[Proposal] Enable Lombok.toBuilder annotation flag in ResourceModel template

Comece por python/rpdk/java/templates/init/guided_aws/ResourceModel.java, vinculado na issue, e examine como as anotações de ResourceModel gerado são montadas. Determine se toBuilder deve ser habilitado por padrão ou exposto como uma flag de schema e, em seguida, verifique se os modelos Java gerados oferecem suporte ao workflow de cópia com builder solicitado.

Dear team,

I wonder if you folks would have any concerns about enabling toBuilder attribute for Lombok @Builder by default or with an additional schema flag?

At the moment, ResourceModel template generates non-parametrized @Builder: https://github.com/aws-cloudformation/cloudformation-cli-java-plugin/blob/master/python/rpdk/java/templates/init/guided_aws/ResourceModel.java#L20

One of the reasons I would like to see this flag enabled is a significant simplification of overriding massive resource model definitions in testing, especially in testing an UpdateHandler.

Here is an example:

public class AbstractTestBase {
  protected static final ResourceModel MODEL_BEFORE;
  protected static final ResourceModel MODEL_AFTER;

  static {
    MODEL_BEFORE = ResourceModel.builder()
      .foo("foo-before")
      .bar("bar-before")
      .baz("baz-before")
      .build();
    MODEL_AFTER = ResourceModel.builder()
      .foo("foo-before")
      .bar("bar-before")
      .baz("totally-different-baz")
      .build();
  }
}

Assume I'm using these models in UpdateHandler test suite. If the update flow has a broad branching based on model attribute invariants, one has to initiate separate model instances for each branch case. It's completely fine for a 5-10 attribute models, but the burden of carrying things around grows once one has to deal with a 30-50 attribute model.

Having toBuilder = true enabled in ResourceModel definition would let one define models like

public class AbstractTestBase {
  protected static final ResourceModel MODEL_BEFORE;
  protected static final ResourceModel MODEL_AFTER;

  static {
    MODEL_BEFORE = ResourceModel.builder()
      .foo("foo-before")
      .bar("bar-before")
      .baz("baz-before")
      .build();
    MODEL_AFTER = MODEL_BEFORE.toBuilder()
      .baz("totally-different-baz")
      .build();
  }
}

In fact, being able to override a static model locally within the current test case scope is even better, it could look like:

public class UpdateHandlerTest extends AbstractTestBase {
  //...
  public void handleRequest_SimpleSuccess() {
    final ResourceModel modelWithUpdatedBaz = MODEL_BEFORE.toBuilder()
      .baz("totally-different-baz")
      .build();
      //...
  }
}