AWS CloudFormation template that checks if a mapping value is still set to the default/example value, and if so, forces stack creation to fail

cloudformation-force-failure-if-mapping-still-set-to-default.yml

AWSTemplateFormatVersion: 2010-09-09
Description: Example ensuring mapping isn't set to it's default
Mappings:
  Variables:
    AnExampleKey:
      # Make sure to set AnExampleVariable before launching this stack
      AnExampleVariable: arn:aws:iam::123456789012:root
Conditions:
  VariablesNotSet: !Equals [ !FindInMap [ Variables, AnExampleKey, AnExampleVariable ] , 'arn:aws:iam::123456789012:root' ]
Resources:
  # If the Mapping variables haven't been set and are still the example values
  # fail the creation of the stack by timing out this WaitCondition
  VariablesAreNotConfiguredWaitConditionHandle:
    Type: AWS::CloudFormation::WaitConditionHandle
    Condition: VariablesNotSet
  VariablesAreNotConfiguredWaitCondition:
    Type: AWS::CloudFormation::WaitCondition
    Condition: VariablesNotSet
    Properties:
      Handle: !Ref VariablesAreNotConfiguredWaitConditionHandle
      Timeout: "1"
  TestTopic:
    Type: AWS::SNS::Topic
    Properties:
      DisplayName: A test sns topic
      TopicName: TestSNSTopic