 +1,27 @@
+export class CommentContent {
+  static readonly MAX_LENGTH = 10000;
+
+  private constructor(private readonly _value: string) {}
+
+  static create(value: string): CommentContent {
+    const trimmed = value?.trim();
+
+    if (!trimmed) {
+      throw new Error('Комментарий не может быть пустым');
+    }
+
+    if (trimmed.length > CommentContent.MAX_LENGTH) {
+      throw new Error(`Комментарий не может превышать ${CommentContent.MAX_LENGTH} символов`);
+    }
+
+    return new CommentContent(trimmed);
+  }
+
+  get value(): string {
+    return this._value;
+  }
+
+  equals(other: CommentContent): boolean {
+    return this._value === other.value;
+  }
+}

src/modules/comment/infrastructure/persistence/prisma/mappers/comment.mapper.ts

@@ -0,0 +1,41 @@
+import type { Comment as PrismaComment, Prisma } from '../../../../../../generated/prisma/client.js';
+import { Comment } from '../../../../domain/entities/comment.entity.js';
+
+/** Комментарий вместе с id прикреплённых файлов (см. COMMENT_INCLUDE в репозитории) */
+export type PrismaCommentWithAttachments = PrismaComment & { attachments: { fileId: string }[] };
+
+export class CommentPrismaMapper {
+  static toDomain(record: PrismaCommentWithAttachments): Comment {
+    return Comment.reconstitute({
+      id: record.id,
+      content: record.content,
+      issueId: record.issueId,
+      authorId: record.authorId,
+      fileIds: record.attachments.map((attachment) => attachment.fileId),
+      editedAt: record.editedAt,
+      deletedAt: record.deletedAt,
+      createdAt: record.createdAt,
+      updatedAt: record.updatedAt,
+    });
+  }
+
+  static toCreateInput(comment: Comment): Prisma.CommentUncheckedCreateInput {
+    return {
+      content: comment.content,
+      issueId: comment.issueId,
+      authorId: comment.authorId,
+      createdAt: comment.createdAt,
+      updatedAt: comment.updatedAt,
+      attachments: { create: comment.fileIds.map((fileId) => ({ fileId })) },
+    };
+  }
+
+  static toUpdateInput(comment: Comment): Prisma.CommentUncheckedUpdateInput {
+    return {
+      content: comment.content,
+      editedAt: comment.editedAt,
+      deletedAt: comment.deletedAt,
+      updatedAt: comment.updatedAt,
+    };
+  }
+}

src/modules/comment/infrastructure/persistence/prisma/repositories/comment.prisma-repository.ts

@@ -0,0 +1,129 @@
+import { Injectable } from '@nestjs/common';
+import { PrismaAdapter } from '../../../../../../common/prisma-adapter/prisma.adapter.js';
+import { Prisma } from '../../../../../../generated/prisma/client.js';
+import { Comment } from '../../../../domain/entities/comment.entity.js';
+import type {
+  CommentListDirection,
+  ICommentRepository,
+} from '../../../../domain/repositories/comment.repository.interface.js';
+import { CommentPrismaMapper } from '../mappers/comment.mapper.js';
+import { IssueNotFoundException } from '../../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { FileNotFoundException } from '../../../../../file/domain/exceptions/file-not-found.exception.js';
+
+const FOREIGN_KEY_VIOLATION = 'P2003';
+
+/** Вложения подгружаются вместе с комментарием, по времени загрузки файла (uuid v7) */
+const COMMENT_INCLUDE = {
+  attachments: { select: { fileId: true }, orderBy: { fileId: 'asc' } },
+} satisfies Prisma.CommentInclude;
+
+@Injectable()
+export class CommentPrismaRepository implements ICommentRepository {
+  constructor(private readonly prisma: PrismaAdapter) {}
+
+  async findById(id: string): Promise<Comment | null> {
+    const record = await this.prisma.comment.findUnique({ where: { id }, include: COMMENT_INCLUDE });
+    return record ? CommentPrismaMapper.toDomain(record) : null;
+  }
+
+  async findByIssue(params: {
+    issueId: number;
+    limit: number;
+    cursor?: string;
+    direction?: CommentListDirection;
+  }): Promise<{ list: Comment[]; nextCursor: string | null }> {
+    const limit = Math.max(1, params.limit);
+    const order = params.direction === 'backward' ? 'desc' : 'asc';
+
+    // Берём на одну запись больше, чтобы понять, есть ли следующая страница.
+    // id (uuid v7) — тай-брейкер для комментариев с одинаковым createdAt.
+    const records = await this.prisma.comment.findMany({
+      where: { issueId: params.issueId },
+      include: COMMENT_INCLUDE,
+      orderBy: [{ createdAt: order }, { id: order }],
+      take: limit + 1,
+      ...(params.cursor ? { cursor: { id: params.cursor }, skip: 1 } : {}),
+    });
+
+    const hasMore = records.length > limit;
+    const page = hasMore ? records.slice(0, limit) : records;
+    // Курсор — последняя запись страницы в порядке выборки: для backward это самая старая
+    const nextCursor = hasMore ? page[page.length - 1]!.id : null;
+
+    if (order === 'desc') page.reverse();
+
+    return { list: page.map(CommentPrismaMapper.toDomain), nextCursor };
+  }
+
+  async create(comment: Comment): Promise<Comment> {
+    try {
+      // Вложения создаются вложенной записью — одним атомарным запросом
+      const record = await this.prisma.comment.create({
+        data: CommentPrismaMapper.toCreateInput(comment),
+        include: COMMENT_INCLUDE,
+      });
+
+      return CommentPrismaMapper.toDomain(record);
+    } catch (error) {
+      // Задачу или файл удалили между проверкой доступа и вставкой
+      throw this.mapForeignKeyError(error, comment) ?? error;
+    }
+  }
+
+  async update(comment: Comment): Promise<void> {
+    const id = comment.id as string;
+    const fileIds = [...comment.fileIds];
+
+    try {
+      await this.prisma.$transaction(async (tx) => {
+        await tx.comment.update({
+          where: { id },
+          data: CommentPrismaMapper.toUpdateInput(comment),
+        });
+
+        // Синхронизируем набор вложений: лишние снимаем, новые добавляем
+        await tx.commentAttachment.deleteMany({ where: { commentId: id, fileId: { notIn: fileIds } } });
+        if (fileIds.length > 0) {
+          await tx.commentAttachment.createMany({
+            data: fileIds.map((fileId) => ({ commentId: id, fileId })),
+            skipDuplicates: true,
+          });
+        }
+      });
+    } catch (error) {
+      throw this.mapForeignKeyError(error, comment) ?? error;
+    }
+  }
+
+  async findIssueIdsByAttachedFile(fileId: string): Promise<number[]> {
+    const records = await this.prisma.comment.findMany({
+      where: { deletedAt: null, attachments: { some: { fileId } } },
+      select: { issueId: true },
+      distinct: ['issueId'],
+    });
+    return records.map((record) => record.issueId);
+  }
+
+  async findReferencedFileIds(fileIds: string[]): Promise<string[]> {
+    if (fileIds.length === 0) return [];
+
+    const records = await this.prisma.commentAttachment.findMany({
+      where: { fileId: { in: fileIds } },
+      select: { fileId: true },
+      distinct: ['fileId'],
+    });
+    return records.map((record) => record.fileId);
+  }
+
+  /** Какой FK нарушен — по имени ограничения в meta (comment_attachment_fileId_fkey и т.п.) */
+  private mapForeignKeyError(error: unknown, comment: Comment): Error | null {
+    if (!(error instanceof Prisma.PrismaClientKnownRequestError) || error.code !== FOREIGN_KEY_VIOLATION) {
+      return null;
+    }
+
+    if (JSON.stringify(error.meta ?? {}).includes('fileId')) {
+      return new FileNotFoundException(comment.fileIds.join(', '));
+    }
+    return new IssueNotFoundException(comment.issueId);
+  }
+}

