Constant API_KEY_METADATA_FETCH 

pub const API_KEY_METADATA_FETCH: i16 = _; // 1_004i16

Observer metadata fetch.

The body carries a fetch_offset, which is a KraftLog offset, and max_bytes. The response carries committed __cluster_metadata entries encoded as Kafka record batches, plus log_start_offset, high_watermark, quorum_high_watermark, a leader_hint, the responder’s leader_epoch, and the KIP-630 snapshot_id that replaces the records when the fetch offset has been pruned away.