AWSTemplateFormatVersion: 2010-09-09
Description: >-
  AWS CloudFormation Template to create network. It's believed that network
  typically exists for most of the customers using AWS and the same could be
  reused. This template is for reference purpose for customers who want to
  create VPC & subnets.
Metadata:
  AWS::CloudFormation::Interface:
    ParameterGroups:
      - Label:
          default: "Availability Zones configuration"
        Parameters:
          - AZs
          - NumAZs
      - Label:
          default: "VPC configuration"
        Parameters:
          - VPCCidr
          - VPCTenancy
      - Label:
          default: "Public Subnet configuration"
        Parameters:
          - PublicSubnet1Cidr
          - PublicSubnet2Cidr
          - PublicSubnet3Cidr
          - PublicSubnet4Cidr
      - Label:
          default: "Private subnet configuration"
        Parameters:
          - CreatePrivateSubnets
          - PrivateSubnet1Cidr
          - PrivateSubnet2Cidr
          - PrivateSubnet3Cidr
          - PrivateSubnet4Cidr
    ParameterLabels:
      AZs:
        default: "Availability Zones"
      NumAZs:
        default: "Number of Availability Zones"
      VPCCidr:
        default: "Enter IP address range for VPC"
      VPCTenancy:
        default: "VPC Tenancy"
      PublicSubnet1Cidr:
        default: "Public subnet #1 IP address range"
      PublicSubnet2Cidr:
        default: "Public subnet #2 IP address range"
      PublicSubnet3Cidr:
        default: "Public subnet #3 IP address range"
      PublicSubnet4Cidr:
        default: "Public subnet #4 IP address range"
      CreatePrivateSubnets:
        default: "Should private subnets be created in this VPC?"
      PrivateSubnet1Cidr:
        default: "Private subnet #1 IP address range"
      PrivateSubnet2Cidr:
        default: "Private subnet #2 IP address range"
      PrivateSubnet3Cidr:
        default: "Private subnet #3 IP address range"
      PrivateSubnet4Cidr:
        default: "Private subnet #4 IP address range"
Parameters:
  AZs:
    Description: >-
      List of AZs to use for the subnets in the VPC.
      Note: The logical order is preserved.
    Type: List<AWS::EC2::AvailabilityZone::Name>
  NumAZs:
    AllowedValues: [2, 3, 4]
    Description: >-
      Number of AZs to use in the VPC. This must match your
      selections in the list of AZs parameter.
    Default: 2
    Type: Number
  VPCCidr:
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
    ConstraintDescription: must be a valid IP CIDR range of the form x.x.x.x/x.
    Default: 10.0.0.0/16
    Description: The IP address range for this VPC
    MaxLength: '18'
    MinLength: '9'
    Type: String
  VPCTenancy:
    AllowedValues: [default, dedicated]
    Default: default
    Description: The allowed tenancy of instances launched into the VPC
    Type: String
  PublicSubnet1Cidr:
    Description: >-
      The IP address range for 'public' subnet in AZ 1
    Type: String
    MinLength: '9'
    MaxLength: '18'
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
    ConstraintDescription: must be a valid IP CIDR range of the form x.x.x.x/x.
    Default: 10.0.128.0/20
  PublicSubnet2Cidr:
    Description: >-
      The IP address range for 'public' subnet in AZ 2
    Type: String
    MinLength: '9'
    MaxLength: '18'
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
    ConstraintDescription: must be a valid IP CIDR range of the form x.x.x.x/x.
    Default: 10.0.144.0/20
  PublicSubnet3Cidr:
    Description: >-
      The IP address range for 'public' subnet in AZ 3
    Type: String
    MinLength: '9'
    MaxLength: '18'
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
    ConstraintDescription: must be a valid IP CIDR range of the form x.x.x.x/x.
    Default: 10.0.160.0/20
  PublicSubnet4Cidr:
    Description: >-
      The IP address range for 'public' subnet in AZ 4
    Type: String
    MinLength: '9'
    MaxLength: '18'
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
    ConstraintDescription: must be a valid IP CIDR range of the form x.x.x.x/x.
