feat(redshift): support default role for redshift clusters

packages/@aws-cdk/aws-redshift/README.md

@@ -386,3 +386,48 @@ new Cluster(stack, 'Redshift', {
 ```
 
 If enhanced VPC routing is not enabled, Amazon Redshift routes traffic through the internet, including traffic to other services within the AWS network.
+
+## Default IAM role
+
+Some Amazon Redshift features require Amazon Redshift to access other AWS services on your behalf. For your Amazon Redshift clusters to act on your behalf, you supply security credentials to your clusters. The preferred method to supply security credentials is to specify an AWS Identity and Access Management (IAM) role.
+
+When you create an IAM role and set it as the default for the cluster using console, you don't have to provide the IAM role's Amazon Resource Name (ARN) to perform authentication and authorization.
+
+```ts
+declare const vpc: ec2.Vpc;
+
+const defaultRole = new iam.Role(this, 'DefaultRole', {
+  assumedBy: new iam.ServicePrincipal('redshift.amazonaws.com'),
+},
+);
+
+new Cluster(stack, 'Redshift', {
+    masterUser: {
+      masterUsername: 'admin',
+    },
+    vpc,
+    roles: [defaultRole],
+    defaultRole: defaultRole,
+});
+```
+
+A default role can also be added to a cluster using the `addDefaultIamRole` method.
+
+```ts
+declare const vpc: ec2.Vpc;
+
+const defaultRole = new iam.Role(this, 'DefaultRole', {
+  assumedBy: new iam.ServicePrincipal('redshift.amazonaws.com'),
+},
+);
+
+const redshiftCluster = new Cluster(stack, 'Redshift', {
+    masterUser: {
+      masterUsername: 'admin',
+    },
+    vpc,
+    roles: [defaultRole],
+});
+
+redshiftCluster.addDefaultIamRole(defaultRole);
+```

packages/@aws-cdk/aws-redshift/lib/cluster.ts

@@ -4,6 +4,7 @@ import * as kms from '@aws-cdk/aws-kms';
 import * as s3 from '@aws-cdk/aws-s3';
 import * as secretsmanager from '@aws-cdk/aws-secretsmanager';
 import { Duration, IResource, RemovalPolicy, Resource, SecretValue, Token } from '@aws-cdk/core';
+import { AwsCustomResource, PhysicalResourceId, AwsCustomResourcePolicy } from '@aws-cdk/custom-resources';
 import { Construct } from 'constructs';
 import { DatabaseSecret } from './database-secret';
 import { Endpoint } from './endpoint';
@@ -304,6 +305,14 @@ export interface ClusterProps {
    */
   readonly roles?: iam.IRole[];
 
+  /**
+   * A single AWS Identity and Access Management (IAM) role to be used as the default role for the cluster.
+   * The default role must be included in the roles list.
+   *
+   * @default - No default role is specified for the cluster.
+   */
+  readonly defaultRole?: iam.IRole;
+
   /**
    * Name of a database which is automatically created inside the cluster
    *
@@ -575,6 +584,15 @@ export class Cluster extends ClusterBase {
 
     const defaultPort = ec2.Port.tcp(this.clusterEndpoint.port);
     this.connections = new ec2.Connections({ securityGroups, defaultPort });
+
+    // Add default role if specified and also available in the roles list
+    if (props.defaultRole) {
+      if (props.roles?.some(x => x === props.defaultRole)) {
+        this.addDefaultIamRole(props.defaultRole);
+      } else {
+        throw new Error('Default role must be included in role list.');
+      }
+    }
   }
 
   /**
@@ -662,4 +680,57 @@ export class Cluster extends ClusterBase {
       throw new Error('Cannot add a parameter to an imported parameter group.');
     }
   }
+
+  /**
+   * Adds default IAM role to cluster. The default IAM role must be already associated to the cluster to be added as the default role.
