class CfnWarmPool (construct)

Language	Type name
.NET	Amazon.CDK.AWS.AutoScaling.CfnWarmPool
Go	github.com/aws/aws-cdk-go/awscdk/v2/awsautoscaling#CfnWarmPool
Java	software.amazon.awscdk.services.autoscaling.CfnWarmPool
Python	aws_cdk.aws_autoscaling.CfnWarmPool
TypeScript	aws-cdk-lib » aws_autoscaling » CfnWarmPool

Implements IConstruct, IDependable, IInspectable

The AWS::AutoScaling::WarmPool resource creates a pool of pre-initialized EC2 instances that sits alongside the Auto Scaling group.

Whenever your application needs to scale out, the Auto Scaling group can draw on the warm pool to meet its new desired capacity.

When you create a warm pool, you can define a minimum size. When your Auto Scaling group scales out and the size of the warm pool shrinks, Amazon EC2 Auto Scaling launches new instances into the warm pool to maintain its minimum size.

For more information, see Warm pools for Amazon EC2 Auto Scaling in the Amazon EC2 Auto Scaling User Guide .

CloudFormation supports the UpdatePolicy attribute for Auto Scaling groups. During an update, if UpdatePolicy is set to AutoScalingRollingUpdate , CloudFormation replaces InService instances only. Instances in the warm pool are not replaced. The difference in which instances are replaced can potentially result in different instance configurations after the stack update completes. If UpdatePolicy is set to AutoScalingReplacingUpdate , you do not encounter this issue because CloudFormation replaces both the Auto Scaling group and the warm pool.

See also: http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-autoscaling-warmpool.html

Example

// The code below shows an example of how to instantiate this type.
// The values are placeholders you should change.
import { aws_autoscaling as autoscaling } from 'aws-cdk-lib';
const cfnWarmPool = new autoscaling.CfnWarmPool(this, 'MyCfnWarmPool', {
  autoScalingGroupName: 'autoScalingGroupName',

  // the properties below are optional
  instanceReusePolicy: {
    reuseOnScaleIn: false,
  },
  maxGroupPreparedCapacity: 123,
  minSize: 123,
  poolState: 'poolState',
});

Initializer

new CfnWarmPool(scope: Construct, id: string, props: CfnWarmPoolProps)

Parameters

• scope Construct — Scope in which this resource is defined.
• id string — Construct identifier for this resource (unique in its scope).
• props CfnWarmPoolProps — Resource properties.

Construct Props

Name	Type	Description
autoScalingGroupName	string	The name of the Auto Scaling group.
instanceReusePolicy?	IResolvable | InstanceReusePolicyProperty	Indicates whether instances in the Auto Scaling group can be returned to the warm pool on scale in.
maxGroupPreparedCapacity?	number	Specifies the maximum number of instances that are allowed to be in the warm pool or in any state except Terminated for the Auto Scaling group.
minSize?	number	Specifies the minimum number of instances to maintain in the warm pool.
poolState?	string	Sets the instance state to transition to after the lifecycle actions are complete.

---

autoScalingGroupName

Type: string

The name of the Auto Scaling group.

See also: http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-autoscaling-warmpool.html#cfn-autoscaling-warmpool-autoscalinggroupname

---

instanceReusePolicy?

Type: IResolvable | InstanceReusePolicyProperty (optional)

Indicates whether instances in the Auto Scaling group can be returned to the warm pool on scale in.

The default is to terminate instances in the Auto Scaling group when the group scales in.

See also: http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-autoscaling-warmpool.html#cfn-autoscaling-warmpool-instancereusepolicy

---

maxGroupPreparedCapacity?

Type: number (optional)

Specifies the maximum number of instances that are allowed to be in the warm pool or in any state except Terminated for the Auto Scaling group.

This is an optional property. Specify it only if you do not want the warm pool size to be determined by the difference between the group's maximum capacity and its desired capacity.

