aws-cdk-lib
Version:
Version 2 of the AWS Cloud Development Kit library
860 lines (593 loc) • 86 kB
Markdown
# CDK Feature Flags
[CDK Feature Flags](https://docs.aws.amazon.com/cdk/v2/guide/featureflags.html) are a mechanism that allows the CDK to evolve and change the behavior of certain classes and methods, without causing disruption to existing deployed infrastructure.
Feature flags are [context values](https://docs.aws.amazon.com/cdk/v2/guide/context.html) and can be configured using any of the context management methods, at any level of the construct tree. Commonly, they are specified in the `cdk.json` file.
`cdk init` will create new CDK projects with a `cdk.json` file containing all recommended feature flags enabled.
## Current list of feature flags
Flags come in three types:
- **Default change**: The default behavior of an API has been changed in order to improve its ergonomics. The old behavior can still be achieved, but requires source changes.
- **Fix/deprecation**: The old behavior was incorrect or not recommended for new users. The only way to keep it is to not set this flag.
- **Config**: Configurable behavior that we recommend you turn on.
<!-- BEGIN table -->
| Flag | Summary | Since | Type |
| ----- | ----- | ----- | ----- |
| [@aws-cdk/core:newStyleStackSynthesis](#aws-cdkcorenewstylestacksynthesis) | Switch to new stack synthesis method which enables CI/CD | 2.0.0 | (fix) |
| [@aws-cdk/core:stackRelativeExports](#aws-cdkcorestackrelativeexports) | Name exports based on the construct paths relative to the stack, rather than the global construct path | 2.0.0 | (fix) |
| [@aws-cdk/aws-rds:lowercaseDbIdentifier](#aws-cdkaws-rdslowercasedbidentifier) | Force lowercasing of RDS Cluster names in CDK | 2.0.0 | (fix) |
| [@aws-cdk/aws-apigateway:usagePlanKeyOrderInsensitiveId](#aws-cdkaws-apigatewayusageplankeyorderinsensitiveid) | Allow adding/removing multiple UsagePlanKeys independently | 2.0.0 | (fix) |
| [@aws-cdk/aws-lambda:recognizeVersionProps](#aws-cdkaws-lambdarecognizeversionprops) | Enable this feature flag to opt in to the updated logical id calculation for Lambda Version created using the `fn.currentVersion`. | 2.0.0 | (fix) |
| [@aws-cdk/aws-cloudfront:defaultSecurityPolicyTLSv1.2\_2021](#aws-cdkaws-cloudfrontdefaultsecuritypolicytlsv12_2021) | Enable this feature flag to have cloudfront distributions use the security policy TLSv1.2_2021 by default. | 2.0.0 | (fix) |
| [@aws-cdk/core:target-partitions](#aws-cdkcoretarget-partitions) | What regions to include in lookup tables of environment agnostic stacks | 2.4.0 | (config) |
| [@aws-cdk-containers/ecs-service-extensions:enableDefaultLogDriver](#aws-cdk-containersecs-service-extensionsenabledefaultlogdriver) | ECS extensions will automatically add an `awslogs` driver if no logging is specified | 2.8.0 | (default) |
| [@aws-cdk/aws-ec2:uniqueImdsv2TemplateName](#aws-cdkaws-ec2uniqueimdsv2templatename) | Enable this feature flag to have Launch Templates generated by the `InstanceRequireImdsv2Aspect` use unique names. | 2.8.0 | (fix) |
| [@aws-cdk/aws-iam:minimizePolicies](#aws-cdkaws-iamminimizepolicies) | Minimize IAM policies by combining Statements | 2.18.0 | (config) |
| [@aws-cdk/core:checkSecretUsage](#aws-cdkcorechecksecretusage) | Enable this flag to make it impossible to accidentally use SecretValues in unsafe locations | 2.21.0 | (config) |
| [@aws-cdk/aws-lambda:recognizeLayerVersion](#aws-cdkaws-lambdarecognizelayerversion) | Enable this feature flag to opt in to the updated logical id calculation for Lambda Version created using the `fn.currentVersion`. | 2.27.0 | (fix) |
| [@aws-cdk/core:validateSnapshotRemovalPolicy](#aws-cdkcorevalidatesnapshotremovalpolicy) | Error on snapshot removal policies on resources that do not support it. | 2.28.0 | (default) |
| [@aws-cdk/aws-codepipeline:crossAccountKeyAliasStackSafeResourceName](#aws-cdkaws-codepipelinecrossaccountkeyaliasstacksaferesourcename) | Generate key aliases that include the stack name | 2.29.0 | (fix) |
| [@aws-cdk/aws-s3:createDefaultLoggingPolicy](#aws-cdkaws-s3createdefaultloggingpolicy) | Enable this feature flag to create an S3 bucket policy by default in cases where an AWS service would automatically create the Policy if one does not exist. | 2.31.0 | (fix) |
| [@aws-cdk/aws-sns-subscriptions:restrictSqsDescryption](#aws-cdkaws-sns-subscriptionsrestrictsqsdescryption) | Restrict KMS key policy for encrypted Queues a bit more | 2.32.0 | (fix) |
| [@aws-cdk/aws-ecs:arnFormatIncludesClusterName](#aws-cdkaws-ecsarnformatincludesclustername) | ARN format used by ECS. In the new ARN format, the cluster name is part of the resource ID. | 2.35.0 | (fix) |
| [@aws-cdk/aws-apigateway:disableCloudWatchRole](#aws-cdkaws-apigatewaydisablecloudwatchrole) | Make default CloudWatch Role behavior safe for multiple API Gateways in one environment | 2.38.0 | (fix) |
| [@aws-cdk/core:enablePartitionLiterals](#aws-cdkcoreenablepartitionliterals) | Make ARNs concrete if AWS partition is known | 2.38.0 | (fix) |
| [@aws-cdk/aws-ecs:disableExplicitDeploymentControllerForCircuitBreaker](#aws-cdkaws-ecsdisableexplicitdeploymentcontrollerforcircuitbreaker) | Avoid setting the "ECS" deployment controller when adding a circuit breaker | 2.51.0 | (fix) |
| [@aws-cdk/aws-events:eventsTargetQueueSameAccount](#aws-cdkaws-eventseventstargetqueuesameaccount) | Event Rules may only push to encrypted SQS queues in the same account | 2.51.0 | (fix) |
| [@aws-cdk/aws-iam:importedRoleStackSafeDefaultPolicyName](#aws-cdkaws-iamimportedrolestacksafedefaultpolicyname) | Enable this feature to by default create default policy names for imported roles that depend on the stack the role is in. | 2.60.0 | (fix) |
