Unit testing for replacement of stateful resources

[alex5207]

Hi,

I've been reading about the built-in functionality of aws-cdk.assertions to test various properties about the resources that has been created. I am looking for a neat way to unit test that the changes I made to my code does not cause a replacement in my stateful resources like S3 buckets and DynamoDB tables.

I haven't found any documentation for doing so. Can I somehow assert that the synthesized template does not cause a replacement for particular resources?

[peterwoodworth]

@github-actions proposed-answer Unit tests will test that a template is generated a certain way. Given a construct StatefulConstruct that creates both a Bucket and a Table, you could write unit tests that verify when you instantiate StatefulConstruct in a stack, a Bucket and Table resource are created with XYZ properties. View this section of the CDK workshop to see how you might create tests. The properties that you want to test for sure are the properties in the CloudFormation document that are marked as Update requires: Replacement

If you make changes to your StatefulConstruct construct such that these unit tests will start producing different values for any resources marked as Update requires: Replacement, then your unit tests should catch this.

[github-actions[bot]]

Hello! A team member has marked the above comment as the likely answer to this discussion thread. If you agree, please upvote that comment, or click on Mark as answer. I will automatically mark the comment as the answer next time I check. If this answer does not help you, please downvote the answer instead and let us know why it was not helpful. I will add a label to this discussion to gain attention from the team.

[alex5207]

Thank you, Peter! Very helpful

[github-actions[bot]]

Hello! Reopening this discussion to make it searchable.