AWSTemplateFormatVersion: '2010-09-09'
Description: ''
Resources:
  SnsTopicMetricFilterCloudWatchAlarm:
    Type: 'AWS::SNS::Topic'
    Properties:
      Subscription:
        - Endpoint: email@example.com
          Protocol: email
      TopicName: alarm-action
  CloudWatchAlarm:
    Type: 'AWS::CloudWatch::Alarm'
    Properties:
      AlarmName: vpc_routetable_changes
      AlarmDescription: A CloudWatch Alarm that triggers when changes are made to a VPC's Route Table.
      MetricName: VpcRouteTableEventCount
      Namespace: CloudTrailMetrics
      Statistic: Sum
      Period: '300'
      EvaluationPeriods: '1'
      Threshold: '1'
      ComparisonOperator: GreaterThanOrEqualToThreshold
      AlarmActions:
        - Ref: SnsTopicMetricFilterCloudWatchAlarm
      TreatMissingData: notBreaching
  MetricFilterCloudWatchAlarm:
    Type: 'AWS::Logs::MetricFilter'
    Properties:
      LogGroupName: ''
      FilterPattern: '{ ($.eventName = AssociateRouteTable) || ($.eventName = CreateRoute) || ($.eventName = CreateRouteTable) || ($.eventName = DeleteRoute) || ($.eventName = DeleteRouteTable) || ($.eventName = ReplaceRoute) || ($.eventName = ReplaceRouteTableAssociation) || ($.eventName = DisassociateRouteTable) }'
      MetricTransformations:
        - MetricValue: '1'
          MetricNamespace: CloudTrailMetrics
          MetricName: VpcRouteTableEventCount
Parameters: {}
Metadata: {}
Conditions: {}