[FLINK-38577] Added BlueGreen active deployment ingress

[drossos]

[FLINK-38577] FlinkBlueGreenDeployment Stable Ingress

What is the purpose of the change

Adds parent-level ingress support to FlinkBlueGreenDeployment, enabling users to specify ingress configuration at the BlueGreen deployment level rather than only at the child FlinkDeployment level. The ingress automatically switches between Blue and Green deployments during transitions and can be updated independently without triggering a full blue-green transition.

Brief change log

• Added ingress field to FlinkBlueGreenDeploymentSpec API

• Modified Blue and Green deployments ingress names and routes to be preappended with Blue|Green

• Implemented reconcileBlueGreenIngress() in IngressUtils for BlueGreen-specific ingress management

• Added ingress secondary resource registration in FlinkBlueGreenDeploymentController.prepareEventSources()

• Implemented reconcileIngressForActiveDeployment() in BlueGreenDeploymentService for immediate ingress updates in ACTIVE states

• Updated ActiveStateHandler to reconcile ingress during normal reconciliation loops

• Added exception handling around ingress reconciliation during finalization

• Refactored IngressUtils.getIngress() to accept IngressSpec instead of FlinkDeploymentSpec for code reuse

• Updated CRD schema to include ingress specification

  Verifying this change

  This change added tests and can be verified as follows:

  Unit Tests:

  • verifyIngressSwitchesDuringTransition
  • verifyIngressCreatedOnlyWhenConfigured

  E2E Test:

  • test_bluegreen_ingress_rotation.sh

  Also tested on remote K8s cluster with the following scenarios:

  • FlinkBlueGreenDeployment with parent-level ingress configuration
  • Ingress updates without triggering blue-green transitions
  • Ingress removal and re-addition
  • Multiple blue-green transitions with ingress present

  Does this pull request potentially affect one of the following parts:

  • Dependencies (does it add or upgrade a dependency): no
  • The public API, i.e., is any changes to the CustomResourceDescriptors: yes - adds optional ingress field to FlinkBlueGreenDeploymentSpec
  • Core observer or reconciler logic that is regularly executed: yes - adds ingress reconciliation to ActiveStateHandler and finalizeBlueGreenDeployment

  Documentation

  • Does this pull request introduce a new feature? yes
  • If yes, how is the feature documented?
    • API reference documentation updated in docs/content/docs/custom-resource/reference.md
    • CRD schema includes full ingress specification with properties documented
    • E2E test includes comprehensive comments explaining the feature
    • Javadoc added to new methods explaining when and how they're used

[gyfora]

please rebase on the latest main, then we can merge this

[drossos]

Resolved conflicts