ECS.client.create_service() Incorrectly Requiring loadBalancers param

Attempting to run ECS.client.create_service() without a load balancer. Per the documentation, loadBalancers parameter is not required: https://boto3.readthedocs.org/en/latest/reference/services/ecs.html#ECS.Client.create_service

When executed via boto3, I’m seeing the following error:

(Error code 400)
  File "/usr/local/lib/python3.5/site-packages/botocore/client.py", line 310, in _api_call
    return self._make_api_call(operation_name, kwargs)
  File "/usr/local/lib/python3.5/site-packages/botocore/client.py", line 407, in _make_api_call
    raise ClientError(parsed_response, operation_name)
  botocore.exceptions.ClientError: An error occurred (InvalidParameterException) when calling the CreateService operation: A role was passed, but no load balancers were present.

The aws_cli tool does not require the loadBalancers parameter.

[mccammon]

Removing role fixes the issue. It appears that there is some confusion on whether adding a role param means that loadBalancers param is required:

https://boto3.readthedocs.org/en/latest/reference/services/ecs.html#ECS.Client.create_service role:…“This parameter is only required if you are using a load balancer with your service.”

As stated before, role can be used with the aws_cli tool without requiring loadBalancers.

[swetashre]

@mccammon - Not the documentation is updated with more detail. You can see in our documentation https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/ecs.html#ECS.Client.create_service:

Role: This parameter is only permitted if you are using a load balancer with your service and your task definition does not use the awsvpc network mode. If you specify the role parameter, you must also specify a load balancer object with the loadBalancers parameter.

I am closing the issue as the issue has been resolved.