fix(route53): support zone roots as record names (#2705)

Author: hoegertn

packages/@aws-cdk/aws-route53/lib/records/_util.ts

@@ -11,7 +11,7 @@ import { IHostedZone } from '../hosted-zone-ref';
  *
  * @returns <ul>
  *        <li>If +providedName+ ends with a +.+, use it as-is</li>
- *        <li>If +providedName+ ends with +zoneName+, append a trailing +.+</li>
+ *        <li>If +providedName+ ends with or equals +zoneName+, append a trailing +.+</li>
  *        <li>Otherwise, append +.+, +zoneName+ and a trailing +.+</li>
  *      </ul>
  */
@@ -21,7 +21,7 @@ export function determineFullyQualifiedDomainName(providedName: string, hostedZo
   }
 
   const suffix = `.${hostedZone.zoneName}`;
-  if (providedName.endsWith(suffix)) {
+  if (providedName.endsWith(suffix) || providedName === hostedZone.zoneName) {
     return `${providedName}.`;
   }
 

packages/@aws-cdk/aws-route53/test/test.alias-record.ts

@@ -38,6 +38,42 @@ export = {
       }
     }));
 
+    test.done();
+  },
+  'test alias record on zone root'(test: Test) {
+    // GIVEN
+    const stack = new Stack();
+    const zone = new PublicHostedZone(stack, 'HostedZone', { zoneName: 'test.public' });
+
+    const target: IAliasRecordTarget = {
+      bind: () => {
+        return {
+          hostedZoneId: 'Z2P70J7EXAMPLE',
+          dnsName: 'foo.example.com'
+        };
+      }
+    };
+
+    // WHEN
+    new AliasRecord(zone, 'Alias', {
+      zone,
+      recordName: 'test.public',
+      target
+    });
+
+    // THEN - stack contains a record set
+    expect(stack).to(haveResource('AWS::Route53::RecordSet', {
+      Name: 'test.public.',
+      HostedZoneId: {
+        Ref: 'HostedZoneDB99F866'
+      },
+      Type: 'A',
+      AliasTarget: {
+        HostedZoneId: 'Z2P70J7EXAMPLE',
+        DNSName: 'foo.example.com',
+      }
+    }));
+
     test.done();
   }
 };