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- Include meta key-value tags in response ("broker.id=...", "message.max.bytes=...", ...)
- Include user-defined tags in response ("aws.zone=...", "rack=...", ..)
- Using a versionInt instead of ApiVersion's id as broker protocol version.
Use a new protocol request and response, ProtocolVersionRequest and ProtocolVersionResponse. A client may use this new API to query the broker for its supported protocol request types and versions and use the information to select a suitable set of conforming API requests and versions for further communication with the broker.
- Return array of supported versions, instead of min and max of supported versions, in MetadataResponse.Return API versions in a new version of the MetadataRequest/Response
Other options that were widely discussed.
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