tgw-routes.njk

AWSTemplateFormatVersion: "2010-09-09"
Description: >-
  Setup Transit Gateway routes to spoke VPCs
Parameters:
  VpcSubnetIDs:
    Description: VPC subnets to associate with Transit Gateway
    Type: List<AWS::EC2::Subnet::Id>
  VpcId:
    Description: The VPC ID
    Type: AWS::EC2::VPC::Id
  VpcRouteTableId:
    Description: The VPC route table ID
    Type: String
  TransitGatewayId:
    Description: The Transit Gateway ID
    Type: String
Resources:
  TransitGatewayAttachment:
    Type: AWS::EC2::TransitGatewayAttachment
    Properties:
      SubnetIds: !Ref VpcSubnetIDs
      Tags:
        - Key: Application
          Value: NetworkServiceTransitGateway
      TransitGatewayId: !Ref TransitGatewayId
      VpcId: !Ref VpcId
{% for spoke, spoke_data in TgwSpokes %}
  TgwSpokeRoute{{ spoke | replace('-','') }}:
    Type: 'AWS::EC2::Route'
    DependsOn: TransitGatewayAttachment
    Properties:
      RouteTableId: !Ref VpcRouteTableId
      TransitGatewayId: !Ref TransitGatewayId
      DestinationCidrBlock: {{ spoke_data.CIDR }}
{% endfor %}

Outputs:
  TransitGatewayAttachmentId:
    Description: "Transit Gateway Attachment ID"
    Value: !Ref TransitGatewayAttachment
    Export:
      Name: !Sub '${AWS::StackName}-TransitGatewayAttachmentId'