    Default: 10.0.176.0/20
  CreatePrivateSubnets:
    Description: >-
      Create private subnets in the VPC?
    Type: String
    Default: true
    AllowedValues: [true, false]
  PrivateSubnet1Cidr:
    Description: >-
      The IP address range for 'private' subnet in AZ 1
    Type: String
    MinLength: '9'
    MaxLength: '18'
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
    ConstraintDescription: must be a valid IP CIDR range of the form x.x.x.x/x.
    Default: 10.0.0.0/19
  PrivateSubnet2Cidr:
    Description: >-
      The IP address range for 'private' subnet in AZ 2
    Type: String
    MinLength: '9'
    MaxLength: '18'
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
    ConstraintDescription: must be a valid IP CIDR range of the form x.x.x.x/x.
    Default: 10.0.32.0/19
  PrivateSubnet3Cidr:
    Description: >-
      The IP address range for 'private' subnet in AZ 3
    Type: String
    MinLength: '9'
    MaxLength: '18'
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
    ConstraintDescription: must be a valid IP CIDR range of the form x.x.x.x/x.
    Default: 10.0.64.0/19
  PrivateSubnet4Cidr:
    Description: >-
      The IP address range for 'private' subnet in AZ 4
    Type: String
    MinLength: '9'
    MaxLength: '18'
    AllowedPattern: '(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/(\d{1,2})'
    ConstraintDescription: must be a valid IP CIDR range of the form x.x.x.x/x.
    Default: 10.0.96.0/19
Conditions:
  Cond3AZ: !Or [!Equals [!Ref NumAZs, 3], !Condition Cond4AZ]
  Cond4AZ: !Equals [!Ref NumAZs, 4]
  CondPrivateSubnet: !Equals [!Ref CreatePrivateSubnets, true]
  CondPrivateSubnet&3AZ: !And [!Equals [!Ref CreatePrivateSubnets, true], !Condition Cond3AZ]
  CondPrivateSubnet&4AZ: !And [!Equals [!Ref CreatePrivateSubnets, true], !Condition Cond4AZ]
  CondNATGateway: !Condition CondPrivateSubnet
  CondNATGateway&3AZ: !And [!Condition CondPrivateSubnet, !Condition Cond3AZ]
  CondNATGateway&4AZ: !And [!Condition CondPrivateSubnet, !Condition Cond4AZ]
  CondNVirginiaRegion: !Equals [!Ref 'AWS::Region', 'us-east-1']
Resources:
  DHCPOptions:
    Type: 'AWS::EC2::DHCPOptions'
    Properties:
      DomainName: !If
        - CondNVirginiaRegion
        - ec2.internal
        - !Join 
          - ''
          - - !Ref 'AWS::Region'
            - .compute.internal
      DomainNameServers:
        - AmazonProvidedDNS
  VPC:
    Type: 'AWS::EC2::VPC'
    Properties:
      CidrBlock: !Ref VPCCidr
      EnableDnsSupport: true
      EnableDnsHostnames: true
      InstanceTenancy: !Ref VPCTenancy
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Sub 'vpc-${AWS::StackName}'
  VPCDHCPOptionsAssociation:
    Type: 'AWS::EC2::VPCDHCPOptionsAssociation'
    Properties:
      VpcId: !Ref VPC
      DhcpOptionsId: !Ref DHCPOptions
  InternetGateway:
    Type: 'AWS::EC2::InternetGateway'
    Properties:
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Ref 'AWS::StackName'
  AttachGateway:
    Type: 'AWS::EC2::VPCGatewayAttachment'
    Properties:
      VpcId: !Ref VPC
      InternetGatewayId: !Ref InternetGateway
  PrivateSubnet1:
    Condition: CondPrivateSubnet
    Type: 'AWS::EC2::Subnet'
    Properties:
      AvailabilityZone: !Select [0, !Ref AZs]
