ECS run_task creates no containers

[jvdmr]

After registering a task definition, run_task (and create_service, and other calls) using this task definition creates a Task object, but this object never gets any containers. The containers attribute remains an empty list at all times.

I would expect the containerDefinitions in the task definition to be used to create a mock representation of the containers the task supposedly would start.

code:

        ecs_client: botostubs.ECS = boto3.client('ecs')
        cluster = ecs_client.create_cluster().get('cluster')
        task_definition = ecs_client.register_task_definition(
            family='my-service',
            containerDefinitions=[{
                'name': 'myContainer',
                'image': 'debian',
                'memory': 1024,
            }],
        ).get('taskDefinition')
        task = ecs_client.run_task(
            taskDefinition=task_definition.get('taskDefinitionArn'),
            cluster=cluster.get('clusterName'),
            launchType='FARGATE',
        ).get('tasks')[0]
        print(json.dumps(task, indent=2)

output:

{
  "attachments": [],
  "clusterArn": "arn:aws:ecs:eu-west-1:123456789012:cluster/default",
  "containers": [],
  "desiredStatus": "RUNNING",
  "lastStatus": "RUNNING",
  "launchType": "FARGATE",
  "overrides": {},
  "startedBy": "",
  "stoppedReason": "",
  "tags": [],
  "taskArn": "arn:aws:ecs:eu-west-1:123456789012:task/default/d17f38b6-4eba-45c9-a9aa-226f97c8db23",
  "taskDefinitionArn": "arn:aws:ecs:eu-west-1:123456789012:task-definition/my-service:1"
}

I realize this is not a bug but rather incomplete implementation, but since I couldn't find any other mentions of it, I decided to create a ticket to keep track of any ongoing development.