Unable to connect to topic via kafka interface from KafkaJS client

[gdaemon]

I've tried to consume messages from YDB topic via Kafka proxy, but got following error:

Crash: KafkaJSProtocolError: The group member's supported protocols are incompatible with those of existing members"

And in YDB there was this error message:

2025-04-03T05:22:12.409137Z :KAFKA_PROXY CRIT: TKafkaReadSessionActor consumer1_50001_0_8332942598688203394_kafka: JOIN_GROUP failed. reason# unsupported assign protocol. Must be roundrobin

After some Googling, I've found out that different languages send different strings specifying their assigner protocol, so Java, and may be others send 'roundrobin' while KafkaJS sends 'RoundRobinAssigner', which causes this issue problems.

More details regarding this issue in KafkaJS here: tulios/kafkajs#463

So there's two ways of resolving this issue:

1. Allow to use 'RoundRobinAssigner' in Kafka YDB proxy
2. Document and make examples how to create custom Assigner in KafkaJS to work with YDB in documentation site

[a-serebryanskiy]

HI! I've created a ticket to enable kafka consumer balancing.
#16736
When it will be resolved this issue should be resolved too.