servers.yml

Description:  Udagram - servers
Parameters:
  EnvironmentName:
    Description: An environment name that will be prefixed to resource names
    Type: String

Resources:
  RootRole:
    Type: 'AWS::IAM::Role'
    Properties:
      AssumeRolePolicyDocument:
        Version: '2012-10-17'
        Statement:
          - Effect: 'Allow'
            Principal:
              Service:
                - 'ec2.amazonaws.com'
            Action:
              - 'sts:AssumeRole'
      Path: '/'
      Policies:
        - PolicyName: 'root'
          PolicyDocument:
            Version: '2012-10-17'
            Statement:
              - Effect: 'Allow'
                Action: '*'
                Resource: '*'

  RootInstanceProfile:
    Type: 'AWS::IAM::InstanceProfile'
    Properties:
      Path: '/'
      Roles:
        - Ref: 'RootRole'

  LBSecGroup: 
    Type: AWS::EC2::SecurityGroup
    Properties:
        GroupDescription: Allow http to our load balancer
        VpcId:
          Fn::ImportValue:
            !Sub "${EnvironmentName}-VPCID"
        SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: 80
          ToPort: 80
          CidrIp: 0.0.0.0/0
        SecurityGroupEgress:
        - IpProtocol: tcp
          FromPort: 80
          ToPort: 80
          CidrIp: 0.0.0.0/0
    
  WebServerSecGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
        GroupDescription: Allow http to our hosts
        VpcId:
          Fn::ImportValue:
            !Sub "${EnvironmentName}-VPCID"
        SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: 80
          ToPort: 80
          CidrIp: 0.0.0.0/0 
        SecurityGroupEgress:
        - IpProtocol: tcp
          FromPort: 0
          ToPort: 65535
          CidrIp: 0.0.0.0/0

  WebAppLaunchConfig:
    Type: AWS::AutoScaling::LaunchConfiguration
    Properties:
      UserData:
        Fn::Base64: !Sub |
          #!/bin/bash
          apt-get update -y
          apt-get install unzip awscli -y
          apt-get install apache2 -y
          systemctl start apache2.service
          cd /var/www/html
          aws s3 cp s3://udacity-demo-1/udacity.zip .
          unzip -o udacity.zip
      ImageId: ami-06f2f779464715dc5
      IamInstanceProfile: 
        Ref: RootInstanceProfile
      SecurityGroups:
      - Ref: WebServerSecGroup
      InstanceType: t3.medium
      BlockDeviceMappings:
      - DeviceName: "/dev/sdk"
        Ebs:
          VolumeSize: '10'

  WebAppGroup:
    Type: AWS::AutoScaling::AutoScalingGroup
    Properties:
      VPCZoneIdentifier:
      - Fn::ImportValue:
          !Sub "${EnvironmentName}-PRIV-NETS"
      LaunchConfigurationName:
        Ref: WebAppLaunchConfig
      MinSize: '4'
      MaxSize: '4'
      TargetGroupARNs:
        - Ref: WebAppTargetGroup
  
  WebAppTargetGroup:
    Type: AWS::ElasticLoadBalancingV2::TargetGroup
    Properties:
      HealthCheckIntervalSeconds: 10
      HealthCheckPath: /
      HealthCheckProtocol: HTTP
      HealthCheckTimeoutSeconds: 8
      HealthyThresholdCount: 2
      Port: 80
      Protocol: HTTP
      UnhealthyThresholdCount: 5
      VpcId:
        Fn::ImportValue:
          Fn::Sub: "${EnvironmentName}-VPCID"

  WebAppLB:
    Type: AWS::ElasticLoadBalancingV2::LoadBalancer
    Properties:
      Subnets:
        - Fn::ImportValue: !Sub "${EnvironmentName}-PUB1-SN"
        - Fn::ImportValue: !Sub "${EnvironmentName}-PUB2-SN"
      SecurityGroups:
        - Ref: LBSecGroup

  Listener:
    Type: AWS::ElasticLoadBalancingV2::Listener
    Properties:
      DefaultActions:
      -   Type: forward
          TargetGroupArn: 
              Ref: WebAppTargetGroup
      LoadBalancerArn: !Ref WebAppLB
      Port: 80
      Protocol: HTTP

  ALBListenerRule:
    Type: AWS::ElasticLoadBalancingV2::ListenerRule
    Properties:
      Actions:
      -   Type: forward
          TargetGroupArn: !Ref WebAppTargetGroup
      Conditions:
      -   Field: path-pattern
          Values: [/]
      ListenerArn: !Ref Listener
      Priority: 1

Outputs:
  LoadBalancerURL:
    Description: The public url to load balancer
    Value: !Join [ "", ["http://" , !GetAtt WebAppLB.DNSName ]]