fix(eks-v2-alpha): prevent IAM role creation when node pools are empty

packages/@aws-cdk/aws-eks-v2-alpha/README.md

@@ -148,6 +148,22 @@ const cluster = new eks.Cluster(this, 'EksAutoCluster', {
 
 For more information, see [Create a Node Pool for EKS Auto Mode](https://docs.aws.amazon.com/eks/latest/userguide/create-node-pool.html).
 
+### Disabling Default Node Pools
+
+You can disable the default node pools entirely by setting an empty array for `nodePools`. This is useful when you want to use Auto Mode features but manage your compute resources separately:
+
+```ts
+const cluster = new eks.Cluster(this, 'EksAutoCluster', {
+  version: eks.KubernetesVersion.V1_32,
+  defaultCapacityType: eks.DefaultCapacityType.AUTOMODE,
+  compute: {
+    nodePools: [], // Disable default node pools
+  },
+});
+```
+
+When node pools are disabled this way, no IAM role will be created for the node pools, preventing deployment failures that would otherwise occur when a role is created without any node pools.
+
 ### Node Groups as the default capacity type
 
 If you prefer to manage your own node groups instead of using Auto Mode, you can use the traditional node group approach by specifying `defaultCapacityType` as `NODEGROUP`:

packages/@aws-cdk/aws-eks-v2-alpha/lib/cluster.ts

@@ -1184,8 +1184,11 @@ export class Cluster extends ClusterBase {
         enabled: autoModeEnabled,
         // If the computeConfig enabled flag is set to false when creating a cluster with Auto Mode,
         // the request must not include values for the nodeRoleArn or nodePools fields.
+        // Also, if nodePools is empty, nodeRoleArn should not be included to prevent deployment failures
         nodePools: !autoModeEnabled ? undefined : props.compute?.nodePools ?? ['system', 'general-purpose'],
-        nodeRoleArn: !autoModeEnabled ? undefined : props.compute?.nodeRole?.roleArn ?? this.addNodePoolRole(`${id}nodePoolRole`).roleArn,
+        nodeRoleArn: !autoModeEnabled || (props.compute?.nodePools && props.compute.nodePools.length === 0) ?
+          undefined :
+          props.compute?.nodeRole?.roleArn ?? this.addNodePoolRole(`${id}nodePoolRole`).roleArn,
       },
       storageConfig: {
         blockStorage: {

packages/@aws-cdk/aws-eks-v2-alpha/test/automode.test.ts

@@ -235,6 +235,43 @@ describe('eks auto mode', () => {
         },
       });
     });
+
+    test('does not include nodeRoleArn when nodePools is empty', () => {
+      const { stack } = testFixtureNoVpc();
+
+      new eks.Cluster(stack, 'Cluster', {
+        version: CLUSTER_VERSION,
+        defaultCapacityType: eks.DefaultCapacityType.AUTOMODE,
+        compute: {
+          nodePools: [],
+        },
+      });
+
+      // Verify that nodeRoleArn is not included in the CloudFormation template
+      Template.fromStack(stack).hasResourceProperties('AWS::EKS::Cluster', {
+        ComputeConfig: {
+          Enabled: true,
+          NodePools: [],
+        },
+      });
+
+      // Verify that nodeRoleArn is not present in the ComputeConfig
+      const template = Template.fromStack(stack);
+      const cluster = template.findResources('AWS::EKS::Cluster');
+      const clusterLogicalId = Object.keys(cluster)[0];
+      const computeConfig = cluster[clusterLogicalId].Properties.ComputeConfig;
+
+      expect(computeConfig).not.toHaveProperty('NodeRoleArn');
+
+      // Verify that no IAM role resource is created for node pools
+      // The role would typically have a logical ID like 'ClusterClusternodePoolRole...'
+      const iamRoles = template.findResources('AWS::IAM::Role');
+      const nodePoolRoleKeys = Object.keys(iamRoles).filter(key =>
+        key.includes('nodePoolRole'),
+      );
+
+      expect(nodePoolRoleKeys.length).toBe(0);
+    });
   });
 
   describe('network configuration', () => {