AWS::CloudFormation::WaitConditionHandle
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 AWS CloudFormation.
The AWS::CloudFormation::WaitConditionHandle
type has no properties. When you reference the
WaitConditionHandle
resource by using the Ref function, AWS 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.
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.
Updates aren't supported for this resource.
Syntax
To declare this entity in your AWS CloudFormation template, use the following syntax:
JSON
{ "Type" : "AWS::CloudFormation::WaitConditionHandle", "Properties" : { } }
YAML
Type: AWS::CloudFormation::WaitConditionHandle Properties:
See also
-
For information about how to use wait conditions, see Creating wait conditions in a template.