servers.yaml

Description: >
    Matembu Emmanuel Dominic / Project Challenge 2
    This template deploys a high-availability web app using apache while the static files
    are uploaded to the s3 bucket all through using CloudFormation project.
Parameters:
    EnvironmentName:
        Description: An environment name that will be prefixed to resource names.
        Type: String
    AMImage:
      Description: A name that will be prefixed to the name of an instance.
      Type: String
    BucketName:
      Type: String
      Description: The name of the S3 Bucket to create
Resources:
  S3Bucket:
    Type: AWS::S3::Bucket
    Properties:
      BucketName: !Ref BucketName
      AccessControl: PublicRead
      WebsiteConfiguration:
        IndexDocument: index.html
        ErrorDocument: error.html
    DeletionPolicy: Retain
  BucketPolicy:
    Type: AWS::S3::BucketPolicy
    Properties:
      PolicyDocument:
        Id: MyPolicy
        Version: 2012-10-17
        Statement:
          - Sid: PublicReadForGetBucketObjects
            Effect: Allow
            Principal: '*'
            Action: 's3:GetObject'
            Resource: !Join
              - ''
              - - 'arn:aws:s3:::'
                - !Ref BucketName
                - /*
      Bucket: !Ref BucketName
  LBSecGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Allow http to our load balancer
      VpcId:
        Fn::ImportValue:
          !Sub "${EnvironmentName}-VPCID"
      SecurityGroupIngress:
      - IpProtocol: tcp
        FromPort: 80
        ToPort: 80
        CidrIp: 0.0.0.0/0
      SecurityGroupEgress:
      - IpProtocol: tcp
        FromPort: 80
        ToPort: 80
        CidrIp: 0.0.0.0/0
  WebServerSecGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Allow http to our hosts and SSH from local only
      VpcId:
        Fn::ImportValue:
          !Sub "${EnvironmentName}-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
          sudo apt-get update -y
          sudo apt-get install apache2 -y
          sudo systemctl start apache2.service
          echo "<h1>CloudFormation Project Challenge Two<h1>" > /var/www/html/index.html
      ImageId: !Ref AMImage
      SecurityGroups:
      - Ref: WebServerSecGroup
      InstanceType: t3.medium
      BlockDeviceMappings:
      - DeviceName: "/dev/sdk"
        Ebs:
          VolumeSize: '10'
  WebAppGroup:
    Type: AWS::AutoScaling::AutoScalingGroup
    Properties:
      VPCZoneIdentifier:
      - Fn::ImportValue:
          !Sub "${EnvironmentName}-PRIV-NETS"
      LaunchConfigurationName:
        Ref: WebAppLaunchConfig
      MinSize: '3'
      MaxSize: '5'
      TargetGroupARNs:
      - Ref: WebAppTargetGroup
  WebAppLB:
    Type: AWS::ElasticLoadBalancingV2::LoadBalancer
    Properties:
      Subnets:
      - Fn::ImportValue: !Sub "${EnvironmentName}-PUB1-SN"
      - Fn::ImportValue: !Sub "${EnvironmentName}-PUB2-SN"
      SecurityGroups:
      - Ref: LBSecGroup
  Listener:
    Type: AWS::ElasticLoadBalancingV2::Listener
    Properties:
      DefaultActions:
      - Type: forward
        TargetGroupArn:
          Ref: WebAppTargetGroup
      LoadBalancerArn:
        Ref: WebAppLB
      Port: '80'
      Protocol: HTTP
  ALBListenerRule:
      Type: AWS::ElasticLoadBalancingV2::ListenerRule
      Properties:
        Actions:
        - Type: forward
          TargetGroupArn: !Ref 'WebAppTargetGroup'
        Conditions:
        - Field: path-pattern
          Values: [/]
        ListenerArn: !Ref 'Listener'
        Priority: 1
  WebAppTargetGroup:
    Type: AWS::ElasticLoadBalancingV2::TargetGroup
    Properties:
      HealthCheckIntervalSeconds: 10
      HealthCheckPath: /
      HealthCheckProtocol: HTTP
      HealthCheckTimeoutSeconds: 8
      HealthyThresholdCount: 2
      Port: 80
      Protocol: HTTP
      UnhealthyThresholdCount: 5
      VpcId:
        Fn::ImportValue:
          Fn::Sub: "${EnvironmentName}-VPCID"

Outputs:
  WebAppLoadBalancerDNSName:
    Description: DNS name or Public URL of the Load Balancer
    Value: !Join ["", ['http://', !GetAtt WebAppLB.DNSName]]
    Export:
      Name: !Sub ${EnvironmentName}-LB-DNSName
  WebsiteURL:
    Value: !GetAtt S3Bucket.WebsiteURL
    Description: URL for website hosted on S3
  S3BucketSecureURL:
    Value: !Join ["", ['http://', !GetAtt S3Bucket.DomainName]]
    Description: Name of S3 bucket to hold website content