src/modules/comment/presentation/controllers/comment.controller.ts

@@ -0,0 +1,126 @@
+import {
+  Body,
+  Controller,
+  Delete,
+  ForbiddenException,
+  Get,
+  HttpCode,
+  HttpStatus,
+  type MessageEvent,
+  NotFoundException,
+  Param,
+  ParseIntPipe,
+  Patch,
+  Post,
+  Query,
+  Sse,
+  UseGuards,
+} from '@nestjs/common';
+import { Session, type UserSession } from '@thallesp/nestjs-better-auth';
+import { map, type Observable } from 'rxjs';
+import { CreateCommentUseCase } from '../../application/use-cases/create-comment/create-comment.use-case.js';
+import { ListCommentsUseCase } from '../../application/use-cases/list-comments/list-comments.use-case.js';
+import { UpdateCommentUseCase } from '../../application/use-cases/update-comment/update-comment.use-case.js';
+import { DeleteCommentUseCase } from '../../application/use-cases/delete-comment/delete-comment.use-case.js';
+import { WatchIssueCommentsUseCase } from '../../application/use-cases/watch-issue-comments/watch-issue-comments.use-case.js';
+import { CreateCommentCommand } from '../../application/use-cases/create-comment/create-comment.command.js';
+import { ListCommentsQuery } from '../../application/use-cases/list-comments/list-comments.query.js';
+import { UpdateCommentCommand } from '../../application/use-cases/update-comment/update-comment.command.js';
+import { DeleteCommentCommand } from '../../application/use-cases/delete-comment/delete-comment.command.js';
+import { WatchIssueCommentsQuery } from '../../application/use-cases/watch-issue-comments/watch-issue-comments.query.js';
+import { CreateCommentRequestDto } from '../dto/create-comment.dto.js';
+import { UpdateCommentRequestDto } from '../dto/update-comment.dto.js';
+import { ListCommentsDto } from '../dto/list-comments.dto.js';
+import { CommentNotFoundException } from '../../domain/exceptions/comment-not-found.exception.js';
+import { CommentForbiddenException } from '../../domain/exceptions/comment-forbidden.exception.js';
+import { IssueNotFoundException } from '../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { IssueVisibleGuard } from '../guards/issue-visible.guard.js';
+import { FileNotFoundException } from '../../../file/domain/exceptions/file-not-found.exception.js';
+import { FileForbiddenException } from '../../../file/domain/exceptions/file-forbidden.exception.js';
+
+@Controller()
+export class CommentController {
+  constructor(
+    private readonly createCommentUseCase: CreateCommentUseCase,
+    private readonly listCommentsUseCase: ListCommentsUseCase,
+    private readonly updateCommentUseCase: UpdateCommentUseCase,
+    private readonly deleteCommentUseCase: DeleteCommentUseCase,
+    private readonly watchIssueCommentsUseCase: WatchIssueCommentsUseCase,
+  ) {}
+
+  @Get('issues/:issueId/comments')
+  list(
+    @Param('issueId', ParseIntPipe) issueId: number,
+    @Query() query: ListCommentsDto,
+    @Session() session: UserSession,
+  ) {
+    return this.handleErrors(() =>
+      this.listCommentsUseCase.execute(
+        new ListCommentsQuery(issueId, session.user.id, Number(query.limit), query.cursor, query.direction),
+      ),
+    );
+  }
+
+  @Post('issues/:issueId/comments')
+  create(
+    @Param('issueId', ParseIntPipe) issueId: number,
+    @Body() dto: CreateCommentRequestDto,
+    @Session() session: UserSession,
+  ) {
+    return this.handleErrors(() =>
+      this.createCommentUseCase.execute(new CreateCommentCommand(issueId, session.user.id, dto.content, dto.fileIds)),
+    );
+  }
+
+  /**
+   * SSE-поток комментариев одной задачи: клиент открывает его на странице
+   * задачи и закрывает при уходе. После переподключения клиенту стоит
+   * перезапросить список — события, пришедшие во время обрыва, не повторяются.
+   * Доступ проверяет IssueVisibleGuard — так клиент без доступа получает 404.
+   */
+  @Sse('issues/:issueId/comments/events')
+  @UseGuards(IssueVisibleGuard)
+  events(
+    @Param('issueId', ParseIntPipe) issueId: number,
+    @Session() session: UserSession,
+  ): Promise<Observable<MessageEvent>> {
+    return this.handleErrors(async () => {
+      const events$ = await this.watchIssueCommentsUseCase.execute(
+        new WatchIssueCommentsQuery(issueId, session.user.id),
+      );
+      return events$.pipe(map((event) => ({ type: event.type, data: event.comment })));
+    });
+  }
+
+  @Patch('comments/:id')
+  update(@Param('id') id: string, @Body() dto: UpdateCommentRequestDto, @Session() session: UserSession) {
+    return this.handleErrors(() =>
+      this.updateCommentUseCase.execute(new UpdateCommentCommand(id, session.user.id, dto.content, dto.fileIds)),
+    );
+  }
+
+  @Delete('comments/:id')
+  @HttpCode(HttpStatus.NO_CONTENT)
+  async delete(@Param('id') id: string, @Session() session: UserSession) {
+    await this.handleErrors(() => this.deleteCommentUseCase.execute(new DeleteCommentCommand(id, session.user.id)));
+  }
+
+  /** Транслирует доменные исключения в HTTP-ответ — это забота presentation-слоя */
+  private async handleErrors<T>(fn: () => Promise<T>): Promise<T> {
+    try {
+      return await fn();
+    } catch (error) {
+      if (
+        error instanceof CommentNotFoundException ||
+        error instanceof IssueNotFoundException ||
+        error instanceof FileNotFoundException
+      ) {
+        throw new NotFoundException(error.message);
+      }
+      if (error instanceof CommentForbiddenException || error instanceof FileForbiddenException) {
+        throw new ForbiddenException(error.message);
+      }
+      throw error;
+    }
+  }
+}

src/modules/comment/presentation/dto/create-comment.dto.ts

@@ -0,0 +1,18 @@
+import { ArrayMaxSize, IsArray, IsNotEmpty, IsOptional, IsString, MaxLength } from 'class-validator';
+import { CommentContent } from '../../domain/value-objects/comment-content.vo.js';
+import { Comment } from '../../domain/entities/comment.entity.js';
+
+export class CreateCommentRequestDto {
+  @IsString()
+  @IsNotEmpty()
+  @MaxLength(CommentContent.MAX_LENGTH)
+  content: string;
+
+  /** id файлов, загруженных через POST /files */
+  @IsOptional()
+  @IsArray()
+  @ArrayMaxSize(Comment.MAX_ATTACHMENTS)
+  @IsString({ each: true })
+  @MaxLength(64, { each: true })
+  fileIds?: string[];
+}

src/modules/comment/presentation/dto/list-comments.dto.ts

@@ -0,0 +1,24 @@
+import { IsIn, IsOptional } from 'class-validator';
+import { IntDecorator, StringDecorator } from '../../../../common/decorators/validators.js';
+import {
+  COMMENT_LIST_DIRECTIONS,
+  type CommentListDirection,
+} from '../../domain/repositories/comment.repository.interface.js';
+
+export class ListCommentsDto {
+  @IntDecorator({ isOptional: true, min: 1, max: 100 })
+  limit: number = 50;
+
+  /** id последнего полученного комментария (nextCursor из предыдущего ответа) */
+  @StringDecorator({ isOptional: true })
+  cursor?: string;
+
+  /**
+   * forward — от старых к новым, cursor — последний полученный (новые после него).
+   * backward — страницы от новых к старым (для чата), cursor — самый старый полученный.
+   * В обоих случаях список в ответе отсортирован от старых к новым.
+   */
+  @IsOptional()
+  @IsIn(COMMENT_LIST_DIRECTIONS)
+  direction: CommentListDirection = 'forward';
+}

src/modules/comment/presentation/dto/update-comment.dto.ts

@@ -0,0 +1,18 @@
+import { ArrayMaxSize, IsArray, IsNotEmpty, IsOptional, IsString, MaxLength } from 'class-validator';
+import { CommentContent } from '../../domain/value-objects/comment-content.vo.js';
+import { Comment } from '../../domain/entities/comment.entity.js';
+
+export class UpdateCommentRequestDto {
+  @IsString()
+  @IsNotEmpty()
+  @MaxLength(CommentContent.MAX_LENGTH)
+  content: string;
+
+  /** id файлов, загруженных через POST /files — набор целиком; не передан — не менять */
+  @IsOptional()
+  @IsArray()
+  @ArrayMaxSize(Comment.MAX_ATTACHMENTS)
+  @IsString({ each: true })
+  @MaxLength(64, { each: true })
+  fileIds?: string[];
+}

src/modules/comment/presentation/guards/issue-visible.guard.spec.ts

@@ -0,0 +1,44 @@
+import { describe, expect, it, vi } from 'vitest';
+import { BadRequestException, type ExecutionContext, NotFoundException, UnauthorizedException } from '@nestjs/common';
+import { CommentAccessService } from '../../application/services/comment-access.service.js';
+import { IssueVisibleGuard } from './issue-visible.guard.js';
+
+const buildContext = (params: Record<string, string>, userId?: string) =>
+  ({
+    switchToHttp: () => ({
+      getRequest: () => ({ params, session: userId ? { user: { id: userId } } : undefined }),
+    }),
+  }) as unknown as ExecutionContext;
+
+const buildGuard = (visible: boolean) => {
+  const commentAccess = { isIssueVisible: vi.fn().mockResolvedValue(visible) } as unknown as CommentAccessService;
+  return { guard: new IssueVisibleGuard(commentAccess), commentAccess };
+};
+
+describe('IssueVisibleGuard', () => {
+  it('allows access to a visible issue', async () => {
+    const { guard, commentAccess } = buildGuard(true);
+
+    await expect(guard.canActivate(buildContext({ issueId: '1' }, 'user-1'))).resolves.toBe(true);
+    expect(commentAccess.isIssueVisible).toHaveBeenCalledWith(1, 'user-1');
+  });
+
+  it('throws NotFoundException when the issue is not visible', async () => {
+    const { guard } = buildGuard(false);
+
+    await expect(guard.canActivate(buildContext({ issueId: '1' }, 'user-2'))).rejects.toThrow(NotFoundException);
+  });
+
+  it('throws BadRequestException for a non-numeric issueId', async () => {
+    const { guard, commentAccess } = buildGuard(true);
+
+    await expect(guard.canActivate(buildContext({ issueId: 'abc' }, 'user-1'))).rejects.toThrow(BadRequestException);
+    expect(commentAccess.isIssueVisible).not.toHaveBeenCalled();
+  });
+
+  it('throws UnauthorizedException without a session', async () => {
+    const { guard } = buildGuard(true);
+
+    await expect(guard.canActivate(buildContext({ issueId: '1' }))).rejects.toThrow(UnauthorizedException);
+  });
+});

