feat(ecs-patterns): add option to create cname instead of alias record (

#10812)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

packages/@aws-cdk/aws-ecs-patterns/README.md

@@ -66,6 +66,8 @@ Fargate services use the default VPC Security Group unless one or more are provi
 
 By setting `redirectHTTP` to true, CDK will automatically create a listener on port 80 that redirects HTTP traffic to the HTTPS port.
 
+If you specify the option `recordType` you can decide if you want the construct to use CNAME or Route53-Aliases as record sets.
+
 Additionally, if more than one application target group are needed, instantiate one of the following:
 
 * `ApplicationMultipleTargetGroupsEc2Service`
@@ -153,6 +155,8 @@ The CDK will create a new Amazon ECS cluster if you specify a VPC and omit `clus
 
 If `cluster` and `vpc` are omitted, the CDK creates a new VPC with subnets in two Availability Zones and a cluster within this VPC.
 
+If you specify the option `recordType` you can decide if you want the construct to use CNAME or Route53-Aliases as record sets.
+
 Additionally, if more than one network target group is needed, instantiate one of the following:
 
 * NetworkMultipleTargetGroupsEc2Service

packages/@aws-cdk/aws-ecs-patterns/lib/base/application-load-balanced-service-base.ts

@@ -6,11 +6,29 @@ import {
   IApplicationLoadBalancer, ListenerCertificate, ListenerAction,
 } from '@aws-cdk/aws-elasticloadbalancingv2';
 import { IRole } from '@aws-cdk/aws-iam';
-import { ARecord, IHostedZone, RecordTarget } from '@aws-cdk/aws-route53';
+import { ARecord, IHostedZone, RecordTarget, CnameRecord } from '@aws-cdk/aws-route53';
 import { LoadBalancerTarget } from '@aws-cdk/aws-route53-targets';
 import * as cdk from '@aws-cdk/core';
 import { Construct } from 'constructs';
 
+/**
+ * Describes the type of DNS record the service should create
+ */
+export enum ApplicationLoadBalancedServiceRecordType {
+  /**
+   * Create Route53 A Alias record
+   */
+  ALIAS,
+  /**
+   * Create a CNAME record
+   */
+  CNAME,
+  /**
+   * Do not create any DNS records
+   */
+  NONE
+}
+
 /**
  * The properties for the base ApplicationLoadBalancedEc2Service or ApplicationLoadBalancedFargateService service.
  */
@@ -177,6 +195,14 @@ export interface ApplicationLoadBalancedServiceBaseProps {
    * @default false
    */
   readonly redirectHTTP?: boolean;
+
+  /**
+   * Specifies whether the Route53 record should be a CNAME, an A record using the Alias feature or no record at all.
+   * This is useful if you need to work with DNS systems that do not support alias records.
+   *
+   * @default ApplicationLoadBalancedServiceRecordType.ALIAS
+   */
+  readonly recordType?: ApplicationLoadBalancedServiceRecordType;
 }
 
 export interface ApplicationLoadBalancedTaskImageOptions {
@@ -390,13 +416,27 @@ export abstract class ApplicationLoadBalancedServiceBase extends cdk.Construct {
         throw new Error('A Route53 hosted domain zone name is required to configure the specified domain name');
       }
 
-      const record = new ARecord(this, 'DNS', {
-        zone: props.domainZone,
-        recordName: props.domainName,
-        target: RecordTarget.fromAlias(new LoadBalancerTarget(loadBalancer)),
-      });
-
-      domainName = record.domainName;
+      switch (props.recordType ?? ApplicationLoadBalancedServiceRecordType.ALIAS) {
+        case ApplicationLoadBalancedServiceRecordType.ALIAS:
+          let aliasRecord = new ARecord(this, 'DNS', {
+            zone: props.domainZone,
+            recordName: props.domainName,
+            target: RecordTarget.fromAlias(new LoadBalancerTarget(loadBalancer)),
+          });
+          domainName = aliasRecord.domainName;
+          break;
+        case ApplicationLoadBalancedServiceRecordType.CNAME:
+          let cnameRecord = new CnameRecord(this, 'DNS', {
+            zone: props.domainZone,
+            recordName: props.domainName,
+            domainName: loadBalancer.loadBalancerDnsName,
+          });
+          domainName = cnameRecord.domainName;
+          break;
+        case ApplicationLoadBalancedServiceRecordType.NONE:
+          // Do not create a DNS record
+          break;
+      }
     }
 
     if (loadBalancer instanceof ApplicationLoadBalancer) {

packages/@aws-cdk/aws-ecs-patterns/lib/base/network-load-balanced-service-base.ts

