ECS-ALB.yaml

AWSTemplateFormatVersion: 2010-09-09
Description: AWS CloudFormation template to create an ECS Cluster, Task Definition, Service, Task with nginx image in private subnet, 
ALB, Security Groups.(Dependency Network.yaml)
Parameters:
  ECSClusterName:
    Type: String
    Description: Name of the ECS Cluster
    Default: demo-ecs-cluster
  
Resources:
  # Creating Access Role for ECS-Tasks
  ExecutionRole:
    Type: AWS::IAM::Role
    Properties:
      RoleName: ECS-Task-ExecutionRole
      AssumeRolePolicyDocument:
        Statement:
          - Effect: Allow
            Principal:
              Service: ecs-tasks.amazonaws.com
            Action: 'sts:AssumeRole'
      ManagedPolicyArns:
        - 'arn:aws:iam::aws:policy/service-role/AmazonECSTaskExecutionRolePolicy'

# Creating ECS Cluster
  MyECSCluster:
    Type: 'AWS::ECS::Cluster'
    Properties:
      ClusterName: !Ref ECSClusterName
      CapacityProviders:
        - FARGATE
        - FARGATE_SPOT
      ClusterSettings:
        - Name: containerInsights
          Value: disabled
      Configuration:
        ExecuteCommandConfiguration:
          Logging: DEFAULT
      ServiceConnectDefaults:
        Namespace: !Ref ECSClusterName

# Creating ECS Task definition
  MyTaskDefinition:
    Type: AWS::ECS::TaskDefinition
    Properties:
      Family: demo-task-definition
      NetworkMode: awsvpc
      RequiresCompatibilities:
        - FARGATE
      ExecutionRoleArn: !Ref ExecutionRole
      # TaskRoleArn: <your-task-role-arn>
      ContainerDefinitions:
        - Name: my-container
          Image: 'nginx:latest'
          PortMappings:
            - ContainerPort: 80
              Protocol: tcp
              AppProtocol: http
              HostPort: 80
      RuntimePlatform:
        CpuArchitecture: X86_64
        OperatingSystemFamily: LINUX    
      Memory: 512
      Cpu: 256

# Creating ECS Service
  MyService:
    Type: AWS::ECS::Service
    DependsOn: LoadBalancerListener
    Properties:
      Cluster: !Ref MyECSCluster
      TaskDefinition: !Ref MyTaskDefinition
      DesiredCount: 2
      LaunchType: FARGATE
      NetworkConfiguration:
        AwsvpcConfiguration:
          AssignPublicIp: DISABLED
          SecurityGroups:
            - !Ref MyECSSecurityGroup
          Subnets:
            - !ImportValue PrivateSubnet1Id
            - !ImportValue PrivateSubnet2Id
      LoadBalancers:
        - ContainerName: my-container
          ContainerPort: 80
          TargetGroupArn: !Ref TargetGroup      

# Creating Security Group for Load Balancer
  LoadBalancerSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupName: ALB-SG
      GroupDescription: "Security Group for Load Balancer"
      VpcId: !ImportValue VPCId
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: 80
          ToPort: 80
          CidrIp: 0.0.0.0/0

# Creating ECS Security Group
  MyECSSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupName: ECS-SG
      GroupDescription: "security group for ECS"
      VpcId: !ImportValue VPCId
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: 80
          ToPort: 80
          SourceSecurityGroupId: !Ref LoadBalancerSecurityGroup

  # Creating an Application LoadBalancer
  LoadBalancer:
    Type: AWS::ElasticLoadBalancingV2::LoadBalancer
    Properties: 
      IpAddressType: ipv4
      Name: ECS-LoadBalancer
      Scheme: internet-facing
      SecurityGroups:
        - !Ref LoadBalancerSecurityGroup
      Subnets: 
        - !ImportValue PublicSubnet1Id
        - !ImportValue PublicSubnet2Id
      Type: application

  # Create a TargetGroup for HTTP port 80
  TargetGroup:
    Type: AWS::ElasticLoadBalancingV2::TargetGroup
    Properties:
      Name: ECS-TargetGroup
      Port: 80
      Protocol: HTTP
      TargetType: ip
      VpcId: !ImportValue VPCId
      HealthCheckIntervalSeconds: 30
      HealthCheckPath: /
      HealthCheckProtocol: HTTP
      HealthCheckTimeoutSeconds: 10
      HealthyThresholdCount: 2
      UnhealthyThresholdCount: 5
      Matcher:
        HttpCode: 200      

  # Create a LoadBalancerListener and attach the TargetGroup and LoadBalancer
  LoadBalancerListener:
    Type: AWS::ElasticLoadBalancingV2::Listener
    Properties:
      DefaultActions: 
        - TargetGroupArn: !Ref TargetGroup
          Type: forward
      LoadBalancerArn: !Ref LoadBalancer
      Port: 80
      Protocol: HTTP     

Outputs:
  ECSCluster:
    Description: The created cluster.
    Value: !Ref MyECSCluster
  TaskDefinition:
    Description: The created Taskdefinition.
    Value: !Ref MyTaskDefinition 
  AlbDNSName:
    Description: DNS name of the Application Load Balancer
    Value: !Join [ "", [ "http://", !GetAtt LoadBalancer.DNSName ] ]