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2026-09-01 13:00:36 +08:00
parent 1d8621717a
commit dfd38c99a0
35 changed files with 3141 additions and 21 deletions
@@ -0,0 +1,202 @@
+"""文档服务：上传、删除、配额管理。"""
+
+import hashlib
+from pathlib import Path
+
+import filetype
+
+from app.core.config import get_settings
+from app.core.errors import (
+    FileTooLargeError,
+    FileTypeUnsupportedError,
+    NotFoundError,
+    StorageQuotaExceededError,
+)
+from app.core.security import decrypt_token, encrypt_token, generate_token, hash_token
+from app.models.document import Document
+from app.models.user import User
+from app.repositories.doc_repo import DocumentRepository
+from app.repositories.kb_repo import KnowledgeBaseRepository
+from app.storage.local_storage import get_storage
+from app.storage.object_keys import original_object_key
+from sqlalchemy.orm import Session
+
+# 允许的文件扩展名
+ALLOWED_EXTENSIONS = {".docx", ".pdf"}
+ALLOWED_MIMES = {
+    "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
+    "application/pdf",
+}
+
+
+class DocumentService:
+    def __init__(self, session: Session) -> None:
+        self._session = session
+        self._doc_repo = DocumentRepository(session)
+        self._kb_repo = KnowledgeBaseRepository(session)
+
+    def upload(
+        self,
+        user: User,
+        kb_id: str,
+        filename: str,
+        content: bytes,
+    ) -> Document:
+        """上传文档。
+
+        流程：校验 KB 归属 → 文件大小 → 扩展名/MIME → 配额 → SHA256 → 存储 → 入库
+        """
+        # 校验 KB 归属
+        kb = self._kb_repo.get_by_id(kb_id)
+        if kb is None or kb.user_id != user.id or kb.status == "DELETED":
+            raise NotFoundError("知识库不存在。")
+
+        settings = get_settings()
+
+        # 文件大小
+        if len(content) > settings.default_max_file_size:
+            raise FileTooLargeError(
+                f"单文件大小超出限制（最大 {settings.default_max_file_size // (1024*1024)}MB）。"
+            )
+
+        # 扩展名
+        ext = Path(filename).suffix.lower()
+        if ext not in ALLOWED_EXTENSIONS:
+            raise FileTypeUnsupportedError(
+                f"不支持的文件类型 '{ext}'。当前支持：{', '.join(sorted(ALLOWED_EXTENSIONS))}"
+            )
+
+        # MIME 嗅探（前 8KB）——仅用于辅助校验，扩展名为主
+        kind = filetype.guess(content[:8192])
+        detected_mime = kind.mime if kind else ""
+        # .docx 底层是 ZIP，filetype 会识别为 application/zip，这是正常的
+        # 只在检测到明确不属于文档类型的 MIME 时才拒绝（如图片、视频等）
+        BLOCKED_MIMES = {"image/jpeg", "image/png", "video/mp4", "audio/mpeg", "application/x-executable"}
+        if detected_mime in BLOCKED_MIMES:
+            raise FileTypeUnsupportedError(f"文件内容类型不受支持：{detected_mime}")
+
+        # 配额检查（原子 SQL）
+        file_size = len(content)
+        self._check_quota(user, file_size)
+
+        # SHA256
+        sha256 = hashlib.sha256(content).hexdigest()
+
+        # 生成文档 token
+        doc_token = generate_token()
+        doc_token_hash = hash_token(doc_token)
+        doc_token_encrypted = encrypt_token(doc_token)
+        doc_token_hint = doc_token[-8:] if len(doc_token) >= 8 else doc_token
+
+        # 存储原始文件
+        storage_key = original_object_key(
+            user_id=user.id,
+            knowledge_base_id=kb_id,
+            document_id="pending",  # 先存文件，入库后更新路径
+            original_filename=filename,
+        )
+        storage = get_storage()
+        storage.save(storage_key, content)
+
+        # 入库
+        doc = self._doc_repo.create(
+            knowledge_base_id=kb_id,
+            user_id=user.id,
+            original_filename=filename,
