fix(globalaccelerator-endpoints): add preserveClientIp option for net…

…work loadbalancer

### Issue # (if applicable)

### Reason for this change

preserveClientIp was missing for GlobalAccelerator Endpoints when using a network loadbalancer.

### Description of changes

* add missing network load balancer endpoint prop.

### Description of how you validated changes

Added integration tests.

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

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

packages/aws-cdk-lib/aws-globalaccelerator-endpoints/lib/nlb.ts

@@ -14,6 +14,19 @@ export interface NetworkLoadBalancerEndpointProps {
    * @default 128
    */
   readonly weight?: number;
+
+  /**
+   * Forward the client IP address in an `X-Forwarded-For` header
+   *
+   * GlobalAccelerator will create Network Interfaces in your VPC in order
+   * to preserve the client IP address.
+   *
+   * Client IP address preservation is supported only in specific AWS Regions.
+   * See the GlobalAccelerator Developer Guide for a list.
+   *
+   * @default true if available
+   */
+  readonly preserveClientIp?: boolean;
 }
 
 /**
@@ -31,6 +44,7 @@ export class NetworkLoadBalancerEndpoint implements ga.IEndpoint {
     return {
       endpointId: this.loadBalancer.loadBalancerArn,
       weight: this.options.weight,
+      clientIpPreservationEnabled: this.options.preserveClientIp,
     } as ga.CfnEndpointGroup.EndpointConfigurationProperty;
   }
 }

packages/aws-cdk-lib/aws-globalaccelerator-endpoints/test/endpoints.test.ts

@@ -74,6 +74,7 @@ test('Network Load Balancer with all properties', () => {
     endpoints: [
       new endpoints.NetworkLoadBalancerEndpoint(nlb, {
         weight: 50,
+        preserveClientIp: true,
       }),
     ],
   });
@@ -84,6 +85,7 @@ test('Network Load Balancer with all properties', () => {
       {
         EndpointId: { Ref: 'NLB55158F82' },
         Weight: 50,
+        ClientIPPreservationEnabled: true,
       },
     ],
   });

packages/aws-cdk-lib/aws-globalaccelerator/README.md

@@ -116,6 +116,7 @@ listener.addEndpointGroup('Group', {
   endpoints: [
     new ga_endpoints.NetworkLoadBalancerEndpoint(nlb, {
       weight: 128,
+      preserveClientIp: true, 
     }),
   ],
 });