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 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.
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. Do not 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 are not 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:
Related Resources
For information about how to use wait conditions, see Creating Wait Conditions in a Template.
