Get results from write in JVM client?

EventStoreDB
1

Hi,

I'm currently using the JVM client, and do writes like so:

getEventStoreService.getConnection().tell( writeEvents, writeResult );

Where writeResult is the WriteResult class from the examples (minus
shutting it down). This works ok, but I would like to return the
written position that the WriteResult gets from the method that calls
tell.

Question: how much overhead is it to create the WriteResult actors?
Meaning, can I create one WriteResult per call to tell, so that it can
hold a Future to pass in to the onReceive callback? Or are there other
better patterns to achieve synchronous results from the write?

regards, Rickard

2

Hi, I think you need to look into eventstore.j.EsConnection interface and create EsConnectionImpl out of connection actor

3

Hi

Hi, I think you need to look into eventstore.j.EsConnection interface and
create EsConnectionImpl out of connection actor

I would, except that one is buggy with regards to configuration, so
the previous recommendation was to go with SubscriptionObserverActor,
which I am now. Is there any way of doing the same thing with the SOA?

cheers, Rickard

4

Then you can use ask pattern against connection actor - http://doc.akka.io/docs/akka/2.4.1/java/lambda-actors.html#The_Inbox

5

Hey!

Then you can use ask pattern against connection actor -
http://doc.akka.io/docs/akka/2.4.1/java/lambda-actors.html#The_Inbox

Cool! So, here's what the code ended up like:

Future<?> result = ask(connection, message, writeTimeout);
return Await.result( result, Duration.apply(writeTimeout,
TimeUnit.MILLISECONDS) );

Fairly straightforward. With this I can get the commit position out,
and do a redirect in my REST API to a URL that contains that position,
and a request filter that then waits until that position has been
applied in the database. Read-own-writes in an eventual consistency
system. Happy!

cheers, Rickard

6

I feel like there should be an easier way of getting the result of a write. Maybe im misunderstanding but there are many cases where you need rhe result such as writing without expected version and getting the assigned version.

7

Rickard, could you try new version of client, which should fix your configurational issue
http://search.maven.org/#search|ga|1|g%3Acom.geteventstore%20AND%20eventstore-client