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Unable to create an ephemeral pull consumer

See original GitHub issue

Defect

I am trying to create a pull subscription with ephemeral consumer using the following code:

var cc = ConsumerConfiguration.Builder()
    .WithMaxAckPending(20)
    .WithAckWait(Duration.OfSeconds(40))
    .WithMaxDeliver(1)
    .WithReplayPolicy(ReplayPolicy.Instant)
    .WithFilterSubject("auditevents")
    .Build();
jetStreamManagementContext.AddOrUpdateConsumer("auditevents", cc);

The JetStreamManagement.AddOrUpdateConsumer always verifies if Durable name is set and it is impossible to create an ephemeral consumer using any other method from JetStreamManagement.

public ConsumerInfo AddOrUpdateConsumer(
  string streamName,
  ConsumerConfiguration config)
{
  Validator.ValidateStreamName(streamName, true);
  Validator.ValidateNotNull((object) config, nameof (config));
  Validator.ValidateNotNull(config.Durable, "Durable");
  return this.AddOrUpdateConsumerInternal(streamName, config);
}

Versions of `NATS.Client` and `nats-server`:

Client: 0.14.6 Server: 2.8.4

OS/Container environment:

MacOs Monterey

Expected result:

Possibility to create a Jetstream pull subscription with ephemeral consumer.

Actual result:

System.ArgumentNullException: Value cannot be null. (Parameter 'Durable')
   at NATS.Client.Internals.Validator.ValidateNotNull(String s, String fieldName)
   at NATS.Client.JetStream.JetStreamManagement.AddOrUpdateConsumer(String streamName, ConsumerConfiguration config)

Issue Analytics

State:
Created a year ago
Comments:6

Top GitHub Comments

1reaction

scottfcommented, May 27, 2022

@robertmircea I’m waiting for this PR to be merged (https://github.com/nats-io/nats.net/pull/605), then you will be able to create ephemeral pulls.

0reactions

scottfcommented, Jun 19, 2022

Ephemeral consumers cannot be created ahead of time using management, they can only be created during the subscribe call. Please see this example and comment out the durable: https://github.com/nats-io/nats.net/blob/master/src/Samples/JetStreamPullSubBatchSize/JetStreamPullSubBatchSize.cs

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