Consider providing CIDR in IVpc

Currently, there’s no easy way to get the CIDR of a VPC from IVpc interface although the Vpc implementation does via getCidr(). Please consider pulling up getCidr() to the interface.

NOTE: Structure out of date. Request still valid

[alex-berger]

Any progress on this? Actually I often end-up wanting to write something like this:

let sg: SecurityGroup = ...
let vpc = Vpc.fromLookup(this, '...', { tags: { "mytag": "my-value"}} )
for ( let subnet of vpc.privateSubnets ){
      sg.addIngressRule(subnet, new TcpPort(443), 'Allow inbound HTTPS traffic from private subnet')
}

However, not being able to obtain the CIDR(s) of imported IVpc respectively ISubnet makes this impossible. Vpc.fromLookup(this, '...', { tags: { "mytag": "my-value"}} ) implies that we have to lookup facts (attributes like VpcId, …) using AWS API anyway, so we could as well lookup the CIDR ranges.

[klang]

However I´ve noticed that the defaultChild property is not set when you for instance is looking up a subnet, but if you create the VPC and its subnets it works.

Which brings me back to my point: I may be missing how looking up information for existing infrastructure works.

It’s pretty easy to get yourself in a situation where the VPC and SubNets are given and non-negotiably out of your control (corp delivers those things with a VPN endpoint back to on-prem and don’t want anybody messing with it).

aws-cli has the entire set of describe-* functions and terraform has data resources for pretty much everything.

I’m sure that CDK must have something similar.