@@ -2,11 +2,29 @@ import { IVpc } from '@aws-cdk/aws-ec2';
 import { AwsLogDriver, BaseService, CloudMapOptions, Cluster, ContainerImage, ICluster, LogDriver, PropagatedTagSource, Secret } from '@aws-cdk/aws-ecs';
 import { INetworkLoadBalancer, NetworkListener, NetworkLoadBalancer, NetworkTargetGroup } from '@aws-cdk/aws-elasticloadbalancingv2';
 import { IRole } from '@aws-cdk/aws-iam';
-import { ARecord, IHostedZone, RecordTarget } from '@aws-cdk/aws-route53';
+import { ARecord, CnameRecord, IHostedZone, RecordTarget } from '@aws-cdk/aws-route53';
 import { LoadBalancerTarget } from '@aws-cdk/aws-route53-targets';
 import * as cdk from '@aws-cdk/core';
 import { Construct } from 'constructs';
 
+/**
+ * Describes the type of DNS record the service should create
+ */
+export enum NetworkLoadBalancedServiceRecordType {
+  /**
+   * Create Route53 A Alias record
+   */
+  ALIAS,
+  /**
+   * Create a CNAME record
+   */
+  CNAME,
+  /**
+   * Do not create any DNS records
+   */
+  NONE
+}
+
 /**
  * The properties for the base NetworkLoadBalancedEc2Service or NetworkLoadBalancedFargateService service.
  */
@@ -136,6 +154,14 @@ export interface NetworkLoadBalancedServiceBaseProps {
    * @default - AWS Cloud Map service discovery is not enabled.
    */
   readonly cloudMapOptions?: CloudMapOptions;
+
+  /**
+   * Specifies whether the Route53 record should be a CNAME, an A record using the Alias feature or no record at all.
+   * This is useful if you need to work with DNS systems that do not support alias records.
+   *
+   * @default NetworkLoadBalancedServiceRecordType.ALIAS
+   */
+  readonly recordType?: NetworkLoadBalancedServiceRecordType;
 }
 
 export interface NetworkLoadBalancedTaskImageOptions {
@@ -294,11 +320,25 @@ export abstract class NetworkLoadBalancedServiceBase extends cdk.Construct {
         throw new Error('A Route53 hosted domain zone name is required to configure the specified domain name');
       }
 
-      new ARecord(this, 'DNS', {
-        zone: props.domainZone,
-        recordName: props.domainName,
-        target: RecordTarget.fromAlias(new LoadBalancerTarget(loadBalancer)),
-      });
+      switch (props.recordType ?? NetworkLoadBalancedServiceRecordType.ALIAS) {
+        case NetworkLoadBalancedServiceRecordType.ALIAS:
+          new ARecord(this, 'DNS', {
+            zone: props.domainZone,
+            recordName: props.domainName,
+            target: RecordTarget.fromAlias(new LoadBalancerTarget(loadBalancer)),
+          });
+          break;
+        case NetworkLoadBalancedServiceRecordType.CNAME:
+          new CnameRecord(this, 'DNS', {
+            zone: props.domainZone,
+            recordName: props.domainName,
+            domainName: loadBalancer.loadBalancerDnsName,
+          });
+          break;
+        case NetworkLoadBalancedServiceRecordType.NONE:
+          // Do not create a DNS record
+          break;
+      }
     }
 
     if (loadBalancer instanceof NetworkLoadBalancer) {

packages/@aws-cdk/aws-ecs-patterns/test/fargate/test.load-balanced-fargate-service.ts

