Object resource conversion error using Ec2TaskDefinition.from_ec2_task_definition_arn with ApplicationLoadBalancedEc2Service

[ghost]

• When using a task definition object (Ec2TaskDefinition.from_ec2_task_definition_arn) in ApplicationLoadBalancedEc2Service pattern, i get the following error:

jsii.errors.JSIIError: Object of type @aws-cdk/core.Resource is not convertible to @aws-cdk/aws-ecs.Ec2TaskDefinition

Reproduction Steps

python code:

        task_arn = (
            "arn:aws:ecs:<regionacctredacted>task-definition/mytask"
        )

        task_definition = ecs.Ec2TaskDefinition.from_ec2_task_definition_arn(
            self, "my_task_def", task_arn
        )

        loadbalanced_service = patterns.ApplicationLoadBalancedEc2Service(
            self,
            "loadbalance_service",
            cluster=ecs_cluster, <- ecs cluster code not included here, just a regular ec2 cluster 
            task_definition=task_definition
        )

Error Log

Traceback (most recent call last):
  File "app.py", line 20, in <module>
  File "/.env/lib/python3.7/site-packages/jsii/_runtime.py", line 66, in __call__
    inst = super().__call__(*args, **kwargs)
  File "/stack.py", line 83, in __init__
    task_definition=task_definition,
  File "/.env/lib/python3.7/site-packages/jsii/_runtime.py", line 66, in __call__
    inst = super().__call__(*args, **kwargs)
  File "/.env/lib/python3.7/site-packages/aws_cdk/aws_ecs_patterns/__init__.py", line 3286, in __init__
    jsii.create(ApplicationLoadBalancedEc2Service, self, [scope, id, props])
  File "/.env/lib/python3.7/site-packages/jsii/_kernel/__init__.py", line 229, in create
    interfaces=[iface.__jsii_type__ for iface in getattr(klass, "__jsii_ifaces__", [])],
  File "/.env/lib/python3.7/site-packages/jsii/_kernel/providers/process.py", line 333, in create
    return self._process.send(request, CreateResponse)
  File "/.env/lib/python3.7/site-packages/jsii/_kernel/providers/process.py", line 318, in send
    raise JSIIError(resp.error) from JavaScriptError(resp.stack)
jsii.errors.JSIIError: Object of type @aws-cdk/core.Resource is not convertible to @aws-cdk/aws-ecs.Ec2TaskDefinition
Subprocess exited with error 1

Environment

• CLI Version : 1.18.77
• **Framework Version:**1.45.0
• Node.js Version: 12.13.1
• OS : mac os 10.15.4
• Language (Version): python 3.7

Other

Looks like during synthesis, the task definition object is a core.resource and cannot be converted to what is needed for the pattern.

I feel like this is a bug. I asked around various forums/slack channels but no answers as yet.

It looks like i'm using this correctly, but honestly this is the first time i'm using this construct/pattern and there are no real good examples on using this i can get a bearing on( or at least any that i can find). So it's entirely possible i'm not using this right.

When i comment out the service pattern, things synthesize with no problems.

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This is 🐛 Bug Report

[SoManyHs]

Related: #6240

[SoManyHs]

Closing as a duplicate of abovementioned issue -- let us know if you have other questions!