| [@aws-cdk/aws-s3:serverAccessLogsUseBucketPolicy](#aws-cdkaws-s3serveraccesslogsusebucketpolicy) | Use S3 Bucket Policy instead of ACLs for Server Access Logging | 2.60.0 | (fix) |
| [@aws-cdk/customresources:installLatestAwsSdkDefault](#aws-cdkcustomresourcesinstalllatestawssdkdefault) | Whether to install the latest SDK by default in AwsCustomResource | 2.60.0 | (default) |
| [@aws-cdk/aws-route53-patters:useCertificate](#aws-cdkaws-route53-pattersusecertificate) | Use the official `Certificate` resource instead of `DnsValidatedCertificate` | 2.61.0 | (default) |
| [@aws-cdk/aws-codedeploy:removeAlarmsFromDeploymentGroup](#aws-cdkaws-codedeployremovealarmsfromdeploymentgroup) | Remove CloudWatch alarms from deployment group | 2.65.0 | (fix) |
| [@aws-cdk/aws-rds:databaseProxyUniqueResourceName](#aws-cdkaws-rdsdatabaseproxyuniqueresourcename) | Use unique resource name for Database Proxy | 2.65.0 | (fix) |
| [@aws-cdk/aws-apigateway:authorizerChangeDeploymentLogicalId](#aws-cdkaws-apigatewayauthorizerchangedeploymentlogicalid) | Include authorizer configuration in the calculation of the API deployment logical ID. | 2.66.0 | (fix) |
| [@aws-cdk/aws-ec2:launchTemplateDefaultUserData](#aws-cdkaws-ec2launchtemplatedefaultuserdata) | Define user data for a launch template by default when a machine image is provided. | 2.67.0 | (fix) |
| [@aws-cdk/aws-secretsmanager:useAttachedSecretResourcePolicyForSecretTargetAttachments](#aws-cdkaws-secretsmanageruseattachedsecretresourcepolicyforsecrettargetattachments) | SecretTargetAttachments uses the ResourcePolicy of the attached Secret. | 2.67.0 | (fix) |
| [@aws-cdk/aws-redshift:columnId](#aws-cdkaws-redshiftcolumnid) | Whether to use an ID to track Redshift column changes | 2.68.0 | (fix) |
| [@aws-cdk/aws-stepfunctions-tasks:enableEmrServicePolicyV2](#aws-cdkaws-stepfunctions-tasksenableemrservicepolicyv2) | Enable AmazonEMRServicePolicy_v2 managed policies | 2.72.0 | (fix) |
| [@aws-cdk/aws-apigateway:requestValidatorUniqueId](#aws-cdkaws-apigatewayrequestvalidatoruniqueid) | Generate a unique id for each RequestValidator added to a method | 2.78.0 | (fix) |
| [@aws-cdk/aws-ec2:restrictDefaultSecurityGroup](#aws-cdkaws-ec2restrictdefaultsecuritygroup) | Restrict access to the VPC default security group | 2.78.0 | (default) |
| [@aws-cdk/aws-kms:aliasNameRef](#aws-cdkaws-kmsaliasnameref) | KMS Alias name and keyArn will have implicit reference to KMS Key | 2.83.0 | (fix) |
| [@aws-cdk/core:includePrefixInUniqueNameGeneration](#aws-cdkcoreincludeprefixinuniquenamegeneration) | Include the stack prefix in the stack name generation process | 2.84.0 | (fix) |
| [@aws-cdk/aws-autoscaling:generateLaunchTemplateInsteadOfLaunchConfig](#aws-cdkaws-autoscalinggeneratelaunchtemplateinsteadoflaunchconfig) | Generate a launch template when creating an AutoScalingGroup | 2.88.0 | (fix) |
| [@aws-cdk/aws-opensearchservice:enableOpensearchMultiAzWithStandby](#aws-cdkaws-opensearchserviceenableopensearchmultiazwithstandby) | Enables support for Multi-AZ with Standby deployment for opensearch domains | 2.88.0 | (default) |
| [@aws-cdk/aws-efs:denyAnonymousAccess](#aws-cdkaws-efsdenyanonymousaccess) | EFS denies anonymous clients accesses | 2.93.0 | (default) |
| [@aws-cdk/aws-efs:mountTargetOrderInsensitiveLogicalId](#aws-cdkaws-efsmounttargetorderinsensitivelogicalid) | When enabled, mount targets will have a stable logicalId that is linked to the associated subnet. | 2.93.0 | (fix) |
| [@aws-cdk/aws-lambda-nodejs:useLatestRuntimeVersion](#aws-cdkaws-lambda-nodejsuselatestruntimeversion) | Enables aws-lambda-nodejs.Function to use the latest available NodeJs runtime as the default | 2.93.0 | (default) |
| [@aws-cdk/aws-appsync:useArnForSourceApiAssociationIdentifier](#aws-cdkaws-appsyncusearnforsourceapiassociationidentifier) | When enabled, will always use the arn for identifiers for CfnSourceApiAssociation in the GraphqlApi construct rather than id. | 2.97.0 | (fix) |
| [@aws-cdk/aws-rds:auroraClusterChangeScopeOfInstanceParameterGroupWithEachParameters](#aws-cdkaws-rdsauroraclusterchangescopeofinstanceparametergroupwitheachparameters) | When enabled, a scope of InstanceParameterGroup for AuroraClusterInstance with each parameters will change. | 2.97.0 | (fix) |
| [@aws-cdk/aws-rds:preventRenderingDeprecatedCredentials](#aws-cdkaws-rdspreventrenderingdeprecatedcredentials) | When enabled, creating an RDS database cluster from a snapshot will only render credentials for snapshot credentials. | 2.98.0 | (fix) |
| [@aws-cdk/aws-codepipeline-actions:useNewDefaultBranchForCodeCommitSource](#aws-cdkaws-codepipeline-actionsusenewdefaultbranchforcodecommitsource) | When enabled, the CodeCommit source action is using the default branch name 'main'. | 2.103.1 | (fix) |
| [@aws-cdk/aws-cloudwatch-actions:changeLambdaPermissionLogicalIdForLambdaAction](#aws-cdkaws-cloudwatch-actionschangelambdapermissionlogicalidforlambdaaction) | When enabled, the logical ID of a Lambda permission for a Lambda action includes an alarm ID. | 2.124.0 | (fix) |
| [@aws-cdk/aws-codepipeline:crossAccountKeysDefaultValueToFalse](#aws-cdkaws-codepipelinecrossaccountkeysdefaultvaluetofalse) | Enables Pipeline to set the default value for crossAccountKeys to false. | 2.127.0 | (default) |
| [@aws-cdk/aws-codepipeline:defaultPipelineTypeToV2](#aws-cdkaws-codepipelinedefaultpipelinetypetov2) | Enables Pipeline to set the default pipeline type to V2. | 2.133.0 | (default) |
| [@aws-cdk/aws-kms:reduceCrossAccountRegionPolicyScope](#aws-cdkaws-kmsreducecrossaccountregionpolicyscope) | When enabled, IAM Policy created from KMS key grant will reduce the resource scope to this key only. | 2.134.0 | (fix) |
