AWSTemplateFormatVersion: 2010-09-09
Description: >-
  AWS CloudFormation Sample Template: This template demonstrates
  the creation of a DynamoDB cluster with  application AutoScaling. **WARNING** This template creates an numerous resources. You will be billed for the AWS resources used if you create a stack from this template."
Parameters:
  username:
    Type: String
  password:
    Type: String
  Role:
    Type: String
    Description: An IAM role arn that allows the CFN template to modify resources on your behalf
  ScalePolicyName:
    Type: String
    Default: ScaleMyRide
Resources:
  RDSCluster:
    Type: AWS::RDS::DBCluster
    Properties:
      MasterUsername:
        Ref: username
      MasterUserPassword:
        Ref: password
      Engine: aurora
      DBClusterParameterGroupName:
        Ref: RDSDBClusterParameterGroup
  RDSDBInstance1:
    Type: AWS::RDS::DBInstance
    Properties:
      DBParameterGroupName:
        Ref: RDSDBParameterGroup
      Engine: aurora
      DBClusterIdentifier:
        Ref: RDSCluster
      PubliclyAccessible: 'true'
      DBInstanceClass: db.t2.small
  RDSDBInstance2:
    Type: AWS::RDS::DBInstance
    Properties:
      DBParameterGroupName:
        Ref: RDSDBParameterGroup
      Engine: aurora
      DBClusterIdentifier:
        Ref: RDSCluster
      PubliclyAccessible: 'true'
      DBInstanceClass: db.t2.small
  RDSDBClusterParameterGroup:
    Type: AWS::RDS::DBClusterParameterGroup
    Properties:
      Description: CloudFormation Sample Aurora Cluster Parameter Group
      Family: aurora5.6
      Parameters:
        time_zone: US/Eastern
  RDSDBParameterGroup:
    Type: AWS::RDS::DBParameterGroup
    Properties:
      Description: CloudFormation Sample Aurora Parameter Group
      Family: aurora5.6
      Parameters:
        sql_mode: IGNORE_SPACE
  ClusterAutoScaleTarget:
    Type: AWS::ApplicationAutoScaling::ScalableTarget
    Properties:
      MaxCapacity: 4
      MinCapacity: 1
      ResourceId:
        !Join
          - ''
          - - 'cluster:'
            - !Ref RDSCluster
      RoleARN: !Ref Role
      ScalableDimension: rds:cluster:ReadReplicaCount
      ServiceNamespace: rds
  ClusterAutoScalePolicy:
    DependsOn: ClusterAutoScaleTarget
    Type: "AWS::ApplicationAutoScaling::ScalingPolicy"
    Properties:
      PolicyName: !Ref ScalePolicyName
      PolicyType: StepScaling
      ResourceId:
        !Join
          - ''
          - - 'cluster:'
            - !Ref RDSCluster
      ScalableDimension: rds:cluster:ReadReplicaCount
      ServiceNamespace: rds
      StepScalingPolicyConfiguration:
        AdjustmentType: ChangeInCapacity
        Cooldown: 60
        StepAdjustments:
          - ScalingAdjustment: 1
            MetricIntervalLowerBound: 1