Create variable for VPC Endpoint creation if already created

[skpune]

Hi Team,

We are encountering an issue while deploying the start-stop solution in an account that has multiple MWAA environments. When we try to deploy the start-stop solution for another environment, the CloudFormation stack creation is failing and going into a rollback state.

The error message we are receiving is:

"Resource handler returned message: "private-dns-enabled cannot be set because there is already a conflicting DNS domain for states.us-east-1.amazonaws.com in the VPC vpc-0d301afa40a5768ca (Service: Ec2, Status Code: 400, Request ID: ccc14144-39f2-4078-b7e4-8f8dfc0b6d26)" (RequestToken: 3dc89c65-c60e-9c5c-6bf8-b261ab1a9fb7, HandlerErrorCode: GeneralServiceException)"

Could you please help us create a variable for the VPC endpoint creation, in case it already exists? This would allow us to handle the conflict and successfully deploy the start-stop solution for the additional MWAA environment.

Please let me know if you need any further information or assistance from our end.

Thanks, Shubham

[crupakheti]

Thank you, @skpune for your feature request! We plan to merge this feature in subsequent PRs.

[crupakheti]

Hey @skpune, while you are waiting on the enhancement, you can modify mwaa-main-stack.ts as follows: https://github.com/aws-samples/amazon-mwaa-examples/blob/80d36fce0bc6e8b34ce385f75a0b9e3b5abd284e/usecases/start-stop-mwaa-environment/lib/infrastructure/mwaa-main-stack.ts#L80C1-L102C1

...
  lookupVpc(props: MwaaMainStackProps): MwaaVpc {
    if (props.vpcId) {
      const vpc = ec2.Vpc.fromLookup(this, `${props.mainStackName}-external-vpc`, {
        vpcId: props.vpcId,
      });

      const subnets = props.subnetIds.map((id) => ec2.Subnet.fromSubnetId(this, id, id));
      const vpcSubnets = { subnets };

      const securityGroups = props.securityGroups.map((sg) => ec2.SecurityGroup.fromSecurityGroupId(this, sg, sg));

//      const vpce = vpc.addInterfaceEndpoint(`${props.mainStackName}-sf-vpce`, {
//        service: ec2.InterfaceVpcEndpointAwsService.STEP_FUNCTIONS,
//        subnets: vpcSubnets,
//        securityGroups: securityGroups,
//      });

//      return { vpc, vpcSubnets, securityGroups, vpce };
      return { vpc, vpcSubnets, securityGroups };
    }

    return {};
  }
...