# ###################################
##       Rule Specification        ##
#####################################
# 
# Rule Identifier:
#   rds_cluster_deletion_protection_enabled_check
# 
# Description:
#   This control checks whether your Amazon Relational Database Service (Amazon RDS) cluster has deletion protection activated.
# 
# Reports on:
#   AWS::RDS::DBCluster
# 
# Evaluates:
#   AWS CloudFormation, AWS CloudFormation hook
# 
# Rule Parameters:
#  None
# 
# Scenarios:
#   Scenario: 1
#     Given: The input document is an AWS CloudFormation or CloudFormation hook document
#       And: The input document does not contain any Amazon RDS DB cluster resources
#      Then: SKIP
#   Scenario: 2
#     Given: The input document is an AWS CloudFormation or CloudFormation hook document
#       And: The input document contains an Amazon RDS DB cluster resource
#       And: 'DeletionProtection' has not been specified
#      Then: FAIL
#   Scenario: 3
#     Given: The input document is an AWS CloudFormation or CloudFormation hook document
#       And: The input document contains an Amazon RDS DB cluster resource
#       And: 'DeletionProtection' has been specified
#       And: 'DeletionProtection' has been set to bool(false)
#      Then: FAIL
#   Scenario: 4
#     Given: The input document is an AWS CloudFormation or CloudFormation hook document
#       And: The input document contains an Amazon RDS DB cluster resource
#       And: 'DeletionProtection' has been specified
#       And: 'DeletionProtection' has been set to bool(true)
#      Then: PASS

#
# Constants
#
let RDS_DB_CLUSTER_TYPE = "AWS::RDS::DBCluster"
let INPUT_DOCUMENT = this

#
# Assignments
#
let db_clusters = Resources.*[ Type == %RDS_DB_CLUSTER_TYPE ]

#
# Primary Rules
#
rule rds_cluster_deletion_protection_enabled_check when is_cfn_template(%INPUT_DOCUMENT)
                                                        %db_clusters not empty {
    check(%db_clusters.Properties)
        <<
        [CT.RDS.PR.3]: Require an Amazon RDS cluster to have deletion protection configured
        [FIX]: Set the value of the 'DeletionProtection' parameter to true.
        >>
}

rule rds_cluster_deletion_protection_enabled_check when is_cfn_hook(%INPUT_DOCUMENT, %RDS_DB_CLUSTER_TYPE) {
    check(%INPUT_DOCUMENT.%RDS_DB_CLUSTER_TYPE.resourceProperties)
        <<
        [CT.RDS.PR.3]: Require an Amazon RDS cluster to have deletion protection configured
        [FIX]: Set the value of the 'DeletionProtection' parameter to true.
        >>
}

rule check(properties) {
    %properties {
        # Scenario 2
        DeletionProtection exists
        # Scenario 3 and 4
        DeletionProtection == true
    }
}

#
# Utility Rules
#
rule is_cfn_template(doc) {
    %doc {
        AWSTemplateFormatVersion exists  or
        Resources exists
    }
}

rule is_cfn_hook(doc, RESOURCE_TYPE) {
    %doc.%RESOURCE_TYPE.resourceProperties exists
}