How do I obtain the properties of an existing Transit Gateway with the CDK?-CodePudding

I am deploying my app into an account that has a Transit Gateway shared from another AWS account via Resource Access Manager.

I want to create a Transit Gateway VPC Attachment to that Transit Gateway.

To create the Transit Gateway VPC Attachment object I need to supply a Transit Gateway ID. https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-ec2.CfnTransitGatewayVpcAttachment.html#class-cfntransitgatewayvpcattachment-construct

I cannot find a way with the CDK to obtain the Transit Gateway ID from an existing Transit Gateway. What method would I use to obtain the Transit Gateway ID?

CodePudding user response：

I do not see the method to "lookup" the existing Transit Gateway in https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-ec2.CfnTransitGateway.html

I assume you could either

Export the Transit Gateway ID as a CloudFormation output in the stack where it is created?
Lookup the Transit Gateway ID yourself and inject it into CDK source code?

I ended up with 2nd option in one of the projects and did not face any issues later.

CodePudding user response：

use your SDK to look it up.

During the deploy of a stack, use your languages SDK (such as boto3 for python) to access the AWS API commands to look up the information and retrieve it. I do this regularly with Layers that are identical across multiple stacks, but you need the version number to import a layer (i don't want to create multiple versions of the same layer) - I use boto3 to get the most recent version of the layer and the from_attributes command to import it into the stack.

You can do something similar with whatever SDK implimentation for your chosen languages replicates this CLI command: https://docs.aws.amazon.com/cli/latest/reference/ec2/describe-transit-gateways.html