Transaction support for MongoDB with Panache

[loicmathieu]

Fixes #11294

[loicmathieu]

@FroMage I made this new prototype for Transaction support for MongoDB with Panache with some adjustements based on your feedbacks on #10097 (comment)

@loicmathieu we could perhaps skip supporting the reactive ones at first, and offer an equivalent to the transactional API that we have for HR+Panache. As for the initialisation of the client in the interceptor, I think you should be able to skip the interceptor entirely and delay the bit which registers your client to the TM until it's used. I'm pretty sure ORM does it this way: when you call an operation (not just obtain a client) we look at whether we have a current JTA transaction and if yes, we create a mongo transaction and register it to the TM (the same part you currently do in the interceptor).

So now, I don't use a CDI interceptor and I create the session when needed.

I need to re-implement everything as due to the changes for Kotlin support, my old branch cannot be rebased, as it'll take some time I want to be sure that this is the good direction before going on so I just implement one method to show you how it will be used.

If you validate the design, I'll report all the changes from my old branch.

With this design, I'll still need to find a way to pass the transaction options from the calling method (to be discussed later).

[FroMage]

Sorry it took such a long time. This looks just fine to me :)

[loicmathieu]

OK great !
I'll finish the implementation and we can discuss it more

[loicmathieu]

@gytis I implemented transaction support for MongoDB with Panache and it crashed the integration test of rest data support for MongoDB with Panache.

Apparently, you add the @Transactional annotation even for MongoDB, perviously it has no effect, now it uses a transaction so if the user didn't use a replicat set (and a version that support transaction) it failed.

I think the best would be to disabled transaction for MongoDB via Rest Data Panache, I'm not sure how to do this.

[evanchooly]

Just had the one question about that exception but otherwise looks nice.

[FroMage]

LGTM, but you may want to add the following methods?

public class Panache {

     /**
     * Returns the current {@link TransactionManager}
     *
     * @return the current {@link TransactionManager}
     */
    public static TransactionManager getTransactionManager() {
        return AbstractJpaOperations.getTransactionManager();
    }

   /**
     * Marks the current transaction as "rollback-only", which means that it will not be
     * committed: it will be rolled back at the end of this transaction lifecycle.
     */
    public static void setRollbackOnly() {
        AbstractJpaOperations.setRollbackOnly();
    }

}

I'm not sure if TransactionManager is visible in Mongo, now that you depend on narayana.

[loicmathieu]

@FroMage there is no global Panache helper class on MongoDB with Panache and I'm reluctant to add one to only provide a shorter path for this. One can simply inject the TransactionManager if he want to do it.

[FroMage]

@FroMage there is no global Panache helper class on MongoDB with Panache and I'm reluctant to add one to only provide a shorter path for this. One can simply inject the TransactionManager if he want to do it.

Oh, I didn't know.

[loicmathieu]

@gytis can you have a look at the following commit: 20edd61

I manage to make the REST data impl working for both Hibernate and Mongo by allowing to use a different update operator to avoid having a transaction for MongoDB.

@FroMage if you know this part, maybe you can also have a look at it.

[gytis]

@loicmathieu sorry for a delay. I was on PTO since the middle of the last week.
I wasn't aware of this MongoDB transaction effort, I would have taken it into account when adding the transactional executor. I only added it a couple of weeks ago. In any case, I think your fix looks good.

[loicmathieu]

@gytis thanks for looking at it

@loicmathieu sorry for a delay. I was on PTO since the middle of the last week.

No problem for the delay, it gives me the opportunity to have a look at the impl of rest data and it's an interesting piece of code ;)