style: auto-format with black + isort + prettier [skip ci-format-check]

- Change CreateAssetRequest.project_id from required to optional
- Auto-derive project_id from library.project_id when not provided
- Reorder validation: fetch library first, then derive project_id
- Add 4 unit tests covering all scenarios
- Fixes 422 error when frontend creates asset without project_id

apps/api/app/api/routes/assets.py

@@ -671,20 +671,28 @@ def create_asset(
     asset_library_repository: Any = Depends(get_asset_library_repository),
     project_repository: Any = Depends(get_project_repository),
 ) -> AssetResponse:
-    project = project_repository.find_by_id(request.project_id)
+    # 先获取素材库，用于推导 project_id（前端可能不传）
+    library = asset_library_repository.get(request.library_id)
+    if library is None:
+        raise HTTPException(status_code=404, detail=f"AssetLibrary {request.library_id} not found")
+
+    # project_id 自动推导：优先用请求值，否则从 library 关联的项目获取
+    project_id = request.project_id or library.project_id
+
+    project = project_repository.find_by_id(project_id)
     if project is None:
-        raise HTTPException(status_code=404, detail=f"Project {request.project_id} not found")
+        raise HTTPException(status_code=404, detail=f"Project {project_id} not found")
     if not project.can_access(authenticated_user.user.id):
         raise HTTPException(status_code=403, detail="Access denied to project")
 
-    library = asset_library_repository.get(request.library_id)
-    if library is None or library.project_id != request.project_id:
-        raise HTTPException(status_code=404, detail=f"AssetLibrary {request.library_id} not found")
+    # 确保 library 和 project 归属一致
+    if library.project_id != project_id:
+        raise HTTPException(status_code=400, detail="AssetLibrary does not belong to the specified project")
 
     use_case = CreateAssetUseCase(asset_repository)
     item = use_case.execute(
         CreateAssetCommand(
-            project_id=request.project_id,
+            project_id=project_id,
             library_id=request.library_id,
             name=request.name,
             storage_key=request.storage_key,

apps/api/app/schemas/asset.py

@@ -2,7 +2,7 @@ from pydantic import BaseModel, Field
 
 
 class CreateAssetRequest(BaseModel):
-    project_id: str = Field(..., min_length=1)
+    project_id: str | None = Field(default=None, description="可选，不传时从 library.project_id 自动推导")
     library_id: str = Field(..., min_length=1)
     name: str = Field(..., min_length=1, max_length=100)
     storage_key: str = Field(..., min_length=1, max_length=255)

