heat-templates/cfn/F17/AutoScalingCeilometer.yaml

HeatTemplateFormatVersion: '2012-12-12'
Description: Creates an autoscaling wordpress application using deprecated Ceilometer API.
Parameters:
  KeyName:
    Description: Name of an existing EC2 KeyPair to enable SSH access to the instances
    Type: String
  InstanceType:
    Description: WebServer EC2 instance type
    Type: String
    Default: m1.small
    AllowedValues: [m1.tiny, m1.small, m1.medium, m1.large, m1.xlarge]
    ConstraintDescription: must be a valid EC2 instance type.
  ImageId:
    Description: the name or uuid of the image in glance
    Type: String
    Default: F17-x86_64-cfntools
  DBUsername: {Default: admin, NoEcho: 'true',
    Description: The WordPress database admin account username, Type: String,
    MinLength: '1', MaxLength: '16', AllowedPattern: '[a-zA-Z][a-zA-Z0-9]*',
    ConstraintDescription: must begin with a letter and contain only
      alphanumeric characters.}
  DBPassword: {Default: admin, NoEcho: 'true',
    Description: The WordPress database admin account password, Type: String,
    MinLength: '1', MaxLength: '41', AllowedPattern: '[a-zA-Z0-9]*',
    ConstraintDescription: must contain only alphanumeric characters.}
  DBRootPassword: {Default: admin, NoEcho: 'true',
    Description: Root password for MySQL, Type: String,
    MinLength: '1', MaxLength: '41', AllowedPattern: '[a-zA-Z0-9]*',
    ConstraintDescription: must contain only alphanumeric characters.}
Resources:
  CfnUser: {Type: 'AWS::IAM::User'}
  WebServerKeys:
    Type: AWS::IAM::AccessKey
    Properties:
      UserName: {Ref: CfnUser}
  WebServerGroup:
    Type: AWS::AutoScaling::AutoScalingGroup
    Properties:
      AvailabilityZones: {'Fn::GetAZs': ''}
      LaunchConfigurationName: {Ref: LaunchConfig}
      MinSize: '1'
      MaxSize: '3'
      LoadBalancerNames:
      - {Ref: ElasticLoadBalancer}
  WebServerScaleUpPolicy:
    Type: AWS::AutoScaling::ScalingPolicy
    Properties:
      AdjustmentType: ChangeInCapacity
      AutoScalingGroupName: {Ref: WebServerGroup}
      Cooldown: '60'
      ScalingAdjustment: '1'
  WebServerScaleDownPolicy:
    Type: AWS::AutoScaling::ScalingPolicy
    Properties:
      AdjustmentType: ChangeInCapacity
      AutoScalingGroupName: {Ref: WebServerGroup}
      Cooldown: '60'
      ScalingAdjustment: '-1'
  CPUAlarmHigh:
    Type: OS::Ceilometer::Alarm
    Properties:
      description: Scale-up if the average CPU > 50% for 1 minute
      meter_name: cpu_util
      statistic: avg
      period: '60'
      evaluation_periods: '1'
      threshold: '50'
      alarm_actions:
      - {"Fn::GetAtt": [WebServerScaleUpPolicy, AlarmUrl]}
      matching_metadata: {'metadata.user_metadata.groupname': {Ref: 'WebServerGroup'}}
      comparison_operator: gt
  CPUAlarmLow:
    Type: OS::Ceilometer::Alarm
    Properties:
      description: Scale-down if the average CPU < 15% for 1 minute
      meter_name: cpu_util
      statistic: avg
      period: '60'
      evaluation_periods: '1'
      threshold: '15'
      alarm_actions:
      - {"Fn::GetAtt": [WebServerScaleDownPolicy, AlarmUrl]}
      matching_metadata: {'metadata.user_metadata.groupname': {Ref: 'WebServerGroup'}}
      comparison_operator: lt
  ElasticLoadBalancer:
    Type: AWS::ElasticLoadBalancing::LoadBalancer
    Properties:
      AvailabilityZones: {'Fn::GetAZs': ''}
      Listeners:
      - {LoadBalancerPort: '80', InstancePort: '80',
        Protocol: HTTP}
      HealthCheck: {Target: 'HTTP:80/', HealthyThreshold: '3',
        UnhealthyThreshold: '5', Interval: '30', Timeout: '5'}
  LaunchConfig:
    Type: AWS::AutoScaling::LaunchConfiguration
    Metadata:
      AWS::CloudFormation::Init:
        config:
          files:
            /etc/cfn/cfn-credentials:
              content:
                'Fn::Replace':
                - WebServerKeys: {Ref: WebServerKeys}
                  WebSecretKey: {'Fn::GetAtt': [WebServerKeys, SecretAccessKey]}
                - |
                  AWSAccessKeyId=WebServerKeys
                  AWSSecretKey=WebSecretKey                  
              mode: '000400'
              owner: root
              group: root
            /tmp/setup.mysql:
              content:
                'Fn::Replace':
                - DBPassword: {Ref: DBPassword}
                  DBUsername: {Ref: DBUsername}
                - |
                  CREATE DATABASE wordpress;
                  GRANT ALL PRIVILEGES ON wordpress .* TO 'DBUsername'@'localhost' IDENTIFIED BY 'DBPassword';
                  FLUSH PRIVILEGES;
                  EXIT                  
              mode: '000644'
              owner: root
              group: root
          packages:
            yum:
              mysql: []
              mysql-server: []
              httpd: []
              wordpress: []
          services:
            systemd:
              mysqld: {enabled: 'true', ensureRunning: 'true'}
              httpd: {enabled: 'true', ensureRunning: 'true'}
    Properties:
      ImageId: {Ref: ImageId}
      InstanceType: {Ref: InstanceType}
      KeyName: {Ref: KeyName}
      UserData:
        Fn::Base64:
          Fn::Replace:
          - 'AWS::StackName': {Ref: 'AWS::StackName'}
            'AWS::Region': {Ref: 'AWS::Region'}
            DBRootPassword: {Ref: DBRootPassword}
            DBPassword: {Ref: DBPassword}
            DBUsername: {Ref: DBUsername}
          - |
            #!/bin/bash -v
            /opt/aws/bin/cfn-init -s AWS::StackName -r LaunchConfig --region AWS::Region
            # Setup MySQL root password and create a user
            mysqladmin -u root password DBRootPassword
            mysql -u root --password=DBRootPassword < /tmp/setup.mysql
            sed -i "/Deny from All/d" /etc/httpd/conf.d/wordpress.conf
            sed -i "/Deny from all/d" /etc/httpd/conf.d/wordpress.conf
            sed --in-place --e s/database_name_here/wordpress/ --e s/username_here/DBUsername/ --e s/password_here/DBPassword/ /usr/share/wordpress/wp-config.php
            systemctl restart httpd.service            
Outputs:
  URL:
    Description: The URL of the website
    Value:
      Fn::Replace:
      - IpAddress: {'Fn::GetAtt': [ElasticLoadBalancer, DNSName]}
      - http://IpAddress/wordpress