EnlistInAmbientTransaction should not change isolation level to SERIALIZABLE if there is no ambient transaction #12

Activity

1. fschmied commented on Mar 23, 2016

   

   fschmied

   on Mar 23, 2016

   Author

   More actions

   Workaround for 5.2.0: Ensure there is an active TransactionScope with ReadCommitted isolation level whenever an NEventStore API is called and EnlistInAmbientTransaction is turned on.
2. HAXEN commented on May 11, 2016

   

   HAXEN

   on May 11, 2016

   More actions

   @fschmied Could you provide a simple code example of how this should be done? For me as a novice to understand.
3. fschmied commented on May 30, 2016

   

   fschmied

   on May 30, 2016

   Author

   More actions

   @HAXEN Sorry, I missed your question. First, check if you really need EnlistInAmbientTransaction, many CQRS applications will not need this option. If you do, wrap all your calls to IStoreEvents in blocks such as this one:

   using (var tx = new TransactionScope (TransactionScopeOption.Required, IsolationLevel.ReadCommitted))
   {
     var stream = _eventStore.OpenStream(bucketId, streamId, fromRevision, int.MaxValue);
     tx.Complete();
     return stream;
   }
   
4. fschmied commented on May 30, 2016

   

   fschmied

   on May 30, 2016

   Author

   More actions

   (PS: IPersistStreams might also be affected, you'll need to check this yourself.)
5. HAXEN commented on May 30, 2016

   

   HAXEN

   on May 30, 2016

   More actions

   My usecase being:

   Let's say I have an AggregateRoot representing a country and the key being
   'sv' for sweden and 'fr' for france etc...

   In order to not having duplicates into the eventstore I figure either
   having the streamId = 'sv' and query that before creating a new, or having
   a table languages with a primary key on countrycode.

   Or

   Should I make the system being able to create duplicates and in that case
   having the read side "delete" the duplicate with a command? In this case
   how is this usually handled regarding feedback to the user?

   Being sort of new to CQRS this is not clear to me.

   On Mon, May 30, 2016 at 4:47 PM, Fabian Schmied notifications@github.com
   wrote:

   (PS: IPersistStreams might also be affected, you'll need to check this
   yourself.)

   —
   You are receiving this because you were mentioned.
   Reply to this email directly, view it on GitHub
   #12 (comment),
   or mute the thread
   https://github.com/notifications/unsubscribe/AAJZ1nXVIHqtk4JqiNeG1bUfrQu2FTe0ks5qGviLgaJpZM4FvBfm
   .
6. fschmied commented on Jun 2, 2016

   

   fschmied

   on Jun 2, 2016

   Last edited by fschmied

   Author

   More actions

   @HAXEN I guess this bug report is not the right way to discuss your specific question, better ask at https://groups.google.com/d/forum/dddcqrs for CQRS-speciifc questions or at https://groups.google.com/forum/#!forum/neventstore for NEventStore-related ones.

   That said, the OpenStream API in NEventStore allows you to specify "0" as the "minimum revision" when opening a stream. This will create the stream if it doesn't exist, or read it if it does. You can then check whether the StreamRevision is 0. If it is, the stream has just been newly created. If not, it already existed. This should make it quite easy to prevent duplicates based on the stream ID.
7. AGiorgetti commented on Apr 8, 2017

   

   AGiorgetti

   on Apr 8, 2017

   Last edited by AGiorgetti

   Member

   More actions

   If there's no ambiente transaction an 'EnlistInAmbientTransaction' has been called a new TransactionScope with the default ReadCommitted transaction isolation level will be generated
8. AGiorgetti

   added a commit that references this issue on Apr 8, 2017

   Fix: #12

   This issue will close once commit 6a0f9ee is merged into the 'develop' branch.

   6a0f9ee
9. AGiorgetti

   closed this as completedon Apr 8, 2017
10. AGiorgetti

    added this to the v6.0.0 milestone on Apr 8, 2017