Add Async method to SchemaBuilder to prevent possible thread starvation

[MikeAlhayek]

Fix #509

Note, there was a bug in the dispose logic of the Session class. The method CommitOrRollbackTransactionAsync has slightly different logic than CommitOrRollbackTransaction. I believe the logic in CommitOrRollbackTransaction is better and used.

[sebastienros]

Unit tests are failing since adding Rollabck in the DbGenerator, only on Sql, maybe the connection is already disposing the transaction. We need to understand what is happening. I am not sure we should just remove it since it's working for other databases. But that's a safety net.

[sebastienros]

Are you getting lazy, or just bored?

[MikeAlhayek]

Are you getting lazy, or just bored?

I wish I was board and have nothing else better to do.

[MikeAlhayek]

@sebastienros I think all the issues are now fixed.

• After modifying the CommitOrRollbackTransactionAsync logic, await using var session = ... works as expected and all tests now await and pass.
• In the DbBlockIdGenerator, I added the RollbackAsync() call you requested and it now worked. To get that to work, for some reason I had to set throwOnError to true when initializing SchemaBuilder instance.
• I also changed all the BeginTransaction calls to BegingTransactonAsync

Now, everything support async which is great! Let me know if you see anything else or if you good with merging this one.

[jtkech]

@sebastienros

Don't remember the details around this but are you sure about using ConfigureAwait(false) before GetAwaiter()?

[MikeAlhayek]

I think it just handles the error differently.

Do you see an issue?

[jtkech]

Would need more time to remember the details so not sure but reading again https://blog.stephencleary.com/2012/07/dont-block-on-async-code.html

For example this and that

Using ConfigureAwait(false) to avoid deadlocks is a dangerous practice.

The top-level methods, meanwhile, do require the context, so they cannot use ConfigureAwait(false)

I would not have used .ConfigureAwait(false) here but inside CommitOrRollbackTransactionAsync(), applied on the async call that it does.

Which may be useless if it is called asynchronously but maybe better for this synchronous usage.

But not sure ;)

[jtkech]

In the doubt I would not have used it at all.

[MikeAlhayek]

Okay. I'll remove it tomorrow before releasing the new version

[MikeAlhayek]

@jtkech what about in the other places like Session.Save and the SchemeBuilder?

[jtkech]

Idem for me.

Otherwise we may need to use it on each async call everywhere.

[MikeAlhayek]

Just to confirm, you suggest removing .ConfigureAwait(false) everywhere it's used? So .GetAwaiter().GetResult() only?

[jtkech]

Yes for now

[MikeAlhayek]

@jtkech done via #511

Let me know if you need anything else modified