feat(autoscaling): add support for AutoScalingInstanceRefresh UpdatePolicy#38277
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ethanshen18 wants to merge 5 commits into
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feat(autoscaling): add support for AutoScalingInstanceRefresh UpdatePolicy#38277ethanshen18 wants to merge 5 commits into
ethanshen18 wants to merge 5 commits into
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…olicy Add UpdatePolicy.instanceRefresh() so CDK users can configure the AutoScalingInstanceRefresh update policy on an Auto Scaling group. Previously CDK had no support for this policy. Includes the L1 CfnUpdatePolicy field plus cfn-include parsing, the L2 UpdatePolicy.instanceRefresh() factory with strongly-typed enums and options, README documentation, unit tests, and an integration test.
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mrmikeface
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Looks good Ethan! Where do the docs get created? I think we should consider how to make those approachable
Co-authored-by: caojason-stripe <caojason@stripe.com>
Address review feedback: rewrite the UpdatePolicy.instanceRefresh bullet to match the style of the sibling rollingUpdate/replacingUpdate bullets, and remove the now-unused instance-refresh link reference.
…pdate policy Instance refresh does not support the cfn-signal helper script, so `signals` configured on the AutoScalingGroup only gate the initial creation and are not honored during an instance refresh. Emit a synth-time warning when both are configured, and document the caveat on `UpdatePolicy.instanceRefresh()`.
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Looks great! Thanks for the linter
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Issue # (if applicable)
Closes #38276
Reason for this change
Support the newly released
AutoScalingInstanceRefreshupdate policy. This new update policy was released on 2026-07-09: https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/aws-attribute-updatepolicy.html#cfn-attributes-updatepolicy-instancerefreshDescription of changes
UpdatePolicy.instanceRefresh(options?)toaws-autoscaling, mirroring the existingrollingUpdate()/replacingUpdate()static factories. The newInstanceRefreshOptionsinterface coversstrategy,minHealthyPercentage,maxHealthyPercentage,instanceWarmup,skipMatching,checkpointPercentages,checkpointDelay,bakeTime,alarmNames,scaleInProtectedInstances, andstandbyInstances.InstanceRefreshStrategy,ScaleInProtectedInstances, andStandbyInstances— per the design guidelines.CfnUpdatePolicy.autoScalingInstanceRefreshfield and the matchingcfn-parselogic so existing templates containing this policy round-trip throughcloudformation-include.Describe any new or updated permissions being added
None. This change only configures an existing CloudFormation update policy on the
AWS::AutoScaling::AutoScalingGroupresource; it does not add or modify any IAM permissions.Description of how you validated changes
instanceRefresh()synthesis with defaults, with all options, and with strategy only; plus acfn-includeparse round-trip test for the new policy.integ.asg-instance-refresh-update-policydeployed successfully against a real AWS account; snapshot committed.UpdatePolicy.instanceRefresh(), changed the AMI to trigger the policy, and confirmed viadescribe-instance-refreshesthat the instance refresh ran toSuccessfuland honored the configured preferences (e.g.MinHealthyPercentage,InstanceWarmup), replacing all instances.Checklist
By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license