feat(ec2): make netmaskLength optional in IPAM allocation interfaces and update documentation

Author: betchi207

packages/@aws-cdk-testing/framework-integ/test/aws-ec2/test/integ.subnet-ipam.lit.ts

@@ -1,62 +1,62 @@
 import { SubnetIpamTest, SubnetIpamIntegTest } from './integ.subnet-ipam';
 
-// 既存テストスタックの説明
+// Description of the existing test stack
 const literalOutput = `
-# サブネットの機能とIPv6のサポート
+# Subnet Features and IPv6 Support
 
-このテストは、AWS CDKでのサブネットの基本機能とIPv6サポートのテスト例です。
-また、将来的な機能として実装予定のIPAM（IP Address Manager）機能についても説明しています。
+This test demonstrates basic subnet functionality and IPv6 support in AWS CDK.
+It also explains the IPAM (IP Address Manager) features that will be implemented.
 
-## テスト内容
+## Test Contents
 
-1. **基本的なサブネットの作成**
-   - VPC内に標準的なIPv4サブネットを作成
-   - 固定のCIDRブロックを使用
+1. **Basic Subnet Creation**
+   - Creating a standard IPv4 subnet within a VPC
+   - Using fixed CIDR blocks
 
-2. **IPv6サポートの有効化**
-   - 2つ目のサブネットでIPv6アドレスの自動割り当てを有効化
-   - デュアルスタック（IPv4/IPv6）構成の検証
+2. **IPv6 Support Enablement**
+   - Enabling automatic IPv6 address assignment on a second subnet
+   - Validating dual-stack (IPv4/IPv6) configuration
 
-## 将来の機能: IPAM (IP Address Manager) 統合
+## Future Feature: IPAM (IP Address Manager) Integration
 
-AWS IP Address Manager (IPAM) の統合により、以下の機能が利用可能になる予定です:
+AWS IP Address Manager (IPAM) integration will enable the following features:
 
-- IPv4およびIPv6アドレス空間を一元管理
-- IPAMプールからCIDRを動的に割り当て
-- 使用中のCIDRブロックの重複を防止
-- IPアドレスの割り当て履歴を追跡
+- Centralized management of IPv4 and IPv6 address space
+- Dynamic allocation of CIDRs from IPAM pools
+- Prevention of CIDR block overlaps in use
+- Tracking of IP address allocation history
 
-IPAM機能の例（将来のリリースで実装予定）:
+IPAM feature examples (to be implemented in future releases):
 
 \`\`\`typescript
-// IPv4 IPAM割り当てを使用したサブネット
+// Subnet using IPv4 IPAM allocation
 const subnet = new ec2.Subnet(stack, 'Subnet', {
   vpcId: vpc.vpcId,
   availabilityZone: vpc.availabilityZones[0],
   ipv4IpamAllocation: {
-    ipamPoolId: 'ipam-pool-id', // 実際のIPAMプールID
-    netmaskLength: 24,
+    ipamPoolId: 'ipam-pool-id', // Actual IPAM pool ID
+    netmaskLength: 24, // Optional: If not specified, the default netmask length from the IPAM pool will be used
   },
 });
 
-// IPv6 IPAM割り当てを使用したサブネット
+// Subnet using IPv6 IPAM allocation
 const subnetIpv6 = new ec2.Subnet(stack, 'SubnetIpv6', {
   vpcId: vpc.vpcId,
   availabilityZone: vpc.availabilityZones[1],
   cidrBlock: '10.0.1.0/24',
   assignIpv6AddressOnCreation: true,
   ipv6IpamAllocation: {
-    ipamPoolId: 'ipam-pool-id', // 実際のIPAMプールID
-    netmaskLength: 64,
+    ipamPoolId: 'ipam-pool-id', // Actual IPAM pool ID
+    // netmaskLength is optional
   },
 });
 \`\`\`
 
-## テスト実行方法
+## Test Execution Method
 
-このテストは合成のみを行い、実際のデプロイは実行しません。
-IPAM機能を実際にテストするには、AWS組織内で設定されたIPAMプールが必要です。
+This test only performs synthesis and does not actually deploy.
+To actually test IPAM features, you need an IPAM pool configured within your AWS organization.
 `;
 
-// スタックをリエクスポート
+// Re-export stacks
 export = { SubnetIpamTest, SubnetIpamIntegTest, literalOutput };

packages/@aws-cdk-testing/framework-integ/test/aws-ec2/test/integ.subnet-ipam.ts

@@ -6,30 +6,26 @@ const app = new cdk.App();
 
