feat: centralize ARN validation with isValidArn utility

Author: Hweinstock

src/cli/commands/add/validate.ts

@@ -15,6 +15,7 @@ import {
   getSupportedModelProviders,
   matchEnumValue,
 } from '../../../schema';
+import { ARN_VALIDATION_MESSAGE, isValidArn } from '../shared/arn-utils';
 import { parseAndValidateLifecycleOptions } from '../shared/lifecycle-utils';
 import { validateVpcOptions } from '../shared/vpc-utils';
 import { validateJwtAuthorizerOptions } from './auth-options';
@@ -697,8 +698,8 @@ export function validateAddMemoryOptions(options: AddMemoryOptions): ValidationR
     return { valid: false, error: '--data-stream-arn is required when --delivery-type is set' };
   }
 
-  if (options.dataStreamArn && !options.dataStreamArn.startsWith('arn:')) {
-    return { valid: false, error: '--data-stream-arn must be a valid ARN (starts with arn:)' };
+  if (options.dataStreamArn && !isValidArn(options.dataStreamArn)) {
+    return { valid: false, error: `--data-stream-arn: ${ARN_VALIDATION_MESSAGE}` };
   }
 
   if (

src/cli/commands/shared/__tests__/arn-utils.test.ts

@@ -0,0 +1,28 @@
+import { isValidArn } from '../arn-utils';
+import { describe, expect, it } from 'vitest';
+
+describe('isValidArn', () => {
+  it('accepts a valid Kinesis stream ARN', () => {
+    expect(isValidArn('arn:aws:kinesis:us-west-2:123456789012:stream/my-stream')).toBe(true);
+  });
+
+  it('accepts a valid Lambda ARN', () => {
+    expect(isValidArn('arn:aws:lambda:us-east-1:123456789012:function:my-func')).toBe(true);
+  });
+
+  it('rejects a string that does not start with arn:', () => {
+    expect(isValidArn('not-an-arn')).toBe(false);
+  });
+
+  it('rejects an ARN with too few parts', () => {
+    expect(isValidArn('arn:aws:kinesis:us-west-2:123456789012')).toBe(false);
+  });
+
+  it('accepts an ARN with colons in the resource part', () => {
+    expect(isValidArn('arn:aws:kinesis:us-west-2:123456789012:stream:extra:parts')).toBe(true);
+  });
+
+  it('rejects an empty string', () => {
+    expect(isValidArn('')).toBe(false);
+  });
+});

src/cli/commands/shared/arn-utils.ts

@@ -0,0 +1,11 @@
+const ARN_PART_COUNT = 6;
+const ARN_FORMAT = 'arn:partition:service:region:account:resource';
+
+/**
+ * Check whether a string looks like a valid ARN (starts with `arn:` and has at least 6 colon-separated parts).
+ */
+export function isValidArn(value: string): boolean {
+  return value.startsWith('arn:') && value.split(':').length >= ARN_PART_COUNT;
+}
+
+export const ARN_VALIDATION_MESSAGE = `Must be a valid ARN (${ARN_FORMAT})`;

src/cli/tui/screens/memory/AddMemoryScreen.tsx

@@ -1,5 +1,6 @@
 import type { MemoryStrategyType } from '../../../../schema';
 import { AgentNameSchema, StreamContentLevelSchema } from '../../../../schema';
+import { ARN_VALIDATION_MESSAGE, isValidArn } from '../../../commands/shared/arn-utils';
 import {
   ConfirmReview,
   Panel,
@@ -173,7 +174,7 @@ export function AddMemoryScreen({ onComplete, onExit, existingMemoryNames }: Add
             initialValue=""
             onSubmit={wizard.setStreamArn}
             onCancel={() => wizard.goBack()}
-            customValidation={value => value.startsWith('arn:') || 'Must be a valid ARN (starts with arn:)'}
+            customValidation={value => isValidArn(value) || ARN_VALIDATION_MESSAGE}
           />
         )}