Using C# CDK create a WAF CfnWebACL that uses a AWS managed ruleset.

[adam-clauss]

I am attempting to create a web acl (WAFv2). It includes some manual/custom rule definitions that work/create fine. However, when I tried to add an AWS managed rule to the mix, I started getting errors upon deployment.

            CfnWebACL.RuleProperty coreManagedRule = new()
            {
                Name = "AWS-AWSManagedRulesCommonRuleSet",
                Priority = rulePriority++,
                Statement = new CfnWebACL.StatementProperty
                {
                    ManagedRuleGroupStatement = new CfnWebACL.ManagedRuleGroupStatementProperty
                    {
                        VendorName = "AWS",
                        Name = "AWSManagedRulesCommonRuleSet",
                    }
                },
                Action = new CfnWebACL.RuleActionProperty { Block = new CfnWebACL.BlockActionProperty() },
                OverrideAction = new CfnWebACL.OverrideActionProperty
                {
                    None = new object()
                },
                VisibilityConfig = new CfnWebACL.VisibilityConfigProperty
                {
                    SampledRequestsEnabled = true,
                    CloudWatchMetricsEnabled = true,
                    MetricName = "AWSManagedRulesCommonRuleSet"
                }
            };

If I comment out the OverrideAction, I get:
Resource handler returned message: "Error reason: A reference in your rule statement is not valid., field: RULE, parameter: Statement (Service: Wafv2, Status Code: 400, Request ID: 434fa12f-e04b-46e6-8032-c73ff13c9e5a)" (RequestToken: 37d7ad12-84da-42d0-20bc-05f4c90b6c12, HandlerErrorCode: InvalidRequest)

If I have that OverideAction, I get an error during synthesis:
Unhandled exception. System.ArgumentException: Could not infer JSII type for .NET type 'Object' (Parameter 'type')

I saw some references online and from ChatGPT that None is supposed to be initialized to a "NoneActionProperty":

OverrideAction = new CfnWebACL.OverrideActionProperty
{
    None = new CfnWebACL.NoneActionProperty()
},

However, no such type seems to exist currently. It would make sense though, as there IS a CountActionProperty for the Count version (instead of none).

OverrideAction = new CfnWebACL.OverrideActionProperty
{
    Count = new CfnWebACL.CountActionProperty()
},

This is the JSON for the equivalent rule I am trying to create when created through the AWS console itself:

{
  "Name": "AWS-AWSManagedRulesCommonRuleSet",
  "Priority": 2,
  "Statement": {
    "ManagedRuleGroupStatement": {
      "VendorName": "AWS",
      "Name": "AWSManagedRulesCommonRuleSet"
    }
  },
  "OverrideAction": {
    "None": {}
  },
  "VisibilityConfig": {
    "SampledRequestsEnabled": true,
    "CloudWatchMetricsEnabled": true,
    "MetricName": "AWS-AWSManagedRulesCommonRuleSet"
  }
}

Am I missing something?