| [@aws-cdk/aws-eks:nodegroupNameAttribute](#aws-cdkaws-eksnodegroupnameattribute) | When enabled, nodegroupName attribute of the provisioned EKS NodeGroup will not have the cluster name prefix. | 2.139.0 | (fix) |
| [@aws-cdk/aws-ec2:ebsDefaultGp3Volume](#aws-cdkaws-ec2ebsdefaultgp3volume) | When enabled, the default volume type of the EBS volume will be GP3 | 2.140.0 | (default) |
| [@aws-cdk/pipelines:reduceAssetRoleTrustScope](#aws-cdkpipelinesreduceassetroletrustscope) | Remove the root account principal from PipelineAssetsFileRole trust policy | 2.141.0 | (default) |
| [@aws-cdk/aws-ecs:removeDefaultDeploymentAlarm](#aws-cdkaws-ecsremovedefaultdeploymentalarm) | When enabled, remove default deployment alarm settings | 2.143.0 | (default) |
| [@aws-cdk/custom-resources:logApiResponseDataPropertyTrueDefault](#aws-cdkcustom-resourceslogapiresponsedatapropertytruedefault) | When enabled, the custom resource used for `AwsCustomResource` will configure the `logApiResponseData` property as true by default | 2.145.0 | (fix) |
| [@aws-cdk/aws-s3:keepNotificationInImportedBucket](#aws-cdkaws-s3keepnotificationinimportedbucket) | When enabled, Adding notifications to a bucket in the current stack will not remove notification from imported stack. | 2.155.0 | (fix) |
| [@aws-cdk/aws-stepfunctions-tasks:useNewS3UriParametersForBedrockInvokeModelTask](#aws-cdkaws-stepfunctions-tasksusenews3uriparametersforbedrockinvokemodeltask) | When enabled, use new props for S3 URI field in task definition of state machine for bedrock invoke model. | 2.156.0 | (fix) |
| [@aws-cdk/aws-ecs:reduceEc2FargateCloudWatchPermissions](#aws-cdkaws-ecsreduceec2fargatecloudwatchpermissions) | When enabled, we will only grant the necessary permissions when users specify cloudwatch log group through logConfiguration | 2.159.0 | (fix) |
| [@aws-cdk/aws-ec2:ec2SumTImeoutEnabled](#aws-cdkaws-ec2ec2sumtimeoutenabled) | When enabled, initOptions.timeout and resourceSignalTimeout values will be summed together. | 2.160.0 | (fix) |
| [@aws-cdk/aws-appsync:appSyncGraphQLAPIScopeLambdaPermission](#aws-cdkaws-appsyncappsyncgraphqlapiscopelambdapermission) | When enabled, a Lambda authorizer Permission created when using GraphqlApi will be properly scoped with a SourceArn. | 2.161.0 | (fix) |
| [@aws-cdk/aws-lambda-nodejs:sdkV3ExcludeSmithyPackages](#aws-cdkaws-lambda-nodejssdkv3excludesmithypackages) | When enabled, both `@aws-sdk` and `@smithy` packages will be excluded from the Lambda Node.js 18.x runtime to prevent version mismatches in bundled applications. | 2.161.0 | (fix) |
| [@aws-cdk/aws-rds:setCorrectValueForDatabaseInstanceReadReplicaInstanceResourceId](#aws-cdkaws-rdssetcorrectvaluefordatabaseinstancereadreplicainstanceresourceid) | When enabled, the value of property `instanceResourceId` in construct `DatabaseInstanceReadReplica` will be set to the correct value which is `DbiResourceId` instead of currently `DbInstanceArn` | 2.161.0 | (fix) |
| [@aws-cdk/core:cfnIncludeRejectComplexResourceUpdateCreatePolicyIntrinsics](#aws-cdkcorecfnincluderejectcomplexresourceupdatecreatepolicyintrinsics) | When enabled, CFN templates added with `cfn-include` will error if the template contains Resource Update or Create policies with CFN Intrinsics that include non-primitive values. | 2.161.0 | (fix) |
| [@aws-cdk/aws-stepfunctions-tasks:fixRunEcsTaskPolicy](#aws-cdkaws-stepfunctions-tasksfixrunecstaskpolicy) | When enabled, the resource of IAM Run Ecs policy generated by SFN EcsRunTask will reference the definition, instead of constructing ARN. | 2.163.0 | (fix) |
| [@aws-cdk/aws-dynamodb:resourcePolicyPerReplica](#aws-cdkaws-dynamodbresourcepolicyperreplica) | When enabled will allow you to specify a resource policy per replica, and not copy the source table policy to all replicas | 2.164.0 | (fix) |
| [@aws-cdk/aws-ec2:bastionHostUseAmazonLinux2023ByDefault](#aws-cdkaws-ec2bastionhostuseamazonlinux2023bydefault) | When enabled, the BastionHost construct will use the latest Amazon Linux 2023 AMI, instead of Amazon Linux 2. | 2.172.0 | (default) |
| [@aws-cdk/core:aspectStabilization](#aws-cdkcoreaspectstabilization) | When enabled, a stabilization loop will be run when invoking Aspects during synthesis. | 2.172.0 | (config) |
| [@aws-cdk/aws-route53-targets:userPoolDomainNameMethodWithoutCustomResource](#aws-cdkaws-route53-targetsuserpooldomainnamemethodwithoutcustomresource) | When enabled, use a new method for DNS Name of user pool domain target without creating a custom resource. | 2.174.0 | (fix) |
| [@aws-cdk/aws-ecs:disableEcsImdsBlocking](#aws-cdkaws-ecsdisableecsimdsblocking) | When set to true, CDK synth will throw exception if canContainersAccessInstanceRole is false. **IMPORTANT: See [details.](#aws-cdkaws-ecsdisableEcsImdsBlocking)** | 2.175.0 | (temporary) |
| [@aws-cdk/aws-ecs:enableImdsBlockingDeprecatedFeature](#aws-cdkaws-ecsenableimdsblockingdeprecatedfeature) | When set to true along with canContainersAccessInstanceRole=false in ECS cluster, new updated commands will be added to UserData to block container accessing IMDS. **Applicable to Linux only. IMPORTANT: See [details.](#aws-cdkaws-ecsenableImdsBlockingDeprecatedFeature)** | 2.175.0 | (temporary) |
| [@aws-cdk/aws-elasticloadbalancingV2:albDualstackWithoutPublicIpv4SecurityGroupRulesDefault](#aws-cdkaws-elasticloadbalancingv2albdualstackwithoutpublicipv4securitygrouprulesdefault) | When enabled, the default security group ingress rules will allow IPv6 ingress from anywhere | 2.176.0 | (fix) |
| [@aws-cdk/aws-iam:oidcRejectUnauthorizedConnections](#aws-cdkaws-iamoidcrejectunauthorizedconnections) | When enabled, the default behaviour of OIDC provider will reject unauthorized connections | 2.177.0 | (fix) |
