transactions.py 文件源码

def begin(self, request=None):
        """Return new request specific transaction

        :param request: current request

        """
        if request is None:
            request = get_current_request()

        user = get_authenticated_user_id(request)
        txn = getattr(request, '_txn', None)
        if txn is not None:
            txn.abort()
        txn = request._txn = transaction.Transaction(self._synchs, self)
        if user is not None:
            txn.user = user
        _new_transaction(txn, self._synchs)
        request._txn_time = time.time()

        return txn

    # with