Migrate NodeHealthAPI: flip delegation so V2 owns logic, V1 bridges to it

[Copilot]

HealthCheckHandler previously owned all health-check logic and NodeHealthAPI was a thin JAX-RS wrapper that delegated back to it. This inverts that relationship: the V2 NodeHealthAPI now owns the logic and HealthCheckHandler is the thin bridge.

Key changes

NodeHealthAPI — now owns all business logic

• healthCheckCloudMode(), healthCheckLegacyMode(), isWithinGenerationLag(), findUnhealthyCores() moved here
• Uses instantiateJerseyResponse(NodeHealthResponse.class) for proper Jersey context registration
• Exposes checkNodeHealth(Boolean requireHealthyCores, Integer maxGenerationLag) for the V1 path to call
• Strongly typed throughout (NodeStatus enum, no NamedList in business logic)

HealthCheckHandler — thin V1 bridge (~10 lines of logic)

V2ApiUtils.squashIntoSolrResponseWithoutHeader(
    rsp,
    new NodeHealthAPI(coreContainer).checkNodeHealth(requireHealthyCores, maxGenerationLag));

• findUnhealthyCores() kept as a @Deprecated delegation shim pointing to NodeHealthAPI

Utils.getReflectWriter() — enum serialization fix

Enum values in a NamedList (e.g. NodeStatus.OK) previously fell through to ClassName:NAME serialization since enums have no @JsonProperty fields. Added an early-exit that returns ((Enum<?>) o).name() so they round-trip as plain strings through javabin.

Bug fixes in isWithinGenerationLag

The original condition generationDiff < maxGenerationLag was inverted — it treated healthy cores as lagging and vice versa. Corrected to > maxGenerationLag with return semantics true = within acceptable lag (healthy), false = lagging too far. Also fixed missing slf4j format arguments in the negative-diff warn call.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• develocity.apache.org
  • Triggering command: /usr/lib/jvm/temurin-21-jdk-amd64/bin/java /usr/lib/jvm/temurin-21-jdk-amd64/bin/java -XX:ReservedCodeCacheSize=256m -XX:TieredStopAtLevel=1 -XX:+UseParallelGC -XX:ActiveProcessorCount=1 --add-exports jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED --add-exports jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED --add-exports jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED --add-exports jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED --add-exports jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED --add-opens=java.base/java.util=ALL-UNNAMED --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.lang.invoke=ALL-UNNAMED --add-opens=java.prefs/java.util.prefs=ALL-UNNAMED --add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED (dns block)
• metadata.google.internal
  • Triggering command: /usr/lib/jvm/temurin-21-jdk-amd64/bin/java /usr/lib/jvm/temurin-21-jdk-amd64/bin/java -Dcommon-solr.dir=/home/REDACTED/work/solr/solr/solr -Dgradle.lib.dir=/home/REDACTED/.gradle/wrapper/dists/gradle-8.10-bin/deqhafrv1ntovfmgh0nh3npr9/gradle-8.10/lib -Dgradle.user.home=/home/REDACTED/.gradle -Dgradle.worker.jar=/home/REDACTED/.gradle/caches/8.10/workerMain/gradle-worker.jar -Djava.awt.headless=true -Djava.security.egd=file:/dev/./urandom -Djava.security.manager=default -Djava.security.policy=/home/REDACTED/work/solr/solr/gradle/testing/randomization/policies/solr-tests.policy -Djava.util.logging.config.file=/home/REDACTED/work/solr/solr/gradle/testing/defaults-tests/logging.properties -Djdk.map.althashing.threshold=0 -Djetty.insecurerandom=1 -Djetty.testMode=1 -Djunit4.childvm.count=1 -Djunit4.childvm.id=0 -Dorg.gradle.internal.worker.tmpdir=/home/REDACTED/work/solr/solr/solr/core/build/tmp/test/work -DtempDir=/home/REDACTED/work/solr/solr/build/tmp/tests-tmp -Dtests.LUCENE_VERSION=10.3.2 -Dtests.asserts=true -Dtests.codec=random (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

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[epugh]

Superseded by apache#4171 — retargeted to the upstream repo.