| [@aws-cdk/core:enableAdditionalMetadataCollection](#aws-cdkcoreenableadditionalmetadatacollection) | When enabled, CDK will expand the scope of usage data collected to better inform CDK development and improve communication for security concerns and emerging issues. | 2.178.0 | (config) |
| [@aws-cdk/aws-lambda:createNewPoliciesWithAddToRolePolicy](#aws-cdkaws-lambdacreatenewpolicieswithaddtorolepolicy) | When enabled, Lambda will create new inline policies with AddToRolePolicy instead of adding to the Default Policy Statement | 2.180.0 | (fix) |
| [@aws-cdk/aws-s3:setUniqueReplicationRoleName](#aws-cdkaws-s3setuniquereplicationrolename) | When enabled, CDK will automatically generate a unique role name that is used for s3 object replication. | 2.182.0 | (fix) |
| [@aws-cdk/pipelines:reduceStageRoleTrustScope](#aws-cdkpipelinesreducestageroletrustscope) | Remove the root account principal from Stage addActions trust policy | 2.184.0 | (default) |
<!-- END table -->
## Currently recommended cdk.json
The following json shows the current recommended set of flags, as `cdk init` would generate it for new projects.
<!-- BEGIN json -->
```json
{
"context": {
"@aws-cdk/aws-lambda:recognizeLayerVersion": true,
"@aws-cdk/core:checkSecretUsage": true,
"@aws-cdk/core:target-partitions": [
"aws",
"aws-cn"
],
"@aws-cdk-containers/ecs-service-extensions:enableDefaultLogDriver": true,
"@aws-cdk/aws-ec2:uniqueImdsv2TemplateName": true,
"@aws-cdk/aws-ecs:arnFormatIncludesClusterName": true,
"@aws-cdk/aws-iam:minimizePolicies": true,
"@aws-cdk/core:validateSnapshotRemovalPolicy": true,
"@aws-cdk/aws-codepipeline:crossAccountKeyAliasStackSafeResourceName": true,
"@aws-cdk/aws-s3:createDefaultLoggingPolicy": true,
"@aws-cdk/aws-sns-subscriptions:restrictSqsDescryption": true,
"@aws-cdk/aws-apigateway:disableCloudWatchRole": true,
"@aws-cdk/core:enablePartitionLiterals": true,
"@aws-cdk/aws-events:eventsTargetQueueSameAccount": true,
"@aws-cdk/aws-ecs:disableExplicitDeploymentControllerForCircuitBreaker": true,
"@aws-cdk/aws-iam:importedRoleStackSafeDefaultPolicyName": true,
"@aws-cdk/aws-s3:serverAccessLogsUseBucketPolicy": true,
"@aws-cdk/aws-route53-patters:useCertificate": true,
"@aws-cdk/customresources:installLatestAwsSdkDefault": false,
"@aws-cdk/aws-rds:databaseProxyUniqueResourceName": true,
"@aws-cdk/aws-codedeploy:removeAlarmsFromDeploymentGroup": true,
"@aws-cdk/aws-apigateway:authorizerChangeDeploymentLogicalId": true,
"@aws-cdk/aws-ec2:launchTemplateDefaultUserData": true,
"@aws-cdk/aws-secretsmanager:useAttachedSecretResourcePolicyForSecretTargetAttachments": true,
"@aws-cdk/aws-redshift:columnId": true,
"@aws-cdk/aws-stepfunctions-tasks:enableEmrServicePolicyV2": true,
"@aws-cdk/aws-ec2:restrictDefaultSecurityGroup": true,
"@aws-cdk/aws-apigateway:requestValidatorUniqueId": true,
"@aws-cdk/aws-kms:aliasNameRef": true,
"@aws-cdk/aws-autoscaling:generateLaunchTemplateInsteadOfLaunchConfig": true,
"@aws-cdk/core:includePrefixInUniqueNameGeneration": true,
"@aws-cdk/aws-efs:denyAnonymousAccess": true,
"@aws-cdk/aws-opensearchservice:enableOpensearchMultiAzWithStandby": true,
"@aws-cdk/aws-lambda-nodejs:useLatestRuntimeVersion": true,
"@aws-cdk/aws-efs:mountTargetOrderInsensitiveLogicalId": true,
"@aws-cdk/aws-rds:auroraClusterChangeScopeOfInstanceParameterGroupWithEachParameters": true,
"@aws-cdk/aws-appsync:useArnForSourceApiAssociationIdentifier": true,
"@aws-cdk/aws-rds:preventRenderingDeprecatedCredentials": true,
"@aws-cdk/aws-codepipeline-actions:useNewDefaultBranchForCodeCommitSource": true,
"@aws-cdk/aws-cloudwatch-actions:changeLambdaPermissionLogicalIdForLambdaAction": true,
"@aws-cdk/aws-codepipeline:crossAccountKeysDefaultValueToFalse": true,
"@aws-cdk/aws-codepipeline:defaultPipelineTypeToV2": true,
"@aws-cdk/aws-kms:reduceCrossAccountRegionPolicyScope": true,
"@aws-cdk/aws-eks:nodegroupNameAttribute": true,
"@aws-cdk/aws-ec2:ebsDefaultGp3Volume": true,
"@aws-cdk/aws-ecs:removeDefaultDeploymentAlarm": true,
"@aws-cdk/custom-resources:logApiResponseDataPropertyTrueDefault": false,
"@aws-cdk/aws-s3:keepNotificationInImportedBucket": false,
"@aws-cdk/aws-ecs:enableImdsBlockingDeprecatedFeature": false,
"@aws-cdk/aws-ecs:disableEcsImdsBlocking": true,
"@aws-cdk/aws-ecs:reduceEc2FargateCloudWatchPermissions": true,
"@aws-cdk/aws-dynamodb:resourcePolicyPerReplica": true,
"@aws-cdk/aws-ec2:ec2SumTImeoutEnabled": true,
"@aws-cdk/aws-appsync:appSyncGraphQLAPIScopeLambdaPermission": true,
"@aws-cdk/aws-rds:setCorrectValueForDatabaseInstanceReadReplicaInstanceResourceId": true,
"@aws-cdk/core:cfnIncludeRejectComplexResourceUpdateCreatePolicyIntrinsics": true,
"@aws-cdk/aws-lambda-nodejs:sdkV3ExcludeSmithyPackages": true,
"@aws-cdk/aws-stepfunctions-tasks:fixRunEcsTaskPolicy": true,
"@aws-cdk/aws-ec2:bastionHostUseAmazonLinux2023ByDefault": true,
"@aws-cdk/aws-route53-targets:userPoolDomainNameMethodWithoutCustomResource": true,
"@aws-cdk/aws-elasticloadbalancingV2:albDualstackWithoutPublicIpv4SecurityGroupRulesDefault": true,
"@aws-cdk/aws-iam:oidcRejectUnauthorizedConnections": true,
"@aws-cdk/core:enableAdditionalMetadataCollection": true,
"@aws-cdk/aws-lambda:createNewPoliciesWithAddToRolePolicy": true,
"@aws-cdk/aws-s3:setUniqueReplicationRoleName": true
}
}
```
<!-- END json -->
## Flags removed in v2
These **default change** flags have been removed in v2. These used to be configurable in v1, but in v2 their
behavior has become the default. Remove these from your `cdk.json` file. If the old behavior is important
for your infrastructure, see the flag's description on how to achieve it.
