TransactionTimedOutException during DefaultLockRepository.acquire()

[astrubel]

Hi,
I'm facing to TransactionTimedOutException that occurs at DefaultLockRepository.acquire(). I think is the parameter timeout = 1 on the @Transactional annotation on it.
Why the lock is not retried in this case ? It's a naive question, really.
Thank you in advance!

[artembilan]

I think you are right: we need to add a TransactionTimedOutException into this catch:

catch (TransientDataAccessException e) {
					// try again
}

[astrubel]

I will create a pull request for it.
Could you backport to 4.3.x too ?

[artembilan]

Could you backport to 4.3.x too ?

Marked respectively.
Will backport after the Pull Request.

Thanks

[astrubel]

What does represent the parameter timeout on the @Transaction annotation? Is it contains the access time to the database or only the transaction opening and processing time?

[artembilan]

Not sure what is your concern on the matter, but see its JavaDocs:

/**
	 * The timeout for this transaction (in seconds).
	 * <p>Defaults to the default timeout of the underlying transaction system.
	 * <p>Exclusively designed for use with {@link Propagation#REQUIRED} or
	 * {@link Propagation#REQUIRES_NEW} since it only applies to newly started
	 * transactions.
	 * @return the timeout in seconds
	 * @see org.springframework.transaction.interceptor.TransactionAttribute#getTimeout()
	 */
	int timeout() default TransactionDefinition.TIMEOUT_DEFAULT;

So, therefore it a timeout for the whole call including Java and DB access.

[astrubel]

So I think that 1s is not enough for db access through particular networks.

How can we expose this parameter to setup into project side?

Is it possible to replace @Transactional annotation by TransactionTemplate into DefaultLockRepository.acquire() and setup TransactionTemplate.timeout?

@Override
public boolean acquire(String lock) {
   // save previous transactionTemplate values
   int prevIso = transactionTemplate.getIsolationLevel();
   int prevTimeout = transactionTemplate.getTimeout();

   // setup acquire transaction
   transactionTemplate.setIsolationLevel(Isolation.SERIALIZABLE);
   transactionTemplate.setTimeout(this.getTimeout());
   transactionTemplate.execute(st -> {
      deleteExpired(lock);
      if (this.template.update(this.updateQuery, new Date(), this.region, lock, this.id) > 0) {
         return true;
      }
      try {
         return this.template.update(this.insertQuery, this.region, lock, this.id, new Date()) > 0;
      }
      catch (DuplicateKeyException e) {
         return false;
      }
   });

   // restore previous transactionTemplate values
   transactionTemplate.setIsolationLevel(prevIso);
   transactionTemplate.setTimeout(prevTimeout);
}

[artembilan]

I think the best and simplest way is to extend a DefaultLockRepository and override its acquire() with your own @Transactional.
But I see your point and really tended to remove that timeout altogether. No need to be so restrictive. Let's just rely on the underlying transaction management as it is explained on that timeout() option!

Feel free to do such a change in your current PR - and we'll review & merger it shortly.

Thanks

[astrubel]

The current PR concern the management of the timeout exception. So I don't need to modify this one.

You are true, for a particular case the simplest way is to extend and override!

Thank you so much for this talk ;)

[artembilan]

Cherry-picked to 5.3.x & 5.2.x.
Back-port to 4.3.x as b4d9831

@astrubel ,

Thank you for contribution; looking forward for more!

[astrubel]

@artembilan Thank you very much