aws-ec2 update documentation to match environment-agnostic cloud assemblies feature #2922

[fortunecookiezen]

Note: for support questions, please first reference our documentation, then use Stackoverflow. This repository's issues are intended for feature requests and bug reports.

• I'm submitting a ...

  • 🪲 bug report
  • 🚀 feature request
  • 📚 construct library gap
  • ☎️ security issue or vulnerability => Please see policy
  • ❓ support request => Please see note at the top of this template.

• What is the current behavior?

construct Vpc ignores maxAZs when used without specifying aws region or account. It will always produce a vpc with subnets spread across 2 az if maxAZs >2 or unless maxAZs is <2 without producing an error or warning. API documentation for maxAZs indicates 3 is default.

If the current behavior is a 🪲bug🪲: Please provide the steps to reproduce

export class Vpc3Stack extends cdk.Stack {
constructor(scope: cdk.Construct, id: string, props?: cdk.StackProps) {
super(scope, id, props);

// The code that defines your stack goes here
const vpc = new ec2.Vpc(this, 'vpc', {
  cidr: '10.1.0.0/21',
  maxAZs: 3
});

npm run build && cdk synth

• What is the expected behavior (or behavior of feature suggested)?

Subnets/AZs should match maxAZs setting in SubnetConfiguration array or should issue a warning when unable to determine if maxAZs will be available in a given region. Documentation should be updated to indicate new behavior introduced in feature #2922

• What is the motivation / use case for changing the behavior or adding this feature?

Provide more transparent indication of why output is not as defined in stack or matching default value for maxAZs

• Please tell us about your environment:

  • CDK CLI Version: > 0.34.0
  • Module Version: xx.xx.xx
  • OS: all
  • Language: Typescript

• Other information (e.g. detailed explanation, stacktraces, related issues, suggestions how to fix, links for us to have context, eg. associated pull-request, stackoverflow, gitter, etc)

Another option would be to change maxAZs default to 2, and update documentation to indicate how to specifiy >2 availability zones by defining environment variables. A compelling argument could be made that Construct defaults should be region independent, and thus should not include default values that are not implementable in all AWS regions.

[rix0rrr]

Will be addressed by #3810

[SomayaB]

Closing since it should be addressed by the now merged #3810. Feel free to reopen if that's not the case.