<!-- BEGIN removed -->
| Flag | Summary | Type | Since |
| ----- | ----- | ----- | ----- |
| [@aws-cdk/core:enableStackNameDuplicates](#aws-cdkcoreenablestacknameduplicates) | Allow multiple stacks with the same name | (default) | 1.16.0 |
| [aws-cdk:enableDiffNoFail](#aws-cdkenablediffnofail) | Make `cdk diff` not fail when there are differences | (default) | 1.19.0 |
| [@aws-cdk/aws-ecr-assets:dockerIgnoreSupport](#aws-cdkaws-ecr-assetsdockerignoresupport) | DockerImageAsset properly supports `.dockerignore` files by default | (default) | 1.73.0 |
| [@aws-cdk/aws-secretsmanager:parseOwnedSecretName](#aws-cdkaws-secretsmanagerparseownedsecretname) | Fix the referencing of SecretsManager names from ARNs | (default) | 1.77.0 |
| [@aws-cdk/aws-kms:defaultKeyPolicies](#aws-cdkaws-kmsdefaultkeypolicies) | Tighten default KMS key policies | (default) | 1.78.0 |
| [@aws-cdk/aws-s3:grantWriteWithoutAcl](#aws-cdkaws-s3grantwritewithoutacl) | Remove `PutObjectAcl` from Bucket.grantWrite | (default) | 1.85.0 |
| [@aws-cdk/aws-ecs-patterns:removeDefaultDesiredCount](#aws-cdkaws-ecs-patternsremovedefaultdesiredcount) | Do not specify a default DesiredCount for ECS services | (default) | 1.92.0 |
| [@aws-cdk/aws-efs:defaultEncryptionAtRest](#aws-cdkaws-efsdefaultencryptionatrest) | Enable this feature flag to have elastic file systems encrypted at rest by default. | (default) | 1.98.0 |
<!-- END removed -->
## Flags with a different default in v2
These **fix/deprecation** flags are still configurable in v2, but their default has changed compared to v1. If you
are migrating a v1 CDK project to v2, explicitly set any of these flags which does not currently appear in your
`cdk.json` to `false`, to avoid unexpected infrastructure changes.
<!-- BEGIN diff -->
| Flag | Summary | Type | Since | v1 default | v2 default |
| ----- | ----- | ----- | ----- | ----- | ----- |
| [@aws-cdk/core:newStyleStackSynthesis](#aws-cdkcorenewstylestacksynthesis) | Switch to new stack synthesis method which enables CI/CD | (fix) | 1.39.0 | `false` | `true` |
| [@aws-cdk/core:stackRelativeExports](#aws-cdkcorestackrelativeexports) | Name exports based on the construct paths relative to the stack, rather than the global construct path | (fix) | 1.58.0 | `false` | `true` |
| [@aws-cdk/aws-rds:lowercaseDbIdentifier](#aws-cdkaws-rdslowercasedbidentifier) | Force lowercasing of RDS Cluster names in CDK | (fix) | 1.97.0 | `false` | `true` |
| [@aws-cdk/aws-apigateway:usagePlanKeyOrderInsensitiveId](#aws-cdkaws-apigatewayusageplankeyorderinsensitiveid) | Allow adding/removing multiple UsagePlanKeys independently | (fix) | 1.98.0 | `false` | `true` |
| [@aws-cdk/aws-lambda:recognizeVersionProps](#aws-cdkaws-lambdarecognizeversionprops) | Enable this feature flag to opt in to the updated logical id calculation for Lambda Version created using the `fn.currentVersion`. | (fix) | 1.106.0 | `false` | `true` |
| [@aws-cdk/aws-cloudfront:defaultSecurityPolicyTLSv1.2\_2021](#aws-cdkaws-cloudfrontdefaultsecuritypolicytlsv12_2021) | Enable this feature flag to have cloudfront distributions use the security policy TLSv1.2_2021 by default. | (fix) | 1.117.0 | `false` | `true` |
| [@aws-cdk/pipelines:reduceAssetRoleTrustScope](#aws-cdkpipelinesreduceassetroletrustscope) | Remove the root account principal from PipelineAssetsFileRole trust policy | (default) | | `false` | `true` |
| [@aws-cdk/aws-stepfunctions-tasks:useNewS3UriParametersForBedrockInvokeModelTask](#aws-cdkaws-stepfunctions-tasksusenews3uriparametersforbedrockinvokemodeltask) | When enabled, use new props for S3 URI field in task definition of state machine for bedrock invoke model. | (fix) | | `false` | `true` |
| [@aws-cdk/core:aspectStabilization](#aws-cdkcoreaspectstabilization) | When enabled, a stabilization loop will be run when invoking Aspects during synthesis. | (config) | | `false` | `true` |
| [@aws-cdk/pipelines:reduceStageRoleTrustScope](#aws-cdkpipelinesreducestageroletrustscope) | Remove the root account principal from Stage addActions trust policy | (default) | | `false` | `true` |
<!-- END diff -->
Here is an example of a `cdk.json` file that restores v1 behavior for these flags:
<!-- BEGIN migratejson -->
```json
{
"context": {
"@aws-cdk/core:newStyleStackSynthesis": false,
"@aws-cdk/core:stackRelativeExports": false,
"@aws-cdk/aws-rds:lowercaseDbIdentifier": false,
"@aws-cdk/aws-apigateway:usagePlanKeyOrderInsensitiveId": false,
"@aws-cdk/aws-lambda:recognizeVersionProps": false,
"@aws-cdk/aws-cloudfront:defaultSecurityPolicyTLSv1.2_2021": false
}
}
```
<!-- END migratejson -->
## Feature flag details
Here are more details about each of the flags:
<!-- BEGIN details -->
### @aws-cdk/core:enableStackNameDuplicates
*Allow multiple stacks with the same name* (default)
If this is set, multiple stacks can use the same stack name (e.g. deployed to
different environments). This means that the name of the synthesized template
file will be based on the construct path and not on the defined `stackName`
of the stack.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.16.0 | `false` | `true` |
