CloudFormation Storage tier stack

storage.yaml

# I recommend to encrypt your database to make sure your snapshots and logs are encrypted too.
# Automatic snapshots are stored by AWS itself, however manual snapshots will be stored in your S3 account.
# You don't want to accidentally open access to an unencrypted version of your data!
# It is also preferable not to use your default AWS master key if you ever need to transfer a snapshot to another
# AWS account later as you can't give cross-account access to your master key.
#
# Not that we only create one primary DB instance for now, no read replica.
KmsKey:
    Type: AWS::KMS::Key
    Properties:
        Description: !Sub KMS Key for our ${AWS::StackName} DB
        KeyPolicy:
            Id: !Ref AWS::StackName
            Version: "2012-10-17"
            Statement:
                -
                    Sid: "Allow administration of the key"
                    Effect: "Allow"
                    Action:
                        - kms:Create*
                        - kms:Describe*
                        - kms:Enable*
                        - kms:List*
                        - kms:Put*
                        - kms:Update*
                        - kms:Revoke*
                        - kms:Disable*
                        - kms:Get*
                        - kms:Delete*
                        - kms:ScheduleKeyDeletion
                        - kms:CancelKeyDeletion
                    Principal:
                        AWS: !Ref AWS::AccountId
                    Resource: '*'
                -
                    Sid: "Allow use of the key"
                    Effect: "Allow"
                    Principal:
                        AWS: !Ref AWS::AccountId
                    Action:
                        - "kms:Encrypt"
                        - "kms:Decrypt"
                        - "kms:ReEncrypt*"
                        - "kms:GenerateDataKey*"
                        - "kms:DescribeKey"
                    Resource: "*"

DatabaseSubnetGroup:
    Type: AWS::RDS::DBSubnetGroup
    Properties:
        DBSubnetGroupDescription: CloudFormation managed DB subnet group.
        SubnetIds: !Ref DatabaseSubnets

DatabaseCluster:
    Type: AWS::RDS::DBCluster
    Properties:
        Engine: aurora
        DatabaseName: !Ref DatabaseName
        MasterUsername: !Ref DatabaseUsername
        MasterUserPassword: !Ref DatabasePassword
        BackupRetentionPeriod: 7
        PreferredBackupWindow: 01:00-02:30
        PreferredMaintenanceWindow: mon:03:00-mon:04:00
        DBSubnetGroupName: !Ref DatabaseSubnetGroup
        KmsKeyId: !GetAtt KmsKey.Arn
        StorageEncrypted: true
        VpcSecurityGroupIds:
          - !Ref DatabaseSecurityGroup

DatabasePrimaryInstance:
    Type: AWS::RDS::DBInstance
    Properties:
        Engine: aurora
        DBClusterIdentifier: !Ref DatabaseCluster
        DBInstanceClass: !Ref DatabaseInstanceType
        DBSubnetGroupName: !Ref DatabaseSubnetGroup