AWSTemplateFormatVersion: '2010-09-09'
Description: General use ECS Cluster
Parameters:
  VpcId:
    Type: AWS::EC2::VPC::Id
    Description: The id of the VPC the cluster will be in
    ConstraintDescription: VPC Id must begin with 'vpc-'
  SubnetIds:
    Type: List<AWS::EC2::Subnet::Id>
    Description: Comma seperated list of subnets for ECS instances to run in
  Project:
    Type: String
    Description: Project used in naming in tagging to associate with cluster
  Environment:
    Type: String
    Description: Environment used in naming and tagging to associate with cluster
  LatestAmiId :
    Type : 'AWS::SSM::Parameter::Value<AWS::EC2::Image::Id>'
    Default: '/aws/service/ecs/optimized-ami/amazon-linux-2/recommended/image_id'
  InstanceType:
    Type: String
    Default: "t3.micro"
  AsgMinSize:
    Type: Number
    Default: 0
  AsgMaxSize:
    Type: Number
    Default: 1
  AsgDesiredCapacity:
    Type: Number
    Default: 1
Resources:
  EcsCluster:
    Type: AWS::ECS::Cluster
    Properties: 
      ClusterName: !Sub "${Project}-${Environment}"

  EcsInstanceRole:
      Type: AWS::IAM::Role
      Properties:
        AssumeRolePolicyDocument:
          Version: '2012-10-17'
          Statement:
            - Action:
                - sts:AssumeRole
              Principal:
                Service:
                  - ec2.amazonaws.com 
              Effect: Allow
              Sid: ''
        Description: IAM role for instances in ECS cluster
        ManagedPolicyArns: 
          - "arn:aws:iam::aws:policy/service-role/AmazonEC2ContainerServiceforEC2Role"
        RoleName: !Sub "${Project}-ecs-role-${Environment}"
        Tags: 
          - Key: Environment
            Value: !Ref Environment
          - Key: Project
            Value: !Ref Project
        Path: /

  EcsRoleInstaceProfile:
    Type: AWS::IAM::InstanceProfile
    Properties: 
      InstanceProfileName: !Sub "${Project}-ecs-instance-profile-${Environment}"
      Path: /
      Roles: 
        - !Ref EcsInstanceRole

  EcsSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: ECS Allowed Ports
      VpcId: !Ref VpcId
      SecurityGroupIngress:
      - IpProtocol: icmp
        FromPort: '-1'
        ToPort: '-1'
        CidrIp: 0.0.0.0/0
      - IpProtocol: tcp
        FromPort: '0'
        ToPort: '65535'
        CidrIp: 0.0.0.0/0
      - IpProtocol: udp
        FromPort: '0'
        ToPort: '65535'
        CidrIp: 0.0.0.0/0
      SecurityGroupEgress:
      - IpProtocol: icmp
        FromPort: '-1'
        ToPort: '-1'
        CidrIp: 0.0.0.0/0
      - IpProtocol: tcp
        FromPort: '0'
        ToPort: '65535'
        CidrIp: 0.0.0.0/0
      - IpProtocol: udp
        FromPort: '0'
        ToPort: '65535'
        CidrIp: 0.0.0.0/0

  EcsInstanceLc:
    Type: AWS::AutoScaling::LaunchConfiguration
    Properties:
      ImageId: !Ref LatestAmiId
      InstanceType: !Ref InstanceType
      AssociatePublicIpAddress: true
      IamInstanceProfile: !Ref EcsRoleInstaceProfile
      KeyName: !Ref AWS::NoValue
      SecurityGroups:
      - !Ref EcsSecurityGroup
      BlockDeviceMappings:
      - DeviceName: /dev/xvdcz
        Ebs:
          VolumeSize: 22
          VolumeType: gp2
      UserData: !Base64
                Fn::Sub: |
                    #!/bin/bash
                    echo ECS_CLUSTER=${EcsCluster} >> /etc/ecs/ecs.config;
                    echo ECS_BACKEND_HOST= >> /etc/ecs/ecs.config;
  EcsInstanceAsg:
    Type: AWS::AutoScaling::AutoScalingGroup
    DependsOn: EcsCluster
    Properties:
        VPCZoneIdentifier: !Ref SubnetIds
        LaunchConfigurationName: !Ref EcsInstanceLc
        MinSize: !Ref AsgMinSize
        MaxSize: !Ref AsgMaxSize
        DesiredCapacity: !Ref AsgDesiredCapacity
        Tags:
        - Key: Name
          Value: !Sub "${Project}-ECS-ASG-${Environment}"
          PropagateAtLaunch: 'true'
        - Key: Environment
          Value: !Sub Environment
          PropagateAtLaunch: 'true'
        - Key: Project
          Value: !Sub Project
          PropagateAtLaunch: 'true'

Outputs:
  Cluster:
    Description: Name of the EcsCluster
    Value: !Ref EcsCluster
  ClusterArn:
    Description: Arn of the EcsCluster
    Value: !GetAtt EcsCluster.Arn