(assert): there should be something like ```haveManifest(...)``` and ```haveHelmChart``` or a matcher like ```k8sobjectlike``` that allow unit tests for kubernetes objects

Description

It would be nice if we could write unit tests for eks components like helmcharts and manifests. These resources contain JSON objects (the kubernetes manifests or helmchart values) that are stringified via:

/**
   * Convert an object, potentially containing tokens, to a JSON string
   */
public toJsonString(obj: any, space?: number): string {
  return CloudFormationLang.toJSON(obj, space).toString();
}

It would be nice if this would be parsed and then could be used with matchers like objectLike or arrayWith

Use Case

I want to create unit tests for constructs that contain kubernetes resources. At the moment it’s not possible or I didn’t found the docs how to do this.

I only find examples that do something like:

expect(stack).toHaveResource(KubernetesManifest.RESOURCE_TYPE, {
  Manifest: JSON.stringify([
    {
      apiVersion: 'v1beta',
      kind: 'Foo',
      metadata: {
        labels: {
          'aws.cdk.eks/prune-c89a5983505f58231ac2a9a86fd82735ccf2308eac': '',
        },
      },
    },
  ]),
  PruneLabel: 'aws.cdk.eks/prune-c89a5983505f58231ac2a9a86fd82735ccf2308eac',
});

but I would like to have something like:

expect(stack).toHaveManifest('SomeIdentifier?', {
  Manifest: arrayWith(
    {
      apiVersion: 'v1beta',
      kind: 'Foo',
      ...
      anything: objectLike({
        some: 'value'
      }
    },
  ]),
...
});

Proposed Solution

I have no Idea at the moment… somehow we have to JSON parse the stringified k8s objects

Other information

no

Acknowledge

• I may be able to implement this feature request
• This feature might incur a breaking change

[markussiebert]

Looks perfect! Will give it a try tomorrow!

[markussiebert]

only for others who stumble over this: works like a charm!