关于#python#的问题，如何解决？

Question

麻烦问一下各位， 下面这段代码中报错如下
代码部分

app.route('/deleteaccount/<int:account_id>', methods=['POST'])
@login_required
def delete_account(account_id) :
    authed = session.get('authed')
    if not authed :
        return redirect(url_for('login'))
    form1 = DeleteAccountForm()
    account = User.query.get_or_404(account_id)
    if form1.submit.data and form1.validate() :
        if current_user.id != account.id :
            abort(401)
            flash('Usurpation')
        logout_user()
        db.session.delete(account)
        db.session.commit()
        session.pop('authed')
        flash('Disposed')
    else :
        abort(400)
    return redirect(url_for('login'))



@db.event.listens_for(User, 'after_delete', named=True)
def edit_account(**kwargs) :
    target = kwargs['target']
    for username in [target.username] :
        if username is not None :
            dis = Photo.query.filter_by(user_name=username).delete()
            db.session.begin(subtransactions=True)
            db.session.commit()

报错

    File "/usr/local/lib/python3.10/dist-packages/flask_socketio/__init__.py", line 43, in __call__

    return super(_SocketIOMiddleware, self).__call__(environ,

    File "/usr/local/lib/python3.10/dist-packages/engineio/middleware.py", line 74, in __call__

    return self.wsgi_app(environ, start_response)

    File "/usr/local/lib/python3.10/dist-packages/flask/app.py", line 2193, in wsgi_app

    response = self.handle_exception(e)

    File "/usr/local/lib/python3.10/dist-packages/flask/app.py", line 2190, in wsgi_app

    response = self.full_dispatch_request()

    File "/usr/local/lib/python3.10/dist-packages/flask/app.py", line 1486, in full_dispatch_request

    rv = self.handle_user_exception(e)

    File "/usr/local/lib/python3.10/dist-packages/flask/app.py", line 1484, in full_dispatch_request

    rv = self.dispatch_request()

    File "/usr/local/lib/python3.10/dist-packages/flask/app.py", line 1469, in dispatch_request

    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)

    File "/usr/local/lib/python3.10/dist-packages/flask_login/utils.py", line 290, in decorated_view

    return current_app.ensure_sync(func)(*args, **kwargs)

    File "/var/www/html/albumy2/app.py", line 626, in delete_account

                    if current_user.id != account.id :

                            abort(401)

                            flash('Usurpation')

                    logout_user()

                    db.session.delete(account)

                    db.session.commit()

                    session.pop('authed')

                    flash('Disposed')

            else :

                    abort(400)

            return redirect(url_for('login'))

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/scoping.py", line 553, in commit

    return self._proxied.commit()

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 1906, in commit

    trans.commit(_to_root=True)

    File "<string>", line 2, in commit
    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/state_changes.py", line 137, in _go

    ret_value = fn(self, *arg, **kw)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 1221, in commit

    self._prepare_impl()

    File "<string>", line 2, in _prepare_impl
    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/state_changes.py", line 137, in _go

    ret_value = fn(self, *arg, **kw)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 1196, in _prepare_impl

    self.session.flush()

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 4154, in flush

    self._flush(objects)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 4290, in _flush

    with util.safe_reraise():

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/util/langhelpers.py", line 147, in __exit__

    raise exc_value.with_traceback(exc_tb)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 4251, in _flush

    flush_context.execute()

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/unitofwork.py", line 467, in execute

    rec.execute(self)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/unitofwork.py", line 681, in execute

    util.preloaded.orm_persistence.delete_obj(

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/persistence.py", line 206, in delete_obj

    mapper.dispatch.after_delete(mapper, connection, state)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/event/attr.py", line 487, in __call__

    fn(*args, **kw)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/events.py", line 887, in wrap

    fn(*arg, **kw)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/event/attr.py", line 174, in wrap_kw

    return fn(**argdict)

    File "/var/www/html/albumy2/app.py", line 870, in edit_account

    db.session.begin(subtransactions=True)

    TypeError: scoped_session.begin() got an unexpected keyword argument 'subtransactions'

但当我删去db.session.begin(subtransactions=True) 时 报错如下

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 4251, in _flush

    flush_context.execute()

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/unitofwork.py", line 467, in execute

    rec.execute(self)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/unitofwork.py", line 681, in execute

    util.preloaded.orm_persistence.delete_obj(

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/persistence.py", line 206, in delete_obj

    mapper.dispatch.after_delete(mapper, connection, state)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/event/attr.py", line 487, in __call__

    fn(*args, **kw)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/events.py", line 887, in wrap

    fn(*arg, **kw)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/event/attr.py", line 174, in wrap_kw

    return fn(**argdict)

