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Tom Bentley commented on KAFKA-13146: ------------------------------------- {quote}We have also considered whether the internal __cluster_metadata topic should be readable through the controller endpoints by consumers.{quote} That's what I had expected when originally reading the various KIPs, but exposing the metadata log comes with some downsides. Would consumers be able to do {{read_committed}} reads? > Consider client use cases for accessing controller endpoints > ------------------------------------------------------------ > > Key: KAFKA-13146 > URL: https://issues.apache.org/jira/browse/KAFKA-13146 > Project: Kafka > Issue Type: Improvement > Reporter: Jason Gustafson > Priority: Major > Labels: kip-500 > > In KAFKA-13143, we dropped the Metadata from the controller APIs. We did this > for two reasons. First, the implementation did not return any topic metadata. > This was confusing for users who mistakenly tried to use the controller > endpoint in order to describe or list topics since it would appear that no > topics existed in the cluster. The second reason is that the implementation > returned the controller endpoints. So even if we returned the topic metadata, > clients would be unable to access the topics for reading or writing through > the controller endpoint. > So for 3.0, we are effectively saying that clients should only access the > broker endpoints. Long term, is that what we want? When running the > controllers as separate nodes, it may be useful to initialize the controllers > and cluster metadata before starting any of the brokers, for example. For > this to work, we need to put some thought into how the Metadata API should > work with controllers. For example, we can return a flag or some kind of > error code in the response to indicate that topic metadata is not available. > We have also considered whether the internal __cluster_metadata topic should > be readable through the controller endpoints by consumers. -- This message was sent by Atlassian Jira (v8.3.4#803005)