google.appengine.api.datastore.Transactional

A decorator that makes sure a function is run in a transaction.

google.appengine.api.datastore.Transactional(
    _func=None, **kwargs
)

Defaults propagation to datastore_rpc.TransactionOptions.ALLOWED, which means any existing transaction will be used in place of creating a new one.

WARNING: Reading from the datastore while in a transaction will not see any changes made in the same transaction. If the function being decorated relies on seeing all changes made in the calling scoope, set propagation=datastore_rpc.TransactionOptions.NESTED.

Args
_func	do not use.
**kwargs	TransactionOptions configuration options.

Returns
A wrapper for the given function that creates a new transaction if needed.