create-vpc.yaml

AWSTemplateFormatVersion: '2010-09-09'
Description: 'Simple (not production-ready) VPC'

Parameters:
  ClassB:
    Description: 'Class B of VPC (10.XXX.0.0/16)'
    Type: Number
    Default: 0
    ConstraintDescription: 'Must be in the range [0-255]'
    MinValue: 0
    MaxValue: 255
  Owner:
    Description: 'Owner of the resources.'
    Type: String
  
Resources:
  VPC:
    Type: 'AWS::EC2::VPC'
    Properties:
      CidrBlock: !Sub '10.${ClassB}.0.0/16'
      EnableDnsSupport: true
      EnableDnsHostnames: true
      InstanceTenancy: default
      Tags:
      - Key: Name
        Value: !Sub '${Owner}-vpc-${ClassB}'
      - Key: Owner
        Value: !Sub '${Owner}'

  InternetGateway:
    Type: 'AWS::EC2::InternetGateway'
    Properties:
      Tags:
      - Key: Name
        Value: !Sub '${Owner}-igw-${ClassB}'
      - Key: Owner
        Value: !Sub '${Owner}'

  VPCGatewayAttachment:
    Type: 'AWS::EC2::VPCGatewayAttachment'
    Properties:
      VpcId: !Ref VPC
      InternetGatewayId: !Ref InternetGateway

  WebSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Allow http to client host
      VpcId: !Ref VPC
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: 80
          ToPort: 80
          CidrIp: 0.0.0.0/0

  SubnetAPublic:
    Type: 'AWS::EC2::Subnet'
    Properties:
      AvailabilityZone: !Select [0, !GetAZs '']
      CidrBlock: !Sub '10.${ClassB}.0.0/20'
      MapPublicIpOnLaunch: true
      VpcId: !Ref VPC
      Tags:
      - Key: Name
        Value: !Sub '${Owner}-sub-${ClassB}-A public'

  SubnetAPrivate:
    Type: 'AWS::EC2::Subnet'
    Properties:
      AvailabilityZone: !Select [0, !GetAZs '']
      CidrBlock: !Sub '10.${ClassB}.16.0/20'
      VpcId: !Ref VPC
      Tags:
      - Key: Name
        Value: !Sub '${Owner}-sub-${ClassB}-A private'

  RouteTablePublic:
    Type: 'AWS::EC2::RouteTable'
    Properties:
      VpcId: !Ref VPC
      Tags:
      - Key: Name
        Value: !Sub '${Owner}-rt-${ClassB}-public'
      - Key: Owner
        Value: !Sub '${Owner}'

  RouteTableAssociationAPublic:
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      SubnetId: !Ref SubnetAPublic
      RouteTableId: !Ref RouteTablePublic

  RouteTablePublicInternetRoute: 
    Type: 'AWS::EC2::Route'
    DependsOn: VPCGatewayAttachment
    Properties:
      RouteTableId: !Ref RouteTablePublic
      DestinationCidrBlock: '0.0.0.0/0'
      GatewayId: !Ref InternetGateway      

Outputs:
  VPC:
    Description: 'VPC.'
    Value: !Ref VPC
    Export:
      Name: !Sub '${AWS::StackName}-VPC'