VpcNetwork.importFromContext throws Cannot read property 'VpnGatewayId' of undefined

Versions

❯  cdk --version
0.25.2 (build 558d81f)

❯  cat package.json | grep aws-cdk     
    "aws-cdk": "^0.25.2"
    "@aws-cdk/aws-ec2": "^0.25.2",
    "@aws-cdk/aws-ecs": "^0.25.2",
    "@aws-cdk/cdk": "^0.25.2",

Problem Description

I have a very standard public/private VPC deployed (it was previously deployed with CDK).

I’m trying to import that VPC from a new CDK project, like so:

const vpc = ec2.VpcNetwork.importFromContext(this, 'VPC', {
    vpcName: 'Production/VPC'
})

When running cdk synth or cdk diff, an error is shown:

❯  cdk synth
Cannot read property 'VpnGatewayId' of undefined

I suspect this is related to #1899 that was merged 8 days ago. Related: #1523 (see comment by @brad-jones)

[PaulMaddox]

Problem lies here: packages/aws-cdk/lib/context-providers/vpcs.ts#L88

// Find attached+available VPN gateway for this VPC
const vpnGatewayResponse = await ec2.describeVpnGateways({
    Filters: [
    {
        Name: 'attachment.vpc-id',
        Values: [vpcId]
    },
    {
        Name: 'attachment.state',
        Values: ['attached']
    },
    {
        Name: 'state',
        Values: ['available']
    }
    ]
}).promise();
const vpnGatewayId = vpnGatewayResponse.VpnGateways ? vpnGatewayResponse.VpnGateways[0].VpnGatewayId : undefined;

If there are no VpnGateways, the DescribeVpnGateways SDK call will return an empty array like so:

❯  aws ec2 describe-vpn-gateways                                                                                                                  │
{                                                                                                                                                 │
    "VpnGateways": []                                                                                                                             │
}                                                                                                                                                 │

The ternary operator above should check array size, rather than whether it’s defined/null.

[rix0rrr]

We will do a release next week. If you don’t want to wait for that, you can check out the repository and do a local build. Be aware, you will need a Linux or mac otherwise the build is going to give you a lot of trouble.