[charts/gateway] otel update, system properties expansion, ocp routes

[Gazza7205]

Description of the change

3.0.31 General Updates

• Support for Openshift Routes (disabled by default)
  • Uses passthrough termination (tls only)
    • path is ignored in this mode
  • Converts existing ingress
    • will create a route for each ingress rule
  • Management service can be routed

To enable - see ingress configuration for more details

ingress:
  enabled: true
  openshift:
    route:
      enabled: true
      wildcardPolicy: None
    # weight: 100
  ...
  rules:
  - host: dev.ca.com
    path: "/"
    service:
      port:
        name: https
  - host: dev1.ca.com
    path: "/"
    service:
      port:
        name: https
  - host: dev-pm.ca.com
    path: "/"
    backend: management
    service:
      port:
        name: management

• New way to add system properties
  • You can now use key/value pairs to extend system properties
  • No impact to existing configuration

config:
  ...
  additionalSystemProperties:
  - name: test
    value: test123

• New Deployment Configuration Options for the OTel SDK Only approach (Disabled by default)
  • Does NOT configure system or cluster-wide properties, this step is still required
  • Requires a Gateway restart when enabled
  • injects the following environment variables which are then used to set OTEL_RESOURCE_ATTRIBUTES
    • NODE_NAME ==> spec.nodeName
    • POD_NAME ==> metadata.name
    • NAMESPACE ==> metadata.namespace
    • CONTAINER_NAME ==> gateway
    • OTEL_SERVICE_NAME - <release-name>-<chart-name>
    • OTEL_RESOURCE_ATTRIBUTES ==> custom values can be set with config.otel.additionalResourceAttributes
      • defaults (if config.otel.sdkOnly.enabled is true)
        • service.name ==> OTEL_SERVICE_NAME
        • service.version ==> .Values.image.tag
        • k8s.container.name ==> gateway
        • k8s.deployment.name ==> OTEL_SERVICE_NAME
        • k8s.namespace.name ==> NAMESPACE
        • k8s.node.name ==> NODE_NAME
        • k8s.pod.name ==> POD_NAME

config:
...
  otel:
    sdkOnly:
      enabled: true
    # Used to inject additional resource attributes for tracking with the sdkOnly approach
    additionalResourceAttributes:
    - test=someEnvValue
    - test1=someEnvValue1

Benefits

• Improved support for SDK Only OTel integration
• Simpler system property configuration
• Easier to use in Openshift

Checklist

• Chart version bumped in Chart.yaml according to semver.
• Variables are documented in the README.md
• Title of the PR starts with chart name (e.g. [charts/gateway])
• If the chart contains a values-production.yaml apart from values.yaml, ensure that you implement the changes in both files

[davidchenbc]

I've looked into the otel side of the change here. Looks good.

[snagarjunas]

I have verified additionalSystemProperties. LGTM. Thanks.