    File "/var/www/html/albumy2/app.py", line 871, in edit_account

    db.session.commit()

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/scoping.py", line 553, in commit

    return self._proxied.commit()

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 1906, in commit

    trans.commit(_to_root=True)

    File "<string>", line 2, in commit
    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/state_changes.py", line 137, in _go

    ret_value = fn(self, *arg, **kw)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 1239, in commit

    self._parent.commit(_to_root=True)

    File "<string>", line 2, in commit
    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/state_changes.py", line 121, in _go

    raise sa_exc.IllegalStateChangeError(

    During handling of the above exception, another exception occurred:
    File "/usr/local/lib/python3.10/dist-packages/flask_socketio/__init__.py", line 43, in __call__

    return super(_SocketIOMiddleware, self).__call__(environ,

    File "/usr/local/lib/python3.10/dist-packages/engineio/middleware.py", line 74, in __call__

    return self.wsgi_app(environ, start_response)

    File "/usr/local/lib/python3.10/dist-packages/flask/app.py", line 2193, in wsgi_app

    response = self.handle_exception(e)

    File "/usr/local/lib/python3.10/dist-packages/flask/app.py", line 2190, in wsgi_app

    response = self.full_dispatch_request()

    File "/usr/local/lib/python3.10/dist-packages/flask/app.py", line 1486, in full_dispatch_request

    rv = self.handle_user_exception(e)

    File "/usr/local/lib/python3.10/dist-packages/flask/app.py", line 1484, in full_dispatch_request

    rv = self.dispatch_request()

    File "/usr/local/lib/python3.10/dist-packages/flask/app.py", line 1469, in dispatch_request

    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)

    File "/usr/local/lib/python3.10/dist-packages/flask_login/utils.py", line 290, in decorated_view

    return current_app.ensure_sync(func)(*args, **kwargs)

    File "/var/www/html/albumy2/app.py", line 626, in delete_account

    db.session.commit()

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/scoping.py", line 553, in commit

    return self._proxied.commit()

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 1906, in commit

    trans.commit(_to_root=True)

    File "<string>", line 2, in commit
    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/state_changes.py", line 137, in _go

    ret_value = fn(self, *arg, **kw)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 1221, in commit

    self._prepare_impl()

    File "<string>", line 2, in _prepare_impl
    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/state_changes.py", line 137, in _go

    ret_value = fn(self, *arg, **kw)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 1196, in _prepare_impl

    self.session.flush()

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 4154, in flush

    self._flush(objects)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 4290, in _flush

    with util.safe_reraise():

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/util/langhelpers.py", line 151, in __exit__

    raise value.with_traceback(traceback)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 4291, in _flush

    transaction.rollback(_capture_exception=True)

    File "<string>", line 2, in rollback
    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/state_changes.py", line 103, in _go

    self._raise_for_prerequisite_state(fn.__name__, current_state)

    File "/usr/local/lib/python3.10/dist-packages/sqlalchemy/orm/session.py", line 921, in _raise_for_prerequisite_state

    raise sa_exc.ResourceClosedError("This transaction is closed")

    sqlalchemy.exc.ResourceClosedError: This transaction is closed

Answer 1

抱歉，您并没有提供具体的错误信息，我无法确定您所遇到的报错是什么。不过，可以根据代码片段中的问题点来做一些可能需要解决的问题。

首先，在 delete_account 视图函数中，存在如下问题：

1.abort(400) 的使用不当：在表单验证失败时，应该返回错误信息而不是直接 Abort 请求。

2.在删除账户后，使用 logout_user() 和 session.pop('authed') 使得当前用户退出登录，但是这样做会导致一个问题，即在额外发送一个请求登录同一帐户时，会看到旧用户数据闪现一下然后被踢出。因此，建议使用 Flask-Login 提供的 logout_user() 函数来注销当前用户，并删除 authed 会话变量。

3.在删除账户之前，应该判断当前用户是否拥有操作权限，否则应该返回 401 错误。

其次，在 edit_account 监听器函数中，存在如下问题：

1.使用 db.session.begin(subtransactions=True) 开始子事务后，却未使用 db.session.commit() 结束子事务。如果多次调用 begin() 而未结束子事务，则会导致数据库锁定并最终崩溃。因此，建议在每次调用 begin() 之后调用 commit() 来结束子事务。

2.没有使用 with db.session.no_autoflush: 上下文管理器，将会导致出现一些危险的行为，如在写入数据库之前调用 db.session.flush()。因此，建议使用 with db.session.no_autoflush: 来确保代码安全。

希望这些信息能够对您有所帮助。如果您需要进一步的帮助，请您提供更多详细信息。