[BUG] Kubernetes service uses http instead of https, causing Istio conflicts

[tombojer]

What is the bug?

The port name in the service definition is set to http even though the application listens for https. This misconfiguration may lead to issues with protocol selection in service meshes like Istio.

How can one reproduce the bug?

1. Deploy the OpenSearch Kubernetes Operator and an Opensearch cluster in an istio enabled namespace.
2. Inspect the generated service definition.
3. Observe that the port is named http, while the application actually exposes https.
4. Curl the cluster

What is the expected behavior?

The service definition should correctly reflect that the application is using https by naming the port accordingly.

What is your host/environment?

• Kubernetes Version: 1.31
• OpenSearch Kubernetes Operator Version: 2.7.0
• Cloud Provider or Platform: EKS

Do you have any screenshots?

Not applicable, but YAML snippets are provided below.

Do you have any additional context?

The current service definition incorrectly labels the port as http:

ports:
  - name: http
    port: 9200
    protocol: TCP
    targetPort: 9200

It should instead be:

ports:
  - name: https
    port: 9200
    protocol: TCP
    targetPort: 9200

Alternatively, setting the appProtocol field could also resolve the issue, as discussed in Issue #751.

For reference, the Istio documentation on protocol selection explains why proper naming is crucial for service discovery and traffic routing.