Package com.linkedin.venice.controller

Class FabricControllerClientProvider

java.lang.Object

com.linkedin.venice.controller.FabricControllerClientProvider

All Implemented Interfaces:

Closeable, AutoCloseable

public class FabricControllerClientProvider
extends Object
implements Closeable

Owns the controller-client maps used for cross-region / cross-fabric coordination and centralizes their lazy construction and lifecycle. A single instance is created by VeniceHelixAdmin (child) and shared with VeniceParentHelixAdmin (parent), which previously each maintained their own copy of this plumbing. Two maps are maintained:

• clusterControllerClientPerFabricMap: cluster -> fabric -> client, built from the standard child data-center allowlist (URL and D2 maps) in the cluster config.
• newFabricControllerClientMap: cluster -> fabric -> client, built on demand for fabrics that are not in the standard allowlist (e.g. build-out / data-recovery destinations).

Both maps are VeniceConcurrentHashMaps populated via computeIfAbsent; no external locking is needed.

Constructor Summary

Constructors

Constructor	Description
FabricControllerClientProvider(VeniceControllerMultiClusterConfig multiClusterConfigs, Optional<SSLFactory> sslFactory, Map<String,com.linkedin.d2.balancer.D2Client> d2Clients)

Method Summary

Modifier and Type	Method	Description
void	close()
Map<String,ControllerClient>	getControllerClientMap(String clusterName)	Returns the lazily-constructed map of controller clients (fabric -> client) for the standard child data-center allowlist of the given cluster.
ControllerClient	getFabricBuildoutControllerClient(String clusterName, String fabric)	Returns a controller client for a specific fabric of the given cluster.
<R extends ControllerResponse, V> Map<String,V>	queryAllRegions(Map<String,ControllerClient> controllerClients, String clusterName, int maxAttempts, Function<ControllerClient,R> request, Function<R,V> onSuccess, V errorSentinel)	Issues the same query to every region's controller client and collects a per-region result.

Methods inherited from class java.lang.Object

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

Constructor Details

FabricControllerClientProvider

public FabricControllerClientProvider(VeniceControllerMultiClusterConfig multiClusterConfigs,
 Optional<SSLFactory> sslFactory,
 Map<String,com.linkedin.d2.balancer.D2Client> d2Clients)

Method Details

getControllerClientMap

public Map<String,ControllerClient> getControllerClientMap(String clusterName)

Returns the lazily-constructed map of controller clients (fabric -> client) for the standard child data-center allowlist of the given cluster.

getFabricBuildoutControllerClient

public ControllerClient getFabricBuildoutControllerClient(String clusterName,
 String fabric)

Returns a controller client for a specific fabric of the given cluster. Fabrics in the standard allowlist are served from getControllerClientMap(String); fabrics outside the allowlist (e.g. build-out / data-recovery destinations) are built on demand from child cluster configs and cached in newFabricControllerClientMap.

queryAllRegions

public <R extends ControllerResponse,
V>
Map<String,V> queryAllRegions(Map<String,ControllerClient> controllerClients,
 String clusterName,
 int maxAttempts,
 Function<ControllerClient,R> request,
 Function<R,V> onSuccess,
 V errorSentinel)

Issues the same query to every region's controller client and collects a per-region result. This captures the best-effort multi-fabric fan-out shape used by the parent controller's version queries: on a per-region error the failure is logged and errorSentinel is stored for that region (the query is not aborted), while a successful response is mapped to a value via onSuccess. When maxAttempts > 1 the request is retried via ControllerClient.retryableRequest(ControllerClient, int, Function).

Parameters:

controllerClients - region -> controller client (typically getControllerClientMap(String))

clusterName - the cluster being queried; used only for log context

maxAttempts - total attempts per region (1 means no retry)

request - the controller RPC to issue against each region's client

onSuccess - maps a successful response to the per-region result value

errorSentinel - the value stored for a region whose query returned an error

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable