feat：完成大部分数据文件上传解析功能

app/api/files.py

@@ -0,0 +1,95 @@
+"""数据文件接口：上传限制、上传解析、列出、查看、删除，见 docs/screen-agent/data-files.md 第 5 节"""
+
+from typing import Annotated, get_args
+
+from fastapi import APIRouter, Depends, File, Form, Query, Request, UploadFile
+
+from app.common.response import ApiResponse, success_response
+from app.core.auth import get_current_user
+from app.datafiles.service import MAX_FILES_PER_CONVERSATION, DataFileService
+from app.schemas.base import NonBlankString
+from app.schemas.data_file import (
+    DataFileDetail,
+    DataFileInfo,
+    DataFileLimits,
+    DataFileList,
+    DataFileRecord,
+    DataFormat,
+)
+from app.schemas.user import CurrentUser
+
+# 上传限制不需要登录，单独一个路由；要先于 /files/{file_id} 注册
+limits_router = APIRouter(prefix="/files", tags=["DataFile"])
+router = APIRouter(prefix="/files", tags=["DataFile"])
+
+# 文件选择框的过滤条件；后端按文件内容识别格式，不看扩展名
+ACCEPT = ".csv,.tsv,.txt,.xlsx,.xls,.xlsb,.json,.jsonl,.ndjson,.parquet"
+
+
+def _service(request: Request) -> DataFileService:
+    return request.app.state.data_file_service
+
+
+def _detail(record: DataFileRecord) -> DataFileDetail:
+    # 按接口模型重新校验，去掉 owner_id、sha256、列概况等只在后端用的字段
+    return DataFileDetail.model_validate(record.model_dump())
+
+
+@limits_router.get("/limits")
+async def get_limits(request: Request) -> ApiResponse[DataFileLimits]:
+    return success_response(
+        DataFileLimits(
+            max_size_mb=_service(request).max_mb,
+            max_files_per_conversation=MAX_FILES_PER_CONVERSATION,
+            formats=list(get_args(DataFormat)),
+            accept=ACCEPT,
+        )
+    )
+
+
+@router.post("")
+async def upload_file(
+    request: Request,
+    conversation_id: Annotated[NonBlankString, Form()],
+    file: Annotated[UploadFile, File()],
+    user: Annotated[CurrentUser, Depends(get_current_user)],
+) -> ApiResponse[DataFileDetail]:
+    record = await _service(request).upload(
+        user.id, conversation_id, file.filename, file.file
+    )
+    return success_response(_detail(record))
+
+
+@router.get("")
+async def list_files(
+    request: Request,
+    conversation_id: Annotated[NonBlankString, Query()],
+    user: Annotated[CurrentUser, Depends(get_current_user)],
+) -> ApiResponse[DataFileList]:
+    records = await _service(request).list_files(user.id, conversation_id)
+    return success_response(
+        DataFileList(
+            files=[
+                DataFileInfo.model_validate(record.model_dump()) for record in records
+            ]
+        )
+    )
+
+
+@router.get("/{file_id}")
+async def get_file(
+    file_id: str,
+    request: Request,
+    user: Annotated[CurrentUser, Depends(get_current_user)],
+) -> ApiResponse[DataFileDetail]:
+    return success_response(_detail(await _service(request).get_file(user.id, file_id)))
+
+
+@router.delete("/{file_id}")
+async def delete_file(
+    file_id: str,
+    request: Request,
+    user: Annotated[CurrentUser, Depends(get_current_user)],
+) -> ApiResponse[dict]:
+    await _service(request).delete_file(user.id, file_id)
+    return success_response()