src/modules/comment/presentation/guards/issue-visible.guard.ts

@@ -0,0 +1,48 @@
+import {
+  BadRequestException,
+  type CanActivate,
+  type ExecutionContext,
+  Injectable,
+  NotFoundException,
+  UnauthorizedException,
+} from '@nestjs/common';
+import type { UserSession } from '@thallesp/nestjs-better-auth';
+import { CommentAccessService } from '../../application/services/comment-access.service.js';
+import { IssueNotFoundException } from '../../../issue/domain/exceptions/issue-not-found.exception.js';
+
+/**
+ * Проверяет доступ к задаче из `:issueId` ДО вызова обработчика.
+ *
+ * Нужен SSE-эндпоинтам: при наличии глобального interceptor'а Nest вызывает
+ * @Sse-обработчик уже после отправки заголовков 200, и ошибка из него доходит
+ * до клиента только как `event: error`. Guard же отвечает честным 404.
+ *
+ * Сессию в request кладёт глобальный AuthGuard, который выполняется раньше.
+ */
+@Injectable()
+export class IssueVisibleGuard implements CanActivate {
+  constructor(private readonly commentAccess: CommentAccessService) {}
+
+  async canActivate(context: ExecutionContext): Promise<boolean> {
+    const request = context
+      .switchToHttp()
+      .getRequest<{ params: Record<string, string | undefined>; session?: UserSession }>();
+
+    const userId = request.session?.user.id;
+    if (!userId) {
+      throw new UnauthorizedException();
+    }
+
+    // Пайпы (ParseIntPipe) выполняются после guard'ов — парсим сами
+    const issueId = Number(request.params.issueId);
+    if (!Number.isInteger(issueId)) {
+      throw new BadRequestException('Validation failed (numeric string is expected)');
+    }
+
+    if (!(await this.commentAccess.isIssueVisible(issueId, userId))) {
+      throw new NotFoundException(new IssueNotFoundException(issueId).message);
+    }
+
+    return true;
+  }
+}

src/modules/file/application/dto/file.dto.ts

@@ -0,0 +1,9 @@
+export class FileDto {
+  id: string;
+  fileName: string;
+  mimeType: string;
+  size: number;
+  /** null — загрузивший удалил аккаунт */
+  uploaderId: string | null;
+  createdAt: Date;
+}

src/modules/file/application/mappers/file-application.mapper.ts

@@ -0,0 +1,16 @@
+import { StoredFile } from '../../domain/entities/stored-file.entity.js';
+import { FileDto } from '../dto/file.dto.js';
+
+export class FileApplicationMapper {
+  /** storageKey — деталь хранилища, наружу не отдаём */
+  static toDto(file: StoredFile): FileDto {
+    return {
+      id: file.id as string,
+      fileName: file.fileName,
+      mimeType: file.mimeType,
+      size: file.size,
+      uploaderId: file.uploaderId,
+      createdAt: file.createdAt,
+    };
+  }
+}

src/modules/file/application/services/file-access.service.spec.ts

@@ -0,0 +1,29 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { IFileRepository } from '../../domain/repositories/file.repository.interface.js';
+import { FileForbiddenException } from '../../domain/exceptions/file-forbidden.exception.js';
+import { FileNotFoundException } from '../../domain/exceptions/file-not-found.exception.js';
+import { FileAccessService } from './file-access.service.js';
+import { buildFile, mockFileRepository, registryWithOwner } from '../use-cases/test-helpers.js';
+
+describe('FileAccessService.getAttachableFile', () => {
+  let fileRepository: IFileRepository;
+  let service: FileAccessService;
+
+  beforeEach(() => {
+    fileRepository = mockFileRepository();
+    service = new FileAccessService(fileRepository, registryWithOwner({ visibleTo: { 'user-2': ['file-1'] } }));
+    vi.mocked(fileRepository.findById).mockResolvedValue(buildFile());
+  });
+
+  it('returns an own file', async () => {
+    await expect(service.getAttachableFile('file-1', 'user-1')).resolves.toMatchObject({ id: 'file-1' });
+  });
+
+  it('forbids attaching a visible file uploaded by someone else', async () => {
+    await expect(service.getAttachableFile('file-1', 'user-2')).rejects.toThrow(FileForbiddenException);
+  });
+
+  it('hides an invisible file', async () => {
+    await expect(service.getAttachableFile('file-1', 'user-3')).rejects.toThrow(FileNotFoundException);
+  });
+});

src/modules/file/application/services/file-access.service.ts

@@ -0,0 +1,44 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { FILE_REPOSITORY, type IFileRepository } from '../../domain/repositories/file.repository.interface.js';
+import { StoredFile } from '../../domain/entities/stored-file.entity.js';
+import { FileNotFoundException } from '../../domain/exceptions/file-not-found.exception.js';
+import { FileOwnerRegistry } from './file-owner.registry.js';
+import { FileDto } from '../dto/file.dto.js';
+import { FileApplicationMapper } from '../mappers/file-application.mapper.js';
+
+@Injectable()
+export class FileAccessService {
+  constructor(
+    @Inject(FILE_REPOSITORY)
+    private readonly fileRepository: IFileRepository,
+    private readonly fileOwners: FileOwnerRegistry,
+  ) {}
+
+  /**
+   * Файл виден загрузившему и всем, кому виден хоть один его владелец
+   * (например, задача, к которой он прикреплён). Иначе — FileNotFoundException,
+   * чтобы не раскрывать существование чужих файлов.
+   */
+  async getVisibleFile(id: string, userId: string): Promise<StoredFile> {
+    const file = await this.fileRepository.findById(id);
+    if (!file) {
+      throw new FileNotFoundException(id);
+    }
+
+    if (file.isUploadedBy(userId) || (await this.fileOwners.isVisibleThroughAnyOwner(id, userId))) {
+      return file;
+    }
+
+    throw new FileNotFoundException(id);
+  }
+
+  /**
+   * Файл, который пользователь может прикрепить к задаче/комментарию:
+   * невидимый — FileNotFoundException, видимый, но чужой — FileForbiddenException.
+   */
+  async getAttachableFile(id: string, userId: string): Promise<FileDto> {
+    const file = await this.getVisibleFile(id, userId);
+    file.assertOwnedBy(userId);
+    return FileApplicationMapper.toDto(file);
+  }
+}

src/modules/file/application/services/file-gc.service.spec.ts

@@ -0,0 +1,61 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import { ConfigService } from '@nestjs/config';
+import type { IFileRepository } from '../../domain/repositories/file.repository.interface.js';
+import type { IFileStorage } from '../../domain/ports/file-storage.port.js';
+import { FileGcService } from './file-gc.service.js';
+import { buildFile, mockFileRepository, mockFileStorage, registryWithOwner } from '../use-cases/test-helpers.js';
+
+describe('FileGcService', () => {
+  let fileRepository: IFileRepository;
+  let fileStorage: IFileStorage;
+  const config = new ConfigService({ FILE_ORPHAN_TTL_HOURS: '24' });
+  const now = new Date('2026-01-10T00:00:00.000Z');
+
+  beforeEach(() => {
+    fileRepository = mockFileRepository();
+    fileStorage = mockFileStorage();
+  });
+
+  it('removes only unreferenced files older than the TTL', async () => {
+    const gc = new FileGcService(fileRepository, fileStorage, registryWithOwner({ referenced: ['kept'] }), config);
+    vi.mocked(fileRepository.findCreatedBefore).mockResolvedValueOnce([
+      buildFile({ id: 'kept' }),
+      buildFile({ id: 'orphan' }),
+    ]);
+
+    const removed = await gc.collect(now);
+
+    expect(fileRepository.findCreatedBefore).toHaveBeenCalledWith({
+      before: new Date('2026-01-09T00:00:00.000Z'),
+      limit: 500,
+      cursor: undefined,
+    });
+    expect(removed).toBe(1);
+    expect(fileStorage.delete).toHaveBeenCalledExactlyOnceWith('files/orphan');
+    expect(fileRepository.delete).toHaveBeenCalledExactlyOnceWith('orphan');
+  });
+
+  it('keeps the row when the object cannot be deleted and goes on', async () => {
+    const gc = new FileGcService(fileRepository, fileStorage, registryWithOwner(), config);
+    vi.mocked(fileRepository.findCreatedBefore).mockResolvedValueOnce([buildFile({ id: 'a' }), buildFile({ id: 'b' })]);
+    vi.mocked(fileStorage.delete).mockRejectedValueOnce(new Error('s3 down'));
+
+    const removed = await gc.collect(now);
+
+    expect(removed).toBe(1);
+    expect(fileRepository.delete).toHaveBeenCalledExactlyOnceWith('b');
+  });
+
+  it('pages through files by cursor', async () => {
+    const gc = new FileGcService(fileRepository, fileStorage, registryWithOwner(), config);
+    const fullBatch = Array.from({ length: 500 }, (_, i) => buildFile({ id: `f${i}` }));
+    vi.mocked(fileRepository.findCreatedBefore)
+      .mockResolvedValueOnce(fullBatch)
+      .mockResolvedValueOnce([buildFile({ id: 'last' })]);
+
+    const removed = await gc.collect(now);
+
+    expect(removed).toBe(501);
+    expect(vi.mocked(fileRepository.findCreatedBefore).mock.calls[1]![0]).toMatchObject({ cursor: 'f499' });
+  });
+});

