How to create security group in aws cdk in python?

Question

Hi I am trying to write seurity group using aws cdk. I know how to write it in using cloud formation. Below is my cloud formation template.

MerchWebServicesSecurityGroup:
    Type: "AWS::EC2::SecurityGroup"
    Properties:
      Tags:
        - Key: "Name"
          Value: !Ref "AWS::StackName"
      GroupDescription: "EC2 Services Security Group"
      VpcId:
        Fn::ImportValue: "infra-vpc-base::VpcId"
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: "80"
          ToPort: "80"
          SourceSecurityGroupId: !Ref MerchWebServicesLoadBalancerSecurityGroup
        - IpProtocol: tcp
          FromPort: "443"
          ToPort: "443"
          SourceSecurityGroupId: !Ref MerchWebServicesLoadBalancerSecurityGroup
        - IpProtocol: tcp
          FromPort: 31000
          ToPort: 65535
          SourceSecurityGroupId: !Ref MerchWebServicesLoadBalancerSecurityGroup

I tried to write security group as below in python cdk.

  mws_vpc_sg  = ec2.SecurityGroup(stack, "MerchWebServicesSecurityGroup",
        description= "Allow ssh access to ec2 instances",
        security_group_name= "MerchWebServicesSecurityGroup",
        vpc= vpc
    );

 mws_vpc_sg.add_ingress_rule(?, Port.tcp(80));

Above I want to add sourceSecurityGroupId and port. Can someone help me to write this? Any help would be appreciated. Thanks

Answer 1

If you have created the other security group in CDK as well, you can just pass the security group as peer.

mws_vpc_sg.add_ingress_rule(load_balancer_sg, Port.tcp(80));

If you have created the security group somewhere else you need to obtain a ISecurityGroup from it using the static method:

var load_balancer_sg = ec2.SecurityGroup.fromSecurityGroupId(this, 'loadbalancer_sg', THE_ID_OF_THE_SG)