Implementation:Datahub project Datahub DataHubClientConfigV2

Knowledge Sources	Datahub_project_Datahub
Domains	Java_SDK, Metadata_Emission, Client_Configuration
Last Updated	2026-02-10 00:00 GMT

Overview

The top-level immutable configuration class for the DataHub Java SDK V2, wrapping server connection settings, operation mode, emit mode, cache TTLs, and providing conversion to the underlying RestEmitterConfig.

Description

DataHubClientConfigV2 is a Lombok @Value/@Builder class that serves as the primary entry point for configuring a V2 DataHub client. It introduces V2-specific concepts on top of the base REST emitter configuration:

Operation Mode (OperationMode enum):

• SDK (default) -- User-initiated edits that write to editable aspects (e.g., editableDatasetProperties). Communicated to the server via the X-DataHub-Client-Mode header.
• INGESTION -- System/pipeline writes that write to system aspects (e.g., datasetProperties).

Key fields:

• server -- DataHub GMS server URL (required).
• token -- Authentication token (optional).
• timeoutMs -- Request timeout in milliseconds (default: 10000).
• disableSslVerification -- SSL bypass for testing (default: false).
• maxRetries -- Retry count (default: 3).
• emitMode -- Controls persistence consistency tradeoff (default: SYNC_PRIMARY).
• configRefreshIntervalMs -- Server config cache TTL (default: 60000ms; 0 disables, -1 caches forever).
• aspectCacheTtlMs -- Aspect cache TTL (default: 60000ms).

Key methods:

• toRestEmitterConfig() -- Converts the V2 config to a RestEmitterConfig, mapping emit mode to async flags and headers (including X-DataHub-Client-Mode and X-DataHub-Sync-Index-Update for SYNC_WAIT mode).
• fromEnv() -- Static factory that reads DATAHUB_SERVER (or DATAHUB_GMS_URL) and DATAHUB_TOKEN (or DATAHUB_GMS_TOKEN) environment variables. Throws IllegalArgumentException if no server URL is found.

Usage

Use this class as the primary configuration for all V2 DataHub Java SDK clients. It abstracts away the details of REST emitter configuration and provides a clean, V2-specific API.

Code Reference

Source Location

metadata-integration/java/datahub-client/src/main/java/datahub/client/v2/config/DataHubClientConfigV2.java

Signature

@Value
@Builder
public class DataHubClientConfigV2 {

    public enum OperationMode { SDK, INGESTION }

    @Builder.Default @Nonnull OperationMode mode = OperationMode.SDK;
    @Nonnull String server;
    @Nullable String token;
    @Builder.Default int timeoutMs = 10000;
    @Builder.Default boolean disableSslVerification = false;
    @Builder.Default int maxRetries = 3;
    @Builder.Default @Nonnull EmitMode emitMode = EmitMode.SYNC_PRIMARY;
    @Builder.Default long configRefreshIntervalMs = 60000;
    @Builder.Default long aspectCacheTtlMs = 60000;

    @Nonnull
    public RestEmitterConfig toRestEmitterConfig()

    @Nonnull
    public static DataHubClientConfigV2 fromEnv()
}

Import

import datahub.client.v2.config.DataHubClientConfigV2;
import datahub.client.v2.config.DataHubClientConfigV2.OperationMode;

I/O Contract

Inputs

Field	Type	Default	Description
server	String (@Nonnull)	(required)	DataHub GMS server URL
token	String (@Nullable)	null	Authentication bearer token
mode	OperationMode	SDK	SDK (editable aspects) or INGESTION (system aspects)
timeoutMs	int	10000	Request timeout in milliseconds
disableSslVerification	boolean	false	Whether to skip SSL verification
maxRetries	int	3	Maximum number of retry attempts
emitMode	EmitMode	SYNC_PRIMARY	Persistence consistency mode
configRefreshIntervalMs	long	60000	Server config cache TTL (ms); 0 disables, -1 caches forever
aspectCacheTtlMs	long	60000	Aspect cache TTL (ms); 0 disables, -1 caches forever

Environment variables for fromEnv():

Variable	Fallback	Description
DATAHUB_SERVER	DATAHUB_GMS_URL	Server URL (required)
DATAHUB_TOKEN	DATAHUB_GMS_TOKEN	Authentication token (optional)

Outputs

• toRestEmitterConfig() returns a fully configured RestEmitterConfig with appropriate headers and async flags.
• fromEnv() returns a DataHubClientConfigV2 built from environment variables.

Usage Examples

// Builder-based configuration
DataHubClientConfigV2 config = DataHubClientConfigV2.builder()
    .server("http://localhost:8080")
    .token("my-token")
    .timeoutMs(30000)
    .mode(OperationMode.SDK)
    .emitMode(EmitMode.SYNC_WAIT)
    .build();

// Convert to REST emitter config
RestEmitterConfig restConfig = config.toRestEmitterConfig();

// Environment-based configuration
DataHubClientConfigV2 envConfig = DataHubClientConfigV2.fromEnv();

// Ingestion mode for pipeline writes
DataHubClientConfigV2 ingestionConfig = DataHubClientConfigV2.builder()
    .server("https://datahub.example.com")
    .mode(OperationMode.INGESTION)
    .emitMode(EmitMode.ASYNC)
    .build();

Related Pages

• Datahub_project_Datahub_RestEmitterEmitMode -- Enum controlling persistence consistency
• Datahub_project_Datahub_RestEmitterConfig -- Underlying REST config produced by toRestEmitterConfig()
• Datahub_project_Datahub_ServerConfig -- Server configuration fetched at runtime
• Datahub_project_Datahub_RequiresMutable -- Annotation for entity mutation methods