fix: rename core classes adding a Cfn prefix

[skinny85]

To better align with our L1 layer that is closely tied to CloudFormation, add the Cfn prefix to classes from the @aws-cdk/cdk package.

BREAKING CHANGE: rename Output to CfnOutput.
BREAKING CHANGE: rename Condition to CfnCondition.
BREAKING CHANGE: rename StackElement to CfnElement.
BREAKING CHANGE: rename Parameter to CfnParameter.
BREAKING CHANGE: rename Resource to CfnResource.

Fixes #1462
Fixes #288

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Pull Request Checklist

• Testing
  • Unit test added (prefer not to modify an existing test, otherwise, it's probably a breaking change)
  • CLI change?: coordinate update of integration tests with team
  • cdk-init template change?: coordinated update of integration tests with team
• Docs
  • jsdocs: All public APIs documented
  • README: README and/or documentation topic updated
• Title and Description
  • Change type: title prefixed with fix, feat will appear in changelog
  • Title: use lower-case and doesn't end with a period
  • Breaking?: last paragraph: "BREAKING CHANGE: <describe what changed + link for details>"
  • Issues: Indicate issues fixed via: "Fixes #xxx" or "Closes #xxx"
• Sensitive Modules (requires 2 PR approvers)
  • IAM Policy Document (in @aws-cdk/aws-iam)
  • EC2 Security Groups and ACLs (in @aws-cdk/aws-ec2)
  • Grant APIs (only if not based on official documentation with a reference)

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license.

[skinny85]

There's also a bunch of other classes that were not mentioned in the #1462 issue, but perhaps should be renamed as well?

• Referenceable -> CfnReferenceable ?
• Include -> CfnInclude ?
• Rule -> CfnRule ?
• Mapping -> CfnMapping ?
• IConditionExpression -> ICfnConditionExpression ?

Let me know should those be included as well.

[RomainMuller]

We don't really have L2 surface for most of these things... Are we positive users don't routinely have to interact with those classes?

CfnCondition, CfnElement and CfnResource should 100% be the names though - my concern really is around Output and Parameter there.

[skinny85]

Addressed the comments.

[eladb]

Looks good to me.

Yes, good call about other renames:

• Rule to CfnRule
• Mapping to CfnMapping.
• Referenceable maybe to CfnRefElement (it's a CfnElement that can be Refed).
• IConditionExpression => ICfnConditionExpression

I wouldn't touch Include for now, if at all, it should be IncludeTemplate or IncludeCfnTemplate.

The "rule of thumb" is that we use the Cfn prefix only with types that represent CloudFormation template entities.

Also, CfnReference should be Reference (it's not only for CloudFormation refs anymore).

And please flatten the file tree while you are wrecking havoc in this library.

[eladb]

@RomainMuller wrote:

my concern really is around Output and Parameter there

I see your point about Output and Parameter, and I was wondering that myself. But then I convinced myself that in both cases, people will use them only if they care about CFN. A "CDK Native" user doesn't need to interact with these classes directly, right?

[skinny85]

Yes, good call about other renames:

• Rule to CfnRule

Done.

• Mapping to CfnMapping.

Done.

• Referenceable maybe to CfnRefElement (it's a CfnElement that can be Refed).

Done.

• IConditionExpression => ICfnConditionExpression

Done.

I wouldn't touch Include for now, if at all, it should be IncludeTemplate or IncludeCfnTemplate.

Left alone.

Also, CfnReference should be Reference (it's not only for CloudFormation refs anymore).

Done.

And please flatten the file tree while you are wrecking havoc in this library.

Done.

[skinny85]

Renamed Reference#isReference to isReferenceToken, as I missed that there's already an instance property with the name isReference (that's not legal in Java or C#).

[skinny85]

Rebased on top of Sam's changes to the AWS Glue package.

[fulghum]

Nice! Thanks for picking this one up @skinny85 !

[skinny85]

My pleasure :)