fix(aws-cloudfront): Allow to disable IPv6 on cloudfront distribution (#1244)

Fixes #1243

Author: jlamande

packages/@aws-cdk/aws-cloudfront/lib/web_distribution.ts

@@ -532,7 +532,7 @@ export class CloudFrontWebDistribution extends cdk.Construct implements route53.
       defaultRootObject: props.defaultRootObject !== undefined ? props.defaultRootObject : "index.html",
       httpVersion: props.httpVersion || HttpVersion.HTTP2,
       priceClass: props.priceClass || PriceClass.PriceClass100,
-      ipv6Enabled: props.enableIpV6 || true,
+      ipv6Enabled: (props.enableIpV6 !== undefined) ? props.enableIpV6 : true,
       // tslint:disable-next-line:max-line-length
       customErrorResponses: props.errorConfigurations, // TODO: validation : https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-cloudfront-distribution-customerrorresponse.html#cfn-cloudfront-distribution-customerrorresponse-errorcachingminttl
       webAclId: props.webACLId,

packages/@aws-cdk/aws-cloudfront/test/integ.cloudfront-ipv6-disabled.expected.json

@@ -0,0 +1,53 @@
+{
+  "Resources": {
+    "Bucket83908E77": {
+      "Type": "AWS::S3::Bucket"
+    },
+    "MyDistributionCFDistributionDE147309": {
+      "Type": "AWS::CloudFront::Distribution",
+      "Properties": {
+        "DistributionConfig": {
+          "CacheBehaviors": [],
+          "DefaultCacheBehavior": {
+            "AllowedMethods": [
+              "GET",
+              "HEAD"
+            ],
+            "CachedMethods": [
+              "GET",
+              "HEAD"
+            ],
+            "ForwardedValues": {
+              "Cookies": {
+                "Forward": "none"
+              },
+              "QueryString": false
+            },
+            "TargetOriginId": "origin1",
+            "ViewerProtocolPolicy": "redirect-to-https"
+          },
+          "DefaultRootObject": "index.html",
+          "Enabled": true,
+          "HttpVersion": "http2",
+          "IPV6Enabled": false,
+          "Origins": [
+            {
+              "DomainName": {
+                "Fn::GetAtt": [
+                  "Bucket83908E77",
+                  "DomainName"
+                ]
+              },
+              "Id": "origin1",
+              "S3OriginConfig": {}
+            }
+          ],
+          "PriceClass": "PriceClass_100",
+          "ViewerCertificate": {
+            "CloudFrontDefaultCertificate": true
+          }
+        }
+      }
+    }
+  }
+}

packages/@aws-cdk/aws-cloudfront/test/integ.cloudfront-ipv6-disabled.ts

@@ -0,0 +1,24 @@
+
+import s3 = require('@aws-cdk/aws-s3');
+import cdk = require('@aws-cdk/cdk');
+import cloudfront = require('../lib');
+
+const app = new cdk.App();
+
+const stack = new cdk.Stack(app, 'aws-cdk-cloudfront');
+
+const sourceBucket = new s3.Bucket(stack, 'Bucket');
+
+new cloudfront.CloudFrontWebDistribution(stack, 'MyDistribution', {
+  originConfigs: [
+    {
+      s3OriginSource: {
+        s3BucketSource: sourceBucket
+      },
+      behaviors : [ {isDefaultBehavior: true}]
+    }
+  ],
+  enableIpV6: false
+ });
+
+app.run();