Package com.linkedin.venice.blobtransfer

Class MetadataBasedServerBlobFinder

java.lang.Object

com.linkedin.venice.blobtransfer.MetadataBasedServerBlobFinder

All Implemented Interfaces:

BlobFinder, AutoCloseable

public class MetadataBasedServerBlobFinder
extends Object
implements BlobFinder

Discovers the Venice servers hosting a store partition so a Stateful CDC / Da Vinci client with no peer can fall back to fetching a blob from a server. Used only on the cold-start fallback path.

metadata/<store> is served by Venice servers, not the Router, so this finder uses D2 server-routing (like Fast Client's RequestBasedMetadata): it resolves the store's server D2 service, GETs metadata/<store> on a server, and reads the partition-to-replica map from MetadataResponseRecord.getRoutingInfo(), reusing the D2 client on the ClientConfig. The response is decoded against the writer schema the server advertises (via its schema id), so a server running a newer MetadataResponseRecord schema than the client is still readable. Any failure returns an empty/error response so the caller falls back to Version Topic replay -- it never returns a wrong host.

Constructor Summary

Constructors

Constructor	Description
MetadataBasedServerBlobFinder(ClientConfig clientConfig)

Method Summary

Modifier and Type	Method	Description
void	close()	Release finder-owned resources after the blob transfer manager has stopped issuing discovery requests.
BlobPeersDiscoveryResponse	discoverBlobPeers(String storeName, int version, int partitionId)	Return the server replicas hosting partitionId for the store's current serving version.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.linkedin.venice.blobtransfer.BlobFinder

shouldPreservePeerOrder

Constructor Details

MetadataBasedServerBlobFinder

public MetadataBasedServerBlobFinder(ClientConfig clientConfig)

Method Details

discoverBlobPeers

public BlobPeersDiscoveryResponse discoverBlobPeers(String storeName,
 int version,
 int partitionId)

Return the server replicas hosting partitionId for the store's current serving version.

Specified by:

discoverBlobPeers in interface BlobFinder

close

public void close()

Release finder-owned resources after the blob transfer manager has stopped issuing discovery requests.

Specified by:

close in interface AutoCloseable