+            storage_path=storage_key,
+            file_size=file_size,
+            mime_type=detected_mime or "application/octet-stream",
+            file_ext=ext,
+            sha256=sha256,
+            doc_token_hash=doc_token_hash,
+            doc_token_encrypted=doc_token_encrypted,
+            doc_token_hint=doc_token_hint,
+        )
+
+        # 更新存储路径中的 document_id
+        actual_key = original_object_key(
+            user_id=user.id,
+            knowledge_base_id=kb_id,
+            document_id=doc.id,
+            original_filename=filename,
+        )
+        # 移动文件到正确路径
+        if actual_key != storage_key:
+            storage.save(actual_key, storage.delete(storage_key) or content)
+            doc.storage_path = actual_key
+
+        # 扣减配额（原子 SQL）
+        self._deduct_quota(user, file_size)
+
+        self._session.commit()
+
+        # 同步解析文档（MVP：阻塞式）
+        self._process_document(doc)
+
+        return doc
+
+    def get_or_404(self, doc_id: str, user: User) -> Document:
+        doc = self._doc_repo.get_by_id(doc_id)
+        if doc is None or doc.user_id != user.id or doc.status == "DELETED":
+            raise NotFoundError("文档不存在。")
+        return doc
+
+    def list_by_knowledge_base(
+        self, kb_id: str, user: User, *, page: int = 1, page_size: int = 50
+    ):
+        # 校验 KB 归属
+        kb = self._kb_repo.get_by_id(kb_id)
+        if kb is None or kb.user_id != user.id or kb.status == "DELETED":
+            raise NotFoundError("知识库不存在。")
+        return self._doc_repo.list_by_knowledge_base(kb_id, page=page, page_size=page_size)
+
+    def delete(self, doc_id: str, user: User) -> None:
+        doc = self.get_or_404(doc_id, user)
+        file_size = doc.file_size
+        self._doc_repo.delete(doc)
+        # 回补配额
+        self._restore_quota(user, file_size)
+        self._session.commit()
+
+    def _check_quota(self, user: User, file_size: int) -> None:
+        settings = get_settings()
+        if user.storage_used + file_size > settings.default_storage_quota:
+            raise StorageQuotaExceededError(
+                f"存储空间不足（已用 {user.storage_used // (1024*1024)}MB，"
+                f"上传 {file_size // (1024*1024)}MB，"
+                f"总配额 {settings.default_storage_quota // (1024*1024)}MB）。"
+            )
+
+    def _deduct_quota(self, user: User, file_size: int) -> None:
+        """原子扣减配额。"""
+        from sqlalchemy import update
+
+        stmt = (
+            update(User)
+            .where(User.id == user.id, User.storage_used + file_size <= get_settings().default_storage_quota)
+            .values(storage_used=User.storage_used + file_size)
+        )
+        result = self._session.execute(stmt)
+        if result.rowcount == 0:
+            raise StorageQuotaExceededError("存储空间不足（并发上传导致）。")
+        # 更新本地对象
+        user.storage_used += file_size
+
+    def _restore_quota(self, user: User, file_size: int) -> None:
+        """回补配额。"""
+        from sqlalchemy import update
+
+        stmt = (
+            update(User)
+            .where(User.id == user.id)
+            .values(storage_used=User.storage_used - file_size)
+        )
+        self._session.execute(stmt)
+        user.storage_used = max(0, user.storage_used - file_size)
+
+    def _process_document(self, doc: Document) -> None:
+        """同步处理文档（MVP 阶段，阻塞式）。"""
+        from app.processors.local_processor import LocalDocumentProcessor
+
+        processor = LocalDocumentProcessor(self._session)
+        processor.process(doc.id)