ResourceChangeDetail¶

The identity of the entity that triggered this change. This entity is a member of the group that's specified by the ChangeSource field. For example, if you modified the value of the KeyPairName parameter, the CausingEntity is the name of the parameter (KeyPairName).

If the ChangeSource value is DirectModification, no value is given for CausingEntity.

The group to which the CausingEntity value belongs. There are five entity groups:

• ResourceReference entities are Ref intrinsic functions that refer to resources in the template, such as { "Ref" : "MyEC2InstanceResource" }.

• ParameterReference entities are Ref intrinsic functions that get template parameter values, such as { "Ref" : "MyPasswordParameter" }.

• ResourceAttribute entities are Fn::GetAtt intrinsic functions that get resource attribute values, such as { "Fn::GetAtt" : [ "MyEC2InstanceResource", "PublicDnsName" ] }.

• DirectModification entities are changes that are made directly to the template.

• Automatic entities are AWS::CloudFormation::Stack resource types, which are also known as nested stacks. If you made no changes to the AWS::CloudFormation::Stack resource, CloudFormation sets the ChangeSource to Automatic because the nested stack's template might have changed. Changes to a nested stack's template aren't visible to CloudFormation until you run an update on the parent stack.

• NoModification entities are changes made to the template that matches the actual state of the resource.

Indicates whether CloudFormation can determine the target value, and whether the target value will change before you execute a change set.

For Static evaluations, CloudFormation can determine that the target value will change, and its value. For example, if you directly modify the InstanceType property of an EC2 instance, CloudFormation knows that this property value will change, and its value, so this is a Static evaluation.

For Dynamic evaluations, can't determine the target value because it depends on the result of an intrinsic function, such as a Ref or Fn::GetAtt intrinsic function, when the stack is updated. For example, if your template includes a reference to a resource that's conditionally recreated, the value of the reference (the physical ID of the resource) might change, depending on if the resource is recreated. If the resource is recreated, it will have a new physical ID, so all references to that resource will also be updated.

A ResourceTargetDefinition structure that describes the field that CloudFormation will change and whether the resource will be recreated.