The Cloudformation resources AWS::Cloudformation::WaitCondition and AWS::Cloudformation::WaitConditionHandle cannot currently be updated or recreated. To wait for resource signaling during a stack update a new WaitCondition resource needs to be created. This macro will create new WaitCondition resources based on changes to specified parameters.

# Unit Test
python3 -m unittest

Set any required AWS CLI env variables. http://docs.aws.amazon.com/cli/latest/userguide/cli-environment.html

./build.sh

aws cloudformation package \
  --template deploy-macro.yaml \
  --s3-bucket <YOUR S3 BUCKET> \
  --output-template-file packaged-deploy-macro.yaml

aws cloudformation deploy \
  --template-file packaged-deploy-macro.yaml \
  --stack-name cloudformation-macro-WaitConditionUpdate \
  --capabilities CAPABILITY_IAM

Your template must have contain the parameter WaitConditionUpdateParameters and Transform. When the parameters of WaitConditionUpdateParameters change the logical ids of all WaitCondition resources will be renamed.

Transform: ['WaitConditionUpdate']
Parameters:
  WaitConditionUpdateParameters:
    Description: Used by the WaitConditionUpdate transform macro to determine which
      parameter values will be used for naming any WaitCondition resources.  The 
      parameters must only be those which will trigger a recreation of the signaling
      resource when changed.
    Type: CommaDelimitedList
    Default: "PutDefaultsHere"

Use a WaitCondition to get a signal when tasks are healthy in a ECS Service

example-ecs-service.yaml