jeffkbkim commented on code in PR #13870: URL: https://github.com/apache/kafka/pull/13870#discussion_r1253948479
########## group-coordinator/src/main/java/org/apache/kafka/coordinator/group/GroupCoordinatorService.java: ########## @@ -266,9 +295,21 @@ public CompletableFuture<JoinGroupResponseData> joinGroup( return FutureUtils.failedFuture(Errors.COORDINATOR_NOT_AVAILABLE.exception()); } - return FutureUtils.failedFuture(Errors.UNSUPPORTED_VERSION.exception( - "This API is not implemented yet." - )); + CompletableFuture<JoinGroupResponseData> responseFuture = new CompletableFuture<>(); + + if (!isValidGroupId(request.groupId(), ApiKeys.forId(request.apiKey()))) { + responseFuture.complete(new JoinGroupResponseData() + .setMemberId(request.memberId()) + .setErrorCode(Errors.INVALID_GROUP_ID.code())); + + return responseFuture; + } + + runtime.scheduleWriteOperation("generic-group-join", Review Comment: yeah, i will log an error for this -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org