feat(otel): add Karpenter metrics integration test

[vaishnavi-30-beep]

Summary

Add automated integration tests for the Karpenter metrics pipeline. Verifies that all 24 Karpenter metrics are scraped by the CloudWatch Agent and forwarded to CloudWatch with correct instrumentation scope, cluster name, namespace, and expected datapoint labels.

Changes

Test code (test/otel/integrations/karpenter/)

• setup_test.go — TestMain initialization (region, cluster, SigV4 client, QueryCache)
• metrics_test.go — 24 Karpenter metric definitions covering pods, nodes, cluster state, nodepools, cloudprovider, and disruption metrics
• karpenter_test.go — test suites:
  • MetricsExist — all metrics are queryable in CloudWatch
  • Instrumentation — scope is github.com/aws/karpenter
  • InstrumentationConsistent — no mixed sources per metric
  • ExpectedLabels — datapoint labels (resource_type, phase, method, reason) present
  • ClusterIdentity, Namespace, DeploymentName, PodName — K8s resource attributes
  • CloudProvider, CloudPlatform, CloudRegion, CloudAccountID, CloudResourceID — cloud resource attributes

Terraform (terraform/eks/daemon/otel/)

• Installs Karpenter via Helm with IAM role, Pod Identity
• Tags subnets/SGs for Karpenter discovery
• Deploys a minimal NodePool + EC2NodeClass for metric generation
• Enables otelContainerInsights.integrations.karpenter.enabled=true in the CW Agent helm values
• Adds Karpenter integration test run to the validator

Shared utility (util/otelmetrics/source_registry.go)

• Adds SourceKarpenter to the MetricSource enum

Testing

CI integration tests passing for Karpenter under eks_daemon:otel_standard_test: https://github.com/aws/amazon-cloudwatch-agent/actions/runs/28984147604/job/86009444350

Also verified locally against a live EKS cluster (karpenter-test, eu-north-1) — all tests passing.

Related

• Helm chart PR: Add Karpenter metrics integration to OTEL Container Insights aws-observability/helm-charts#325