Transaction support in Loopback4?

问题

How to support transaction in Loopback4? Is there a decorator for the same, something like @Transaction?

I looked into the documentation here https://loopback.io/doc/en/lb4/Repositories.html but nothing is mentioned about the transaction.

回答1:

LoopBack 4 does not support transactions out of the box. Please open a new GitHub issue to discuss how to implement this feature:

https://github.com/strongloop/loopback-next/issues/new

回答2:

LoopBack 4 now supports database transactions for quite a while:

import {
  Transaction,
  DefaultTransactionalRepository,
  IsolationLevel,
} from '@loopback/repository';

// assuming there is a Note model extending Entity class, and
// ds datasource which is backed by a transaction enabled
// connector
const repo = new DefaultTransactionalRepository(Note, ds);
// Now we have a transaction (tx)
const tx = await repo.beginTransaction(IsolationLevel.READ_COMMITTED);

const created = await repo.create({title: 'Groceries'}, {transaction: tx});
const updated = await repo.update(
  {title: 'Errands', id: created.id},
  {transaction: tx},
);

// commit the transaction to persist the changes
await tx.commit();