more doc changes

docs/utilities/custom_resources.md

@@ -45,7 +45,7 @@ Inside the methods, implement your custom provisioning logic, and return a `Resp
 
 Custom resources notify cloudformation either of `SUCCESS` or `FAILED` status. You have 2 utility methods to represent these responses: `Response.success(physicalResourceId)` and `Response.failed(physicalResourceId)`. 
 The `physicalResourceId` is an identifier that is used during the lifecycle operations of the Custom Resource. 
-You should supply a `physicalResourceId` during the `CREATE` operation, CloudFormation stores the `physicalResourceId` and includes it `UPDATE` and `DELETE` events.
+You should generate a `physicalResourceId` during the `CREATE` operation, CloudFormation stores the `physicalResourceId` and includes it `UPDATE` and `DELETE` events.
 
 Here an example of how to implement a Custom Resource using the powertools-cloudformation library:
 
@@ -167,7 +167,10 @@ with the Fn::GetAtt function.
 public class SensitiveDataHandler extends AbstractResourceHandler {
  @Override
  protected Response create(CloudFormationCustomResourceEvent createEvent, Context context) {
+ String physicalResourceId = "my-sensitive-resource-" + UUID.randomUUID(); //Create a unique ID 
  return Response.builder()
+ .status(Response.Status.SUCCESS)
+ .physicalResourceId(physicalResourceId)
  .value(Map.of("SomeSecret", sensitiveValue))
  .noEcho(true)
  .build();
@@ -201,8 +204,11 @@ public class CustomSerializationHandler extends AbstractResourceHandler {
 
  @Override
  protected Response create(CloudFormationCustomResourceEvent createEvent, Context context) {
+ String physicalResourceId = "my-policy-name-" + UUID.randomUUID(); //Create a unique ID 
  Policy policy = new Policy();
  return Response.builder()
+ .status(Response.Status.SUCCESS)
+ .physicalResourceId(physicalResourceId)
  .value(policy)
  .objectMapper(policyMapper) // customize serialization
  .build();