Affiliate ready state with leader election with a flag ha-enable-leader-election

[yangligt2]

Closes #1264

Summary

This PR introduces a leader election mechanism using Kubernetes Leases to allow the service to run in a high-availability (HA) mode. When enabled, only the leader instance will run the main reconciliation loop, preventing multiple replicas from acting on the same resources simultaneously.

Implementation Details

• Leverages the controller-runtime manager's built-in leader election functionality.
• A new boolean flag, --ha-enable-leader-election, is added to enable/disable this feature. It is false by default to maintain backward compatibility.
• The deployment manifest has been updated to include the necessary RBAC permissions for the service account to get, create, update, and patch leases in the coordination.k8s.io API group.

How to Test

Added 2 new test cases in test-e2e to:

1. validate that leader is with state READY 1/1
2. Delete the leader, wait for an existing pod to become the new leader, and run all existing e2e test again.

To run the test, use command E2E_LEADER_ELECTION_ENABLED=true make test-e2e

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: kfswain / name: Kellen Swain (6d01b66, 68c6ae9)
• ✅ login: yangligt2 (8e416e0, 41974d5, 67f3c0d)

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[k8s-ci-robot]

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[k8s-ci-robot]

Hi @yangligt2. Thanks for your PR.

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[kfswain]

/ok-to-test

[kfswain]

/lgtm
/approve

Comitted a small typo edit, but otherwise looks great! Thank you for this!

[kfswain]

/hold

Ahh shoot. Can we add the flag to the helm chart?

This file here:

gateway-api-inference-extension/config/charts/inferencepool/templates/epp-deployment.yaml

Line 52 in d27a716

- --lora-info-metric

[kfswain]

/lgtm
/approve

Thanks!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: kfswain, yangligt2

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[nirrozenbaum]

/hold

Ahh shoot. Can we add the flag to the helm chart?

This file here:

gateway-api-inference-extension/config/charts/inferencepool/templates/epp-deployment.yaml

Line 52 in d27a716

- --lora-info-metric

and to the chart README please.

[k8s-ci-robot]

PR needs rebase.

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[kfswain]

forgot to unhold, sorry about that!

since we need to rebase anyway, updating the readme would be great.
/unhold

[k8s-ci-robot]

@yangligt2: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-gateway-api-inference-extension-test-unit-main	6d01b66	link	unknown	/test pull-gateway-api-inference-extension-test-unit-main
pull-gateway-api-inference-extension-test-e2e-main	6d01b66	link	unknown	/test pull-gateway-api-inference-extension-test-e2e-main
pull-gateway-api-inference-extension-verify-main	6d01b66	link	unknown	/test pull-gateway-api-inference-extension-verify-main

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository. I understand the commands that are listed here.