src/modules/file/application/services/file-gc.service.ts

@@ -0,0 +1,90 @@
+import { Inject, Injectable, Logger } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { Cron, CronExpression } from '@nestjs/schedule';
+import { FILE_REPOSITORY, type IFileRepository } from '../../domain/repositories/file.repository.interface.js';
+import { FILE_STORAGE, type IFileStorage } from '../../domain/ports/file-storage.port.js';
+import { FileOwnerRegistry } from './file-owner.registry.js';
+
+const BATCH_SIZE = 500;
+
+/**
+ * Удаляет файлы-сироты — на которые не ссылается ни один владелец:
+ * загруженные, но так и не прикреплённые, и те, чьи задачи/комментарии
+ * удалены (каскад в БД убирает связь, но не сам файл).
+ *
+ * TTL нужен, чтобы не удалить файл, который пользователь только что загрузил
+ * и вот-вот прикрепит (например, пока пишет комментарий).
+ *
+ * Сначала удаляется объект, потом строка: если упадёт удаление строки,
+ * файл останется сиротой и будет подобран следующим запуском
+ * (удаление объекта идемпотентно). Обратный порядок терял бы объекты навсегда.
+ *
+ * Несколько инстансов приложения могут запустить GC одновременно — это
+ * безопасно, все операции идемпотентны.
+ */
+@Injectable()
+export class FileGcService {
+  private readonly logger = new Logger(FileGcService.name);
+  private readonly orphanTtlMs: number;
+  private running = false;
+
+  constructor(
+    @Inject(FILE_REPOSITORY)
+    private readonly fileRepository: IFileRepository,
+    @Inject(FILE_STORAGE)
+    private readonly fileStorage: IFileStorage,
+    private readonly fileOwners: FileOwnerRegistry,
+    config: ConfigService,
+  ) {
+    this.orphanTtlMs = Number(config.get('FILE_ORPHAN_TTL_HOURS', 24)) * 60 * 60 * 1000;
+  }
+
+  @Cron(CronExpression.EVERY_HOUR)
+  async handleCron(): Promise<void> {
+    if (this.running) return;
+
+    this.running = true;
+    try {
+      const removed = await this.collect();
+      if (removed > 0) {
+        this.logger.log(`Удалено файлов-сирот: ${removed}`);
+      }
+    } catch (error) {
+      this.logger.error('Сборка файлов-сирот упала', error instanceof Error ? error.stack : error);
+    } finally {
+      this.running = false;
+    }
+  }
+
+  /** Возвращает количество удалённых файлов */
+  async collect(now = new Date()): Promise<number> {
+    const before = new Date(now.getTime() - this.orphanTtlMs);
+    let cursor: string | undefined;
+    let removed = 0;
+
+    for (;;) {
+      const batch = await this.fileRepository.findCreatedBefore({ before, limit: BATCH_SIZE, cursor });
+      if (batch.length === 0) break;
+
+      const ids = batch.map((file) => file.id as string);
+      const referenced = await this.fileOwners.findReferenced(ids);
+
+      for (const file of batch) {
+        if (referenced.has(file.id as string)) continue;
+
+        try {
+          await this.fileStorage.delete(file.storageKey);
+          await this.fileRepository.delete(file.id as string);
+          removed++;
+        } catch (error) {
+          this.logger.warn(`Не удалось удалить файл id=${file.id}: ${error instanceof Error ? error.message : error}`);
+        }
+      }
+
+      if (batch.length < BATCH_SIZE) break;
+      cursor = ids[ids.length - 1];
+    }
+
+    return removed;
+  }
+}

src/modules/file/application/services/file-owner.registry.ts

@@ -0,0 +1,49 @@
+import { Injectable } from '@nestjs/common';
+
+/**
+ * Модуль, к сущностям которого привязываются файлы (задачи, комментарии...).
+ * Связи хранятся в его таблицах (issue_attachment и т.п.), file-модуль
+ * о них не знает и спрашивает через этот интерфейс.
+ */
+export interface FileOwner {
+  /** Для логов */
+  readonly name: string;
+  /** Подмножество fileIds, на которые ссылаются сущности этого владельца (для GC) */
+  findReferenced(fileIds: string[]): Promise<string[]>;
+  /** Виден ли файл пользователю через сущность этого владельца */
+  isVisibleThrough(fileId: string, userId: string): Promise<boolean>;
+}
+
+/**
+ * Реестр владельцев файлов. Модуль-владелец регистрируется в onModuleInit:
+ *
+ *   constructor(private readonly fileOwners: FileOwnerRegistry) {}
+ *   onModuleInit() { this.fileOwners.register(this); }
+ *
+ * Важно: файл, на который не ссылается ни один зарегистрированный владелец,
+ * GC считает сиротой. Новый владелец ОБЯЗАН зарегистрироваться.
+ */
+@Injectable()
+export class FileOwnerRegistry {
+  private readonly owners: FileOwner[] = [];
+
+  register(owner: FileOwner): void {
+    this.owners.push(owner);
+  }
+
+  async findReferenced(fileIds: string[]): Promise<Set<string>> {
+    if (fileIds.length === 0) return new Set();
+
+    const results = await Promise.all(this.owners.map((owner) => owner.findReferenced(fileIds)));
+    return new Set(results.flat());
+  }
+
+  async isVisibleThroughAnyOwner(fileId: string, userId: string): Promise<boolean> {
+    for (const owner of this.owners) {
+      if (await owner.isVisibleThrough(fileId, userId)) {
+        return true;
+      }
+    }
+    return false;
+  }
+}

src/modules/file/application/use-cases/delete-file/delete-file.command.ts

@@ -0,0 +1,6 @@
+export class DeleteFileCommand {
+  constructor(
+    public readonly id: string,
+    public readonly userId: string,
+  ) {}
+}

src/modules/file/application/use-cases/delete-file/delete-file.use-case.spec.ts

@@ -0,0 +1,52 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { IFileRepository } from '../../../domain/repositories/file.repository.interface.js';
+import type { IFileStorage } from '../../../domain/ports/file-storage.port.js';
+import { FileForbiddenException } from '../../../domain/exceptions/file-forbidden.exception.js';
+import { FileNotFoundException } from '../../../domain/exceptions/file-not-found.exception.js';
+import { FileAccessService } from '../../services/file-access.service.js';
+import { DeleteFileUseCase } from './delete-file.use-case.js';
+import { DeleteFileCommand } from './delete-file.command.js';
+import { buildFile, mockFileRepository, mockFileStorage, registryWithOwner } from '../test-helpers.js';
+
+describe('DeleteFileUseCase', () => {
+  let fileRepository: IFileRepository;
+  let fileStorage: IFileStorage;
+  let useCase: DeleteFileUseCase;
+
+  beforeEach(() => {
+    fileRepository = mockFileRepository();
+    fileStorage = mockFileStorage();
+    const registry = registryWithOwner({ visibleTo: { 'user-2': ['file-1'] } });
+    useCase = new DeleteFileUseCase(fileRepository, fileStorage, new FileAccessService(fileRepository, registry));
+
+    vi.mocked(fileRepository.findById).mockResolvedValue(buildFile());
+  });
+
+  it('deletes the object first, then the row', async () => {
+    const order: string[] = [];
+    vi.mocked(fileStorage.delete).mockImplementation(async () => void order.push('storage'));
+    vi.mocked(fileRepository.delete).mockImplementation(async () => void order.push('row'));
+
+    await useCase.execute(new DeleteFileCommand('file-1', 'user-1'));
+
+    expect(fileStorage.delete).toHaveBeenCalledWith('files/file-1');
+    expect(fileRepository.delete).toHaveBeenCalledWith('file-1');
+    expect(order).toEqual(['storage', 'row']);
+  });
+
+  it('keeps the row when deleting the object fails, so a retry can finish', async () => {
+    vi.mocked(fileStorage.delete).mockRejectedValue(new Error('s3 down'));
+
+    await expect(useCase.execute(new DeleteFileCommand('file-1', 'user-1'))).rejects.toThrow('s3 down');
+    expect(fileRepository.delete).not.toHaveBeenCalled();
+  });
+
+  it('forbids deleting a visible file uploaded by someone else', async () => {
+    await expect(useCase.execute(new DeleteFileCommand('file-1', 'user-2'))).rejects.toThrow(FileForbiddenException);
+    expect(fileStorage.delete).not.toHaveBeenCalled();
+  });
+
+  it('returns not found for an invisible file', async () => {
+    await expect(useCase.execute(new DeleteFileCommand('file-1', 'user-3'))).rejects.toThrow(FileNotFoundException);
+  });
+});

