server.yaml

Description: >
    This templates deploys server infrastructures for an apache webserver.

Parameters:

    EnvName:
        Description: An environment name, linked to the network stack, that will be prefixed to resource names
        Type: String
    UbuntuAMI:
        Description: The amazon machine image ID for an Ubuntu machine on AWS
        Type: String
        Default: ami-052efd3df9dad4825
    S3BucketName:
        Description: The S3 bucket name to retrieve the web server code from
        Type: String
Resources:
  S3ReadOnlyRole:
    Type: 'AWS::IAM::Role'
    Properties:
      ManagedPolicyArns:
        - "arn:aws:iam::aws:policy/AmazonS3ReadOnlyAccess"
        - "arn:aws:iam::aws:policy/AmazonSSMFullAccess"
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service:
              - ec2.amazonaws.com
            Action:
              - 'sts:AssumeRole'
      Path: "/"

  WebAppProfile:
    Type: AWS::IAM::InstanceProfile
    Properties: 
      Roles:
        - !Ref S3ReadOnlyRole
  LBSecGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Allow http to our load balancer
      VpcId:
        Fn::ImportValue:
          !Sub "${EnvName}-VPCID"
      SecurityGroupIngress:
      - IpProtocol: tcp
        FromPort: 80
        ToPort: 80
        CidrIp: 0.0.0.0/0
      SecurityGroupEgress:
      - IpProtocol: tcp
        FromPort: 80
        ToPort: 80
        CidrIp: 0.0.0.0/0
  WebServerSecGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Allow http to our hosts and SSH from local only
      VpcId:
        Fn::ImportValue:
          !Sub "${EnvName}-VPCID"
      SecurityGroupIngress:
      - IpProtocol: tcp
        FromPort: 80
        ToPort: 80
        CidrIp: 0.0.0.0/0
      - IpProtocol: tcp
        FromPort: 22
        ToPort: 22
        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 apache2 -y
         systemctl start apache2.service
         sudo apt install awscli -y
         cd /var/www/html
         aws s3 cp s3://${S3BucketName} ./  --recursive
      ImageId: !Ref UbuntuAMI
      IamInstanceProfile: !Ref WebAppProfile
      SecurityGroups:
      - Ref: WebServerSecGroup
      InstanceType: t3.medium
      BlockDeviceMappings:
      - DeviceName: "/dev/sdk"
        Ebs:
          VolumeSize: '10'
  WebAppGroup:
    Type: AWS::AutoScaling::AutoScalingGroup
    Properties:
      VPCZoneIdentifier:
      - Fn::ImportValue: 
          !Sub "${EnvName}-PRIV-NETS"
      LaunchConfigurationName:
        Ref: WebAppLaunchConfig
      MinSize: '4'
      MaxSize: '5'
      TargetGroupARNs:
      - Ref: WebAppTargetGroup
  WebAppLB:
    Type: AWS::ElasticLoadBalancingV2::LoadBalancer
    Properties:
      Subnets:
      - Fn::ImportValue: !Sub "${EnvName}-PUB1-SN"
      - Fn::ImportValue: !Sub "${EnvName}-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
  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: "${EnvName}-VPCID"
Outputs: 

    LoadBalancerDNSName: 
        Description: A reference to the Elastic Load Balancer's URL
        Value: !Sub 
          - http://${Domain}
          - Domain: !GetAtt WebAppLB.DNSName
        Export:
          Name: !Sub ${EnvName}-ELB-DNSName