/**
     * Nested argument for the VPC associated with your cluster. Amazon EKS VPC resources have specific requirements to work properly with Kubernetes. For more information, see [Cluster VPC Considerations](<https://docs.aws.amazon.com/eks/latest/userguide/network_reqs.html>) and [Cluster Security Group Considerations](<https://docs.aws.amazon.com/eks/latest/userguide/sec-group-reqs.html>) in the Amazon EKS User Guide. Configuration detailed below.
     */
    public readonly vpcConfig: pulumi.Output<{ securityGroupIds?: string[], subnetIds: string[], vpcId: string }>;

Vpc.fromExistingIds(..., { vpcId: eksCluster.vpcConfig.vpcId })

eks.Cluster

vpcId

new eks.Cluster()

Shouldn't that be an option to

cluster.createNodeGroup()

, though?

numOfAvailAbilityZones

@pulumi/eks

export function getSubnetIdInAZ(cluster: eks.Cluster, az: string) {
  const subnetIds = cluster.eksCluster.vpcConfig.subnetIds;
  const index = subnetIds.apply(ids =>
    Promise.all(
      ids.map(id =>
        aws.ec2.getSubnet({ id }).then(subnet => subnet.availabilityZone)
      )
    ).then(azs => azs.indexOf(az))
  );
  return index.apply(index => subnetIds[index]);
}

ClusterNodeGroupOptions

export function getSubnetIdInAZ(cluster: eks.Cluster, az: string) {
  const { subnetIds } = cluster.eksCluster.vpcConfig;
  return subnetIds.apply(async ids => {
    const subnets = await Promise.all(ids.map(id => aws.ec2.getSubnet({ id })));
    const subnet = subnets.find(subnet => subnet.availabilityZone === az);
    if (!subnet) {
      throw new Error(`No subnet found in ${az} zone`);
    }
    return subnet.id;
  });
}