Distributed transactions are not supported

[KristinXie1]

[ActiveIssue("Distributed transactions are not supported.")]

Test methods:
Vol0_Dur1_2PC()
Vol0_Dur2()
under: corefx\src\System.Transactions\tests\EnlistTest.cs

Details:
https://github.com/dotnet/corefx/blob/master/src/System.Transactions.Local/tests/EnlistTest.cs#L145
https://github.com/dotnet/corefx/blob/master/src/System.Transactions.Local/tests/EnlistTest.cs#L450

[danmoseley]

Known limitation - since we have some tests there, they are disabled against this tracking issue for potential future support.

[danmoseley]

Alternatively the tests can be deleted. I imagine if we added this feature we'd need more than 2 tests :)

[stephentoub]

Already have https://github.com/dotnet/corefx/issues/13532 as well tracking this

[dmetzgar]

Duplicate of #17937

[karelz]

@dmetzgar did you update the tests to point to the new issue? If not, please reopen and make the change prior to closing -- otherwise our vendors will reopen it again in next sweep.

[dmetzgar]

@karelz no I didn't realize they made a code change
@qizhanMS could you make that change?

[karelz]

@dmetzgar FYI: it's the 'disabled-test' label which tracks that. I said it also in the offline email that it may be easier just to dupe the old issue against this one ...

[qizhanMS]

@karelz I got confused on which issue number we should use in the code. Please specify. Also should we close some issues because dotnet/corefx#16755, #19318 and #17937 are same root cause.

[karelz]

If you have duplicates, mark as as duplicates and close them.
The issue which is used in ActiveIssue on disabled tests has to be open. It is up to you if you want to go and update the attributes on tests, or make you life easier and keep open the issue which is disabled from ActiveIssue in tests.
Does it help?

Overall: No process, just common sense ;)

[qizhanMS]

We now may have trouble because I updated the code and changed 16755 to 13532. Right now, should I change the code back to 16755, or add "disabled-test" label to 13532?

[karelz]

I am lost what is what now.

Here are the rules of common sense:

1. Don't keep multiple issues tracking the same thing, resolve them as duplicates.
2. If a test is disabled (via ActiveIssue), the issue should be opened, not closed.

Does it help?

[evil-shrike]

Apart from problems of issue tracking what are your plans for distributed tx support (System.Transactions) in netcore?

btw this issue is linked from https://github.com/dotnet/corefx/wiki/ApiCompat#systemtransactions

[qizhanMS]

Our team don’t have plan to support distributed tx in netcore in near future. [EDIT] Remove previous email reply by @karelz

[dmetzgar]

Distributed transaction support in Sys.Tx in the Framework depends on MSDTC. There is no equivalent transaction coordinator on other platforms. We left room in Core to create assemblies such as System.Transactions.Msdtc or System.Transactions.ElasticTransactions (for example) so that a transaction coordinator could be plugged in and a transaction could be promoted to use the available coordinator. No plans yet to build a MSDTC plugin since we haven't seen much demand.

[Hviid]

I think this is fair, even though it would be nice.
But I find it hard to find any good guidance on of how to implement exactly-once behavior, when not being able to use DTC.
Does MS have any official guidance, maybe some kind of architecture guidance?
Would be nice if the EF Core docs refered to it:
https://docs.microsoft.com/en-us/ef/core/saving/transactions#limitations-of-systemtransactions

[StephenBonikowsky]

Closing, the tests remain disabled and can be enabled if distributed transactions become supported in Core.