✨feat(awsmachinepool): custom lifecyclehooks for machinepools

[sebltm]

What type of PR is this?
/kind feature

What this PR does / why we need it:

This PR adds to the v1beta2 definition for the AWSMachinePool and AWSManagedMachinePool with a new field lifecycleHooks which is a list of:

name: <the name of the lifecycle hook>
notificationTargetARN: <ARN of resource where to send the lifecycle event; optional>
roleARN: <ARN of role to be used when sending notifications; optional>
lifecycleTransition: <autoscaling:EC2_INSTANCE_LAUNCHING/EC2_INSTANCE_TERMINATING>
heartbeatTimeout: <duration of the heartbeat timeout; optional>
defaultResult: <CONTINUE/ABANDON; optional>
notificationMetadata: <some metadata to add to the notification; optional>

The matching webhooks are updated to validate the lifecycle hooks as they are added to the Custom Resource.
The matching reconcilers are updated to enable reconciling those lifecycle hooks: if the lifecycle hook is present in the Custom Resource but not in the cloud, it is created. And if there is a lifecycle hook present in the cloud but not declared in the Custom Resource then it is removed.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #4020

AWS supports Lifecycle Hooks before/after performing certain actions on an ASG. For example, before scaling in (removing) a node, the ASG can publish an event in an SQS queue which can them be consumed by the node-termination-handler to ensure its proper removal from Kubernetes (it will cordon, drain the node and wait for a period of time for applications to be removed before allowing the Autoscaling Group to terminate the instance).

This allows Kubernetes or other components to be aware of the node's lifecycle and take appropriate actions

Special notes for your reviewer:

Checklist:

• squashed commits
• includes documentation
• includes emojis
• adds unit tests
• adds or updates e2e tests

Release note:

Adding support for custom Lifecycle Hooks in AWSMachinePools for external hooks (e.g support for the aws-node-termination-handler with SQS)

[k8s-ci-robot]

Welcome @sebltm!

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[k8s-ci-robot]

Hi @sebltm. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[AndiDog]

I have two requests before getting to the review:

• Neither title nor PR description describe the change. Lifecycle hooks and reacting to node shutdown is great – but what is this PR doing and achieving? Also, the release note entry in the PR template must be filled.
• You're moving lots of code. Please revert those changes as much as possible so the PR becomes reviewable. Refactoring and file renames can be done separately.

[AndiDog]

/assign

[sebltm]

@AndiDog sorry I hadn't cleaned up the PR, I didn't know if it would get some traction :)
I've updated the PR, updated the description. Let me know if it looks good, I'll write some docs and add release notes

[sebltm]

@AndiDog let me know if this looks good or if there's anything else I should take a look at :)

[AndiDog]

The PR is definitely reviewable now. I'm not much experienced with lifecycle hooks and aws-node-termination-handler (is that your actual use case?). Maybe MachinePool machines (#4527) give us a good way to detect node shutdown and have CAPI/CAPA take care of it? Or in other words: I'm not fully confident reviewing here with my knowledge, but maybe others have a better clue – please feel free to ping or discuss in Slack (#cluster-api-aws) so we can find someone to check this feature request.

[AndiDog]

/ok-to-test

[AndiDog]

I noticed that CreateASG didn't handle the hooks. Likely, it's best if both are created atomically, so I added this as another commit.

[AndiDog]

@sebltm I'll try to continue here to bring it through review

[AndiDog]

/test pull-cluster-api-provider-aws-e2e

Giving it a try, but E2E might be problematic right now.

[fiunchinho]

/lgtm

[k8s-ci-robot]

New changes are detected. LGTM label has been removed.

[k8s-ci-robot]

@sebltm: 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-cluster-api-provider-aws-build-docker-release-2-6	2421ec3	link	true	/test pull-cluster-api-provider-aws-build-docker-release-2-6
pull-cluster-api-provider-aws-build-release-2-6	2421ec3	link	true	/test pull-cluster-api-provider-aws-build-release-2-6
pull-cluster-api-provider-aws-e2e	c35bbc3	link	false	/test pull-cluster-api-provider-aws-e2e

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.

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