+   *
+   * @param defaultIamRole the IAM role to be set as the default role
+   */
+  public addDefaultIamRole(defaultIamRole: iam.IRole): void {
+    // Get list of IAM roles attached to cluster
+    const clusterRoleList = this.cluster.iamRoles ?? [];
+
+    // Check to see if default role is included in list of cluster IAM roles
+    var roleAlreadyOnCluster = false;
+    for (var i = 0; i < clusterRoleList.length; i++) {
+      if (clusterRoleList[i] == defaultIamRole.roleArn) {
+        roleAlreadyOnCluster = true;
+        break;
+      }
+    }
+    if (!roleAlreadyOnCluster) {
+      throw new Error('Default role must be associated to the Redshift cluster to be set as the default role.');
+    }
+
+    // On UPDATE or CREATE define the default IAM role. On DELETE, remove the default IAM role
+    const defaultRoleCustomResource = new AwsCustomResource(this, 'default-role', {
+      onUpdate: {
+        service: 'Redshift',
+        action: 'modifyClusterIamRoles',
+        parameters: {
+          ClusterIdentifier: this.cluster.ref,
+          DefaultIamRoleArn: defaultIamRole.roleArn,
+        },
+        physicalResourceId: PhysicalResourceId.of(
+          `${defaultIamRole.roleArn}-${this.cluster.ref}`,
+        ),
+      },
+      onDelete: {
+        service: 'Redshift',
+        action: 'modifyClusterIamRoles',
+        parameters: {
+          ClusterIdentifier: this.cluster.ref,
+          DefaultIamRoleArn: '',
+        },
+        physicalResourceId: PhysicalResourceId.of(
+          `${defaultIamRole.roleArn}-${this.cluster.ref}`,
+        ),
+      },
+      policy: AwsCustomResourcePolicy.fromSdkCalls({
+        resources: AwsCustomResourcePolicy.ANY_RESOURCE,
+      }),
+    });
+
+    defaultIamRole.grantPassRole(defaultRoleCustomResource.grantPrincipal);
+  }
 }

packages/@aws-cdk/aws-redshift/test/cluster.test.ts

@@ -1,5 +1,6 @@
 import { Match, Template } from '@aws-cdk/assertions';
 import * as ec2 from '@aws-cdk/aws-ec2';
+import * as iam from '@aws-cdk/aws-iam';
 import * as kms from '@aws-cdk/aws-kms';
 import * as s3 from '@aws-cdk/aws-s3';
 import * as cdk from '@aws-cdk/core';
@@ -613,6 +614,40 @@ test('elastic ip address', () => {
   });
 });
 
+describe('default IAM role', () => {
+
+  test('Default role not in role list', () => {
+    // GIVEN
+    const clusterRole1 = new iam.Role(stack, 'clusterRole1', { assumedBy: new iam.ServicePrincipal('redshift.amazonaws.com') } );
+    const defaultRole1 = new iam.Role(stack, 'defaultRole1', { assumedBy: new iam.ServicePrincipal('redshift.amazonaws.com') } );
+
+    expect(() => {
+      new Cluster(stack, 'Redshift', {
+        masterUser: {
+          masterUsername: 'admin',
+        },
+        vpc,
+        roles: [clusterRole1],
+        defaultRole: defaultRole1,
+      });
+    }).toThrow(/Default role must be included in role list./);
+  });
+
+  test('throws error when default role not attached to cluster when adding default role post creation', () => {
+    const defaultRole1 = new iam.Role(stack, 'defaultRole1', { assumedBy: new iam.ServicePrincipal('redshift.amazonaws.com') } );
+    const cluster = new Cluster(stack, 'Redshift', {
+      masterUser: {
+        masterUsername: 'admin',
+      },
+      vpc,
+    });
+
+    expect(() => {
+      cluster.addDefaultIamRole(defaultRole1);
+    }).toThrow(/Default role must be associated to the Redshift cluster to be set as the default role./);
+  });
+});
+
 function testStack() {
   const newTestStack = new cdk.Stack(undefined, undefined, { env: { account: '12345', region: 'us-test-1' } });
   newTestStack.node.setContext('availability-zones:12345:us-test-1', ['us-test-1a', 'us-test-1b']);

packages/@aws-cdk/aws-redshift/test/integ.cluster-defaultiamrole.js.snapshot/DefaultIamRoleIntegDefaultTestDeployAssert161B8D72.assets.json

@@ -0,0 +1,19 @@
+{
+  "version": "22.0.0",
+  "files": {
+    "21fbb51d7b23f6a6c262b46a9caee79d744a3ac019fd45422d988b96d44b2a22": {
+      "source": {
+        "path": "DefaultIamRoleIntegDefaultTestDeployAssert161B8D72.template.json",
+        "packaging": "file"
+      },
+      "destinations": {
+        "current_account-current_region": {
+          "bucketName": "cdk-hnb659fds-assets-${AWS::AccountId}-${AWS::Region}",
+          "objectKey": "21fbb51d7b23f6a6c262b46a9caee79d744a3ac019fd45422d988b96d44b2a22.json",
+          "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-file-publishing-role-${AWS::AccountId}-${AWS::Region}"
+        }
+      }
+    }
+  },
+  "dockerImages": {}
+}

packages/@aws-cdk/aws-redshift/test/integ.cluster-defaultiamrole.js.snapshot/DefaultIamRoleIntegDefaultTestDeployAssert161B8D72.template.json

@@ -0,0 +1,36 @@
+{
+ "Parameters": {
+  "BootstrapVersion": {
+   "Type": "AWS::SSM::Parameter::Value<String>",
+   "Default": "/cdk-bootstrap/hnb659fds/version",
+   "Description": "Version of the CDK Bootstrap resources in this environment, automatically retrieved from SSM Parameter Store. [cdk:skip]"
+  }
+ },
+ "Rules": {
+  "CheckBootstrapVersion": {
+   "Assertions": [
+    {
+     "Assert": {
+      "Fn::Not": [
+       {
+        "Fn::Contains": [
+         [
+          "1",
+          "2",
+          "3",
+          "4",
+          "5"
+         ],
+         {
+          "Ref": "BootstrapVersion"
+         }
+        ]
+       }
+      ]
+     },
+     "AssertDescription": "CDK bootstrap stack version 6 required. Please run 'cdk bootstrap' with a recent version of the CDK CLI."
+    }
+   ]
+  }
+ }
+}