Rules:
  KeyPairsNotEmpty:
    Assertions:
    - Assert:
        Fn::Not:
        - Fn::EachMemberEquals:
          - Fn::RefAll: AWS::EC2::KeyPair::KeyName
          - ''
      AssertDescription: All key pair parameters must not be empty
  SubnetsInVPC:
    Assertions:
    - Assert:
        Fn::EachMemberIn:
        - Fn::ValueOfAll:
          - AWS::EC2::Subnet::Id
          - VpcId
        - Fn::RefAll: AWS::EC2::VPC::Id
      AssertDescription: All subnets must in the VPC