Create ECS Service with existing task definition ARN

Reproduction Steps

Now our customers cannot create an ECS service using an existing task definition ARN although we have fromFargateTaskDefinitionARN() and fromEc2TaskDefinitionARN().

Related to https://github.com/aws-samples/aws-cdk-examples/issues/112

Error Log

Environment

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This is 🐛 Bug Report

[cajames]

For anyone still trying to create a service with a task definition ARN, here’s a temporary workaround. It can be done with “Raw Overrides”. Documented here: https://docs.aws.amazon.com/cdk/latest/guide/cfn_layer.html

You’ll need to create a service with a temporary task definition (can be done easily with CDK), and then overwrite that Task Definition with a new Task Definition.

Our reasons for using this is similar to @machielg, to mount an EFS volume to a Fargate task, which is not currently supported by CloudFormation.

I found this technique in @michaelmoussa’s example.

So in this case:

fargateService.addPropertyOverride('TaskDefinition', customResourceTaskDefinitionArn);

Here’s a gist showing how to create a Fargate + EFS service currently, adapted from @michaelmoussa’s examples. Hope this can help anyone, while the main issue is being fixed.

https://gist.github.com/cajames/3daec680b1101c8358e2ff30dfadd52a

[b3n3d1k7]

For anyone still trying to create a service with a task definition ARN, here’s a temporary workaround. It can be done with “Raw Overrides”. Documented here: https://docs.aws.amazon.com/cdk/latest/guide/cfn_layer.html

You’ll need to create a service with a temporary task definition (can be done easily with CDK), and then overwrite that Task Definition with a new Task Definition.

Our reasons for using this is similar to @machielg, to mount an EFS volume to a Fargate task, which is not currently supported by CloudFormation.

I found this technique in @michaelmoussa’s example.

So in this case:

fargateService.addPropertyOverride('TaskDefinition', customResourceTaskDefinitionArn);

Here’s a gist showing how to create a Fargate + EFS service currently, adapted from @michaelmoussa’s examples. Hope this can help anyone, while the main issue is being fixed.

https://gist.github.com/cajames/3daec680b1101c8358e2ff30dfadd52a

Because I just spent a few hours trying to figure out why using addPropertyOverride didn’t work and resulted in strange error messages about invalid parameter types during deployment, maybe this is useful for someone else. Set the task-definition using the member instead of using addPropertyOverride:

# instead of this
(service.service.node.tryFindChild('Service') as CfnService)?.addPropertyOverride(
  'TaskDefinition',
  customTaskDefinition.getResponseField('taskDefinition.taskDefinitionArn'),
);

# use this
(service.service.node.tryFindChild('Service') as CfnService).taskDefinition = customTaskDefinition.getResponseField('taskDefinition.taskDefinitionArn');

Note: Using addPropertyOverride resulted in both, the old and the new task-definition attached to the service in the cloudformation template for me.