Metrics - 01 foundation

[jitendradhawan]

Summary

Adds shared metrics infrastructure and propagates upstream identity through Ranger's common APIs.

Target branch: 2.x

Changes

• Adds MetricRecorder backed by Dropwizard MetricRegistry.
• Adds DataStoreType (ZK, HTTP, DROVE).
• Adds getUpstreamId() and getDataStoreType() metadata to NodeDataSource and NodeDataSink.
• Propagates upstreamId through finder/provider builders, hub clients, backend connectors, and factories.
• Adds Dropwizard Metrics and validation dependencies required by the new contracts.
• Keeps all metric recording calls and bundle initialization out of this change; those are covered by subsequent stacked MRs.

Compatibility / Migration

This is a source-compatible change only for callers that update their implementations and builders:

• Custom sources and sinks must implement getUpstreamId() and getDataStoreType().
• Custom builder overrides must accept upstreamId in source/sink factory methods.
• Direct client, builder, connector, and factory callers must propagate a non-null upstream ID.

Testing

• Full reactor compilation passes with mvn -DskipTests compile.
• Focused behavior tests are added in later backend/core MRs.

Reviewer Guide

• Verify upstream ID propagation does not alter discovery behavior.
• Check that public/protected extension points are consistently updated.
• Confirm MetricRecorder is a no-op before registry initialization.
• Confirm this MR contains no backend-specific metric side effects.

[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.8% Duplication on New Code

See analysis details on SonarQube Cloud