src/modules/file/application/use-cases/delete-file/delete-file.use-case.ts

@@ -0,0 +1,29 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { FILE_REPOSITORY, type IFileRepository } from '../../../domain/repositories/file.repository.interface.js';
+import { FILE_STORAGE, type IFileStorage } from '../../../domain/ports/file-storage.port.js';
+import { DeleteFileCommand } from './delete-file.command.js';
+import { FileAccessService } from '../../services/file-access.service.js';
+
+/**
+ * Удаляет файл целиком; связи с владельцами уходят каскадом в БД.
+ * Порядок как в FileGcService: сначала объект, потом строка — при сбое
+ * повторный DELETE доведёт дело до конца, объект не потеряется.
+ */
+@Injectable()
+export class DeleteFileUseCase {
+  constructor(
+    @Inject(FILE_REPOSITORY)
+    private readonly fileRepository: IFileRepository,
+    @Inject(FILE_STORAGE)
+    private readonly fileStorage: IFileStorage,
+    private readonly fileAccess: FileAccessService,
+  ) {}
+
+  async execute(command: DeleteFileCommand): Promise<void> {
+    const file = await this.fileAccess.getVisibleFile(command.id, command.userId);
+    file.assertOwnedBy(command.userId);
+
+    await this.fileStorage.delete(file.storageKey);
+    await this.fileRepository.delete(command.id);
+  }
+}

src/modules/file/application/use-cases/download-file/download-file.query.ts

@@ -0,0 +1,6 @@
+export class DownloadFileQuery {
+  constructor(
+    public readonly id: string,
+    public readonly userId: string,
+  ) {}
+}

src/modules/file/application/use-cases/download-file/download-file.use-case.spec.ts

@@ -0,0 +1,63 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { Readable } from 'node:stream';
+import type { IFileRepository } from '../../../domain/repositories/file.repository.interface.js';
+import type { IFileStorage } from '../../../domain/ports/file-storage.port.js';
+import { FileNotFoundException } from '../../../domain/exceptions/file-not-found.exception.js';
+import { FileAccessService } from '../../services/file-access.service.js';
+import { DownloadFileUseCase } from './download-file.use-case.js';
+import { DownloadFileQuery } from './download-file.query.js';
+import { buildFile, mockFileRepository, mockFileStorage, registryWithOwner } from '../test-helpers.js';
+
+describe('DownloadFileUseCase', () => {
+  let fileRepository: IFileRepository;
+  let fileStorage: IFileStorage;
+  let useCase: DownloadFileUseCase;
+  const stream = {} as Readable;
+
+  beforeEach(() => {
+    fileRepository = mockFileRepository();
+    fileStorage = mockFileStorage();
+    const registry = registryWithOwner({ visibleTo: { 'user-2': ['file-1'] } });
+    useCase = new DownloadFileUseCase(fileStorage, new FileAccessService(fileRepository, registry));
+
+    vi.mocked(fileStorage.get).mockResolvedValue(stream);
+  });
+
+  it('lets the uploader download the file', async () => {
+    vi.mocked(fileRepository.findById).mockResolvedValue(buildFile());
+
+    const result = await useCase.execute(new DownloadFileQuery('file-1', 'user-1'));
+
+    expect(fileStorage.get).toHaveBeenCalledWith('files/file-1');
+    expect(result).toMatchObject({ file: { id: 'file-1' }, inline: true, stream });
+  });
+
+  it('lets a user who sees an owner of the file download it', async () => {
+    vi.mocked(fileRepository.findById).mockResolvedValue(buildFile());
+
+    await expect(useCase.execute(new DownloadFileQuery('file-1', 'user-2'))).resolves.toMatchObject({
+      file: { id: 'file-1' },
+    });
+  });
+
+  it('marks non-image files as attachment-only', async () => {
+    vi.mocked(fileRepository.findById).mockResolvedValue(buildFile({ mimeType: 'application/octet-stream' }));
+
+    const result = await useCase.execute(new DownloadFileQuery('file-1', 'user-1'));
+
+    expect(result.inline).toBe(false);
+  });
+
+  it('hides the file from everyone else', async () => {
+    vi.mocked(fileRepository.findById).mockResolvedValue(buildFile());
+
+    await expect(useCase.execute(new DownloadFileQuery('file-1', 'user-3'))).rejects.toThrow(FileNotFoundException);
+    expect(fileStorage.get).not.toHaveBeenCalled();
+  });
+
+  it('throws FileNotFoundException for a missing file', async () => {
+    vi.mocked(fileRepository.findById).mockResolvedValue(null);
+
+    await expect(useCase.execute(new DownloadFileQuery('file-1', 'user-1'))).rejects.toThrow(FileNotFoundException);
+  });
+});

src/modules/file/application/use-cases/download-file/download-file.use-case.ts

@@ -0,0 +1,34 @@
+import type { Readable } from 'node:stream';
+import { Inject, Injectable } from '@nestjs/common';
+import { FILE_STORAGE, type IFileStorage } from '../../../domain/ports/file-storage.port.js';
+import { DownloadFileQuery } from './download-file.query.js';
+import { FileDto } from '../../dto/file.dto.js';
+import { FileApplicationMapper } from '../../mappers/file-application.mapper.js';
+import { FileAccessService } from '../../services/file-access.service.js';
+
+export interface DownloadFileResult {
+  file: FileDto;
+  /** Можно ли показывать в браузере inline, иначе — только скачивание */
+  inline: boolean;
+  stream: Readable;
+}
+
+@Injectable()
+export class DownloadFileUseCase {
+  constructor(
+    @Inject(FILE_STORAGE)
+    private readonly fileStorage: IFileStorage,
+    private readonly fileAccess: FileAccessService,
+  ) {}
+
+  async execute(query: DownloadFileQuery): Promise<DownloadFileResult> {
+    const file = await this.fileAccess.getVisibleFile(query.id, query.userId);
+    const stream = await this.fileStorage.get(file.storageKey);
+
+    return {
+      file: FileApplicationMapper.toDto(file),
+      inline: file.isInlineViewable,
+      stream,
+    };
+  }
+}

src/modules/file/application/use-cases/get-files/get-files.query.ts

@@ -0,0 +1,3 @@
+export class GetFilesQuery {
+  constructor(public readonly ids: string[]) {}
+}

src/modules/file/application/use-cases/get-files/get-files.use-case.ts

@@ -0,0 +1,24 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { FILE_REPOSITORY, type IFileRepository } from '../../../domain/repositories/file.repository.interface.js';
+import { GetFilesQuery } from './get-files.query.js';
+import { FileDto } from '../../dto/file.dto.js';
+import { FileApplicationMapper } from '../../mappers/file-application.mapper.js';
+
+/**
+ * Метаданные файлов по id — для модулей-владельцев, раскрывающих свои связи
+ * в FileDto (по аналогии с GetUsersUseCase). Доступ проверяет вызывающий:
+ * он отдаёт только файлы своих сущностей, видимых пользователю.
+ */
+@Injectable()
+export class GetFilesUseCase {
+  constructor(
+    @Inject(FILE_REPOSITORY)
+    private readonly fileRepository: IFileRepository,
+  ) {}
+
+  async execute(query: GetFilesQuery): Promise<FileDto[]> {
+    const ids = [...new Set(query.ids)];
+    const files = await this.fileRepository.findByIds(ids);
+    return files.map(FileApplicationMapper.toDto);
+  }
+}

src/modules/file/application/use-cases/test-helpers.ts

@@ -0,0 +1,46 @@
+import { vi } from 'vitest';
+import type { IFileRepository } from '../../domain/repositories/file.repository.interface.js';
+import type { IFileStorage } from '../../domain/ports/file-storage.port.js';
+import { StoredFile } from '../../domain/entities/stored-file.entity.js';
+import { FileOwnerRegistry, type FileOwner } from '../services/file-owner.registry.js';
+
+export const buildFile = (
+  overrides: Partial<{ id: string; uploaderId: string | null; mimeType: string; createdAt: Date }> = {},
+) =>
+  StoredFile.reconstitute({
+    id: overrides.id ?? 'file-1',
+    storageKey: `files/${overrides.id ?? 'file-1'}`,
+    fileName: 'photo.png',
+    mimeType: overrides.mimeType ?? 'image/png',
+    size: 10,
+    uploaderId: overrides.uploaderId === undefined ? 'user-1' : overrides.uploaderId,
+    createdAt: overrides.createdAt ?? new Date('2026-01-01T00:00:00.000Z'),
+  });
+
+export const mockFileRepository = (): IFileRepository => ({
+  findById: vi.fn(),
+  findByIds: vi.fn(),
+  findCreatedBefore: vi.fn(),
+  create: vi.fn(),
+  delete: vi.fn(),
+});
+
+export const mockFileStorage = (): IFileStorage => ({
+  put: vi.fn(),
+  get: vi.fn(),
+  delete: vi.fn(),
+});
+
+/** Реестр с одним владельцем, которому видны/принадлежат перечисленные файлы */
+export const registryWithOwner = (params: { referenced?: string[]; visibleTo?: Record<string, string[]> } = {}) => {
+  const owner: FileOwner = {
+    name: 'test',
+    findReferenced: vi.fn(async (ids: string[]) => ids.filter((id) => params.referenced?.includes(id))),
+    isVisibleThrough: vi.fn(async (fileId: string, userId: string) =>
+      Boolean(params.visibleTo?.[userId]?.includes(fileId)),
+    ),
+  };
+  const registry = new FileOwnerRegistry();
+  registry.register(owner);
+  return registry;
+};

