heat_template_version: 2013-05-23

description: >
  A HOT template that holds an ASRG of a stack

parameters:
  KeyName:
    type: string
    description: Name of an existing key pair to use for the instance
  flavor:
    type: string
    description: Instance type for the instance to be created
    default: m1.small
    constraints:
      - allowed_values: [m1.tiny, m1.small, m1.medium, m1.large]
        description: Value must be one of 'm1.tiny', 'm1.small', 'm1.medium', or 'm1.large'
  image:
    type: string
    default: F17-x86_64-cfntools
    description: ID of the image to use for the instance
  meter_group:
    type: string
    description: value of VM's metering.instgroup metadatum
    default: ogrp

resources:
  my_group:
    type: OS::Heat::AutoScalingGroup
    properties:
      resource:
        type: AWS::CloudFormation::Stack
        properties:
          Parameters:
            KeyName: { get_param: KeyName }
            image: { get_param: image }
            flavor: { get_param: flavor }
            meter_group: { get_param: meter_group }
          TemplateURL: http://my.favorite.server/path/VM_with_EBS.yaml
      min_size: 1
      desired_capacity: 3
      max_size: 5

  control_group:
    type: AWS::AutoScaling::AutoScalingGroup
    properties:
      AvailabilityZones: {'Fn::GetAZs': ''}
      LaunchConfigurationName: {get_resource: LaunchConfig}
      MinSize: '1'
      DesiredCapacity: 2
      MaxSize: '3'
      Tags:
      - {Key: metering.server_group, Value: control_group}

  LaunchConfig:
    type: AWS::AutoScaling::LaunchConfiguration
    properties:
      ImageId: {get_param: image}
      InstanceType: {get_param: flavor}
      KeyName: { get_param: KeyName }

  ControlScaleUpPolicy:
    type: AWS::AutoScaling::ScalingPolicy
    properties:
      AdjustmentType: ChangeInCapacity
      AutoScalingGroupName: {get_resource: control_group}
      Cooldown: 60
      ScalingAdjustment: '1'

  ControlScaleDnPolicy:
    type: AWS::AutoScaling::ScalingPolicy
    properties:
      AdjustmentType: ChangeInCapacity
      AutoScalingGroupName: {get_resource: control_group}
      Cooldown: 60
      ScalingAdjustment: -1

  WebServerScaleUpPolicy:
    type: AWS::AutoScaling::ScalingPolicy
    properties:
      AdjustmentType: ChangeInCapacity
      AutoScalingGroupName: {get_resource: my_group}
      Cooldown: 60
      ScalingAdjustment: '1'

  WebServerScaleDnPolicy:
    type: AWS::AutoScaling::ScalingPolicy
    properties:
      AdjustmentType: ChangeInCapacity
      AutoScalingGroupName: {get_resource: my_group}
      Cooldown: 60
      ScalingAdjustment: '-11'

outputs:
  group_id:
    description: the ID of the ASG
    value: { get_resource: my_group }
  control_up_url:
    value: {get_attr: [ControlScaleUpPolicy, AlarmUrl]}
  control_dn_url:
    value: {get_attr: [ControlScaleDnPolicy, AlarmUrl]}
  scale_up_url:
    value: {get_attr: [WebServerScaleUpPolicy, AlarmUrl]}
  scale_dn_url:
    value: {get_attr: [WebServerScaleDnPolicy, AlarmUrl]}