fix(riff-raff.yaml): Loosen restrictions on GuStacks in an App

[akash1810]

Background

When we added riff-raff.yaml generation in #1372, we had a validation step that:

1. Discovered all the GuStacks in an App
2. Discovered the set of regions
3. Discovered the set of stackss
4. Discovered the set of stages
5. For each combination of the above, expected to find a GuStack that matched.

This meant, for example, for the following:

class MyDatabaseStack extends GuStack {}
class MyAppStack extends GuStack {}

new MyDatabaseStack({ env: { region: 'eu-west-1' }, stack: 'frontend', stage: 'CODE' });
new MyAppStack({ env: { region: 'eu-west-1' }, stack: 'frontend', stage: 'CODE' });
new MyAppStack({ env: { region: 'eu-west-1' }, stack: 'frontend', stage: 'PROD' });

We'd get validation errors as there is no PROD MyDatabaseStack definition.

The aim of this validation is to only produce riff-raff.yaml that works.

With MyDatabaseStack of PROD missing, when we deploy PROD, Riff-Raff would fail to locate the CloudFormation template file, as it simply doesn't exist, and the deployment would fail.

This behaviour is due to allowedStages (correctly) being a property at the root of the riff-raff.yaml file, rather than a property per deployment.

However, there are some niche scenarios where this 4 part validation is too strict.

What does this change?

In this change, we support the, rather niche, use-case of deploying different GuStacks to multiple AWS accounts (aka Riff-Raff stacks), and regions. For example:

class PrimaryWaf extends GuStack {}
class TeamcityWaf extends GuStack {}

new TeamcityWaf({ env: { region: 'eu-west-1' }, stack: 'deploy', stage: 'INFRA' });
new PrimaryWaf({ env: { region: 'eu-west-1' }, stack: 'deploy', stage: 'INFRA' });
new PrimaryWaf({ env: { region: 'eu-west-1' }, stack: 'security', stage: 'INFRA' });
new PrimaryWaf({ env: { region: 'us-east-1' }, stack: 'security', stage: 'INFRA' });

To get this to work, the validation step changes (see changes to isCdkStackPresent).

Previously the requirement was that every combination of GuStack, stack, stage, and region was present in an App, however this is unnecessarily restrictive for the above use-case.

In this change, the validation becomes every combination of stack, and stage are present in an App.

How to test

See the added tests, also https://github.com/guardian/waf/pull/21.

How can we measure success?

We can auto-generate the riff-raff.yaml file for more services, such as https://github.com/guardian/waf.

Have we considered potential risks?

N/A - the current tests continue to pass, so existing uses of this feature will continue to work.

Checklist

• [ ] I have listed any breaking changes, along with a migration path ¹
• I have updated the documentation as required for the described changes ²

Footnotes

1. Consider whether this is something that will mean changes to projects that have already been migrated, or to the CDK CLI tool. If changes are required, consider adding a checklist here and/or linking to related PRs. ↩

2. If you are adding a new construct or pattern, has new documentation been added? If you are amending defaults or changing behaviour, are the existing docs still valid? ↩

[akash1810]

Previously this was missing 4 definitions:

PASS src/experimental/riff-raff-yaml-file/index.test.ts
  ● Console

    console.log
      Unable to produce a working riff-raff.yaml file; missing 4 definitions (details below)

      at RiffRaffYamlFileExperimental.validateStacksInApp (src/experimental/riff-raff-yaml-file/index.ts:195:15)

    console.log
      For the class: MyApplicationStack

      at src/experimental/riff-raff-yaml-file/index.ts:197:17
          at Array.forEach (<anonymous>)

    console.log
      ┌───────────────┬────────────────────────────┐
      │    (index)    │         eu-west-1          │
      ├───────────────┼────────────────────────────┤
      │    deploy     │ { CODE: '✅', PROD: '✅' } │
      │ media-service │ { CODE: '❌', PROD: '✅' } │
      └───────────────┴────────────────────────────┘

      at src/experimental/riff-raff-yaml-file/index.ts:198:17
          at Array.forEach (<anonymous>)

    console.log
      For the class: MyDatabaseStack

      at src/experimental/riff-raff-yaml-file/index.ts:197:17
          at Array.forEach (<anonymous>)

    console.log
      ┌───────────────┬────────────────────────────┐
      │    (index)    │         eu-west-1          │
      ├───────────────┼────────────────────────────┤
      │    deploy     │ { CODE: '❌', PROD: '✅' } │
      │ media-service │ { CODE: '❌', PROD: '❌' } │
      └───────────────┴────────────────────────────┘

      at src/experimental/riff-raff-yaml-file/index.ts:198:17

The changes in this PR means only 1 definition is missing:

PASS src/experimental/riff-raff-yaml-file/index.test.ts
  ● Console

    console.log
      Unable to produce a working riff-raff.yaml file; missing 1 definitions (details below)

      at RiffRaffYamlFileExperimental.validateStacksInApp (src/experimental/riff-raff-yaml-file/index.ts:165:15)

    console.log
      ┌───────────────┬──────┬──────┐
      │    (index)    │ CODE │ PROD │
      ├───────────────┼──────┼──────┤
      │    deploy     │ '✅' │ '✅' │
      │ media-service │ '❌' │ '✅' │
      └───────────────┴──────┴──────┘

      at RiffRaffYamlFileExperimental.validateStacksInApp (src/experimental/riff-raff-yaml-file/index.ts:166:15)

[kenoir]

I think it would be useful to validate and describe the logic in this function as a unit test apart from the higher level behaviour, not blocking for merge.

[akash1810]

Agreed!

[github-actions]

🎉 This PR is included in version 49.0.3 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

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