      CidrBlock: !Ref PrivateSubnet1Cidr
      MapPublicIpOnLaunch: false
      VpcId: !Ref VPC
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Sub 'Private subnet 1 (${AWS::StackName})'
  PrivateSubnet2:
    Condition: CondPrivateSubnet
    Type: 'AWS::EC2::Subnet'
    Properties:
      AvailabilityZone: !Select [1, !Ref AZs]
      CidrBlock: !Ref PrivateSubnet2Cidr
      MapPublicIpOnLaunch: false
      VpcId: !Ref VPC
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Sub 'Private subnet 2 (${AWS::StackName})'
  PrivateSubnet3:
    Condition: CondPrivateSubnet&3AZ
    Type: 'AWS::EC2::Subnet'
    Properties:
      AvailabilityZone: !Select [2, !Ref AZs]
      CidrBlock: !Ref PrivateSubnet3Cidr
      MapPublicIpOnLaunch: false
      VpcId: !Ref VPC
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Sub 'Private subnet 3 (${AWS::StackName})'
  PrivateSubnet4:
    Condition: CondPrivateSubnet&4AZ
    Type: 'AWS::EC2::Subnet'
    Properties:
      AvailabilityZone: !Select [3, !Ref AZs]
      CidrBlock: !Ref PrivateSubnet4Cidr
      MapPublicIpOnLaunch: false
      VpcId: !Ref VPC
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Sub 'Private subnet 4 (${AWS::StackName})'
  PublicSubnet1:
    Type: 'AWS::EC2::Subnet'
    Properties:
      AvailabilityZone: !Select [0, !Ref AZs]
      CidrBlock: !Ref PublicSubnet1Cidr
      MapPublicIpOnLaunch: true
      VpcId: !Ref VPC
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Sub 'Public subnet 1 (${AWS::StackName})'
  PublicSubnet2:
    Type: 'AWS::EC2::Subnet'
    Properties:
      AvailabilityZone: !Select [1, !Ref AZs]
      CidrBlock: !Ref PublicSubnet2Cidr
      MapPublicIpOnLaunch: true
      VpcId: !Ref VPC
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Sub 'Public subnet 2 (${AWS::StackName})'
  PublicSubnet3:
    Condition: Cond3AZ
    Type: 'AWS::EC2::Subnet'
    Properties:
      AvailabilityZone: !Select [2, !Ref AZs]
      CidrBlock: !Ref PublicSubnet3Cidr
      MapPublicIpOnLaunch: true
      VpcId: !Ref VPC
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Sub 'Public subnet 3 (${AWS::StackName})'
  PublicSubnet4:
    Condition: Cond4AZ
    Type: 'AWS::EC2::Subnet'
    Properties:
      AvailabilityZone: !Select [3, !Ref AZs]
      CidrBlock: !Ref PublicSubnet4Cidr
      MapPublicIpOnLaunch: true
      VpcId: !Ref VPC
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Sub 'Public subnet 4 (${AWS::StackName})'
  PublicSubnetRouteTable:
    Type: 'AWS::EC2::RouteTable'
    Properties:
      VpcId: !Ref VPC
      Tags:
        - Key: Application
          Value: !Ref 'AWS::StackId'
        - Key: Name
          Value: !Sub 'Public RT (${AWS::StackName})'
  PublicSubnetRoute:
    Type: 'AWS::EC2::Route'
    DependsOn: AttachGateway
    Properties:
      RouteTableId: !Ref PublicSubnetRouteTable
      DestinationCidrBlock: 0.0.0.0/0
      GatewayId: !Ref InternetGateway
  PublicSubnet1RouteTableAssociation:
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      SubnetId: !Ref PublicSubnet1
      RouteTableId: !Ref PublicSubnetRouteTable
  PublicSubnet2RouteTableAssociation:
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      SubnetId: !Ref PublicSubnet2
      RouteTableId: !Ref PublicSubnetRouteTable
  PublicSubnet3RouteTableAssociation:
    Condition: Cond3AZ
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      SubnetId: !Ref PublicSubnet3
      RouteTableId: !Ref PublicSubnetRouteTable
  PublicSubnet4RouteTableAssociation:
    Condition: Cond4AZ
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      SubnetId: !Ref PublicSubnet4
      RouteTableId: !Ref PublicSubnetRouteTable
  NAT1EIP:
    Condition: CondPrivateSubnet
    DependsOn: AttachGateway
    Type: 'AWS::EC2::EIP'
    Properties:
      Domain: vpc
  NAT2EIP:
    Condition: CondPrivateSubnet
    DependsOn: AttachGateway
    Type: 'AWS::EC2::EIP'
    Properties:
      Domain: vpc
  NAT3EIP:
    Condition: CondPrivateSubnet&3AZ
    DependsOn: AttachGateway
    Type: 'AWS::EC2::EIP'
    Properties:
      Domain: vpc
  NAT4EIP:
    Condition: CondPrivateSubnet&4AZ
    DependsOn: AttachGateway
    Type: 'AWS::EC2::EIP'
    Properties:
      Domain: vpc
  NATGateway1:
    Condition: CondNATGateway
    DependsOn: AttachGateway
    Type: 'AWS::EC2::NatGateway'
    Properties:
      AllocationId: !GetAtt NAT1EIP.AllocationId
      SubnetId: !Ref PublicSubnet1
  NATGateway2:
    Condition: CondNATGateway
    DependsOn: AttachGateway
    Type: 'AWS::EC2::NatGateway'
    Properties:
      AllocationId: !GetAtt NAT2EIP.AllocationId
      SubnetId: !Ref PublicSubnet2
  NATGateway3:
    Condition: CondNATGateway&3AZ
    DependsOn: AttachGateway
    Type: 'AWS::EC2::NatGateway'
    Properties:
      AllocationId: !GetAtt NAT3EIP.AllocationId
      SubnetId: !Ref PublicSubnet3
  NATGateway4:
    Condition: CondNATGateway&4AZ
    DependsOn: AttachGateway
    Type: 'AWS::EC2::NatGateway'
    Properties:
      AllocationId: !GetAtt NAT4EIP.AllocationId
      SubnetId: !Ref PublicSubnet4
  PrivateSubnet1RouteTable:
    Condition: CondPrivateSubnet
    Type: 'AWS::EC2::RouteTable'
    Properties:
      VpcId: !Ref VPC
      Tags:
        - Key: Name
          Value: !Sub 'Private RT 1 (${AWS::StackName})'
  PrivateSubnet1Route:
    Condition: CondPrivateSubnet
    Type: 'AWS::EC2::Route'
    Properties:
      RouteTableId: !Ref PrivateSubnet1RouteTable
      DestinationCidrBlock: 0.0.0.0/0
      NatGatewayId: !Ref NATGateway1
  PrivateSubnet1RouteTableAssociation:
    Condition: CondPrivateSubnet
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      SubnetId: !Ref PrivateSubnet1
      RouteTableId: !Ref PrivateSubnet1RouteTable
  PrivateSubnet2RouteTable:
    Condition: CondPrivateSubnet
    Type: 'AWS::EC2::RouteTable'
    Properties:
      VpcId: !Ref VPC
      Tags:
        - Key: Name
          Value: !Sub 'Private RT 2 (${AWS::StackName})'
  PrivateSubnet2Route:
    Condition: CondPrivateSubnet
    Type: 'AWS::EC2::Route'
    Properties:
      RouteTableId: !Ref PrivateSubnet2RouteTable
      DestinationCidrBlock: 0.0.0.0/0
      NatGatewayId: !Ref NATGateway2
  PrivateSubnet2RouteTableAssociation:
    Condition: CondPrivateSubnet
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      SubnetId: !Ref PrivateSubnet2
      RouteTableId: !Ref PrivateSubnet2RouteTable
  PrivateSubnet3RouteTable:
    Condition: CondPrivateSubnet&3AZ
    Type: 'AWS::EC2::RouteTable'
    Properties:
      VpcId: !Ref VPC
      Tags:
        - Key: Name