src/modules/file/application/use-cases/upload-file/upload-file.command.ts

@@ -0,0 +1,9 @@
+export class UploadFileCommand {
+  constructor(
+    public readonly uploaderId: string,
+    /** Временный файл, куда multer сохранил загрузку. Удаляет его вызывающий */
+    public readonly tempPath: string,
+    public readonly originalName: string,
+    public readonly size: number,
+  ) {}
+}

src/modules/file/application/use-cases/upload-file/upload-file.use-case.spec.ts

@@ -0,0 +1,75 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { IFileRepository } from '../../../domain/repositories/file.repository.interface.js';
+import type { IFileStorage } from '../../../domain/ports/file-storage.port.js';
+import type { IFileTypeDetector } from '../../../domain/ports/file-type-detector.port.js';
+import { StoredFile } from '../../../domain/entities/stored-file.entity.js';
+import { UploadFileUseCase } from './upload-file.use-case.js';
+import { UploadFileCommand } from './upload-file.command.js';
+import { mockFileRepository, mockFileStorage } from '../test-helpers.js';
+
+vi.mock('node:fs', () => ({ createReadStream: vi.fn(() => 'stream') }));
+
+describe('UploadFileUseCase', () => {
+  let fileRepository: IFileRepository;
+  let fileStorage: IFileStorage;
+  let detector: IFileTypeDetector;
+  let useCase: UploadFileUseCase;
+
+  beforeEach(() => {
+    fileRepository = mockFileRepository();
+    fileStorage = mockFileStorage();
+    detector = { detect: vi.fn() };
+    useCase = new UploadFileUseCase(fileRepository, fileStorage, detector);
+
+    vi.mocked(fileRepository.create).mockImplementation(async (file: StoredFile) =>
+      StoredFile.reconstitute({
+        id: 'file-1',
+        storageKey: file.storageKey,
+        fileName: file.fileName,
+        mimeType: file.mimeType,
+        size: file.size,
+        uploaderId: file.uploaderId,
+        createdAt: file.createdAt,
+      }),
+    );
+  });
+
+  it('stores the file under a generated key with the sniffed MIME type', async () => {
+    vi.mocked(detector.detect).mockResolvedValue('image/png');
+
+    const dto = await useCase.execute(new UploadFileCommand('user-1', '/tmp/upload', 'photo.png', 10));
+
+    const [key, , meta] = vi.mocked(fileStorage.put).mock.calls[0]!;
+    expect(key).toMatch(/^files\/[0-9a-f-]{36}$/);
+    expect(meta).toEqual({ contentType: 'image/png', size: 10 });
+    expect(dto).toEqual({
+      id: 'file-1',
+      fileName: 'photo.png',
+      mimeType: 'image/png',
+      size: 10,
+      uploaderId: 'user-1',
+      createdAt: expect.any(Date),
+    });
+    expect(dto).not.toHaveProperty('storageKey');
+  });
+
+  it('falls back to octet-stream for unrecognized content, ignoring the name', async () => {
+    vi.mocked(detector.detect).mockResolvedValue(null);
+
+    const dto = await useCase.execute(new UploadFileCommand('user-1', '/tmp/upload', 'evil.html', 10));
+
+    expect(dto.mimeType).toBe('application/octet-stream');
+  });
+
+  it('removes the stored object when saving the row fails', async () => {
+    vi.mocked(detector.detect).mockResolvedValue('image/png');
+    vi.mocked(fileRepository.create).mockRejectedValue(new Error('db down'));
+
+    await expect(useCase.execute(new UploadFileCommand('user-1', '/tmp/upload', 'photo.png', 10))).rejects.toThrow(
+      'db down',
+    );
+
+    const [key] = vi.mocked(fileStorage.put).mock.calls[0]!;
+    expect(fileStorage.delete).toHaveBeenCalledWith(key);
+  });
+});

src/modules/file/application/use-cases/upload-file/upload-file.use-case.ts

@@ -0,0 +1,64 @@
+import { randomUUID } from 'node:crypto';
+import { createReadStream } from 'node:fs';
+import { Inject, Injectable, Logger } from '@nestjs/common';
+import { FILE_REPOSITORY, type IFileRepository } from '../../../domain/repositories/file.repository.interface.js';
+import { FILE_STORAGE, type IFileStorage } from '../../../domain/ports/file-storage.port.js';
+import { FILE_TYPE_DETECTOR, type IFileTypeDetector } from '../../../domain/ports/file-type-detector.port.js';
+import { StoredFile } from '../../../domain/entities/stored-file.entity.js';
+import { UploadFileCommand } from './upload-file.command.js';
+import { FileDto } from '../../dto/file.dto.js';
+import { FileApplicationMapper } from '../../mappers/file-application.mapper.js';
+
+const UNKNOWN_MIME_TYPE = 'application/octet-stream';
+
+/**
+ * Загружает файл без привязки к владельцу. Прикрепление к задаче/комментарию —
+ * отдельный шаг в модуле-владельце; не прикреплённый файл удалит GC.
+ */
+@Injectable()
+export class UploadFileUseCase {
+  private readonly logger = new Logger(UploadFileUseCase.name);
+
+  constructor(
+    @Inject(FILE_REPOSITORY)
+    private readonly fileRepository: IFileRepository,
+    @Inject(FILE_STORAGE)
+    private readonly fileStorage: IFileStorage,
+    @Inject(FILE_TYPE_DETECTOR)
+    private readonly fileTypeDetector: IFileTypeDetector,
+  ) {}
+
+  async execute(command: UploadFileCommand): Promise<FileDto> {
+    // Заголовку Content-Type от клиента не доверяем. Нераспознанное
+    // (в т.ч. HTML/SVG) хранится как octet-stream и отдаётся только на скачивание.
+    const mimeType = (await this.fileTypeDetector.detect(command.tempPath)) ?? UNKNOWN_MIME_TYPE;
+    const storageKey = `files/${randomUUID()}`;
+
+    await this.fileStorage.put(storageKey, createReadStream(command.tempPath), {
+      contentType: mimeType,
+      size: command.size,
+    });
+
+    try {
+      const file = await this.fileRepository.create(
+        StoredFile.create({
+          storageKey,
+          fileName: command.originalName,
+          mimeType,
+          size: command.size,
+          uploaderId: command.uploaderId,
+        }),
+      );
+
+      return FileApplicationMapper.toDto(file);
+    } catch (error) {
+      // Строки нет — GC этот объект никогда не найдёт, убираем сразу
+      try {
+        await this.fileStorage.delete(storageKey);
+      } catch (cleanupError) {
+        this.logger.warn(`Не удалось удалить объект ${storageKey}: ${String(cleanupError)}`);
+      }
+      throw error;
+    }
+  }
+}

src/modules/file/domain/entities/stored-file.entity.spec.ts

@@ -0,0 +1,43 @@
+import { describe, expect, it } from 'vitest';
+import { StoredFile } from './stored-file.entity.js';
+import { FileForbiddenException } from '../exceptions/file-forbidden.exception.js';
+
+const build = (mimeType = 'image/png', uploaderId: string | null = 'user-1') =>
+  StoredFile.reconstitute({
+    id: 'file-1',
+    storageKey: 'files/key',
+    fileName: 'photo.png',
+    mimeType,
+    size: 10,
+    uploaderId,
+    createdAt: new Date('2026-01-01T00:00:00.000Z'),
+  });
+
+describe('StoredFile', () => {
+  it('creates a new file with sanitized name and no id', () => {
+    const file = StoredFile.create({
+      storageKey: 'files/key',
+      fileName: '../secret/report.pdf',
+      mimeType: 'application/pdf',
+      size: 100,
+      uploaderId: 'user-1',
+    });
+
+    expect(file.id).toBeNull();
+    expect(file.fileName).toBe('report.pdf');
+    expect(file.uploaderId).toBe('user-1');
+  });
+
+  it('allows inline view only for safe image types', () => {
+    expect(build('image/png').isInlineViewable).toBe(true);
+    expect(build('image/svg+xml').isInlineViewable).toBe(false);
+    expect(build('text/html').isInlineViewable).toBe(false);
+    expect(build('application/octet-stream').isInlineViewable).toBe(false);
+  });
+
+  it('treats only the uploader as the owner', () => {
+    expect(() => build().assertOwnedBy('user-1')).not.toThrow();
+    expect(() => build().assertOwnedBy('user-2')).toThrow(FileForbiddenException);
+    expect(() => build('image/png', null).assertOwnedBy('user-1')).toThrow(FileForbiddenException);
+  });
+});

