feat(ecs): ability to access tag parameter value of TagParameterConta…

…inerImage

Allows you to use the tag elsewhere within the container definition (e.g. to inform monitoring services of the release version).

fixes: aws#13202

packages/@aws-cdk/aws-ecs/lib/images/tag-parameter-container-image.ts

@@ -49,4 +49,20 @@ export class TagParameterContainerImage extends ContainerImage {
  },
  });
  }
+
+ /**
+ * Returns the value of the CloudFormation Parameter that represents the tag of the image
+ * in the ECR repository.
+ */
+ public get tagParameterValue(): string {
+ return cdk.Lazy.string({
+ produce: () => {
+ if (this.imageTagParameter) {
+ return this.imageTagParameter.writeAsString;
+ } else {
+ throw new Error('TagParameterContainerImage must be used in a container definition when using tagParameterValue');
+ }
+ },
+ });
+ }
 }

packages/@aws-cdk/aws-ecs/test/images/tag-parameter-container-image.test.ts

@@ -19,6 +19,21 @@ nodeunitShim({
  SynthUtils.synthesize(stack);
  }, /TagParameterContainerImage must be used in a container definition when using tagParameterName/);
 
+ test.done();
+ },
+ 'throws an error when tagParameterValue() is used without binding the image'(test: Test) {
+ // GIVEN
+ const stack = new cdk.Stack();
+ const repository = new ecr.Repository(stack, 'Repository');
+ const tagParameterContainerImage = new ecs.TagParameterContainerImage(repository);
+ new cdk.CfnOutput(stack, 'Output', {
+ value: tagParameterContainerImage.tagParameterValue,
+ });
+
+ test.throws(() => {
+ SynthUtils.synthesize(stack);
+ }, /TagParameterContainerImage must be used in a container definition when using tagParameterValue/);
+
  test.done();
  },
  },