我正在尝试使用 FastAPI 中的 PUT 操作更新数据库中的单个记录。但出于某种原因，我不断收到此错误。除了这一项之外，所有其他操作都可以正常工作。该错误仅针对更新查询引发。

AttributeError: 'Blog' object has no attribute 'items'

这是相关的代码。

def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()

class Blog(BaseModel):
    title: str
    body: str

@app.put('/blog/{id}', status_code=status.HTTP_204_NO_CONTENT, response_class=Response)
def update(id: int, request: schemas.Blog, db: Session = Depends(get_db)):
    blog = db.query(models.Blog).filter(models.Blog.id == id)
    if not blog.first():
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND,
                            detail=f'Blog with id {id} not found')
    blog.update(request)
    db.commit()

这是堆栈跟踪：

Traceback (most recent call last):
  File "c:devfast-tutsenvlibsite-packagesuvicornprotocolshttph11_impl.py", line 396, in run_asgi        
    result = await app(self.scope, self.receive, self.send)
  File "c:devfast-tutsenvlibsite-packagesuvicornmiddlewareproxy_headers.py", line 45, in __call__        
    return await self.app(scope, receive, send)
  File "c:devfast-tutsenvlibsite-packagesfastapiapplications.py", line 199, in __call__
    await super().__call__(scope, receive, send)
  File "c:devfast-tutsenvlibsite-packagesstarletteapplications.py", line 111, in __call__
    await self.middleware_stack(scope, receive, send)
  File "c:devfast-tutsenvlibsite-packagesstarlettemiddlewareerrors.py", line 181, in __call__
    raise exc from None
  File "c:devfast-tutsenvlibsite-packagesstarlettemiddlewareerrors.py", line 159, in __call__
    await self.app(scope, receive, _send)
  File "c:devfast-tutsenvlibsite-packagesstarletteexceptions.py", line 82, in __call__
    raise exc from None
  File "c:devfast-tutsenvlibsite-packagesstarletteexceptions.py", line 71, in __call__
    await self.app(scope, receive, sender)
  File "c:devfast-tutsenvlibsite-packagesstarletterouting.py", line 566, in __call__
    await route.handle(scope, receive, send)
  File "c:devfast-tutsenvlibsite-packagesstarletterouting.py", line 227, in handle
    await self.app(scope, receive, send)
  File "c:devfast-tutsenvlibsite-packagesstarletterouting.py", line 41, in app
    response = await func(request)
  File "c:devfast-tutsenvlibsite-packagesfastapirouting.py", line 201, in app
    raw_response = await run_endpoint_function(
  File "c:devfast-tutsenvlibsite-packagesfastapirouting.py", line 150, in run_endpoint_function
    return await run_in_threadpool(dependant.call, **values)
  File "c:devfast-tutsenvlibsite-packagesstarletteconcurrency.py", line 34, in run_in_threadpool
    return await loop.run_in_executor(None, func, *args)
  File "C:Python39libconcurrentfuturesthread.py", line 52, in run
    result = self.fn(*self.args, **self.kwargs)
  File ".blogmain.py", line 66, in update
    blog.update(request)
  File "c:devfast-tutsenvlibsite-packagessqlalchemyormquery.py", line 3190, in update
    upd = upd.values(values)
  File "<string>", line 2, in values
  File "c:devfast-tutsenvlibsite-packagessqlalchemysqlbase.py", line 96, in _generative
    x = fn(self, *args, **kw)
  File "<string>", line 2, in values
  File "c:devfast-tutsenvlibsite-packagessqlalchemysqlbase.py", line 125, in check
    return fn(self, *args, **kw)
  File "c:devfast-tutsenvlibsite-packagessqlalchemysqldml.py", line 701, in values
    for k, v in arg.items()
AttributeError: 'Blog' object has no attribute 'items'

回答

blog.update({'title': request.title, 'body': request.body})

blog.update(request.dict())