AWS WAF rule to only accept POST requests

Question

I am trying to create a WAF rule that only accepts POST requests. Via the UI this was straight forward, however trying to achieve the same with the CDK. I think I have most of it complete, but the Method is giving me problems. I would have thought it should be HttpMethod.Post but that does not work.

Here is what I have:

      Amazon.CDK.AWS.WAFv2.CfnWebACL cfnWebACL2 = new Amazon.CDK.AWS.WAFv2.CfnWebACL(this, "MyCfnWebACL", new Amazon.CDK.AWS.WAFv2.CfnWebACLProps {
        DefaultAction = new Amazon.CDK.AWS.WAFv2.CfnWebACL.DefaultActionProperty {
          Block = true
        },
        Name = "Allow_Post",
        Rules = new [] { new Amazon.CDK.AWS.WAFv2.CfnWebACL.RuleProperty {
            Name = "Allow_Post",
                  Priority = 1,
                  Statement = new Amazon.CDK.AWS.WAFv2.CfnWebACL.StatementProperty {
                    ByteMatchStatement = new Amazon.CDK.AWS.WAFv2.CfnWebACL.ByteMatchStatementProperty {
                      FieldToMatch = new Amazon.CDK.AWS.WAFv2.CfnWebACL.FieldToMatchProperty {
                        Method = HttpMethod.Post
                        },
                      PositionalConstraint = "EXACTLY",
                      SearchString = "POST",
                      TextTransformations = new [] { new Amazon.CDK.AWS.WAFv2.CfnWebACL.TextTransformationProperty {
                        Priority = 1,
                        Type = "NONE"
                      } },
                    }
                  },
                  VisibilityConfig = new Amazon.CDK.AWS.WAFv2.CfnWebACL.VisibilityConfigProperty {
                    CloudWatchMetricsEnabled = false,
                    MetricName = "metricName",
                    SampledRequestsEnabled = false

        }}},
        VisibilityConfig = new Amazon.CDK.AWS.WAFv2.CfnWebACL.VisibilityConfigProperty {
          CloudWatchMetricsEnabled = false,
          MetricName = "metricName",
          SampledRequestsEnabled = false
      },
        Scope = "REGIONAL",
      });

Answer 1

Finally got this working:

      Amazon.CDK.AWS.WAFv2.CfnWebACL cfnWebACL = new Amazon.CDK.AWS.WAFv2.CfnWebACL(this, "MyCfnWebACLw", new Amazon.CDK.AWS.WAFv2.CfnWebACLProps {
        DefaultAction = new Amazon.CDK.AWS.WAFv2.CfnWebACL.DefaultActionProperty {
          Block = new Amazon.CDK.AWS.WAFv2.CfnWebACL.BlockActionProperty {
            CustomResponse = new Amazon.CDK.AWS.WAFv2.CfnWebACL.CustomResponseProperty {
              ResponseCode = 403,
              }
          }
        },
        Scope = "REGIONAL",
        VisibilityConfig = new Amazon.CDK.AWS.WAFv2.CfnWebACL.VisibilityConfigProperty {
          MetricName = "test",
          SampledRequestsEnabled = false,
          CloudWatchMetricsEnabled = false
        },
        Rules = new [] { new Amazon.CDK.AWS.WAFv2.CfnWebACL.RuleProperty {
          Name = "myRule",
          Priority = 0,
          Statement = new Amazon.CDK.AWS.WAFv2.CfnWebACL.StatementProperty {
            ByteMatchStatement = new Amazon.CDK.AWS.WAFv2.CfnWebACL.ByteMatchStatementProperty {
              PositionalConstraint = "EXACTLY",
              SearchString = "POST",
              TextTransformations = new [] {new Amazon.CDK.AWS.WAFv2.CfnWebACL.TextTransformationProperty {
                Priority = 0,
                Type = "NONE"
              }},
              FieldToMatch = new Amazon.CDK.AWS.WAFv2.CfnWebACL.FieldToMatchProperty {
                Method = new Dictionary<string, object> {{ "name", "Post" }}
              }
            }
          },
          VisibilityConfig = new Amazon.CDK.AWS.WAFv2.CfnWebACL.VisibilityConfigProperty {
            MetricName = "myMEtric",
            SampledRequestsEnabled = false,
            CloudWatchMetricsEnabled = false
          },
          Action = new Amazon.CDK.AWS.WAFv2.CfnWebACL.RuleActionProperty {
            Allow = new Amazon.CDK.AWS.WAFv2.CfnWebACL.AllowActionProperty {
              CustomRequestHandling = new Amazon.CDK.AWS.WAFv2.CfnWebACL.CustomRequestHandlingProperty {
                InsertHeaders = new [] { new Amazon.CDK.AWS.WAFv2.CfnWebACL.CustomHTTPHeaderProperty {
                  Name = "name",
                  Value = "value"
                } }
                }
              }
          }
        }}
      });