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1. The Metadata request exposes topic metadata, but it does not expose topic configs. ListConfigs will make that information available to any client of the Kafka protocol and the AdminClient will expose it to normal users.
2. AlterConfigs would make it possible to update topic configs, but also client and replication quotas via the protocol and the AdminClient.
3. One should be able to tell how a topic or broker is configured including defaults and overrides.

Public Interfaces

ACLs

A new ACL resource type `Configs` will be introduced with Describe, Alter and All operations. Initially, this resource type will work at a global level like the Cluster resource type. That is, the only valid resource name will be "kafka-cluster". This leaves the door open for evolving this to be more fine-grained in the future.

Introduce 2 new ACL operations: ReadConfigs and WriteConfigsWe will introduce 2 new ACL operations: ReadConfigs and WriteConfigs. The goal is for these operations to apply to any resource that has configs. In the initial version, they will only apply to the Cluster resource type.

Protocol APIs

Wire Format types

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