| (default in v2) | `true` | |
**Compatibility with old behavior:** Pass stack identifiers to the CLI instead of stack names.
### aws-cdk:enableDiffNoFail
*Make `cdk diff` not fail when there are differences* (default)
Determines what status code `cdk diff` should return when the specified stack
differs from the deployed stack or the local CloudFormation template:
* `aws-cdk:enableDiffNoFail=true` => status code == 0
* `aws-cdk:enableDiffNoFail=false` => status code == 1
You can override this behavior with the --fail flag:
* `--fail` => status code == 1
* `--no-fail` => status code == 0
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.19.0 | `false` | `true` |
| (default in v2) | `true` | |
**Compatibility with old behavior:** Specify `--fail` to the CLI.
### @aws-cdk/aws-ecr-assets:dockerIgnoreSupport
*DockerImageAsset properly supports `.dockerignore` files by default* (default)
If this flag is not set, the default behavior for `DockerImageAsset` is to use
glob semantics for `.dockerignore` files. If this flag is set, the default behavior
is standard Docker ignore semantics.
This is a feature flag as the old behavior was technically incorrect but
users may have come to depend on it.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.73.0 | `false` | `true` |
| (default in v2) | `true` | |
**Compatibility with old behavior:** Update your `.dockerignore` file to match standard Docker ignore rules, if necessary.
### @aws-cdk/aws-secretsmanager:parseOwnedSecretName
*Fix the referencing of SecretsManager names from ARNs* (default)
Secret.secretName for an "owned" secret will attempt to parse the secretName from the ARN,
rather than the default full resource name, which includes the SecretsManager suffix.
If this flag is not set, Secret.secretName will include the SecretsManager suffix, which cannot be directly
used by SecretsManager.DescribeSecret, and must be parsed by the user first (e.g., Fn:Join, Fn:Select, Fn:Split).
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.77.0 | `false` | `true` |
| (default in v2) | `true` | |
**Compatibility with old behavior:** Use `parseArn(secret.secretName).resourceName` to emulate the incorrect old parsing.
### @aws-cdk/aws-kms:defaultKeyPolicies
*Tighten default KMS key policies* (default)
KMS Keys start with a default key policy that grants the account access to administer the key,
mirroring the behavior of the KMS SDK/CLI/Console experience. Users may override the default key
policy by specifying their own.
If this flag is not set, the default key policy depends on the setting of the `trustAccountIdentities`
flag. If false (the default, for backwards-compatibility reasons), the default key policy somewhat
resembles the default admin key policy, but with the addition of 'GenerateDataKey' permissions. If
true, the policy matches what happens when this feature flag is set.
Additionally, if this flag is not set and the user supplies a custom key policy, this will be appended
to the key's default policy (rather than replacing it).
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.78.0 | `false` | `true` |
| (default in v2) | `true` | |
**Compatibility with old behavior:** Pass `trustAccountIdentities: false` to `Key` construct to restore the old behavior.
### @aws-cdk/aws-s3:grantWriteWithoutAcl
*Remove `PutObjectAcl` from Bucket.grantWrite* (default)
Change the old 's3:PutObject*' permission to 's3:PutObject' on Bucket,
as the former includes 's3:PutObjectAcl',
which could be used to grant read/write object access to IAM principals in other accounts.
Use a feature flag to make sure existing customers who might be relying
on the overly-broad permissions are not broken.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.85.0 | `false` | `true` |
| (default in v2) | `true` | |
**Compatibility with old behavior:** Call `bucket.grantPutAcl()` in addition to `bucket.grantWrite()` to grant ACL permissions.
### @aws-cdk/aws-ecs-patterns:removeDefaultDesiredCount
*Do not specify a default DesiredCount for ECS services* (default)
ApplicationLoadBalancedServiceBase, ApplicationMultipleTargetGroupServiceBase,
NetworkLoadBalancedServiceBase, NetworkMultipleTargetGroupServiceBase, and
QueueProcessingServiceBase currently determine a default value for the desired count of
a CfnService if a desiredCount is not provided. The result of this is that on every
deployment, the service count is reset to the fixed value, even if it was autoscaled.
If this flag is not set, the default behaviour for CfnService.desiredCount is to set a
desiredCount of 1, if one is not provided. If true, a default will not be defined for
CfnService.desiredCount and as such desiredCount will be undefined, if one is not provided.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.92.0 | `false` | `true` |
| (default in v2) | `true` | |
**Compatibility with old behavior:** You can pass `desiredCount: 1` explicitly, but you should never need this.
### @aws-cdk/aws-efs:defaultEncryptionAtRest
*Enable this feature flag to have elastic file systems encrypted at rest by default.* (default)
Encryption can also be configured explicitly using the `encrypted` property.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.98.0 | `false` | `true` |
| (default in v2) | `true` | |
**Compatibility with old behavior:** Pass the `encrypted: false` property to the `FileSystem` construct to disable encryption.
