Specifying `arguments=[]` in SKLearnProcessor.run() causes `Invalid length for parameter AppSpecification.ContainerArguments` error

[cfregly]

This code:

sklearn_processor.run(code='preprocess-scikit.py',
                                       arguments=[])                     

Causes the following error:

---------------------------------------------------------------------------
ParamValidationError                      Traceback (most recent call last)
<ipython-input-88-829761199960> in <module>()
     12                       arguments=[],
     13                       logs=True,
---> 14                       wait=False)

~/anaconda3/envs/python3/lib/python3.6/site-packages/sagemaker/processing.py in run(self, code, inputs, outputs, arguments, wait, logs, job_name, experiment_config)
    402             inputs=normalized_inputs,
    403             outputs=normalized_outputs,
--> 404             experiment_config=experiment_config,
    405         )
    406         self.jobs.append(self.latest_job)

~/anaconda3/envs/python3/lib/python3.6/site-packages/sagemaker/processing.py in start_new(cls, processor, inputs, outputs, experiment_config)
    622 
    623         # Call sagemaker_session.process using the arguments dictionary.
--> 624         processor.sagemaker_session.process(**process_request_args)
    625 
    626         return cls(

~/anaconda3/envs/python3/lib/python3.6/site-packages/sagemaker/session.py in process(self, inputs, output_config, job_name, resources, stopping_condition, app_specification, environment, network_config, role_arn, tags, experiment_config)
    644         LOGGER.info("Creating processing-job with name %s", job_name)
    645         LOGGER.debug("process request: %s", json.dumps(process_request, indent=4))
--> 646         self.sagemaker_client.create_processing_job(**process_request)
    647 
    648     def create_monitoring_schedule(

~/anaconda3/envs/python3/lib/python3.6/site-packages/botocore/client.py in _api_call(self, *args, **kwargs)
    314                     "%s() only accepts keyword arguments." % py_operation_name)
    315             # The "self" in this scope is referring to the BaseClient.
--> 316             return self._make_api_call(operation_name, kwargs)
    317 
    318         _api_call.__name__ = str(py_operation_name)

~/anaconda3/envs/python3/lib/python3.6/site-packages/botocore/client.py in _make_api_call(self, operation_name, api_params)
    597         }
    598         request_dict = self._convert_to_request_dict(
--> 599             api_params, operation_model, context=request_context)
    600 
    601         service_id = self._service_model.service_id.hyphenize()

~/anaconda3/envs/python3/lib/python3.6/site-packages/botocore/client.py in _convert_to_request_dict(self, api_params, operation_model, context)
    645             api_params, operation_model, context)
    646         request_dict = self._serializer.serialize_to_request(
--> 647             api_params, operation_model)
    648         if not self._client_config.inject_host_prefix:
    649             request_dict.pop('host_prefix', None)

~/anaconda3/envs/python3/lib/python3.6/site-packages/botocore/validate.py in serialize_to_request(self, parameters, operation_model)
    295                                                     operation_model.input_shape)
    296             if report.has_errors():
--> 297                 raise ParamValidationError(report=report.generate_report())
    298         return self._serializer.serialize_to_request(parameters,
    299                                                      operation_model)

ParamValidationError: Parameter validation failed:
Invalid length for parameter AppSpecification.ContainerArguments, value: 0, valid range: 1-inf

[knakad]

Hi Chris!
Thanks for reaching out!

This is expected behavior. If you don't want any arguments passed in, you should either set it to "None" or avoid setting it at all.
By setting it to an empty string, you're hitting our service-lvl validations, which require an existing array to be of length greater or equal to 0.

Let me know if there's anything else I can clarify =)