If a value for MaxGroupPreparedCapacity is not specified, Amazon EC2 Auto Scaling launches and maintains the difference between the group's maximum capacity and its desired capacity. If you specify a value for MaxGroupPreparedCapacity , Amazon EC2 Auto Scaling uses the difference between the MaxGroupPreparedCapacity and the desired capacity instead.

The size of the warm pool is dynamic. Only when MaxGroupPreparedCapacity and MinSize are set to the same value does the warm pool have an absolute size.

If the desired capacity of the Auto Scaling group is higher than the MaxGroupPreparedCapacity , the capacity of the warm pool is 0, unless you specify a value for MinSize . To remove a value that you previously set, include the property but specify -1 for the value.

See also: http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-autoscaling-warmpool.html#cfn-autoscaling-warmpool-maxgrouppreparedcapacity

---

minSize?

Type: number (optional)

Specifies the minimum number of instances to maintain in the warm pool.

This helps you to ensure that there is always a certain number of warmed instances available to handle traffic spikes. Defaults to 0 if not specified.

See also: http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-autoscaling-warmpool.html#cfn-autoscaling-warmpool-minsize

---

poolState?

Type: string (optional)

Sets the instance state to transition to after the lifecycle actions are complete.

Default is Stopped .

See also: http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-autoscaling-warmpool.html#cfn-autoscaling-warmpool-poolstate

Properties

Name	Type	Description
autoScalingGroupName	string	The name of the Auto Scaling group.
cfnOptions	ICfnResourceOptions	Options for this resource, such as condition, update policy etc.
cfnProperties	{ [string]: any }
cfnResourceType	string	AWS resource type.
creationStack	string[]
logicalId	string	The logical ID for this CloudFormation stack element.
node	Node	The tree node.
ref	string	Return a string that will be resolved to a CloudFormation { Ref } for this element.
stack	Stack	The stack in which this element is defined.
instanceReusePolicy?	IResolvable | InstanceReusePolicyProperty	Indicates whether instances in the Auto Scaling group can be returned to the warm pool on scale in.
maxGroupPreparedCapacity?	number	Specifies the maximum number of instances that are allowed to be in the warm pool or in any state except Terminated for the Auto Scaling group.
minSize?	number	Specifies the minimum number of instances to maintain in the warm pool.
poolState?	string	Sets the instance state to transition to after the lifecycle actions are complete.
static CFN_RESOURCE_TYPE_NAME	string	The CloudFormation resource type name for this resource class.

---

autoScalingGroupName

Type: string

The name of the Auto Scaling group.

---

cfnOptions

Type: ICfnResourceOptions

Options for this resource, such as condition, update policy etc.

---

cfnProperties

Type: { [string]: any }

---

cfnResourceType

Type: string

AWS resource type.

---

creationStack

Type: string[]

---

logicalId

Type: string

The logical ID for this CloudFormation stack element.

The logical ID of the element is calculated from the path of the resource node in the construct tree.

To override this value, use overrideLogicalId(newLogicalId).

---

node

Type: Node

The tree node.

---

ref

Type: string

Return a string that will be resolved to a CloudFormation { Ref } for this element.

If, by any chance, the intrinsic reference of a resource is not a string, you could coerce it to an IResolvable through Lazy.any({ produce: resource.ref }).

---

stack

Type: Stack

The stack in which this element is defined.

CfnElements must be defined within a stack scope (directly or indirectly).

---

instanceReusePolicy?

Type: IResolvable | InstanceReusePolicyProperty (optional)

Indicates whether instances in the Auto Scaling group can be returned to the warm pool on scale in.

---

maxGroupPreparedCapacity?

Type: number (optional)

Specifies the maximum number of instances that are allowed to be in the warm pool or in any state except Terminated for the Auto Scaling group.

---

minSize?

Type: number (optional)

Specifies the minimum number of instances to maintain in the warm pool.

---

poolState?

Type: string (optional)

Sets the instance state to transition to after the lifecycle actions are complete.

---

static CFN_RESOURCE_TYPE_NAME

Type: string

The CloudFormation resource type name for this resource class.

