[helm] Create Kubernetes Service for Agent Presets

[pkoutsovasilis]

Describe the enhancement:
Enhance the Helm chart to automatically create Kubernetes services tied to specific agent presets. These services will serve as dedicated entry points for integrations that operate in a push-based manner. This change will provide a structured and scalable way to manage and expose agent instances within the cluster.

Describe a specific use case for the enhancement or feature:
One primary use case is for push-type integrations, namely netflow, that can utilise a single Kubernetes service as a unified access point. By supporting creating such a service linked to an agent preset, users can easily scale these agents, simplifying both deployment and operational management.

What is the definition of done?

• The Helm chart can generate a Kubernetes service for agent presets.
• Examples are updated to explain how to to configure such scenario.

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[pkoutsovasilis]

@cmacknz @ycombinator @swiatekm any thoughts on this enhancement? 🙂

[swiatekm]

As a rule, should these Services default to Node-local routing by enabling the internal traffic policy? If agent is running as a DaemonSet, that would ensure behavior consistent with other Node-scoped integrations.

[pkoutsovasilis]

My idea is to avoid defaults; instead, users should configure service creation for specific presets as needed. The type and additional fields for each service would be based on the values provided by users. For instance, in the netflow case, the integration needs to listen on a specific port for incoming data. My proposal is to create a deployment-type agent preset for netflow and supply the necessary values.yaml to generate through the Helm chart a {ClusterIP|LoadBalancer|NodePort} (ExternalName isn't that suitable in any of agent needs) service with the appropriate targetPort.