fix(ecs): remove unnecessary error when adding volume to external tas…

…k definition (#19774)

fixes #19259

----

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packages/@aws-cdk/aws-ecs/lib/external/external-task-definition.ts

@@ -8,7 +8,6 @@ import {
  ITaskDefinition,
  NetworkMode,
  TaskDefinition,
- Volume,
 } from '../base/task-definition';
 
 /**
@@ -75,13 +74,6 @@ export class ExternalTaskDefinition extends TaskDefinition implements IExternalT
  });
  }
 
- /**
- * Overridden method to throw error, as volumes are not supported for external task definitions
- */
- public addVolume(_volume: Volume) {
- throw new Error('External task definitions doesnt support volumes');
- }
-
  /**
  * Overriden method to throw error as interface accelerators are not supported for external tasks
  */

packages/@aws-cdk/aws-ecs/test/external/external-task-definition.test.ts

@@ -601,17 +601,30 @@ describe('external task definition', () => {
  Annotations.fromStack(stack).hasWarning('/Default/ExternalTaskDef/web', "Proper policies need to be attached before pulling from ECR repository, or use 'fromEcrRepository'.");
  });
 
- test('correctly sets volumes from', () => {
+ test('correctly sets volumes', () => {
+ // GIVEN
  const stack = new cdk.Stack();
  const taskDefinition = new ecs.ExternalTaskDefinition(stack, 'ExternalTaskDef', {});
 
- // THEN
- expect(() => taskDefinition.addVolume({
+ // WHEN
+ taskDefinition.addVolume({
  host: {
  sourcePath: '/tmp/cache',
  },
  name: 'scratch',
- })).toThrow('External task definitions doesnt support volumes' );
+ });
+
+ // THEN
+ Template.fromStack(stack).hasResourceProperties('AWS::ECS::TaskDefinition', {
+ Volumes: [
+ {
+ Host: {
+ SourcePath: '/tmp/cache',
+ },
+ Name: 'scratch',
+ },
+ ],
+ });
  });
 
  test('error when interferenceAccelerators set', () => {