Hi Paul. I second Ewen and I intended to give similar feedback:
1) Can we avoid a config altogether? 2) If we prefer to add a config anyways, can we use a set of allowed values instead of a boolean, even if initially these values are only two? As the discussion on Jira highlights, there is a potential for more naming conventions in the future, even if now the extra functionality doesn't seem essential. It's not optimal to have to deprecate a config instead of just extending its set of values. 3) I agree, the config name sounds too general. How about "client.ids.naming.policy" or "client.ids.naming" if you want two more options? Konstantine On Fri, Jan 4, 2019 at 7:38 AM Ewen Cheslack-Postava <e...@confluent.io> wrote: > Hi Paul, > > Thanks for the KIP. A few comments. > > To me, biggest question here is if we can fix this behavior without adding > a config. In particular, today, we don't even set the client.id for the > producer and consumer at all, right? The *only* way it is set is if you > include an override in the worker config, but in that case you need to be > explicitly opting in with a `producer.` or `consumer.` prefix, i.e. the > settings are `producer.client.id` and `consumer.client.id`. Otherwise, I > think we're getting the default behavior where we generate unique, > per-process IDs, i.e. via this logic > > https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/clients/consumer/KafkaConsumer.java#L662-L664 > > If that's the case, would it maybe be possible to compatibly change the > default to use task IDs in the client ID, but only if we don't see an > existing override from the worker config? This would only change the > behavior when someone is using the default, but since the default would > just use what is effectively a random ID that is useless for monitoring > metrics, presumably this wouldn't affect any existing users. I think that > would avoid having to introduce the config, give better out of the box > behavior, and still be a safe, compatible change to make. > > > Other than that, just two minor comments. On the config naming, not sure > about a better name, but I think the config name could be a bit clearer if > we need to have it. Maybe something including "task" like > "task.based.client.ids" or something like that (or change the type to be an > enum and make it something like task.client.ids=[default|task] and leave it > open for extension in the future if needed). > > Finally, you have this: > > *"Allow overriding client.id <http://client.id/> on a per-connector > basis"* > > > > This is a much more complex change, and would require individual > > connectors to be updated to support the change. In contrast, the proposed > > approach would immediately allow detailed consumer/producer monitoring > for > > all existing connectors. > > > > I don't think this is quite accurate. I think the reason to reject is that > for your particular requirement for metrics, it simply doesn't give enough > granularity (there's only one value per entire connector), but it doesn't > require any changes to connectors. The framework allocates all of these and > there are already framework-defined config values that all connectors share > (some for only sinks or sources), so the framework can handle all of this > without changes to connectors. Further, with connector-specific overrides, > you could get task-specific values if interpolation were supported in the > config value (as we now do with managed secrets). For example, it could > support something like client.id=connector-${taskId} and the task ID would > be substituted automatically into the string. > > I don't necessarily like that solution (seems complicated and not a great > user experience), but it could work. > > -Ewen > > > > > On Thu, Dec 20, 2018 at 5:05 PM Paul Davidson <pdavid...@salesforce.com> > wrote: > > > Hi everyone, > > > > I would like to start a discussion around the following KIP: > > * > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-411%3A+Add+option+to+make+Kafka+Connect+task+client+ID+values+unique > > < > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-411%3A+Add+option+to+make+Kafka+Connect+task+client+ID+values+unique > > >* > > > > This proposes a small change to allow Kafka Connect the option to > > auto-generate unique client IDs for each task. This enables granular > > monitoring of the producer / consumer client in each task. > > > > Feedback is appreciated, thanks in advance! > > > > Paul > > >
