Description of the issue

To support the Explore related feature in CloudWatch, the CloudWatch Agent sends an "Entity", which includes relevant metadata to correlate metrics or logs between resources (e.g., an EKS cluster) and services (e.g., a Java application). When the CloudWatch Agent runs in a Kubernetes cluster, we need to collect the namespace, workload name, and node name to populate the "Entity".

However, we currently only get Kubernetes metadata when Application Signals is enabled. For OTLP custom metrics, if Application Signals isn't configured, then we don't have a way to fetch Kubernetes metadata. To achieve this, we must implement the Kubernetes Attributes Processor within the CloudWatch Agent.

Additionally, the process of fetching metadata with the Kubernetes Attributes Processor depends on the agent's workload type:

• Daemonset Mode:
  If the agent is running as a daemonset, we must configure a node filter. This prevents the agent from fetching metadata for pods on other nodes.

Hence, we must also implement workload type detection.

Description of changes

Revision 1

• Implements k8sattributesprocessor:
  • Add translation logic for k8sattributesprocessor to extract metadata from the application pod's IP and set node filter if the agent is a DaemonSet.
  • Add k8sattributesprocessor to otlp pipeline.
  • Update sample yaml files to include k8sattributesprocessor.
• Implement workload type detection:
  • Add getWorkloadType() in translator/util/eksdetector/eksdetector.go to query Kubernetes API with POD_NAME and K8S_NAMESPACE environmental variables and retrieve workload type from pod information.
  • Configure Workload value in IsEKSCache.
  • Reference IsEKSCache to use in DetectWorkloadType() to return workload type.
  • Add getter and setter for workload type in translator/context/context.go.
  • Set workload type in the config-translator binary.
• Add constants for DaemonSet, Deployment, and StatefulSet.
• Update and add unit tests for new functionality.

Revision 2

• Add validation for SetWorkloadType().
• Use constants for return values in getWorkloadType().
• Change "Unknown" to "" in getWorkloadType() since it serves no functional purpose.

License

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Tests

1. Created an EKS cluster and deployed the Amazon CloudWatch Observability EKS add-on.
2. Set up sample application by following https://aws-otel.github.io/docs/getting-started/adot-eks-add-on/sample-app.

• Removed resource attributes.
• Changed OTEL_EXPORTER_OTLP_ENDPOINT to http://cloudwatch-agent.amazon-cloudwatch:4317.

3. Built the agent image by running make docker-build-amd64 and changed the image in the AmazonCloudWatchAgent custom resource.

• Added debug exporter to OTLP pipeline for testing.

Kubernetes Attributes Processor

Debug Exporter Output:
K8s Metadata:

k8s.pod.name: Str(sample-app-69cdbb5f95-sqks8)
k8s.namespace.name: Str(default)
k8s.replicaset.name: Str(sample-app-69cdbb5f95)
k8s.deployment.name: Str(sample-app)
k8s.node.name: Str(ip-XXX-XX-XX-XX.us-west-2.compute.internal)

Entity Fields:

com.amazonaws.cloudwatch.entity.internal.type: Str(Service)
com.amazonaws.cloudwatch.entity.internal.service.name: Str(unknown_service:java)
com.amazonaws.cloudwatch.entity.internal.deployment.environment: Str(k8s:entity-cluster-2/default)
com.amazonaws.cloudwatch.entity.internal.platform.type: Str(K8s)
com.amazonaws.cloudwatch.entity.internal.k8s.cluster.name: Str(entity-cluster-2)
com.amazonaws.cloudwatch.entity.internal.k8s.namespace.name: Str(default)
com.amazonaws.cloudwatch.entity.internal.k8s.workload.name: Str(sample-app)
com.amazonaws.cloudwatch.entity.internal.k8s.node.name: Str(ip-XXX-XX-XX-XX.us-west-2.compute.internal)
com.amazonaws.cloudwatch.entity.internal.instance.id: Str(i-0da7f196c5fa59a25)

EMF Output:
K8s Metadata:

"k8s.deployment.name": "sample-app",
"k8s.namespace.name": "default",
"k8s.node.name": "ip-XXX-XX-XX-XX.us-west-2.compute.internal",
"k8s.pod.ip": "XXX.XX.XX.XXX",
"k8s.pod.name": "sample-app-69cdbb5f95-sqks8",
"k8s.replicaset.name": "sample-app-69cdbb5f95",

Workload Type Detection

DaemonSet:

Deployment:

Requirements

Before commit the code, please do the following steps.

1. Run make fmt and make fmt-sh
2. Run make lint