Question

I’ve set up my app.yaml and data_uploader files as suggested in this document. My CSV file has some null values (the spreadsheet that I exported had some empty cells).

When I run the script, I get this error in the log file:
[ERROR ] Error in WorkerThread-0: Value should not be empty; received [].

My guess is that it is because some values are empty in the csv file, How can I make sure that the empty values are either imported as ” into the datastore, or not imported at all (the model properties are all optional).

Thanks, David.

Answer 1

You probably should customize your bulkloader.yaml giving the right directive in the property map section.

Check if the import_transform element on your model kind property that gives problem is set, and try to use the none_if_empty directive .

- property: fooproperty
  external_name: fooproperty
  import_transform: transform.none_if_empty(foopropertytype)

This is what none_if_empty does:

def none_if_empty(fn):
  """A wrapper for a value to return None if it's empty. Useful on import.

  Can be used in config files (e.g. "transform.none_if_empty(int)" or
  as a decorator.

  Args:
    fn: Single argument transform function.

  Returns:
    Wrapped function.
  """

  def wrapper(value):
    if value == '' or value is None:
      return None
    return fn(value)

  return wrapper

Afaik, bulkloader generates the bulkloader.yaml file inferring the proper configuration using the production datastore stats; just check if the assumptions made are correct.