---
AWSTemplateFormatVersion: 2010-09-09

Description: Amazon Elastic File System - Add data to grow existing file system

Metadata:
  Authors:
    Description: Darryl Osborne (darrylo@amazon.com)
  License:
    Description: 'Copyright 2018 Amazon.com, Inc. and its affiliates. All Rights Reserved.
      SPDX-License-Identifier: MIT-0'
  AWS::CloudFormation::Interface:
    ParameterGroups:
    - Label:
        default: Amazon EFS Parameters
      Parameters:
        - ElasticFileSystem
        - Growth
        - Success
        - SecurityGroup
        - NumberOfSubnets
        - Subnet
        - InstanceType
        - KeyName
    ParameterLabels:
      ElasticFileSystem:
        default: File System Id
      Growth:
        default: Add data (GiB)
      InstanceType:
        default: Instance Type
      KeyName:
        default: Existing Key Pair
      NumberOfSubnets:
        default: Number of subnets
      SecurityGroup:
        default: Security Group
      Subnet:
        default: Subnets
      Success:
        default: "Success on:"

Parameters:
  ElasticFileSystem:
    AllowedPattern: ^(fs-)([a-z0-9]{8})$
    Description: The Amazon EFS file system id.
    Type: String   
  Growth:
    ConstraintDescription: Must be an integer.
    Description: Amount of dummy data (GiB) to add to the file system (min 0, max 6144). Amazon EFS storage charges apply. 
    MaxValue: 6144
    MinValue: 0
    Type: Number
  InstanceType:
    AllowedValues:
    - t2.nano 
    - t2.micro 
    - t2.small 
    - t2.medium 
    - t2.large 
    - t2.xlarge 
    - t2.2xlarge 
    - m3.medium 
    - m3.large 
    - m3.xlarge 
    - m3.2xlarge 
    - m4.large 
    - m4.xlarge 
    - m4.2xlarge 
    - m4.4xlarge 
    - m4.10xlarge 
    - m4.16xlarge 
    - m5.large 
    - m5.xlarge 
    - m5.2xlarge 
    - m5.4xlarge 
    - m5.12xlarge 
    - m5.24xlarge 
    - c3.large 
    - c3.xlarge 
    - c3.2xlarge 
    - c3.4xlarge 
    - c3.8xlarge 
    - c4.large 
    - c4.xlarge 
    - c4.2xlarge 
    - c4.4xlarge 
    - c4.8xlarge 
    - c5.large 
    - c5.xlarge 
    - c5.2xlarge 
    - c5.4xlarge 
    - c5.9xlarge 
    - c5.18xlarge
    - r3.large 
    - r3.xlarge 
    - r3.2xlarge 
    - r3.4xlarge 
    - r3.8xlarge 
    - r4.large 
    - r4.xlarge 
    - r4.2xlarge 
    - r4.4xlarge 
    - r4.8xlarge 
    - r4.16xlarge 
    - x1.16xlarge 
    - x1.32xlarge 
    - x1e.xlarge 
    - x1e.2xlarge 
    - x1e.4xlarge 
    - x1e.8xlarge 
    - x1e.16xlarge 
    - x1e.32xlarge
    - d2.xlarge 
    - d2.2xlarge 
    - d2.4xlarge 
    - d2.8xlarge 
    - h1.2xlarge 
    - h1.4xlarge 
    - h1.8xlarge 
    - h1.16xlarge 
    - i2.xlarge 
    - i2.2xlarge 
    - i2.4xlarge 
    - i2.8xlarge 
    - i3.large 
    - i3.xlarge 
    - i3.2xlarge 
    - i3.4xlarge 
    - i3.8xlarge 
    - i3.16xlarge
    - f1.2xlarge 
    - f1.16xlarge 
    - g2.2xlarge 
    - g2.8xlarge 
    - g3.4xlarge 
    - g3.8xlarge 
    - g3.16xlarge 
    - p2.xlarge 
    - p2.8xlarge 
    - p2.16xlarge 
    - p3.2xlarge 
    - p3.8xlarge 
    - p3.16xlarge
    ConstraintDescription: Must be a valid Amazon EC2 instance type.
    Default: c5.large
    Description: The Amazon EC2 instance type that adds data to the file system.
    Type: String
  KeyName:
    Description: Name of an existing EC2 key pair
    Type: AWS::EC2::KeyPair::KeyName
  NumberOfSubnets:
    AllowedValues:
    - 1
    - 2
    - 3
    - 4
    - 5
    - 6
    Default: 3
    Description: Number of subnets. This must match your selections in the list of Subnets below.
    Type: String 
  SecurityGroup:
    Description: Select the EC2 security group that allows SSH access to the instance and NFS access to the EFS file system.
    Type: AWS::EC2::SecurityGroup::Id
  Subnet:
    Description: Select existing public subnets.
    Type: List<AWS::EC2::Subnet::Id>
  Success:
    AllowedValues:
      - "Data-add start"
      - "Data-add complete"
    Default: "Data-add complete"
    Description: Select which event signals success.
    Type: String