### @aws-cdk/core:newStyleStackSynthesis
*Switch to new stack synthesis method which enables CI/CD* (fix)
If this flag is specified, all `Stack`s will use the `DefaultStackSynthesizer` by
default. If it is not set, they will use the `LegacyStackSynthesizer`.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.39.0 | `false` | `true` |
| 2.0.0 | `true` | `true` |
### @aws-cdk/core:stackRelativeExports
*Name exports based on the construct paths relative to the stack, rather than the global construct path* (fix)
Combined with the stack name this relative construct path is good enough to
ensure uniqueness, and makes the export names robust against refactoring
the location of the stack in the construct tree (specifically, moving the Stack
into a Stage).
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.58.0 | `false` | `true` |
| 2.0.0 | `true` | `true` |
### @aws-cdk/aws-rds:lowercaseDbIdentifier
*Force lowercasing of RDS Cluster names in CDK* (fix)
Cluster names must be lowercase, and the service will lowercase the name when the cluster
is created. However, CDK did not use to know about this, and would use the user-provided name
referencing the cluster, which would fail if it happened to be mixed-case.
With this flag, lowercase the name in CDK so we can reference it properly.
Must be behind a permanent flag because changing a name from mixed case to lowercase between deployments
would lead CloudFormation to think the name was changed and would trigger a cluster replacement
(losing data!).
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.97.0 | `false` | `true` |
| 2.0.0 | `true` | `true` |
### @aws-cdk/aws-apigateway:usagePlanKeyOrderInsensitiveId
*Allow adding/removing multiple UsagePlanKeys independently* (fix)
The UsagePlanKey resource connects an ApiKey with a UsagePlan. API Gateway does not allow more than one UsagePlanKey
for any given UsagePlan and ApiKey combination. For this reason, CloudFormation cannot replace this resource without
either the UsagePlan or ApiKey changing.
The feature addition to support multiple UsagePlanKey resources - 142bd0e2 - recognized this and attempted to keep
existing UsagePlanKey logical ids unchanged.
However, this intentionally caused the logical id of the UsagePlanKey to be sensitive to order. That is, when
the 'first' UsagePlanKey resource is removed, the logical id of the 'second' assumes what was originally the 'first',
which again is disallowed.
In effect, there is no way to get out of this mess in a backwards compatible way, while supporting existing stacks.
This flag changes the logical id layout of UsagePlanKey to not be sensitive to order.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.98.0 | `false` | `true` |
| 2.0.0 | `true` | `true` |
### @aws-cdk/aws-lambda:recognizeVersionProps
*Enable this feature flag to opt in to the updated logical id calculation for Lambda Version created using the `fn.currentVersion`.* (fix)
The previous calculation incorrectly considered properties of the `AWS::Lambda::Function` resource that did
not constitute creating a new Version.
See 'currentVersion' section in the aws-lambda module's README for more details.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.106.0 | `false` | `true` |
| 2.0.0 | `true` | `true` |
### @aws-cdk/aws-cloudfront:defaultSecurityPolicyTLSv1.2_2021
*Enable this feature flag to have cloudfront distributions use the security policy TLSv1.2_2021 by default.* (fix)
The security policy can also be configured explicitly using the `minimumProtocolVersion` property.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.117.0 | `false` | `true` |
| 2.0.0 | `true` | `true` |
### @aws-cdk/core:target-partitions
*What regions to include in lookup tables of environment agnostic stacks* (config)
Has no effect on stacks that have a defined region, but will limit the amount
of unnecessary regions included in stacks without a known region.
The type of this value should be a list of strings.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.137.0 | `false` | `["aws","aws-cn"]` |
| 2.4.0 | `false` | `["aws","aws-cn"]` |
### @aws-cdk-containers/ecs-service-extensions:enableDefaultLogDriver
*ECS extensions will automatically add an `awslogs` driver if no logging is specified* (default)
Enable this feature flag to configure default logging behavior for the ECS Service Extensions. This will enable the
`awslogs` log driver for the application container of the service to send the container logs to CloudWatch Logs.
This is a feature flag as the new behavior provides a better default experience for the users.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.140.0 | `false` | `true` |
| 2.8.0 | `false` | `true` |
**Compatibility with old behavior:** Specify a log driver explicitly.
### @aws-cdk/aws-ec2:uniqueImdsv2TemplateName
*Enable this feature flag to have Launch Templates generated by the `InstanceRequireImdsv2Aspect` use unique names.* (fix)
Previously, the generated Launch Template names were only unique within a stack because they were based only on the
`Instance` construct ID. If another stack that has an `Instance` with the same construct ID is deployed in the same
account and region, the deployments would always fail as the generated Launch Template names were the same.
The new implementation addresses this issue by generating the Launch Template name with the `Names.uniqueId` method.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.140.0 | `false` | `true` |
| 2.8.0 | `false` | `true` |
### @aws-cdk/aws-iam:minimizePolicies
*Minimize IAM policies by combining Statements* (config)
Minimize IAM policies by combining Principals, Actions and Resources of two
Statements in the policies, as long as it doesn't change the meaning of the
policy.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.150.0 | `false` | `true` |
| 2.18.0 | `false` | `true` |
### @aws-cdk/core:checkSecretUsage
*Enable this flag to make it impossible to accidentally use SecretValues in unsafe locations* (config)
With this flag enabled, `SecretValue` instances can only be passed to
constructs that accept `SecretValue`s; otherwise, `unsafeUnwrap()` must be
called to use it as a regular string.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.153.0 | `false` | `true` |
| 2.21.0 | `false` | `true` |
### @aws-cdk/aws-lambda:recognizeLayerVersion
*Enable this feature flag to opt in to the updated logical id calculation for Lambda Version created using the `fn.currentVersion`.* (fix)
This flag correct incorporates Lambda Layer properties into the Lambda Function Version.
See 'currentVersion' section in the aws-lambda module's README for more details.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| 1.159.0 | `false` | `true` |
| 2.27.0 | `false` | `true` |
### @aws-cdk/core:validateSnapshotRemovalPolicy
*Error on snapshot removal policies on resources that do not support it.* (default)
Makes sure we do not allow snapshot removal policy on resources that do not support it.
If supplied on an unsupported resource, CloudFormation ignores the policy altogether.
This flag will reduce confusion and unexpected loss of data when erroneously supplying
the snapshot removal policy.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.28.0 | `false` | `true` |
**Compatibility with old behavior:** The old behavior was incorrect. Update your source to not specify SNAPSHOT policies on resources that do not support it.
### @aws-cdk/aws-codepipeline:crossAccountKeyAliasStackSafeResourceName
*Generate key aliases that include the stack name* (fix)
Enable this feature flag to have CodePipeline generate a unique cross account key alias name using the stack name.
Previously, when creating multiple pipelines with similar naming conventions and when crossAccountKeys is true,
the KMS key alias name created for these pipelines may be the same due to how the uniqueId is generated.