Methods

Name	Description
addDeletionOverride(path)	Syntactic sugar for addOverride(path, undefined).
addDependency(target)	Indicates that this resource depends on another resource and cannot be provisioned unless the other resource has been successfully provisioned.
addDependsOn(target)⚠️	Indicates that this resource depends on another resource and cannot be provisioned unless the other resource has been successfully provisioned.
addMetadata(key, value)	Add a value to the CloudFormation Resource Metadata.
addOverride(path, value)	Adds an override to the synthesized CloudFormation resource.
addPropertyDeletionOverride(propertyPath)	Adds an override that deletes the value of a property from the resource definition.
addPropertyOverride(propertyPath, value)	Adds an override to a resource property.
applyRemovalPolicy(policy?, options?)	Sets the deletion policy of the resource based on the removal policy specified.
getAtt(attributeName, typeHint?)	Returns a token for an runtime attribute of this resource.
getMetadata(key)	Retrieve a value value from the CloudFormation Resource Metadata.
inspect(inspector)	Examines the CloudFormation resource and discloses attributes.
obtainDependencies()	Retrieves an array of resources this resource depends on.
obtainResourceDependencies()	Get a shallow copy of dependencies between this resource and other resources in the same stack.
overrideLogicalId(newLogicalId)	Overrides the auto-generated logical ID with a specific ID.
removeDependency(target)	Indicates that this resource no longer depends on another resource.
replaceDependency(target, newTarget)	Replaces one dependency with another.
toString()	Returns a string representation of this construct.
protected renderProperties(props)

---

addDeletionOverride(path)

public addDeletionOverride(path: string): void

Parameters

• path string — The path of the value to delete.

Syntactic sugar for addOverride(path, undefined).

---

addDependency(target)

public addDependency(target: CfnResource): void

Parameters

• target CfnResource

Indicates that this resource depends on another resource and cannot be provisioned unless the other resource has been successfully provisioned.

This can be used for resources across stacks (or nested stack) boundaries and the dependency will automatically be transferred to the relevant scope.

---

addDependsOn(target)⚠️

public addDependsOn(target: CfnResource): void

⚠️ Deprecated: use addDependency

Parameters

• target CfnResource

Indicates that this resource depends on another resource and cannot be provisioned unless the other resource has been successfully provisioned.

---

addMetadata(key, value)

public addMetadata(key: string, value: any): void

Parameters

• key string
• value any

Add a value to the CloudFormation Resource Metadata.

See also: [https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/metadata-section-structure.html

Note that this is a different set of metadata from CDK node metadata; this metadata ends up in the stack template under the resource, whereas CDK node metadata ends up in the Cloud Assembly.](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/metadata-section-structure.html

Note that this is a different set of metadata from CDK node metadata; this metadata ends up in the stack template under the resource, whereas CDK node metadata ends up in the Cloud Assembly.)

---

addOverride(path, value)

public addOverride(path: string, value: any): void

Parameters

• path string — - The path of the property, you can use dot notation to override values in complex types.
• value any — - The value.

Adds an override to the synthesized CloudFormation resource.

To add a property override, either use addPropertyOverride or prefix path with "Properties." (i.e. Properties.TopicName).

If the override is nested, separate each nested level using a dot (.) in the path parameter. If there is an array as part of the nesting, specify the index in the path.

To include a literal . in the property name, prefix with a \. In most programming languages you will need to write this as "\\." because the \ itself will need to be escaped.

For example,

cfnResource.addOverride('Properties.GlobalSecondaryIndexes.0.Projection.NonKeyAttributes', ['myattribute']);
cfnResource.addOverride('Properties.GlobalSecondaryIndexes.1.ProjectionType', 'INCLUDE');

would add the overrides

"Properties": {
  "GlobalSecondaryIndexes": [
    {
      "Projection": {
        "NonKeyAttributes": [ "myattribute" ]
        ...
      }
      ...
    },
    {
      "ProjectionType": "INCLUDE"
      ...
    },
  ]
  ...
}

The value argument to addOverride will not be processed or translated in any way. Pass raw JSON values in here with the correct capitalization for CloudFormation. If you pass CDK classes or structs, they will be rendered with lowercased key names, and CloudFormation will reject the template.

