StreamPosition Start

[ekjuanrejon]

Hello Guys

I have the following lines. The problem is that the first event from the stream is ignored. checkpointValue can be null. I thought StreamPosition.Start would have done the job. I am using .net grpc client

 var checkpointValue = await GetCheckpoint(_streamName);

 var streamPosition = checkpointValue.HasValue ? StreamPosition.FromInt64(checkpointValue.GetValueOrDefault()) : StreamPosition.Start;

[steven.blair]

Maybe this will help:

Missing first event in catchup subscription

When you pass StreamPosition.Start into a subscription, you’re telling it that the last event you saw (and recorded the event number of) was 0, therefore it starts at 1. There’s a new constant for this in v3 of the API named StreamCheckpoint.StreamStart (since you’re on 2.0.2, you can use null here instead - it’s the same thing). That means you have’t seen anything yet (your checkpoint has no value), so you’ll get events from the start. I’ll try to write some docs around this today. James

[ekjuanrejon]

@steven.blair

Thanks. I came across that blog post but I think it is an old one That uses a different nupkg.

I am using
EventStore.Client.Grpc.Streams

@alexey.zimarev any ideas

[alexey.zimarev]

What exactly are you doing, reading or subscribing? Reads should work fine.

[ekjuanrejon]

I am subscribing to a catch up subscription. So start reading I try to get the existing position. If there is no existing position then I use StreamPosition.Start;

[alexey.zimarev]

I guess you aren’t subscribing to all, are you?

[ekjuanrejon]

I am subscribing because the 2 event does appear in the Stream… Just the first one does not appear

[alexey.zimarev]

Ok, reformulating:

Are you subscribing to $all stream or to a normal stream, or to a projection stream?

[ekjuanrejon]

I am subscribing to a projection… $ce-Customers

[Joao_Braganca]

If you have no checkpoint (i.e. when you are starting out) use the overload that doesn’t take a StreamPosition. e.g.,

var subscription = !checkpoint.HasValue 
  ? await client.SubscribeToStream(_streamName, EventAppeared)
  : await client.SubscribeToStream(_streamName, new StreamPosition((ulong)checkpoint.Value), EventAppeared);

[alexey.zimarev]

Reference: https://github.com/Eventuous/eventuous/blob/master/src/Eventuous.EventStoreDB.Subscriptions/StreamSubscriptionService.cs#L39