src/modules/file/domain/entities/stored-file.entity.ts

@@ -0,0 +1,112 @@
+import { FileName } from '../value-objects/file-name.vo.js';
+import { FileForbiddenException } from '../exceptions/file-forbidden.exception.js';
+
+interface StoredFileProps {
+  id: string | null;
+  storageKey: string;
+  fileName: FileName;
+  mimeType: string;
+  size: number;
+  /** null — загрузивший удалил аккаунт */
+  uploaderId: string | null;
+  createdAt: Date;
+}
+
+/**
+ * Типы, которые безопасно показывать в браузере inline. Всё остальное
+ * (в т.ч. HTML и SVG — источник stored XSS) отдаётся только на скачивание.
+ */
+const INLINE_MIME_TYPES = new Set(['image/png', 'image/jpeg', 'image/gif', 'image/webp']);
+
+/**
+ * Загруженный файл (не путать с глобальным `File` из Web API).
+ * О владельцах (задача, комментарий...) ничего не знает — связи живут
+ * в модулях-владельцах, см. FileOwnerRegistry.
+ *
+ * `id` (uuid v7) генерирует Prisma, поэтому у нового файла он null до сохранения.
+ */
+export class StoredFile {
+  private constructor(private readonly props: StoredFileProps) {}
+
+  /** Фабричный метод для НОВОГО файла, уже положенного в хранилище */
+  static create(params: {
+    storageKey: string;
+    fileName: string;
+    mimeType: string;
+    size: number;
+    uploaderId: string;
+  }): StoredFile {
+    return new StoredFile({
+      id: null,
+      storageKey: params.storageKey,
+      fileName: FileName.create(params.fileName),
+      mimeType: params.mimeType,
+      size: params.size,
+      uploaderId: params.uploaderId,
+      createdAt: new Date(),
+    });
+  }
+
+  /** Восстановление сущности из персистентного слоя */
+  static reconstitute(props: {
+    id: string;
+    storageKey: string;
+    fileName: string;
+    mimeType: string;
+    size: number;
+    uploaderId: string | null;
+    createdAt: Date;
+  }): StoredFile {
+    return new StoredFile({
+      ...props,
+      fileName: FileName.create(props.fileName),
+    });
+  }
+
+  get id(): string | null {
+    return this.props.id;
+  }
+
+  get storageKey(): string {
+    return this.props.storageKey;
+  }
+
+  get fileName(): string {
+    return this.props.fileName.value;
+  }
+
+  get mimeType(): string {
+    return this.props.mimeType;
+  }
+
+  get size(): number {
+    return this.props.size;
+  }
+
+  get uploaderId(): string | null {
+    return this.props.uploaderId;
+  }
+
+  get createdAt(): Date {
+    return this.props.createdAt;
+  }
+
+  get isInlineViewable(): boolean {
+    return INLINE_MIME_TYPES.has(this.props.mimeType);
+  }
+
+  isUploadedBy(userId: string): boolean {
+    return this.props.uploaderId === userId;
+  }
+
+  /**
+   * Удалить файл или прикрепить его к сущности может только тот, кто его загрузил.
+   * Иначе, увидев файл через одну задачу, можно было бы «перенести» его
+   * в другую и раскрыть людям, которым он не предназначался.
+   */
+  assertOwnedBy(userId: string): void {
+    if (!this.isUploadedBy(userId)) {
+      throw new FileForbiddenException(this.props.id ?? 'new');
+    }
+  }
+}

src/modules/file/domain/exceptions/file-forbidden.exception.ts

@@ -0,0 +1,6 @@
+export class FileForbiddenException extends Error {
+  constructor(id: string) {
+    super(`Нет прав на это действие с файлом id=${id}`);
+    this.name = 'FileForbiddenException';
+  }
+}

src/modules/file/domain/exceptions/file-not-found.exception.ts

@@ -0,0 +1,6 @@
+export class FileNotFoundException extends Error {
+  constructor(id: string) {
+    super(`Файл с id=${id} не найден`);
+    this.name = 'FileNotFoundException';
+  }
+}

src/modules/file/domain/ports/file-storage.port.ts

@@ -0,0 +1,13 @@
+import type { Readable } from 'node:stream';
+
+/** DI-токен, т.к. интерфейсы стираются при компиляции TS */
+export const FILE_STORAGE = Symbol('FILE_STORAGE');
+
+/** Объектное хранилище содержимого файлов (S3-совместимое или локальный диск) */
+export interface IFileStorage {
+  put(key: string, body: Readable, meta: { contentType: string; size: number }): Promise<void>;
+  /** Бросает ошибку сразу, если объекта нет, — до того как ответ начнёт отправляться */
+  get(key: string): Promise<Readable>;
+  /** Идемпотентно: отсутствие объекта не ошибка */
+  delete(key: string): Promise<void>;
+}

src/modules/file/domain/ports/file-type-detector.port.ts

@@ -0,0 +1,8 @@
+/** DI-токен, т.к. интерфейсы стираются при компиляции TS */
+export const FILE_TYPE_DETECTOR = Symbol('FILE_TYPE_DETECTOR');
+
+/** Определяет MIME-тип по содержимому файла, а не по заголовку от клиента */
+export interface IFileTypeDetector {
+  /** null — тип не распознан (в т.ч. все текстовые форматы: HTML, SVG, CSV...) */
+  detect(path: string): Promise<string | null>;
+}

src/modules/file/domain/repositories/file.repository.interface.ts

@@ -0,0 +1,16 @@
+import { StoredFile } from '../entities/stored-file.entity.js';
+
+/** DI-токен, т.к. интерфейсы стираются при компиляции TS */
+export const FILE_REPOSITORY = Symbol('FILE_REPOSITORY');
+
+export interface IFileRepository {
+  findById(id: string): Promise<StoredFile | null>;
+  findByIds(ids: string[]): Promise<StoredFile[]>;
+  /**
+   * Файлы, созданные раньше `before`, по возрастанию id (uuid v7 ≈ время создания).
+   * Курсорная пагинация для GC: cursor — id последнего полученного файла.
+   */
+  findCreatedBefore(params: { before: Date; limit: number; cursor?: string }): Promise<StoredFile[]>;
+  create(file: StoredFile): Promise<StoredFile>;
+  delete(id: string): Promise<void>;
+}

src/modules/file/domain/value-objects/file-name.vo.spec.ts

@@ -0,0 +1,30 @@
+import { describe, expect, it } from 'vitest';
+import { FileName } from './file-name.vo.js';
+
+describe('FileName', () => {
+  it('keeps a regular name, including cyrillic', () => {
+    expect(FileName.create('Отчёт за май.pdf').value).toBe('Отчёт за май.pdf');
+  });
+
+  it('strips directories from the client-supplied path', () => {
+    expect(FileName.create('C:\\Users\\me\\photo.png').value).toBe('photo.png');
+    expect(FileName.create('../../etc/passwd').value).toBe('passwd');
+  });
+
+  it('removes control characters', () => {
+    expect(FileName.create('evil\r\nname\u0000.txt').value).toBe('evilname.txt');
+  });
+
+  it('falls back when nothing is left', () => {
+    expect(FileName.create('').value).toBe(FileName.FALLBACK);
+    expect(FileName.create('  ').value).toBe(FileName.FALLBACK);
+    expect(FileName.create('dir/..').value).toBe(FileName.FALLBACK);
+  });
+
+  it('truncates long names keeping the extension', () => {
+    const name = FileName.create(`${'a'.repeat(300)}.docx`).value;
+
+    expect([...name]).toHaveLength(FileName.MAX_LENGTH);
+    expect(name.endsWith('.docx')).toBe(true);
+  });
+});

src/modules/file/domain/value-objects/file-name.vo.ts

@@ -0,0 +1,52 @@
+/**
+ * Оригинальное имя файла — только для отображения и Content-Disposition.
+ * В ключ хранилища не попадает, поэтому достаточно убрать путь и
+ * управляющие символы, а не экранировать всё подряд.
+ */
+export class FileName {
+  static readonly MAX_LENGTH = 255;
+  static readonly FALLBACK = 'file';
+
+  private constructor(private readonly _value: string) {}
+
+  static create(value: string): FileName {
+    const baseName = (value ?? '').split(/[/\\]/).pop() ?? '';
+    const cleaned = Array.from(baseName.normalize('NFC'))
+      .filter((char) => !FileName.isControl(char))
+      .join('')
+      .trim();
+
+    if (!cleaned || cleaned === '.' || cleaned === '..') {
+      return new FileName(FileName.FALLBACK);
+    }
+
+    return new FileName(FileName.truncate(cleaned));
+  }
+
+  /** C0-управляющие символы и DEL: переводы строк ломают заголовки, \0 — пути */
+  private static isControl(char: string): boolean {
+    const code = char.codePointAt(0)!;
+    return code <= 0x1f || code === 0x7f;
+  }
+
+  /** Обрезает длинное имя, сохраняя расширение */
+  private static truncate(name: string): string {
+    const chars = Array.from(name);
+    if (chars.length <= FileName.MAX_LENGTH) {
+      return name;
+    }
+
+    const dot = name.lastIndexOf('.');
+    // Array.from, а не split(''): длина в code points, суррогатные пары не рвём
+    const ext = dot > 0 ? Array.from(name.slice(dot)) : [];
+    if (ext.length === 0 || ext.length > 16) {
+      return chars.slice(0, FileName.MAX_LENGTH).join('');
+    }
+
+    return chars.slice(0, FileName.MAX_LENGTH - ext.length).join('') + ext.join('');
+  }
+
+  get value(): string {
+    return this._value;
+  }
+}