This new implementation creates a stack safe resource name for the alias using the stack name instead of the stack ID.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.29.0 | `false` | `true` |
### @aws-cdk/aws-s3:createDefaultLoggingPolicy
*Enable this feature flag to create an S3 bucket policy by default in cases where an AWS service would automatically create the Policy if one does not exist.* (fix)
For example, in order to send VPC flow logs to an S3 bucket, there is a specific Bucket Policy
that needs to be attached to the bucket. If you create the bucket without a policy and then add the
bucket as the flow log destination, the service will automatically create the bucket policy with the
necessary permissions. If you were to then try and add your own bucket policy CloudFormation will throw
and error indicating that a bucket policy already exists.
In cases where we know what the required policy is we can go ahead and create the policy so we can
remain in control of it.
@see https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/AWS-logs-and-resource-policy.html#AWS-logs-infrastructure-S3
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.31.0 | `false` | `true` |
### @aws-cdk/aws-sns-subscriptions:restrictSqsDescryption
*Restrict KMS key policy for encrypted Queues a bit more* (fix)
Enable this feature flag to restrict the decryption of a SQS queue, which is subscribed to a SNS topic, to
only the topic which it is subscribed to and not the whole SNS service of an account.
Previously the decryption was only restricted to the SNS service principal. To make the SQS subscription more
secure, it is a good practice to restrict the decryption further and only allow the connected SNS topic to decryption
the subscribed queue.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.32.0 | `false` | `true` |
### @aws-cdk/aws-ecs:arnFormatIncludesClusterName
*ARN format used by ECS. In the new ARN format, the cluster name is part of the resource ID.* (fix)
If this flag is not set, the old ARN format (without cluster name) for ECS is used.
If this flag is set, the new ARN format (with cluster name) for ECS is used.
This is a feature flag as the old format is still valid for existing ECS clusters.
See https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ecs-account-settings.html#ecs-resource-ids
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.35.0 | `false` | `true` |
### @aws-cdk/aws-apigateway:disableCloudWatchRole
*Make default CloudWatch Role behavior safe for multiple API Gateways in one environment* (fix)
Enable this feature flag to change the default behavior for aws-apigateway.RestApi and aws-apigateway.SpecRestApi
to _not_ create a CloudWatch role and Account. There is only a single ApiGateway account per AWS
environment which means that each time you create a RestApi in your account the ApiGateway account
is overwritten. If at some point the newest RestApi is deleted, the ApiGateway Account and CloudWatch
role will also be deleted, breaking any existing ApiGateways that were depending on them.
When this flag is enabled you should either create the ApiGateway account and CloudWatch role
separately _or_ only enable the cloudWatchRole on a single RestApi.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.38.0 | `false` | `true` |
### @aws-cdk/core:enablePartitionLiterals
*Make ARNs concrete if AWS partition is known* (fix)
Enable this feature flag to get partition names as string literals in Stacks with known regions defined in
their environment, such as "aws" or "aws-cn". Previously the CloudFormation intrinsic function
"Ref: AWS::Partition" was used. For example:
```yaml
Principal:
AWS:
Fn::Join:
- ""
- - "arn:"
- Ref: AWS::Partition
- :iam::123456789876:root
```
becomes:
```yaml
Principal:
AWS: "arn:aws:iam::123456789876:root"
```
The intrinsic function will still be used in Stacks where no region is defined or the region's partition
is unknown.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.38.0 | `false` | `true` |
### @aws-cdk/aws-ecs:disableExplicitDeploymentControllerForCircuitBreaker
*Avoid setting the "ECS" deployment controller when adding a circuit breaker* (fix)
Enable this feature flag to avoid setting the "ECS" deployment controller when adding a circuit breaker to an
ECS Service, as this will trigger a full replacement which fails to deploy when using set service names.
This does not change any behaviour as the default deployment controller when it is not defined is ECS.
This is a feature flag as the new behavior provides a better default experience for the users.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.51.0 | `false` | `true` |
### @aws-cdk/aws-events:eventsTargetQueueSameAccount
*Event Rules may only push to encrypted SQS queues in the same account* (fix)
This flag applies to SQS Queues that are used as the target of event Rules. When enabled, only principals
from the same account as the Rule can send messages. If a queue is unencrypted, this restriction will
always apply, regardless of the value of this flag.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.51.0 | `false` | `true` |
### @aws-cdk/aws-iam:importedRoleStackSafeDefaultPolicyName
*Enable this feature to by default create default policy names for imported roles that depend on the stack the role is in.* (fix)
Without this, importing the same role in multiple places could lead to the permissions given for one version of the imported role
to overwrite permissions given to the role at a different place where it was imported. This was due to all imported instances
of a role using the same default policy name.
This new implementation creates default policy names based on the constructs node path in their stack.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.60.0 | `false` | `true` |
### @aws-cdk/aws-s3:serverAccessLogsUseBucketPolicy
*Use S3 Bucket Policy instead of ACLs for Server Access Logging* (fix)
Enable this feature flag to use S3 Bucket Policy for granting permission fo Server Access Logging
rather than using the canned `LogDeliveryWrite` ACL. ACLs do not work when Object Ownership is
enabled on the bucket.
This flag uses a Bucket Policy statement to allow Server Access Log delivery, following best
practices for S3.
@see https://docs.aws.amazon.com/AmazonS3/latest/userguide/enable-server-access-logging.html
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.60.0 | `false` | `true` |
### @aws-cdk/customresources:installLatestAwsSdkDefault
*Whether to install the latest SDK by default in AwsCustomResource* (default)
This was originally introduced and enabled by default to not be limited by the SDK version
that's installed on AWS Lambda. However, it creates issues for Lambdas bound to VPCs that
do not have internet access, or in environments where 'npmjs.com' is not available.
The recommended setting is to disable the default installation behavior, and pass the
flag on a resource-by-resource basis to enable it if necessary.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.60.0 | `false` | `false` |
**Compatibility with old behavior:** Set installLatestAwsSdk: true on all resources that need it.
### @aws-cdk/aws-route53-patters:useCertificate
*Use the official `Certificate` resource instead of `DnsValidatedCertificate`* (default)
Enable this feature flag to use the official CloudFormation supported `Certificate` resource instead
of the deprecated `DnsValidatedCertificate` construct. If this flag is enabled and you are creating
the stack in a region other than us-east-1 then you must also set `crossRegionReferences=true` on the
stack.
| Since | Default | Recommended |
| ----- | ----- | ----- |
| (not in v1) | | |
| 2.61.0 | `false` | `true` |
**Compa