          Value: !Sub 'Private RT 3 (${AWS::StackName})'
  PrivateSubnet3Route:
    Condition: CondPrivateSubnet&3AZ
    Type: 'AWS::EC2::Route'
    Properties:
      RouteTableId: !Ref PrivateSubnet3RouteTable
      DestinationCidrBlock: 0.0.0.0/0
      NatGatewayId: !Ref NATGateway3
  PrivateSubnet3RouteTableAssociation:
    Condition: CondPrivateSubnet&3AZ
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      SubnetId: !Ref PrivateSubnet3
      RouteTableId: !Ref PrivateSubnet3RouteTable
  PrivateSubnet4RouteTable:
    Condition: CondPrivateSubnet&4AZ
    Type: 'AWS::EC2::RouteTable'
    Properties:
      VpcId: !Ref VPC
      Tags:
        - Key: Name
          Value: !Sub 'Private RT 4 (${AWS::StackName})'
  PrivateSubnet4Route:
    Condition: CondPrivateSubnet&4AZ
    Type: 'AWS::EC2::Route'
    Properties:
      RouteTableId: !Ref PrivateSubnet4RouteTable
      DestinationCidrBlock: 0.0.0.0/0
      NatGatewayId: !Ref NATGateway4
  PrivateSubnet4RouteTableAssociation:
    Condition: CondPrivateSubnet&4AZ
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      SubnetId: !Ref PrivateSubnet4
      RouteTableId: !Ref PrivateSubnet4RouteTable
Outputs:
  VPC:
    Description: Newly created VPC
    Value: !Ref VPC
    Export:
      Name: !Sub '${AWS::StackName}-VPC'
  PublicSubnet1:
    Description: Public Subnet 1
    Value: !Ref PublicSubnet1
    Export:
      Name: !Sub '${AWS::StackName}-PublicSubnet1'
  PublicSubnet2:
    Description: Public Subnet 2
    Value: !Ref PublicSubnet2
    Export:
      Name: !Sub '${AWS::StackName}-PublicSubnet2'
  PublicSubnet3:
    Condition: Cond3AZ
    Description: Public Subnet 3
    Value: !Ref PublicSubnet3
    Export:
      Name: !Sub '${AWS::StackName}-PublicSubnet3'
  PublicSubnet4:
    Condition: Cond4AZ
    Description: Public Subnet 4
    Value: !Ref PublicSubnet4
    Export:
      Name: !Sub '${AWS::StackName}-PublicSubnet4'
  PrivateSubnet1:
    Condition: CondPrivateSubnet
    Description: Private Subnet 1
    Value: !Ref PrivateSubnet1
    Export:
      Name: !Sub '${AWS::StackName}-PrivateSubnet1'
  PrivateSubnet2:
    Condition: CondPrivateSubnet
    Description: Private Subnet 2
    Value: !Ref PrivateSubnet2
    Export:
      Name: !Sub '${AWS::StackName}-PrivateSubnet2'
  PrivateSubnet3:
    Condition: CondPrivateSubnet&3AZ
    Description: Private Subnet 3
    Value: !Ref PrivateSubnet3
    Export:
      Name: !Sub '${AWS::StackName}-PrivateSubnet3'
  PrivateSubnet4:
    Condition: CondPrivateSubnet&4AZ
    Description: Private Subnet 4
    Value: !Ref PrivateSubnet4
    Export:
      Name: !Sub '${AWS::StackName}-PrivateSubnet4'
  NAT1EIP:
    Condition: CondPrivateSubnet
    Description: NAT 1 IP address
    Value: !Ref NAT1EIP
    Export:
      Name: !Sub '${AWS::StackName}-NAT1EIP'
  NAT2EIP:
    Condition: CondPrivateSubnet
    Description: NAT 2 IP address
    Value: !Ref NAT2EIP
    Export:
      Name: !Sub '${AWS::StackName}-NAT2EIP'
  NAT3EIP:
    Condition: CondPrivateSubnet&3AZ
    Description: NAT 3 IP address
    Value: !Ref NAT3EIP
    Export:
      Name: !Sub '${AWS::StackName}-NAT3EIP'
  NAT4EIP:
    Condition: CondPrivateSubnet&4AZ
    Description: NAT 4 IP address
    Value: !Ref NAT4EIP
    Export:
      Name: !Sub '${AWS::StackName}-NAT4EIP'