src/modules/file/file.module.ts

@@ -0,0 +1,67 @@
+import { tmpdir } from 'node:os';
+import { Module } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { MulterModule } from '@nestjs/platform-express';
+import { PrismaModule } from '../../common/prisma-adapter/prisma.module.js';
+import { FILE_REPOSITORY } from './domain/repositories/file.repository.interface.js';
+import { FILE_STORAGE } from './domain/ports/file-storage.port.js';
+import { FILE_TYPE_DETECTOR } from './domain/ports/file-type-detector.port.js';
+import { FilePrismaRepository } from './infrastructure/persistence/prisma/repositories/file.prisma-repository.js';
+import { createFileStorage } from './infrastructure/storage/file-storage.factory.js';
+import { FileTypeDetector } from './infrastructure/storage/file-type.detector.js';
+import { FileController } from './presentation/controllers/file.controller.js';
+import { UploadFileUseCase } from './application/use-cases/upload-file/upload-file.use-case.js';
+import { DownloadFileUseCase } from './application/use-cases/download-file/download-file.use-case.js';
+import { DeleteFileUseCase } from './application/use-cases/delete-file/delete-file.use-case.js';
+import { GetFilesUseCase } from './application/use-cases/get-files/get-files.use-case.js';
+import { FileAccessService } from './application/services/file-access.service.js';
+import { FileGcService } from './application/services/file-gc.service.js';
+import { FileOwnerRegistry } from './application/services/file-owner.registry.js';
+
+@Module({
+  imports: [
+    PrismaModule,
+    MulterModule.registerAsync({
+      inject: [ConfigService],
+      useFactory: (config: ConfigService) => ({
+        // Загрузка пишется во временный файл, а не в память: тип определяем
+        // по содержимому, размер известен заранее, память не зависит от размера файла
+        dest: tmpdir(),
+        // Без этого multer декодирует имя файла как latin1 и ломает кириллицу
+        defParamCharset: 'utf8',
+        limits: {
+          fileSize: Number(config.get('FILE_MAX_SIZE_MB', 25)) * 1024 * 1024,
+          files: 1,
+        },
+      }),
+    }),
+  ],
+  controllers: [FileController],
+  providers: [
+    UploadFileUseCase,
+    DownloadFileUseCase,
+    DeleteFileUseCase,
+    GetFilesUseCase,
+    FileAccessService,
+    FileGcService,
+    FileOwnerRegistry,
+    {
+      // Domain видит только интерфейсы, конкретные реализации подставляет DI-контейнер здесь
+      provide: FILE_REPOSITORY,
+      useClass: FilePrismaRepository,
+    },
+    {
+      provide: FILE_STORAGE,
+      inject: [ConfigService],
+      useFactory: createFileStorage,
+    },
+    {
+      provide: FILE_TYPE_DETECTOR,
+      useClass: FileTypeDetector,
+    },
+  ],
+  // Модули-владельцы (issue, comment) регистрируются в реестре,
+  // проверяют прикрепляемые файлы и раскрывают связи в FileDto
+  exports: [FileOwnerRegistry, FileAccessService, GetFilesUseCase],
+})
+export class FileModule {}

src/modules/file/infrastructure/persistence/prisma/mappers/file.mapper.ts

@@ -0,0 +1,27 @@
+import type { File as PrismaFile, Prisma } from '../../../../../../generated/prisma/client.js';
+import { StoredFile } from '../../../../domain/entities/stored-file.entity.js';
+
+export class FilePrismaMapper {
+  static toDomain(record: PrismaFile): StoredFile {
+    return StoredFile.reconstitute({
+      id: record.id,
+      storageKey: record.storageKey,
+      fileName: record.fileName,
+      mimeType: record.mimeType,
+      size: record.size,
+      uploaderId: record.uploaderId,
+      createdAt: record.createdAt,
+    });
+  }
+
+  static toCreateInput(file: StoredFile): Prisma.FileUncheckedCreateInput {
+    return {
+      storageKey: file.storageKey,
+      fileName: file.fileName,
+      mimeType: file.mimeType,
+      size: file.size,
+      uploaderId: file.uploaderId,
+      createdAt: file.createdAt,
+    };
+  }
+}

src/modules/file/infrastructure/persistence/prisma/repositories/file.prisma-repository.ts

@@ -0,0 +1,46 @@
+import { Injectable } from '@nestjs/common';
+import { PrismaAdapter } from '../../../../../../common/prisma-adapter/prisma.adapter.js';
+import { StoredFile } from '../../../../domain/entities/stored-file.entity.js';
+import { IFileRepository } from '../../../../domain/repositories/file.repository.interface.js';
+import { FilePrismaMapper } from '../mappers/file.mapper.js';
+
+@Injectable()
+export class FilePrismaRepository implements IFileRepository {
+  constructor(private readonly prisma: PrismaAdapter) {}
+
+  async findById(id: string): Promise<StoredFile | null> {
+    const record = await this.prisma.file.findUnique({ where: { id } });
+    return record ? FilePrismaMapper.toDomain(record) : null;
+  }
+
+  async findByIds(ids: string[]): Promise<StoredFile[]> {
+    if (ids.length === 0) return [];
+
+    const records = await this.prisma.file.findMany({ where: { id: { in: ids } } });
+    return records.map(FilePrismaMapper.toDomain);
+  }
+
+  async findCreatedBefore(params: { before: Date; limit: number; cursor?: string }): Promise<StoredFile[]> {
+    const records = await this.prisma.file.findMany({
+      where: { createdAt: { lt: params.before } },
+      orderBy: { id: 'asc' },
+      take: Math.max(1, params.limit),
+      ...(params.cursor ? { cursor: { id: params.cursor }, skip: 1 } : {}),
+    });
+
+    return records.map(FilePrismaMapper.toDomain);
+  }
+
+  async create(file: StoredFile): Promise<StoredFile> {
+    const record = await this.prisma.file.create({
+      data: FilePrismaMapper.toCreateInput(file),
+    });
+
+    return FilePrismaMapper.toDomain(record);
+  }
+
+  async delete(id: string): Promise<void> {
+    // deleteMany не падает, если строку уже удалил параллельный запрос/GC
+    await this.prisma.file.deleteMany({ where: { id } });
+  }
+}

src/modules/file/infrastructure/storage/file-storage.factory.ts

@@ -0,0 +1,26 @@
+import { ConfigService } from '@nestjs/config';
+import type { IFileStorage } from '../../domain/ports/file-storage.port.js';
+import { LocalFileStorage } from './local-file-storage.js';
+import { S3FileStorage } from './s3-file-storage.js';
+
+/** FILE_STORAGE=s3 — S3-совместимое хранилище, иначе локальный диск */
+export function createFileStorage(config: ConfigService): IFileStorage {
+  const driver = config.get<string>('FILE_STORAGE', 'local');
+
+  if (driver === 's3') {
+    return new S3FileStorage({
+      endpoint: config.get<string>('S3_ENDPOINT') || undefined,
+      region: config.get<string>('S3_REGION', 'us-east-1'),
+      bucket: config.getOrThrow<string>('S3_BUCKET'),
+      accessKeyId: config.getOrThrow<string>('S3_ACCESS_KEY_ID'),
+      secretAccessKey: config.getOrThrow<string>('S3_SECRET_ACCESS_KEY'),
+      forcePathStyle: config.get<string>('S3_FORCE_PATH_STYLE', 'true') !== 'false',
+    });
+  }
+
+  if (driver !== 'local') {
+    throw new Error(`Неизвестный FILE_STORAGE=${driver}, ожидается local | s3`);
+  }
+
+  return new LocalFileStorage(config.get<string>('FILE_STORAGE_LOCAL_DIR', './storage'));
+}

src/modules/file/infrastructure/storage/file-type.detector.ts

@@ -0,0 +1,11 @@
+import { Injectable } from '@nestjs/common';
+import { fileTypeFromFile } from 'file-type';
+import type { IFileTypeDetector } from '../../domain/ports/file-type-detector.port.js';
+
+/** Определение типа по сигнатуре (magic bytes) через file-type */
+@Injectable()
+export class FileTypeDetector implements IFileTypeDetector {
+  async detect(path: string): Promise<string | null> {
+    return (await fileTypeFromFile(path))?.mime ?? null;
+  }
+}