@knorrus the major problem with the default serializer is that it may (and will be) changed in the future, while your persisted events format won't. You can always use your own serializer - depending on who you'll ask, there will be different responses. My favourite are schema-defined ones, like proto buf, flat buffers or MS Bond
@cduhard it's still better to do so asynchronously
i suppose I could start a timer when the Coordinator receives the Shutdown which is what the silly thread.sleep us trying to accomplish
Become(ShuttingDown) -> fire up timer, handle the timer message -> check for PersistentActors status, then shutdown remaining worker children
@to11mtm in general you should never allow third party library tell you what format it will use to store your data. What if something changes or you'll need to migrate your data to another solution? You should either specify message format by yourself or have some migration path for it - if I'm right after 1.5 we'll switch to Wire, but still you'll be able to use json.net serializer as an alternative, you'll just need to specify it explicitly. Also we'll probably provide some tips about how to write format migration scenarios.
i can't complete the shutdown until they are all passivated
an external shutdown gets triggered, Coordinator receives and waits for passivation of all PA children. once they are all terminated shutdown of supporting worker children can commence
its the waiting part that requires the timer
i can't use a poisonpill because I can't shutdown a PA that way
there are non-persistent sagas in progress
so i can just wait for all to passivate
if I had your cool persistent sagas in your new cluster sharding sample app, I could just poisonpill the lot and move on
I don't need to build that because I can just wait for them to passivate. there are no new messages coming in. the shutdown has cut that off further up the hierarchy
so i can move forward
a timer is just as easy as trying to keep track of what's alive etc
not as precise, but far less complex
if i were to cluster & shard this I would do this in a more robust way
am I making sense?
i need to know when all of them are terminated
i can't do anything until that happems
*happens
they terminate without the app being in shutdown
...
// normal receive
message.Match()
.With<Shutdown>(shutdown =>{
var accounts = Context.GetChildren().Select(aref => aref.Path.Name.Contains("account")).ToArray();
foreach(var account in accounts) account.Tell(shutdown);
Become(WaitingForTermination(accounts.Length))
});
}
public Receive WaitingForTermination(int counter) {
var remaining = counter;
return message => message.Match()
.With<Terminated>(terminated => {
if(terminated.ActorRef.Path.Name.Contains("account"))
remaining--;
if(remaining == 0)
AllAccountsTerminated();
})
.WasHandled;
}
@Horusiath thanks a lot though. I am the only one doing message based work here, I have no one to bounce this stuff off of
j/k ;)
@Horusiath regarding your sharding persistence app, the intention is for you sagas to continue on restart correct?