Conditions:

  NumberofSubnets1:
      !Equals [ 1, !Ref NumberOfSubnets ]
  NumberofSubnets2:
      !Equals [ 2, !Ref NumberOfSubnets ]
  NumberofSubnets3:
      !Equals [ 3, !Ref NumberOfSubnets ]
  NumberofSubnets4:
      !Equals [ 4, !Ref NumberOfSubnets ]
  NumberofSubnets5:
      !Equals [ 5, !Ref NumberOfSubnets ]
  SuccessStart:
    !Equals [ 'Data-add start', !Ref Success ]

Mappings:
  RegionMap:
    us-east-1:
      AMI: ami-97785bed
    us-east-2:
      AMI: ami-f63b1193
    us-west-2:
      AMI: ami-f2d3638a
    us-west-1:
      AMI: ami-824c4ee2
    ca-central-1:
      AMI: ami-a954d1cd
    eu-west-1:
      AMI: ami-d834aba1
    eu-west-2:
      AMI: ami-403e2524
    eu-west-3:
      AMI: ami-8ee056f3
    eu-central-1:
      AMI: ami-5652ce39
    ap-southeast-1:
      AMI: ami-68097514
    ap-northeast-2:
      AMI: ami-863090e8
    ap-northeast-1:
      AMI: ami-ceafcba8
    ap-southeast-2:
      AMI: ami-942dd1f6
    ap-south-1:
      AMI: ami-531a4c3c
    sa-east-1:
      AMI: ami-84175ae8

Resources:
  InstanceProfile:
    Type: AWS::IAM::InstanceProfile
    Properties:
      Path: /
      Roles:
      - !Ref InstanceRole
  InstanceRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
        - Effect: Allow
          Principal:
            Service:
            - ec2.amazonaws.com
          Action:
          - sts:AssumeRole
      Path: /
      Policies:
      - PolicyName: !Join [ '', [ 'policy-', !Ref 'AWS::StackName' ] ]
        PolicyDocument:
          Version: 2012-10-17
          Statement:
          - Effect: Allow
            Action:
              - autoscaling:DescribeAutoScalingGroups
              - autoscaling:DescribeAutoScalingInstances
              - autoscaling:DescribePolicies
              - autoscaling:UpdateAutoScalingGroup
            Resource: '*'
  AutoScalingGroup:
    Type: AWS::AutoScaling::AutoScalingGroup
    Properties:
      Cooldown: 60
      HealthCheckGracePeriod: 120
      HealthCheckType: EC2
      LaunchConfigurationName: !Ref LaunchConfiguration
      MaxSize: 1
      MinSize: 0
      DesiredCapacity: 1
      Tags:
        - Key: Name
          Value: !Join [ '', [ 'EFS ', !Ref ElasticFileSystem, ' data load... will auto terminate.' ] ]
          PropagateAtLaunch: true
      VPCZoneIdentifier:
        !If
          [ NumberofSubnets1,
          [ !Select [ 0, !Ref Subnet ] ],
          !If
            [ NumberofSubnets2,
            [ !Select [ 0, !Ref Subnet ], !Select [ 1, !Ref Subnet ] ],
            !If
              [ NumberofSubnets3,
              [ !Select [ 0, !Ref Subnet ], !Select [ 1, !Ref Subnet ], !Select [ 2, !Ref Subnet ] ],
              !If
                [ NumberofSubnets4,
                [ !Select [ 0, !Ref Subnet ], !Select [ 1, !Ref Subnet ], !Select [ 2, !Ref Subnet ], !Select [ 3, !Ref Subnet ] ],
                !If
                  [ NumberofSubnets5,
                  [ !Select [ 0, !Ref Subnet ], !Select [ 1, !Ref Subnet ], !Select [ 2, !Ref Subnet ], !Select [ 3, !Ref Subnet ], !Select [ 4, !Ref Subnet ] ],
                  [ !Select [ 0, !Ref Subnet ], !Select [ 1, !Ref Subnet ], !Select [ 2, !Ref Subnet ], !Select [ 3, !Ref Subnet ], !Select [ 4, !Ref Subnet ], !Select [ 5, !Ref Subnet ] ]
                  ]
                ]
              ]
            ]
          ]
    CreationPolicy:
      ResourceSignal:
        Count: !If [ SuccessStart, 0 , 1 ]
        Timeout: PT12H
    UpdatePolicy:
      AutoScalingReplacingUpdate:
        WillReplace: true
  AutoScalingPolicy:
    Type: AWS::AutoScaling::ScalingPolicy
    Properties:
      AdjustmentType: ChangeInCapacity
      AutoScalingGroupName: !Ref AutoScalingGroup
      Cooldown: 60
      PolicyType: SimpleScaling
      ScalingAdjustment: 1
  LaunchConfiguration:
    Type: AWS::AutoScaling::LaunchConfiguration
    Metadata:
      AWS::CloudFormation::Init:
        configSets:
          efs_add_storage:
            - efs-add-storage
        efs-add-storage:
          files:              
            /tmp/efs-add-storage.sh:
              content: !Sub |
                #!/bin/bash -x

