feat(rds): support local write forwarding for an aurora PostgreSQL cl…

…uster (aws#31803)

### Issue # (if applicable)

Closes aws#31802.

### Reason for this change



Amazon Aurora PostgreSQL now supports local write forwarding:

Whats new: https://aws.amazon.com/about-aws/whats-new/2024/10/amazon-aurora-postgresql-local-write-forwarding/

Reference: https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/aurora-postgresql-write-forwarding.html

The current CDK L2 construct only supports MySQL, but PostgreSQL needs to be supported as well.

### Description of changes



Remove the validation that engineType is either aurora or aurora-mysql, and modify docs.

### Description of how you validated changes



Both unit tests and an integ test.

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https:/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https:/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-testing/framework-integ/test/aws-rds/test/integ.cluster-enable-local-write-forwarding.js.snapshot/EnableLocalWriteForwardingClusterStack.template.json

@@ -670,6 +670,163 @@
  ],
  "UpdateReplacePolicy": "Delete",
  "DeletionPolicy": "Delete"
+ },
+ "DatabaseClusterPostgresqlSubnetsE0173DAA": {
+ "Type": "AWS::RDS::DBSubnetGroup",
+ "Properties": {
+ "DBSubnetGroupDescription": "Subnets for DatabaseClusterPostgresql database",
+ "SubnetIds": [
+ {
+ "Ref": "VPCPrivateSubnet1Subnet8BCA10E0"
+ },
+ {
+ "Ref": "VPCPrivateSubnet2SubnetCFCDAA7A"
+ }
+ ]
+ }
+ },
+ "DatabaseClusterPostgresqlSecurityGroupEF4103D2": {
+ "Type": "AWS::EC2::SecurityGroup",
+ "Properties": {
+ "GroupDescription": "RDS security group",
+ "SecurityGroupEgress": [
+ {
+ "CidrIp": "0.0.0.0/0",
+ "Description": "Allow all outbound traffic by default",
+ "IpProtocol": "-1"
+ }
+ ],
+ "VpcId": {
+ "Ref": "VPCB9E5F0B4"
+ }
+ }
+ },
+ "DatabaseClusterPostgresqlSecretD2D9C157": {
+ "Type": "AWS::SecretsManager::Secret",
+ "Properties": {
+ "Description": {
+ "Fn::Join": [
+ "",
+ [
+ "Generated by the CDK for stack: ",
+ {
+ "Ref": "AWS::StackName"
+ }
+ ]
+ ]
+ },
+ "GenerateSecretString": {
+ "ExcludeCharacters": " %+~`#$&*()|[]{}:;<>?!'/@\"\\",
+ "GenerateStringKey": "password",
+ "PasswordLength": 30,
+ "SecretStringTemplate": "{\"username\":\"postgres\"}"
+ }
+ },
+ "UpdateReplacePolicy": "Delete",
+ "DeletionPolicy": "Delete"
+ },
+ "DatabaseClusterPostgresqlSecretAttachment09D32DC9": {
+ "Type": "AWS::SecretsManager::SecretTargetAttachment",
+ "Properties": {
+ "SecretId": {
+ "Ref": "DatabaseClusterPostgresqlSecretD2D9C157"
+ },
+ "TargetId": {
+ "Ref": "DatabaseClusterPostgresql0775776E"
+ },
+ "TargetType": "AWS::RDS::DBCluster"
+ }
+ },
+ "DatabaseClusterPostgresql0775776E": {
+ "Type": "AWS::RDS::DBCluster",
+ "Properties": {
+ "CopyTagsToSnapshot": true,
+ "DBClusterParameterGroupName": "default.aurora-postgresql16",
+ "DBSubnetGroupName": {
+ "Ref": "DatabaseClusterPostgresqlSubnetsE0173DAA"
+ },
+ "EnableLocalWriteForwarding": true,
+ "Engine": "aurora-postgresql",
+ "EngineVersion": "16.4",
+ "MasterUserPassword": {
+ "Fn::Join": [
+ "",
+ [
+ "{{resolve:secretsmanager:",
+ {
+ "Ref": "DatabaseClusterPostgresqlSecretD2D9C157"
+ },
+ ":SecretString:password::}}"
+ ]
+ ]
+ },
+ "MasterUsername": {
+ "Fn::Join": [
+ "",
+ [
+ "{{resolve:secretsmanager:",
+ {
+ "Ref": "DatabaseClusterPostgresqlSecretD2D9C157"
+ },
+ ":SecretString:username::}}"
+ ]
+ ]
+ },
+ "Port": 5432,
+ "ServerlessV2ScalingConfiguration": {
+ "MaxCapacity": 2,
+ "MinCapacity": 0.5
+ },
+ "VpcSecurityGroupIds": [
+ {
+ "Fn::GetAtt": [
+ "DatabaseClusterPostgresqlSecurityGroupEF4103D2",
+ "GroupId"
+ ]
+ }
+ ]
+ },
+ "UpdateReplacePolicy": "Snapshot",
+ "DeletionPolicy": "Snapshot"
+ },
+ "DatabaseClusterPostgresqlwriterInstanceB16652DD": {
+ "Type": "AWS::RDS::DBInstance",
+ "Properties": {
+ "DBClusterIdentifier": {
+ "Ref": "DatabaseClusterPostgresql0775776E"
+ },
+ "DBInstanceClass": "db.serverless",
+ "Engine": "aurora-postgresql",
+ "PromotionTier": 0
+ },
+ "DependsOn": [
+ "VPCPrivateSubnet1DefaultRouteAE1D6490",
+ "VPCPrivateSubnet1RouteTableAssociation347902D1",
+ "VPCPrivateSubnet2DefaultRouteF4F5CFD2",
+ "VPCPrivateSubnet2RouteTableAssociation0C73D413"
+ ],
+ "UpdateReplacePolicy": "Delete",
+ "DeletionPolicy": "Delete"
+ },
+ "DatabaseClusterPostgresqlreaderInstance10798C6B0": {
+ "Type": "AWS::RDS::DBInstance",
+ "Properties": {
+ "DBClusterIdentifier": {
+ "Ref": "DatabaseClusterPostgresql0775776E"
+ },
+ "DBInstanceClass": "db.serverless",
+ "Engine": "aurora-postgresql",
+ "PromotionTier": 2
+ },
+ "DependsOn": [
+ "DatabaseClusterPostgresqlwriterInstanceB16652DD",
+ "VPCPrivateSubnet1DefaultRouteAE1D6490",
+ "VPCPrivateSubnet1RouteTableAssociation347902D1",
+ "VPCPrivateSubnet2DefaultRouteF4F5CFD2",
+ "VPCPrivateSubnet2RouteTableAssociation0C73D413"
+ ],
+ "UpdateReplacePolicy": "Delete",
+ "DeletionPolicy": "Delete"
  }
  },
  "Mappings": {