Amazon DynamoDB template snippets

Application Auto Scaling with an Amazon DynamoDB table

This example sets up Application Auto Scaling for a AWS::DynamoDB::Table resource. The template defines a TargetTrackingScaling scaling policy that scales up the WriteCapacityUnits throughput for the table.

{
    "Resources": {
        "DDBTable": {
            "Type": "AWS::DynamoDB::Table",
            "Properties": {
                "AttributeDefinitions": [
                    {
                        "AttributeName": "ArtistId",
                        "AttributeType": "S"
                    },
                    {
                        "AttributeName": "Concert",
                        "AttributeType": "S"
                    },
                    {
                        "AttributeName": "TicketSales",
                        "AttributeType": "S"
                    }
                ],
                "KeySchema": [
                    {
                        "AttributeName": "ArtistId",
                        "KeyType": "HASH"
                    },
                    {
                        "AttributeName": "Concert",
                        "KeyType": "RANGE"
                    }
                ],
                "GlobalSecondaryIndexes": [
                    {
                        "IndexName": "GSI",
                        "KeySchema": [
                            {
                                "AttributeName": "TicketSales",
                                "KeyType": "HASH"
                            }
                        ],
                        "Projection": {
                            "ProjectionType": "KEYS_ONLY"
                        },
                        "ProvisionedThroughput": {
                            "ReadCapacityUnits": 5,
                            "WriteCapacityUnits": 5
                        }
                    }
                ],
                "ProvisionedThroughput": {
                    "ReadCapacityUnits": 5,
                    "WriteCapacityUnits": 5
                }
            }
        },
        "WriteCapacityScalableTarget": {
            "Type": "AWS::ApplicationAutoScaling::ScalableTarget",
            "Properties": {
                "MaxCapacity": 15,
                "MinCapacity": 5,
                "ResourceId": {
                    "Fn::Join": [
                        "/",
                        [
                            "table",
                            {
                                "Ref": "DDBTable"
                            }
                        ]
                    ]
                },
                "RoleARN": {
                    "Fn::GetAtt": [
                        "ScalingRole",
                        "Arn"
                    ]
                },
                "ScalableDimension": "dynamodb:table:WriteCapacityUnits",
                "ServiceNamespace": "dynamodb"
            }
        },
        "ScalingRole": {
            "Type": "AWS::IAM::Role",
            "Properties": {
                "AssumeRolePolicyDocument": {
                    "Version": "2012-10-17",
                    "Statement": [
                        {
                            "Effect": "Allow",
                            "Principal": {
                                "Service": [
                                    "application-autoscaling.amazonaws.com"
                                ]
                            },
                            "Action": [
                                "sts:AssumeRole"
                            ]
                        }
                    ]
                },
                "Path": "/",
                "Policies": [
                    {
                        "PolicyName": "root",
                        "PolicyDocument": {
                            "Version": "2012-10-17",
                            "Statement": [
                                {
                                    "Effect": "Allow",
                                    "Action": [
                                        "dynamodb:DescribeTable",
                                        "dynamodb:UpdateTable",
                                        "cloudwatch:PutMetricAlarm",
                                        "cloudwatch:DescribeAlarms",
                                        "cloudwatch:GetMetricStatistics",
                                        "cloudwatch:SetAlarmState",
                                        "cloudwatch:DeleteAlarms"
                                    ],
                                    "Resource": "*"
                                }
                            ]
                        }
                    }
                ]
            }
        },
        "WriteScalingPolicy": {
            "Type": "AWS::ApplicationAutoScaling::ScalingPolicy",
            "Properties": {
                "PolicyName": "WriteAutoScalingPolicy",
                "PolicyType": "TargetTrackingScaling",
                "ScalingTargetId": {
                    "Ref": "WriteCapacityScalableTarget"
                },
                "TargetTrackingScalingPolicyConfiguration": {
                    "TargetValue": 50,
                    "ScaleInCooldown": 60,
                    "ScaleOutCooldown": 60,
                    "PredefinedMetricSpecification": {
                        "PredefinedMetricType": "DynamoDBWriteCapacityUtilization"
                    }
                }
            }
        }
    }
}

Resources:
  DDBTable:
    Type: AWS::DynamoDB::Table
    Properties:
      AttributeDefinitions:
        -
          AttributeName: "ArtistId"
          AttributeType: "S"
        -
          AttributeName: "Concert"
          AttributeType: "S"
        -
          AttributeName: "TicketSales"
          AttributeType: "S"
      KeySchema:
        -
          AttributeName: "ArtistId"
          KeyType: "HASH"
        -
          AttributeName: "Concert"
          KeyType: "RANGE"
      GlobalSecondaryIndexes:
        -
          IndexName: "GSI"
          KeySchema:
            -
              AttributeName: "TicketSales"
              KeyType: "HASH"
          Projection:
            ProjectionType: "KEYS_ONLY"
          ProvisionedThroughput:
            ReadCapacityUnits: 5
            WriteCapacityUnits: 5
      ProvisionedThroughput:
        ReadCapacityUnits: 5
        WriteCapacityUnits: 5
  WriteCapacityScalableTarget:
    Type: AWS::ApplicationAutoScaling::ScalableTarget
    Properties:
      MaxCapacity: 15
      MinCapacity: 5
      ResourceId: !Join
        - /
        - - table
          - !Ref DDBTable
      RoleARN: !GetAtt ScalingRole.Arn
      ScalableDimension: dynamodb:table:WriteCapacityUnits
      ServiceNamespace: dynamodb
  ScalingRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: "2012-10-17"
        Statement:
          -
            Effect: "Allow"
            Principal:
              Service:
                - application-autoscaling.amazonaws.com
            Action:
              - "sts:AssumeRole"
      Path: "/"
      Policies:
        -
          PolicyName: "root"
          PolicyDocument:
            Version: "2012-10-17"
            Statement:
              -
                Effect: "Allow"
                Action:
                  - "dynamodb:DescribeTable"
                  - "dynamodb:UpdateTable"
                  - "cloudwatch:PutMetricAlarm"
                  - "cloudwatch:DescribeAlarms"
                  - "cloudwatch:GetMetricStatistics"
                  - "cloudwatch:SetAlarmState"
                  - "cloudwatch:DeleteAlarms"
                Resource: "*"
  WriteScalingPolicy:
    Type: AWS::ApplicationAutoScaling::ScalingPolicy
    Properties:
      PolicyName: WriteAutoScalingPolicy
      PolicyType: TargetTrackingScaling
      ScalingTargetId: !Ref WriteCapacityScalableTarget
      TargetTrackingScalingPolicyConfiguration:
        TargetValue: 50.0
        ScaleInCooldown: 60
        ScaleOutCooldown: 60
        PredefinedMetricSpecification:
          PredefinedMetricType: DynamoDBWriteCapacityUtilization

See also

For more information, see the blog post How to use Amazon CloudFormation to configure auto scaling for Amazon DynamoDB tables and indexes on the Amazon Database Blog.

For more information about DynamoDB resources, see AWS::DynamoDB::Table.