feat(core): overrideLogicalId: override IDs of CFN elements

[eladb]

Allow users to explicitly override the logical ID of a CloudFormation
element (such as "Cfn" resources) by invoking overrideLogicalId
on the resource object.

For example:

const bucket = new s3.CfnBucket(this, 'MyBucket');
bucket.overrideLogicalId('YourBucket');

The resulting template will use YourBucket as the logical ID.

NOTE: the logicalId property will now return a stringified token
instead of a concrete value.

Fixes #1594

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Pull Request Checklist

• Testing
  • Unit test added
  • 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.

[eladb]

@Doug-AWS we should update the escape hatch topic to reflect this (instead of renames)

[sam-goodwin]

The behavior of sortedSet(this.dependsOn) will be different now that it is a Set<Resource>.

[eladb]

It will actually be fine, because it will be sorted by the token, which is good enough for our purposes, no?

[rix0rrr]

The goal is to get dependencies into a stable order for purposes of comparisons.

[eladb]

So the tokens are okay for that purpose

[rix0rrr]

No, you're doing sort(Resource) THEN map to ID.

So the sort order is not based on the token strings, but on opaque objects. No idea how JavaScript will sort those.

If anything, you should have done sort(resource.map(r => r.id))

[eladb]

got it, you are right

[mergify]

Thanks so much for taking the time to contribute to the AWS CDK ❤️

We will shortly assign someone to review this pull request and help get it
merged. In the meantime, please take a minute to make sure you follow this
checklist:

• PR title type(scope): text
  • type: fix, feat, refactor go into CHANGELOG, chore is hidden
  • scope: name of module without aws- or cdk- prefix or postfix (e.g. s3 instead of aws-s3-deployment)
  • text: use all lower-case, do not end with a period, do not include issue refs
• PR Description
  • Rationale: describe rationale of change and approach taken
  • Issues: indicate issues fixed via: fixes #xxx or closes #xxx
  • Breaking?: last paragraph: BREAKING CHANGE: <describe what changed + link for details>
• Testing
  • Unit test added. Prefer to add a new test rather than modify existing tests
  • CLI or init templates change? Re-run/add CLI integration tests
• Documentation
  • README: update module README to describe new features
  • API docs: public APIs must be documented. Copy from official AWS docs when possible
  • Design: for significant features, follow design process