AWS::CloudFormation::WaitConditionHandle - Amazon CloudFormation
SyntaxReturn valuesSee also
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AWS::CloudFormation::WaitConditionHandle

Important

For Amazon EC2 and Auto Scaling resources, we recommend that you use a CreationPolicy attribute instead of wait conditions. Add a CreationPolicy attribute to those resources, and use the cfn-signal helper script to signal when an instance creation process has completed successfully.

For more information, see Deploying applications on Amazon EC2 with Amazon CloudFormation.

The AWS::CloudFormation::WaitConditionHandle type has no properties. When you reference the WaitConditionHandle resource by using the Ref function, Amazon CloudFormation returns a presigned URL. You pass this URL to applications or scripts that are running on your Amazon EC2 instances to send signals to that URL. An associated AWS::CloudFormation::WaitCondition resource checks the URL for the required number of success signals or for a failure signal.

Important

Anytime you add a WaitCondition resource during a stack update or update a resource with a wait condition, you must associate the wait condition with a new WaitConditionHandle resource. Don't reuse an old wait condition handle that has already been defined in the template. If you reuse a wait condition handle, the wait condition might evaluate old signals from a previous create or update stack command.

Note

Updates aren't supported for this resource.

Syntax

To declare this entity in your Amazon CloudFormation template, use the following syntax:

JSON

{
  "Type" : "AWS::CloudFormation::WaitConditionHandle
}

YAML

Type: AWS::CloudFormation::WaitConditionHandle

Return values

Fn::GetAtt

The Fn::GetAtt intrinsic function returns a value for a specified attribute of this type. The following are the available attributes and sample return values.

For more information about using the Fn::GetAtt intrinsic function, see Fn::GetAtt.

Id

A unique identifier for the resource.

See also