trx.commit() does not throw error when commit fails

Environment

Knex version: 0.21.1 Database + version: PostgreSQL 12.2 OS: Ubuntu 18.04

Bug

When calling the commit() method on a transaction and the transaction fails because it was timed out by PostgreSQL through the idle_in_transaction_session_timeout setting, then no exception is thrown. Instead, the commit() method just returns undefined instead of an object.

Here’s a code example that shows the issue:

const sleep = async (ms) => new Promise((res) => setTimeout(() => res(), ms));

(async () => {
  // Set `idle_in_transaction_session_timeout` to 1000 ms.
  // Postgres will kill any transactions that are idle for longer than 1000 ms.
  await knex.raw('set idle_in_transaction_session_timeout to 1000;');

  // Create the transaction.
  const trx = await knex.transaction();

  // Execute any queries, doesn't really matter.
  const updated = await trx('users')
    .where('id', 1)
    .update({
      username: 'test1',
    });

  // We have to wait longer than 1000 ms for
  // `idle_in_transaction_session_timeout` to take effect.
  await sleep(1500);

  // Commit the transaction.
  // This will not throw an error. Instead, it will just return `undefined`.
  const commit = await trx.commit();

  // `isCompleted` also returns `true`,
  // even though the transaction was not really committed.
  const isCompleted = trx.isCompleted();

  // Get the previously updated row from the database to verify
  // that the transaction was not committed.
  const result = await knex('users').where('id', 1);

  console.log({
    updated,
    commit,
    result,
    isCompleted,
  });
})();

[elhigu]

try {
  trx.commit(); // no need to await this since trx.executionPromise will wait it to finish anyways
  await trx. executionPromise;
  // transaction was success
} catch (err) {
  // transaction failed / was rolled back
}

[chescos]

Thanks, guys! That helps a lot. I have missed that while reading the docs.