@@ -424,6 +424,123 @@ export = {
     test.done();
   },
 
+  'setting ALB cname option correctly sets the recordset type'(test: Test) {
+    // GIVEN
+    const stack = new cdk.Stack();
+    const vpc = new ec2.Vpc(stack, 'VPC');
+    const cluster = new ecs.Cluster(stack, 'Cluster', { vpc });
+
+    // WHEN
+    new ecsPatterns.ApplicationLoadBalancedFargateService(stack, 'FargateAlbService', {
+      cluster,
+      protocol: ApplicationProtocol.HTTPS,
+      domainName: 'test.domain.com',
+      domainZone: route53.HostedZone.fromHostedZoneAttributes(stack, 'HostedZone', {
+        hostedZoneId: 'fakeId',
+        zoneName: 'domain.com.',
+      }),
+      recordType: ecsPatterns.ApplicationLoadBalancedServiceRecordType.CNAME,
+      taskImageOptions: {
+        containerPort: 2015,
+        image: ecs.ContainerImage.fromRegistry('abiosoft/caddy'),
+      },
+    });
+
+    // THEN
+    expect(stack).to(haveResourceLike('AWS::Route53::RecordSet', {
+      Name: 'test.domain.com.',
+      Type: 'CNAME',
+    }));
+
+    test.done();
+  },
+
+  'setting ALB record type to NONE correctly omits the recordset'(test: Test) {
+    // GIVEN
+    const stack = new cdk.Stack();
+    const vpc = new ec2.Vpc(stack, 'VPC');
+    const cluster = new ecs.Cluster(stack, 'Cluster', { vpc });
+
+    // WHEN
+    new ecsPatterns.ApplicationLoadBalancedFargateService(stack, 'FargateAlbService', {
+      cluster,
+      protocol: ApplicationProtocol.HTTPS,
+      domainName: 'test.domain.com',
+      domainZone: route53.HostedZone.fromHostedZoneAttributes(stack, 'HostedZone', {
+        hostedZoneId: 'fakeId',
+        zoneName: 'domain.com.',
+      }),
+      recordType: ecsPatterns.ApplicationLoadBalancedServiceRecordType.NONE,
+      taskImageOptions: {
+        containerPort: 2015,
+        image: ecs.ContainerImage.fromRegistry('abiosoft/caddy'),
+      },
+    });
+
+    // THEN
+    expect(stack).notTo(haveResource('AWS::Route53::RecordSet'));
+
+    test.done();
+  },
+
+
+  'setting NLB cname option correctly sets the recordset type'(test: Test) {
+    // GIVEN
+    const stack = new cdk.Stack();
+    const vpc = new ec2.Vpc(stack, 'VPC');
+    const cluster = new ecs.Cluster(stack, 'Cluster', { vpc });
+
+    // WHEN
+    new ecsPatterns.NetworkLoadBalancedFargateService(stack, 'FargateNlbService', {
+      cluster,
+      domainName: 'test.domain.com',
+      domainZone: route53.HostedZone.fromHostedZoneAttributes(stack, 'HostedZone', {
+        hostedZoneId: 'fakeId',
+        zoneName: 'domain.com.',
+      }),
+      recordType: ecsPatterns.NetworkLoadBalancedServiceRecordType.CNAME,
+      taskImageOptions: {
+        containerPort: 2015,
+        image: ecs.ContainerImage.fromRegistry('abiosoft/caddy'),
+      },
+    });
+
+    // THEN
+    expect(stack).to(haveResourceLike('AWS::Route53::RecordSet', {
+      Name: 'test.domain.com.',
+      Type: 'CNAME',
+    }));
+
+    test.done();
+  },
+
+  'setting NLB record type to NONE correctly omits the recordset'(test: Test) {
+    // GIVEN
+    const stack = new cdk.Stack();
+    const vpc = new ec2.Vpc(stack, 'VPC');
+    const cluster = new ecs.Cluster(stack, 'Cluster', { vpc });
+
+    // WHEN
+    new ecsPatterns.NetworkLoadBalancedFargateService(stack, 'FargateNlbService', {
+      cluster,
+      domainName: 'test.domain.com',
+      domainZone: route53.HostedZone.fromHostedZoneAttributes(stack, 'HostedZone', {
+        hostedZoneId: 'fakeId',
+        zoneName: 'domain.com.',
+      }),
+      recordType: ecsPatterns.NetworkLoadBalancedServiceRecordType.NONE,
+      taskImageOptions: {
+        containerPort: 2015,
+        image: ecs.ContainerImage.fromRegistry('abiosoft/caddy'),
+      },
+    });
+
+    // THEN
+    expect(stack).notTo(haveResource('AWS::Route53::RecordSet'));
+
+    test.done();
+  },
+
   'setting ALB HTTP protocol to create the listener on 80'(test: Test) {
     // GIVEN
     const stack = new cdk.Stack();