---

addPropertyDeletionOverride(propertyPath)

public addPropertyDeletionOverride(propertyPath: string): void

Parameters

• propertyPath string — The path to the property.

Adds an override that deletes the value of a property from the resource definition.

---

addPropertyOverride(propertyPath, value)

public addPropertyOverride(propertyPath: string, value: any): void

Parameters

• propertyPath string — The path of the property.
• value any — The value.

Adds an override to a resource property.

Syntactic sugar for addOverride("Properties.<...>", value).

---

applyRemovalPolicy(policy?, options?)

public applyRemovalPolicy(policy?: RemovalPolicy, options?: RemovalPolicyOptions): void

Parameters

• policy RemovalPolicy
• options RemovalPolicyOptions

Sets the deletion policy of the resource based on the removal policy specified.

The Removal Policy controls what happens to this resource when it stops being managed by CloudFormation, either because you've removed it from the CDK application or because you've made a change that requires the resource to be replaced.

The resource can be deleted (RemovalPolicy.DESTROY), or left in your AWS account for data recovery and cleanup later (RemovalPolicy.RETAIN). In some cases, a snapshot can be taken of the resource prior to deletion (RemovalPolicy.SNAPSHOT). A list of resources that support this policy can be found in the following link:

See also: https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-attribute-deletionpolicy.html#aws-attribute-deletionpolicy-options

---

getAtt(attributeName, typeHint?)

public getAtt(attributeName: string, typeHint?: ResolutionTypeHint): Reference

Parameters

• attributeName string — The name of the attribute.
• typeHint ResolutionTypeHint

Returns

• Reference

Returns a token for an runtime attribute of this resource.

Ideally, use generated attribute accessors (e.g. resource.arn), but this can be used for future compatibility in case there is no generated attribute.

---

getMetadata(key)

public getMetadata(key: string): any

Parameters

• key string

Returns

• any

Retrieve a value value from the CloudFormation Resource Metadata.

See also: [https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/metadata-section-structure.html

Note that this is a different set of metadata from CDK node metadata; this metadata ends up in the stack template under the resource, whereas CDK node metadata ends up in the Cloud Assembly.](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/metadata-section-structure.html

Note that this is a different set of metadata from CDK node metadata; this metadata ends up in the stack template under the resource, whereas CDK node metadata ends up in the Cloud Assembly.)

---

inspect(inspector)

public inspect(inspector: TreeInspector): void

Parameters

• inspector TreeInspector — tree inspector to collect and process attributes.

Examines the CloudFormation resource and discloses attributes.

---

obtainDependencies()

public obtainDependencies(): Stack | CfnResource[]

Returns

• Stack | CfnResource[]

Retrieves an array of resources this resource depends on.

This assembles dependencies on resources across stacks (including nested stacks) automatically.

---

obtainResourceDependencies()

public obtainResourceDependencies(): CfnResource[]

Returns

• CfnResource[]

Get a shallow copy of dependencies between this resource and other resources in the same stack.

---

overrideLogicalId(newLogicalId)

public overrideLogicalId(newLogicalId: string): void

Parameters

• newLogicalId string — The new logical ID to use for this stack element.

Overrides the auto-generated logical ID with a specific ID.

---

removeDependency(target)

public removeDependency(target: CfnResource): void

Parameters

• target CfnResource

Indicates that this resource no longer depends on another resource.

This can be used for resources across stacks (including nested stacks) and the dependency will automatically be removed from the relevant scope.

---

replaceDependency(target, newTarget)

public replaceDependency(target: CfnResource, newTarget: CfnResource): void

Parameters

• target CfnResource — The dependency to replace.
• newTarget CfnResource — The new dependency to add.

Replaces one dependency with another.

---

toString()

public toString(): string

Returns

• string

Returns a string representation of this construct.

---

protected renderProperties(props)

protected renderProperties(props: { [string]: any }): { [string]: any }

Parameters

• props { [string]: any }

Returns

• { [string]: any }