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Transaction hooks

Register callbacks from inside a @Transactional() method (or TransactionHost#withTransaction) that fire after the transaction settles, via the runOnTransactionCommit / runOnTransactionRollback / runOnTransactionComplete API:

import { runOnTransactionCommit, runOnTransactionRollback, Transactional } from '@nestjs-transactions/typeorm';

@Transactional()
async register(name: string) {
  const member = await this.repo.save({ name });
  runOnTransactionCommit(() => this.mailer.sendWelcome(member)); // only after COMMIT
  runOnTransactionRollback((err) => this.metrics.registrationFailed(err));
  return member;
}
  • Hooks attach to the innermost active transaction: a REQUIRES_NEW or NESTED block's hooks fire on its own outcome; a REQUIRED-joined method's hooks fire with the outer transaction.
  • Async hooks are awaited sequentially (in registration order) before the transactional method's promise settles; commit hooks run on the base connection (the transaction has already committed), so repository calls inside them work.
  • A throwing hook is caught and logged — it never masks the method's own result, and the remaining hooks still run. runOnTransactionComplete receives the rollback error, or undefined on commit.
  • Registering a hook outside an active transaction (including inside a suspended NOT_SUPPORTED/NEVER scope) throws.