aws-ec2: support subnet group names on fromVpcAttributes

[jaecktec]

Describe the feature

When importing a VPC I'd like to support names for subnets.

Use Case

When multiple subnet groups for one network type (for example ISOLATED) exist I want to select a certain group using subnet selection.

Proposed Solution

extend fromVpcAttributes -> VpcAttributes so an import can look like this:

Vpc.fromVpcAttributes(this, 'Vpc', {
  vpcId: 'vpc-id',
  isolatedSubnetNames: [
    { subnetGroupName: 'Database', subnetId: 'subnet-database-1' },
    { subnetGroupName: 'Database', subnetId: 'subnet-database-2' },
    { subnetGroupName: 'App', subnetId: 'subnet-app-1' },
    { subnetGroupName: 'App', subnetId: 'subnet-app-2' },
  ],
});

Other Information

Right now it's only possible to import up to 3 different subnet groups, however there are instances where I want to have more subnet groups.

Acknowledgements

• I may be able to implement this feature request
• This feature might incur a breaking change

CDK version used

2.163.1

Environment details (OS name and version, etc.)

[khushail]

Thans @jaecktec for reaching out and requesting this. I see fromVPCAttributes is inherently implementing VPCAttributes so this should be feasible to do -

aws-cdk/packages/aws-cdk-lib/aws-ec2/lib/vpc.ts

Line 705 in 75cf2e0

export interface VpcAttributes {

However I see subnetGroupName is provided in this interface.You can use subnetSelection method and import by subnet group name.

Marking this as P2 as its good to have and won't be immediately addressed by the team but would be on their radar. Contributions from community are also welcome.

[jaecktec]

Hey, yeah so how I get it is that you can import a single subnet group name - however I really don't see much value in that.

I would however like to import multiple different subnet group names.
So far I can only import three groups of subnets and give each a distinct name, however it is not possible to import lets say two subnet groups of type 'internal' with distinct names.

[khushail]

@jaecktec , thanks for replying back with clarification around your usecase.