tests/unit/test_create_asset_optional_project_id.py

@@ -0,0 +1,190 @@
+"""测试 create_asset 端点：project_id 可选，从 library 自动推导。"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+from app.api.routes.assets import create_asset
+from app.auth import AuthenticatedUser
+from app.schemas.asset import CreateAssetRequest
+from fastapi import HTTPException
+
+from packages.domain import AssetStatus, ClassificationStatus
+
+
+@pytest.fixture
+def mock_user():
+    user = MagicMock(spec=AuthenticatedUser)
+    user.user.id = "user-123"
+    return user
+
+
+@pytest.fixture
+def mock_library():
+    lib = MagicMock()
+    lib.id = "lib-abc"
+    lib.project_id = "proj-from-library"
+    return lib
+
+
+@pytest.fixture
+def mock_project():
+    proj = MagicMock()
+    proj.id = "proj-from-library"
+    proj.can_access.return_value = True
+    return proj
+
+
+def _make_request(**overrides):
+    defaults = dict(
+        library_id="lib-abc",
+        name="test-audio.mp3",
+        storage_key="uploads/test.mp3",
+        mime_type="audio/mpeg",
+        file_size=1024,
+        status="uploading",
+    )
+    defaults.update(overrides)
+    return CreateAssetRequest(**defaults)
+
+
+def test_project_id_derived_from_library_when_not_provided(mock_user, mock_library, mock_project):
+    """前端不传 project_id 时，从 library.project_id 自动推导。"""
+    request = _make_request()  # project_id 默认 None
+
+    asset_repo = MagicMock()
+    lib_repo = MagicMock()
+    lib_repo.get.return_value = mock_library
+    proj_repo = MagicMock()
+    proj_repo.find_by_id.return_value = mock_project
+
+    expected_asset = MagicMock()
+    expected_asset.id = "asset-1"
+    expected_asset.project_id = "proj-from-library"
+    expected_asset.library_id = "lib-abc"
+    expected_asset.name = "test-audio.mp3"
+    expected_asset.storage_key = ""
+    expected_asset.mime_type = "audio/mpeg"
+    expected_asset.metadata = {}
+    expected_asset.file_size = 1024
+    expected_asset.thumbnail_url = None
+    expected_asset.duration = None
+    expected_asset.width = None
+    expected_asset.height = None
+    expected_asset.fps = None
+    expected_asset.codec = None
+    expected_asset.status = AssetStatus.UPLOADING
+    expected_asset.classification_status = ClassificationStatus.PENDING
+    expected_asset.quality_score = None
+    expected_asset.created_at = None
+    expected_asset.uploaded_by_user_id = "user-123"
+    expected_asset.tag_ids = []
+    with patch("app.api.routes.assets.CreateAssetUseCase") as mock_uc:
+        mock_uc.return_value.execute.return_value = expected_asset
+        result = create_asset(
+            request=request,
+            authenticated_user=mock_user,
+            asset_repository=asset_repo,
+            asset_library_repository=lib_repo,
+            project_repository=proj_repo,
+        )
+
+    # 验证 project_id 被正确推导
+    proj_repo.find_by_id.assert_called_once_with("proj-from-library")
+    # 验证 use case 使用的是推导出的 project_id
+    cmd = mock_uc.return_value.execute.call_args[0][0]
+    assert cmd.project_id == "proj-from-library"
+
+
+def test_explicit_project_id_used_when_provided(mock_user, mock_library, mock_project):
+    """前端显式传 project_id 时，优先使用请求值。"""
+    mock_project.id = "proj-explicit"
+    mock_project.can_access.return_value = True
+    mock_library.project_id = "proj-explicit"  # 匹配
+
+    request = _make_request(project_id="proj-explicit")
+
+    asset_repo = MagicMock()
+    lib_repo = MagicMock()
+    lib_repo.get.return_value = mock_library
+    proj_repo = MagicMock()
+    proj_repo.find_by_id.return_value = mock_project
+
+    mock_asset = MagicMock()
+    mock_asset.id = "asset-1"
+    mock_asset.storage_key = ""
+    mock_asset.mime_type = "audio/mpeg"
+    mock_asset.project_id = "proj-explicit"
+    mock_asset.library_id = "lib-abc"
+    mock_asset.name = "test"
+    mock_asset.metadata = {}
+    mock_asset.file_size = 0
+    mock_asset.thumbnail_url = None
+    mock_asset.duration = None
+    mock_asset.width = None
+    mock_asset.height = None
+    mock_asset.fps = None
+    mock_asset.codec = None
+    mock_asset.status = AssetStatus.UPLOADING
+    mock_asset.classification_status = ClassificationStatus.PENDING
+    mock_asset.quality_score = None
+    mock_asset.created_at = None
+    mock_asset.uploaded_by_user_id = "user-123"
+    mock_asset.tag_ids = []
+
+    with patch("app.api.routes.assets.CreateAssetUseCase") as mock_uc:
+        mock_uc.return_value.execute.return_value = mock_asset
+        create_asset(
+            request=request,
+            authenticated_user=mock_user,
+            asset_repository=asset_repo,
+            asset_library_repository=lib_repo,
+            project_repository=proj_repo,
+        )
+
+    proj_repo.find_by_id.assert_called_once_with("proj-explicit")
+    cmd = mock_uc.return_value.execute.call_args[0][0]
+    assert cmd.project_id == "proj-explicit"
+
+
+def test_library_not_found_returns_404(mock_user):
+    """素材库不存在时返回 404。"""
+    request = _make_request()
+
+    lib_repo = MagicMock()
+    lib_repo.get.return_value = None
+    proj_repo = MagicMock()
+    asset_repo = MagicMock()
+
+    with pytest.raises(HTTPException) as exc_info:
+        create_asset(
+            request=request,
+            authenticated_user=mock_user,
+            asset_repository=asset_repo,
+            asset_library_repository=lib_repo,
+            project_repository=proj_repo,
+        )
+    assert exc_info.value.status_code == 404
+
+
+def test_library_project_mismatch_returns_400(mock_user, mock_library, mock_project):
+    """当 library.project_id 与请求的 project_id 不一致时返回 400。"""
+    mock_library.project_id = "proj-A"
+    mock_project.id = "proj-B"
+
+    request = _make_request(project_id="proj-B")
+
+    lib_repo = MagicMock()
+    lib_repo.get.return_value = mock_library
+    proj_repo = MagicMock()
+    proj_repo.find_by_id.return_value = mock_project
+    asset_repo = MagicMock()
+
+    with pytest.raises(HTTPException) as exc_info:
+        create_asset(
+            request=request,
+            authenticated_user=mock_user,
+            asset_repository=asset_repo,
+            asset_library_repository=lib_repo,
+            project_repository=proj_repo,
+        )
+    assert exc_info.value.status_code == 400