 /**
  * Test stack - Examples of using IPAM features with Subnets
- * テストスタック - サブネットでIPAM機能を使用する例
  */
 export class SubnetIpamTestStack extends cdk.Stack {
   constructor(scope: cdk.App, id: string, props?: cdk.StackProps) {
     super(scope, id, props);
 
     // Create a VPC first
-    // まず、VPCを作成
     const vpc = new ec2.Vpc(this, 'TestVpc', {
       maxAzs: 2,
       natGateways: 0,
       subnetConfiguration: [],
     });
 
     // Basic IPv4 subnet with CIDR block
-    // 基本的なIPv4 CIDRブロックを使用したサブネット
     const subnetWithIpv4 = new ec2.Subnet(this, 'SubnetWithIpv4', {
       vpcId: vpc.vpcId,
       availabilityZone: vpc.availabilityZones[0],
       cidrBlock: '10.0.0.0/24',
     });
 
     // IPv4 subnet with public IP mapping enabled
-    // パブリックIPマッピングを有効にしたIPv4サブネット
     const subnetWithPublicIp = new ec2.Subnet(this, 'SubnetWithPublicIp', {
       vpcId: vpc.vpcId,
       availabilityZone: vpc.availabilityZones[0],
@@ -38,7 +34,6 @@ export class SubnetIpamTestStack extends cdk.Stack {
     });
 
     // IPv4 subnet with IPv6 CIDR block
-    // IPv6 CIDRブロックを追加したIPv4サブネット
     const subnetWithIpv6 = new ec2.Subnet(this, 'SubnetWithIpv6', {
       vpcId: vpc.vpcId,
       availabilityZone: vpc.availabilityZones[1],
@@ -48,9 +43,7 @@ export class SubnetIpamTestStack extends cdk.Stack {
     });
 
     // Test IPAM allocation using CloudFormation intrinsic functions
-    // CloudFormation組み込み関数を使用してIPAM割り当てをテスト
     // IPv4 IPAM allocation - using token to simulate an IPAM pool ID
-    // IPv4 IPAM割り当て - トークンを使用してIPAMプールIDをシミュレート
     const ipamPoolIdIpv4 = new cdk.CfnParameter(this, 'IpamPoolIdIpv4', {
       type: 'String',
       default: 'ipam-pool-0example0123456789',
@@ -67,7 +60,6 @@ export class SubnetIpamTestStack extends cdk.Stack {
     });
 
     // IPv6 IPAM allocation - using token to simulate an IPAM pool ID
-    // IPv6 IPAM割り当て - トークンを使用してIPAMプールIDをシミュレート
     const ipamPoolIdIpv6 = new cdk.CfnParameter(this, 'IpamPoolIdIpv6', {
       type: 'String',
       default: 'ipam-pool-0example9876543210',
@@ -86,7 +78,6 @@ export class SubnetIpamTestStack extends cdk.Stack {
     });
 
     // Combined IPv4 and IPv6 IPAM allocations
-    // IPv4とIPv6の両方のIPAM割り当て
     const subnetWithBothIpamAllocations = new ec2.Subnet(this, 'SubnetWithBothIpamAllocations', {
       vpcId: vpc.vpcId,
       availabilityZone: vpc.availabilityZones[0],
@@ -101,8 +92,22 @@ export class SubnetIpamTestStack extends cdk.Stack {
       assignIpv6AddressOnCreation: true,
     });
 
+    // IPv4 and IPv6 IPAM allocations without netmaskLength
+    const subnetWithIpamAllocationsWithoutNetmask = new ec2.Subnet(this, 'SubnetWithIpamAllocationsWithoutNetmask', {
+      vpcId: vpc.vpcId,
+      availabilityZone: vpc.availabilityZones[1],
+      ipv4IpamAllocation: {
+        ipamPoolId: ipamPoolIdIpv4.valueAsString,
+        // netmaskLength is optional and will use the IPAM pool's default
+      },
+      ipv6IpamAllocation: {
+        ipamPoolId: ipamPoolIdIpv6.valueAsString,
+        // netmaskLength is optional and will use the IPAM pool's default
+      },
+      assignIpv6AddressOnCreation: true,
+    });
+
     // Output the subnet IDs for reference
-    // 参照用にサブネットIDを出力
     // Basic IPv4 subnet
     new cdk.CfnOutput(this, 'IPv4SubnetId', {
       value: subnetWithIpv4.subnetId,
@@ -138,19 +143,22 @@ export class SubnetIpamTestStack extends cdk.Stack {
       value: subnetWithBothIpamAllocations.subnetId,
       description: 'The subnet ID of the subnet with both IPv4 and IPv6 IPAM allocations',
     });
+
+    // IPv4 and IPv6 IPAM allocations without netmaskLength subnet
+    new cdk.CfnOutput(this, 'IpamAllocationsWithoutNetmaskSubnetId', {
+      value: subnetWithIpamAllocationsWithoutNetmask.subnetId,
+      description: 'The subnet ID of the subnet with IPv4 and IPv6 IPAM allocations without netmaskLength',
+    });
   }
 }
 
