AWSTemplateFormatVersion: '2010-09-09'
Description: This template creates an Amazon VPC and subnet with the required configuration for a cross-realm trust.
Resources:
  VPC:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock: 10.0.0.0/16
      EnableDnsSupport: true
      EnableDnsHostnames: true
      InstanceTenancy: default
      Tags:
        - Key: Name
          Value: grpc-blog-vpc
  PublicSubnetA:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref 'VPC'
      CidrBlock: 10.0.1.0/24
      AvailabilityZone : !Join ['', [!Ref AWS::Region, a]]
      MapPublicIpOnLaunch: true
      Tags:
        - Key: Name
          Value: grpc-blog-vpc-subnet-a

  PublicSubnetB:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref 'VPC'
      CidrBlock: 10.0.2.0/24
      AvailabilityZone : !Join ['', [!Ref AWS::Region, b]]
      MapPublicIpOnLaunch: true
      Tags:
        - Key: Name
          Value: grpc-blog-vpc-subnet-b

  PublicSubnetC:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref 'VPC'
      CidrBlock: 10.0.3.0/24
      AvailabilityZone : !Join ['', [!Ref AWS::Region, c]]
      MapPublicIpOnLaunch: true
      Tags:
        - Key: Name
          Value: grpc-blog-vpc-subnet-c

  InternetGateway:
    Type: AWS::EC2::InternetGateway
    Properties:
      Tags:
        - Key: Name
          Value:  grpc-blog-vpc-igw
  MyGatewayAttachment:
    Type: AWS::EC2::VPCGatewayAttachment
    Properties:
      InternetGatewayId: !Ref 'InternetGateway'
      VpcId: !Ref 'VPC'
  PublicRouteTable:
    Type: AWS::EC2::RouteTable
    Properties:
      VpcId: !Ref 'VPC'
  PublicRoute:
    Type: AWS::EC2::Route
    Properties:
      RouteTableId: !Ref 'PublicRouteTable'
      DestinationCidrBlock: '0.0.0.0/0'
      GatewayId: !Ref 'InternetGateway'
    DependsOn:
      - MyGatewayAttachment
  PublicSubnetRouteAssociationA:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      RouteTableId: !Ref 'PublicRouteTable'
      SubnetId: !Ref 'PublicSubnetA'
  PublicSubnetRouteAssociationB:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      RouteTableId: !Ref 'PublicRouteTable'
      SubnetId: !Ref 'PublicSubnetB'
  PublicSubnetRouteAssociationC:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      RouteTableId: !Ref 'PublicRouteTable'
      SubnetId: !Ref 'PublicSubnetC'

  AdhocAccessSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: CloudFormationGroup
      VpcId: !Ref 'VPC'
      SecurityGroupIngress:
        - IpProtocol: '-1'
          CidrIp: 10.0.0.0/16
      Tags:
        - Key: Name
          Value: grpc-blog-vpc-master-securitygroup
  VPCDefaultSecurityGroupIngress:
    Type: AWS::EC2::SecurityGroupIngress
    Properties:
      GroupId: !GetAtt 'VPC.DefaultSecurityGroup'
      IpProtocol: '-1'
      CidrIp: 10.0.0.0/16
Outputs:
  StackName:
    Value: !Ref 'AWS::StackName'
  SubnetIDA:
    Description: Public Subnet A.
    Value: !Ref 'PublicSubnetA'
    Export:
      Name: "grpc-blog-public-subnet-a"
  SubnetIDB:
    Description: Public Subnet B.
    Value: !Ref 'PublicSubnetB'
    Export:
      Name: "grpc-blog-public-subnet-b"
  SubnetIDC:
    Description: Public Subnet C.
    Value: !Ref 'PublicSubnetC'
    Export:
      Name: "grpc-blog-public-subnet-c"
  AdhocAccessSecurityGroup:
    Description: Use this security group ID for the these blog services.
    Value: !GetAtt 'AdhocAccessSecurityGroup.GroupId'
    Export:
      Name: "grpc-blog-securitygroup-id"
  VPCID:
    Description: Use this VPC ID for all your services that are created in this blog.
    Value: !Ref 'VPC'
    Export:
      Name: "grpc-blog-vpc-id"