[konlue]

Fixes #7698.

Summary

KubernetesScaler#scaleByNum constructs a bare V1Scale and dereferences its spec with Objects.requireNonNull. A fresh V1Scale has a null spec, so every replica update throws NPE before reaching the Kubernetes API — the fixed and time-window scaling policies and the dynamic scaleByAction are all dead on arrival. The NPE also escapes the surrounding catch (ApiException).

Modifications

• Initialise the spec explicitly: scale.setSpec(new V1ScaleSpec().replicas(replicaCount)) instead of requireNonNull(scale.getSpec()).setReplicas(...). V1ScaleSpec was already imported in the file.
• Add KubernetesScalerTest, the scale module's first unit test, with a Mockito-mocked AppsV1Api:
  • testScaleByNumSetsSpecBeforeReplace captures the scale passed to replaceNamespacedDeploymentScale and asserts the spec is non-null with the requested replicas.
  • testScaleByActionReadsCurrentAndAppliesDelta mocks readNamespacedDeploymentScale (replicas=2) and asserts scaleByAction(SCALE_UP) replaces with replicas=3.

Verifying this change

• Red-green: with the original requireNonNull line restored, both new tests fail with NullPointerException at KubernetesScaler.scaleByNum (matching the stack trace in the issue); with the fix they pass (2/2).

• Targeted tests pass:

  ./mvnw -B -ntp -pl shenyu-admin test -Dtest=KubernetesScalerTest

  2/2 green.

• Checkstyle passes:

  ./mvnw -B -ntp -pl shenyu-admin checkstyle:check

  clean.

Notes

The replace call's other arguments (pretty / dryRun / fieldManager / fieldValidation) stay null, unchanged. No behaviour change beyond making the call actually reach the API server.

[Aias00]

Summary

Fixes #7698. KubernetesScaler#scaleByNum constructed a bare new V1Scale() and immediately dereferenced its spec via Objects.requireNonNull(scale.getSpec()).setReplicas(...). Because a freshly built V1Scale has a null spec, every replica update threw an NPE before the Kubernetes API call — the fixed / time-window scaling policies and the dynamic scaleByAction path were all dead on arrival. The NPE also escaped the surrounding catch (ApiException).

What the change does

• shenyu-admin/.../scale/scaler/KubernetesScaler.java:73: replaces Objects.requireNonNull(scale.getSpec()).setReplicas(replicaCount) with scale.setSpec(new V1ScaleSpec().replicas(replicaCount)), so a non-null spec carrying the requested replica count reaches replaceNamespacedDeploymentScale. V1ScaleSpec was already imported, and Objects remains used in scaleByAction.
• Adds the scale module's first unit test KubernetesScalerTest.java with a Mockito-mocked AppsV1Api: testScaleByNumSetsSpecBeforeReplace asserts the captured V1Scale passed to the replace call has a non-null spec with the requested replicas; testScaleByActionReadsCurrentAndAppliesDelta mocks readNamespacedDeploymentScale (replicas=2) and asserts scaleByAction(SCALE_UP) replaces with replicas=3.

Verification

• Master comparison: master's scaleByNum used the requireNonNull(scale.getSpec()) form (as shown in the diff); head (56c0892f97c35722e5bdc99eca64339da6fe6895) uses setSpec(new V1ScaleSpec()...). V1ScaleSpec import confirmed present in the current head file; the constructor signature KubernetesScaler(Optional<AppsV1Api>, DeploymentProperties) matches the test's new KubernetesScaler(Optional.of(appsV1Api), deploymentProperties).
• Red-green is credible from the code: new V1Scale().getSpec() is null by construction, so the old line throws before the API call; the new line is a straightforward, faithful replacement with no behavioural change beyond reaching the API server.
• CI: all relevant checks pass on this head — pr_build, Analyze (java), check-license-header, rat_check, scope, sql-matrix, registry_dependencies, all build (shenyu-integrated-test-*), agent_gateway_migrations, and the e2e aggregator. No reds to attribute.

Notes

• Non-blocking: the scale module previously had no tests; adding a Mockito-based unit test here is a welcome first step. Test class uses @MockitoSettings(strictness = Strictness.LENIENT) and isNull() matchers for the trailing pretty/dryRun/fieldManager/fieldValidation args, which are correct given they are passed as null.
• No change to the other replace-call arguments; no impact on unrelated modules.

Conclusion

APPROVE. Correct, minimal fix for a real NPE that disabled the Kubernetes scaling policy paths, backed by a targeted unit test and fully green CI.