                FILE_SYSTEM_ID=$1
                DATA_DIRECTORY=$2
                GROWTH=$3

                if [ $# -lt 3 ]; then
                  echo "Invalid # of arguments. Require: file system id, data directory, file system growth (GiB) "
                  exit 0
                fi

                # get region from instance meta-data
                availabilityzone=$(curl -s http://169.254.169.254/latest/meta-data/placement/availability-zone)
                region=${!availabilityzone:0:-1}

                # get instance id
                instance_id=$(curl -s http://169.254.169.254/latest/meta-data/instance-id)

                # get autoscaling group name
                asg_name=$(aws autoscaling describe-auto-scaling-instances --instance-ids $instance_id --region $region --output text --query 'AutoScalingInstances[0].AutoScalingGroupName')

                # set the number of threads to the number of vcpus
                threads=$(( $(nproc --all) * 8 ))

                # wait for file system DNS name to be propagated
                results=1
                while [[ $results != 0 ]]; do
                  nslookup $FILE_SYSTEM_ID.efs.$region.amazonaws.com
                  results=$?
                  if [[ results = 1 ]]; then
                    sleep 30
                  fi
                done

                # mount file system
                sudo mkdir -p /$FILE_SYSTEM_ID
                sudo chown ec2-user:ec2-user /$FILE_SYSTEM_ID
                sudo mountpoint -q /$FILE_SYSTEM_ID || sudo mount -t nfs4 -o nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2 $FILE_SYSTEM_ID.efs.$region.amazonaws.com:/ /$FILE_SYSTEM_ID

                # create directory if not exists
                sudo mkdir -p /$FILE_SYSTEM_ID/$DATA_DIRECTORY
                sudo chown ec2-user:ec2-user /$FILE_SYSTEM_ID/$DATA_DIRECTORY

                # dd 1GiB files to file system to match DATA_SIZE
                files=$GROWTH
                if [ $(( $files / $threads )) == 0 ];
                  then
                    runs=0
                    parallel_threads=$(( $files % $threads ))
                  else
                    runs=$(( $files / $threads ))
                    parallel_threads=$threads
                fi
                while [ $runs -ge 0 ]; do
                  if [ $runs == 0 ];
                    then
                      parallel_threads=$(( $files % $threads ))
                      seq 0 $(( $parallel_threads - 1 )) | parallel --will-cite -j $parallel_threads --compress dd if=/dev/zero of=/$FILE_SYSTEM_ID/$DATA_DIRECTORY/1G-dd-$(date +%Y%m%d%H%M%S.%3N)-{} bs=1M count=1024 oflag=sync
                      runs=$(($runs-1))
                    else
                      seq 0 $(( $parallel_threads - 1 )) | parallel --will-cite -j $parallel_threads --compress dd if=/dev/zero of=/$FILE_SYSTEM_ID/$DATA_DIRECTORY/1G-dd-$(date +%Y%m%d%H%M%S.%3N)-{} bs=1M count=1024 oflag=sync
                      runs=$(($runs-1))
                  fi
                done

                # set ASG to zero which terminates instance
                aws autoscaling update-auto-scaling-group --auto-scaling-group-name $asg_name --desired-capacity 0 --region $region

              mode: 000777
              owner: root
              group: root             
    Properties:
      BlockDeviceMappings:
        - DeviceName: /dev/xvda
          Ebs:
            DeleteOnTermination: true
            VolumeSize: 10
            VolumeType: gp2
      IamInstanceProfile: !Ref InstanceProfile
      ImageId: !FindInMap [ RegionMap, !Ref 'AWS::Region', AMI ]
      InstanceMonitoring: true
      InstanceType: !Ref InstanceType
      KeyName: !Ref KeyName
      SecurityGroups:
        - !Ref SecurityGroup
      UserData:
        "Fn::Base64":
          !Sub |
            #cloud-config
            repo_update: true
            repo_upgrade: all

            packages:
            - parallel

            runcmd:
            - yum --enablerepo=epel install nload -y
            - ntpstat
            - /opt/aws/bin/cfn-init --configsets efs_add_storage --verbose --stack ${AWS::StackName} --resource LaunchConfiguration --region ${AWS::Region}
            - /tmp/efs-add-storage.sh ${ElasticFileSystem} throughput_data ${Growth}
            - /opt/aws/bin/cfn-signal -e $? --stack ${AWS::StackName} --resource AutoScalingGroup --region ${AWS::Region}