 // Create an instance of the test stack
-// テストスタックのインスタンスを作成
 export const SubnetIpamTest = new SubnetIpamTestStack(app, 'SubnetIpamTest');
 
 // Create an IntegTest (for CDK Integration Test framework)
-// IntegTestを作成（CDKのIntegration Testフレームワーク用）
 export const SubnetIpamIntegTest = new IntegTest(app, 'SubnetIpamIntegTest', {
   testCases: [SubnetIpamTest],
   // This test only performs synthesis and does not actually deploy
-  // このテストは合成のみを行い、実際のデプロイは実行しない
   cdkCommandOptions: {
     deploy: {
       enabled: false,

packages/aws-cdk-lib/aws-ec2/README.md

@@ -2621,7 +2621,7 @@ new ec2.Subnet(this, 'Subnet', {
   availabilityZone: 'us-east-1a',
   ipv4IpamAllocation: {
     ipamPoolId: 'ipam-pool-12345',
-    netmaskLength: 24,
+    netmaskLength: 24, // Optional: if not specified, uses the default netmask length from the IPAM pool
   },
 });
 ```
@@ -2636,7 +2636,7 @@ new ec2.Subnet(this, 'Subnet', {
   cidrBlock: '10.0.0.0/24', // IPv4 CIDR is required
   ipv6IpamAllocation: {
     ipamPoolId: 'ipam-pool-67890',
-    netmaskLength: 64,
+    netmaskLength: 64, // Optional: if not specified, uses the default netmask length from the IPAM pool
   },
   assignIpv6AddressOnCreation: true,
 });
@@ -2651,11 +2651,11 @@ new ec2.Subnet(this, 'Subnet', {
   availabilityZone: 'us-east-1a',
   ipv4IpamAllocation: {
     ipamPoolId: 'ipam-pool-12345',
-    netmaskLength: 24,
+    // netmaskLength is optional and will use the IPAM pool's default if not specified
   },
   ipv6IpamAllocation: {
     ipamPoolId: 'ipam-pool-67890',
-    netmaskLength: 64,
+    // netmaskLength is optional and will use the IPAM pool's default if not specified
   },
   assignIpv6AddressOnCreation: true,
 });
@@ -2665,3 +2665,4 @@ Note that:
 - You cannot specify both `cidrBlock` and `ipv4IpamAllocation` at the same time
 - You cannot specify both `ipv6CidrBlock` and `ipv6IpamAllocation` at the same time
 - If you specify `assignIpv6AddressOnCreation: true`, you must also specify either `ipv6CidrBlock` or `ipv6IpamAllocation`
+- The `netmaskLength` property in both `ipv4IpamAllocation` and `ipv6IpamAllocation` is optional. If not specified, the default netmask length configured in the IPAM pool will be used.

packages/aws-cdk-lib/aws-ec2/lib/vpc.ts

@@ -1974,8 +1974,12 @@ export interface Ipv4IpamAllocation {
    * The netmask length of the IPv4 CIDR to allocate to the subnet.
    *
    * Valid values are between 16 and 28.
+   *
+   * If not specified, the default netmask length configured for the IPAM pool will be used.
+   *
+   * @default - The default netmask length configured in the IPAM pool
    */
-  readonly netmaskLength: number;
+  readonly netmaskLength?: number;
 }
 
 /**
@@ -1991,8 +1995,12 @@ export interface Ipv6IpamAllocation {
    * The netmask length of the IPv6 CIDR to allocate to the subnet.
    *
    * Valid values are between 48 and 64.
+   *
+   * If not specified, the default netmask length configured for the IPAM pool will be used.
+   *
+   * @default - The default netmask length configured in the IPAM pool
    */
-  readonly netmaskLength: number;
+  readonly netmaskLength?: number;
 }
 
 /**